JP2001228654A - Wet developer, transfer film for printing on curved face, and method of producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wet developer with which a liquid pressure transfer image can be printed on a transfer film for printing on a curved face by an on-demand printing method such as an electrophotographic method, and to provide a method of producing the wet developer, and to provide a transfer film which uses the wet developer and a method of producing the transfer film. SOLUTION: The copolymer resin covering toner particles consists of at least a first monomer unit which has electric insulating property and affinity with a dispersion medium and which is derived from 2-ethylhexylmethacrylate(EHMA), and a second monomer unit which has affinity with coloring agent particles and which is derived from 2-hydroxyethylmethacrylate(HEMA), with the copolymerization ratio of the first monomer unit to the second monomer unit (first monomer unit/second monomer unit) ranging from 90/10 to 70/30 by weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention mainly relates to the curved surface of various printing materials such as metal products, plastic molded products, ceramic molded products and the like. Which includes not only a non-planar portion such as a curved surface but also a flat portion).

More specifically, the present invention relates to a method for transferring an image (hydraulic transfer image) which can be transferred to the surface of a printing medium by using a liquid pressure such as a water pressure on a support film of a transfer film for curved surface printing. Developer for printing on a surface, a method for manufacturing the wet developer, a transfer film for curved printing on which a hydraulic transfer image is formed using the wet developer, and a method for manufacturing the transfer film for curved printing Things.

[0003]

2. Description of the Related Art Conventionally, a method of printing on various printing materials having a curved surface includes dry offset printing suitable for printing on a simple shape such as a conical shape and a box shape. Screen printing suitable for printing on unsuitable flat shapes, etc., printing requiring a thick ink layer, and further attaching a transfer paper consisting of a base material, wax layer, printing ink layer, and thermoplastic resin layer to the substrate Transfer printing to transfer the ink layer by heating from the base material side,
Then, the ink is transferred from the intaglio to the pad of silicon rubber and pressed against the substrate (a kind of offset printing). Can be mentioned.

Among such printing methods on a curved surface, a curling method (hydraulic pressure transfer, special curved surface printing) is one of the printing methods capable of painting (printing) on a printing medium having a particularly complicated shape. it can. According to printing on a curved surface by curl fitting, a transfer film formed by forming a transferable image on a support film made of a water-soluble or water-swellable film is placed on the water surface such that the transferable image is on the upper surface. Floating and printing the printed object from above,
The transfer image is transferred to the outer peripheral surface of the printing medium by bringing the transfer film into close contact with the surface of the printing medium by using water pressure (Japanese Patent Publication No. 52-41683, Japanese Patent Application Laid-Open No.
-33115).

[0005]

In preparing a transfer film for curved surface printing used for this curl fitting, a printing step of forming a transferable image on a support film has conventionally been performed by gravure printing. However, in order to form a transferable image for painting by gravure printing, it is necessary to prepare a printing plate, and for this,
There is a problem that it takes time and effort. Therefore, there is a problem that it is difficult to use a curved surface printed body in a short time and at low cost, such as when a prototype is created and evaluated at the development stage.

On the other hand, in the flow of small lots and many kinds in recent years, on-demand printing which can perform printing without using a printing plate has attracted attention. Various printed materials have been produced. The present inventors have already attempted to incorporate such an on-demand type printing method into the printing process of Carlfit, and as a result, transfer for curved surface printing capable of responding to recent demands of small lots and many kinds. It has become possible to produce films quickly and at low cost.

[0007] Among such on-demand systems, the electrophotographic system is a typical one. Due to its cost advantage over the conventional offset printing and gravure printing, mainly the small number of booklets, flyers, posters and the like are used. This electrophotographic method is beginning to be used for printing. Recently, a device capable of printing on a special material such as a film for flexible packaging has been proposed, and it is expected that the field of application thereof will be further expanded in the future.

In order to apply such an electrophotographic method to curl fitting, the present inventors have proposed incorporating the electrophotographic method into a printing process of a hydraulic transfer image of a transfer film for curved printing used for curl fitting. Have been considering.
However, usually, the toner used in the electrophotographic method has greatly different properties from the gravure ink used in the conventional curl fitting, and therefore, an attempt is made to print the transferable image of the transfer film for curved printing by the electrophotographic method. If so, various problems have arisen. One of the problems is that the transferable image of the transfer film for curved printing printed by the electrophotographic method in this way floats the transfer film for curved printing on a predetermined solvent, and then lowers the printing medium to the printing medium. Pattern (transferable image) when transferring to the surface of the printing medium with pressure
Is difficult to grow. Therefore, in such a transfer processing step, there is a problem that a crack may be generated in a picture (transferable image) during or after the transfer.

This problem is largely attributable to the solubility of the toner resin in the activator and the viscosity after dissolution. That is, in the transfer processing step in the usual curl fit, before floating the transfer film for curved printing on a predetermined solvent, the activator so that the transferable image swells with the swelling of the support film of the transfer film for curved printing. Is applied.
However, the chargeability and dispersion stability of the toner resin forming the transferable image greatly vary depending on the material.
For this reason, in order to print a liquid pressure transferable image by a method such as electrophotography on a support film of a transfer film for curved surface printing by using a method such as electrophotography, the toner particles only have excellent printability when printing by a method such as electrophotography. In addition, it is required to have a property of being able to swell sufficiently by a solvent that floats the transfer film for curved surface printing.

The present invention has been accomplished in view of the above problems, and a first object of the present invention is to provide an on-demand printing method utilizing an electrostatic action (for example, an electrophotographic method).
A wet developer capable of forming an image having excellent hydraulic transferability to the surface of a printing medium while having excellent printability when printing a hydraulic transferable image on a transfer film for curved surface printing, An object of the present invention is to provide a method for producing a developer.

A second object of the present invention is to provide an on-demand type printing method using the above-mentioned wet type developer,
An object of the present invention is to provide a transfer film for curved surface printing which is excellent in hydraulic transferability.

[0012]

According to the present invention, there is provided a wet developer for forming a liquid pressure transferable image, comprising toner particles obtained by coating colorant particles with a copolymer resin in an electrically insulating dispersion medium. A dispersed wet developer, wherein the copolymer resin comprises a first monomer unit having an affinity for an electrically insulating dispersion medium derived from 2-ethylhexyl methacrylate and colorant particles derived from 2-hydroxyethyl methacrylate. And a copolymerization ratio of the first monomer unit and the second monomer unit (first monomer unit / second monomer unit) in a weight ratio of 90/10 to 70/30. It is characterized by being.

The molecules of the copolymer resin used in the present invention include, as essential constituent units, 2-ethylhexyl methacrylate (EHMA) -derived first monomer unit having an affinity for an electrically insulating dispersion medium, and 2-hydroxyethyl. A second monomer unit having a colorant particle affinity derived from methacrylate (HEMA). The toner particles of the wet developer mainly include a core portion in which HEMA as the second monomer unit is adsorbed around the colorant particles and are insoluble in the electrically insulating dispersion medium. In the electrically insulating dispersion medium, the colorant particles in the nucleus portion are close to each other in the electric insulating dispersion medium because the outer peripheral portion is wrapped by the first monomer unit, EHMA, and is dissolved or swelled in the electrically insulating dispersion medium. Blocked, showing good dispersibility.

Further, by using EHMA as the first monomer unit of the copolymer resin, a printing method corresponding to on-demand, particularly a printing method including a step of developing an electrostatic latent image on a transfer film for curved surface printing can be used. When a transferable image is formed using the wet developer of the present invention, good printability in terms of image density and fixability by natural drying can be obtained.

Further, by using HEMA as the second monomer unit of the copolymer resin, when the transfer film for curved printing is floated on a liquid such as water, the transfer image can be sufficiently expanded and spread in accordance with the swelling of the support film. As a result, good hydraulic transfer suitability can be obtained.

The copolymer resin is preferably a 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymer resin.

The weight average molecular weight of the copolymer resin is 5
It is preferably from 000 to 150,000.

The weight ratio of the colorant particles to the copolymer resin (colorant particles / copolymer resin) is preferably 1/3 to 3/1.

In a preferred embodiment, the wet developer for forming a hydraulic transfer image contains at least a neutral or basic metal petronate as a charge control agent.
The toner particles are negatively charged.

The above-mentioned electrically insulating dispersion medium is preferably a branched aliphatic hydrocarbon.

In a preferred example of the wet developer, a yellow pigment, a cyan pigment, a magenta pigment or a black pigment is used as the colorant particles, and the first and second monomer units are used as the copolymer resin. A 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymer resin having a copolymerization ratio of 85/15 to 80/20 and a weight average molecular weight of 70,000 to 130,000 is used.

Next, a first method provided in the present invention for producing the above-mentioned wet developer includes a method in which a heated electrically insulating dispersion medium contains colorant particles, A first monomer unit having an affinity for an electrically insulating dispersion medium derived from -ethylhexyl methacrylate, and a second monomer unit having a colorant particle affinity derived from 2-hydroxyethyl methacrylate, wherein the first monomer Cooling while stirring a heated mixture in which a copolymer resin in which the copolymerization ratio of the unit and the second monomer unit (first monomer unit / second monomer unit) is 90/10 to 70/30 by weight is dissolved. Is performed to granulate the toner particles.

According to such a so-called cooling granulation method, the reproducibility of charging of toner particles is high, and a wet developer having the same polarity and a constant charge amount can be easily obtained under the same conditions. . Further, when the cooling granulation method is used, the content of the colorant particles in the toner particles can be extremely high.

During or after the cooling of the heated mixture, the granulation may be completed by adding an electrically insulating dispersion medium and continuing stirring.

It is preferable that the heated mixture is heated to 80 ° C. or higher.

The cooling rate of the heated mixture is 2 ° C./h to
It is preferably 20 ° C./h.

At any stage during or after the production of the wet developer, by adding at least neutral or basic metal petronate as a charge control agent to the wet developer or an intermediate product thereof, The toner particles can be negatively charged.

Next, a second method provided in the present invention for producing the above-mentioned wet developer includes a first monomer unit having an affinity for an electrically insulating dispersion medium derived from 2-ethylhexyl methacrylate, A second monomer unit having an affinity for colorant particles derived from 2-hydroxyethyl methacrylate, and a copolymerization ratio of the first monomer unit and the second monomer unit (first monomer unit / second monomer unit) ) Is 90/10 to 7 by weight
By heating a mixture containing at least a varnish containing a 0/30 copolymer resin and an electrically insulating dispersion medium under reduced pressure, the varnish solvent is removed from the mixture, and the mixture is depressurized and heated. Before, during or after any stage by adding the colorant particles into the mixture, the colorant particles are contained in the heated electrically insulating dispersion medium and the copolymer resin is dissolved A heated mixture is prepared, and the heated mixture is cooled with stirring to granulate toner particles.

In the present invention, the copolymer resin which coats the colorant particles has high tackiness in an isolated state and is difficult to handle, so that it is often prepared and stored in a varnish state. However, when the heated mixture with the varnish solvent remaining is cooled, the varnish solvent has high solubility in the resin, so that the resin hardly precipitates and the granulation becomes insufficient. In addition, since a polar solvent is often used as a varnish solvent, it is difficult to control the charge of the toner, in particular, to control the charge amount. Therefore, a mixture containing at least a varnish containing a copolymer resin and an electrically insulating dispersion medium is heated under reduced pressure to remove the varnish solvent from the mixture, and then cooled.

The granulation may be completed by adding an electrically insulating dispersion medium during or after cooling the heated mixture and continuing stirring.

It is preferable to remove the varnish solvent by heating the mixture containing at least the varnish and the electrically insulating dispersion medium to 80 ° C. or more while reducing the pressure to 300 to 30 mmHg.

The varnish solvent is removed by heating a mixture containing at least the varnish and the electrically insulating dispersion medium under reduced pressure to dissolve the copolymer resin in the electrically insulating dispersion medium. Prepare a heating solution, adding the colorant particles in the obtained heating solution, in the state of a pre-prepared heating mixture containing the colorant particles in a heated electrically insulating dispersion medium, preferable.

At any stage during or after the production of the wet developer, at least neutral or basic metal petronate is added as a charge control agent to the wet developer or an intermediate product thereof. The toner particles can be negatively charged.

Next, the transfer film for curved surface printing provided in the present invention is obtained by forming a hydraulic transfer image on one surface of a support film swelling in a predetermined solvent using the above-mentioned wet developer of the present invention. It is characterized by becoming.

The hydraulic transferable image formed by using the wet developer of the present invention can sufficiently expand and spread according to the swelling of the support film when the transfer film for curved printing is floated on a solvent. Curled-fit curved surface printing can be performed without generating cracks.

Next, the method provided in the present invention for producing the transfer film for curved printing described above is characterized by comprising at least the following steps (A), (B) and (C). . (A) a step of forming and carrying an electrostatic latent image on the surface of a dielectric, (B) a step of developing the electrostatic latent image using the above-described wet developer of the present invention, and (C) developing. Transferring the image to one surface of a support film swollen in a predetermined solvent to form a hydraulic transferable image.

Using the wet developing agent of the present invention, a printing method utilizing electrostatic action such as electrostatic transfer, electrostatic recording, electrostatic printing, etc., is used to transfer a liquid transfer property onto a support film of a transfer film for curved surface printing. An image can be formed. The wet developer of the present invention is applicable to an on-demand printing method such as an electrophotographic method among printing methods utilizing an electrostatic action, and is a transfer film for curved surface printing having a desired hydraulic transferable image. Can be formed quickly and easily without using a printing plate. Therefore, the productivity is high, and it is possible to quickly respond to requests such as trial production at the development stage, preparation of samples for presentation, and launch of products of various types and small quantities.

After transferring the image developed on the surface of the dielectric to the surface of the intermediate transfer member and temporarily supporting the image, the support film is further swollen from the surface of the intermediate transfer member into a predetermined solvent. A hydraulic transferable image may be formed by thermal transfer onto one surface.

A negatively charged electrostatic latent image is formed and carried on the surface of the dielectric, and the negatively charged wet developer is supplied to the surface carrying the electrostatic latent image to perform reversal development. Is also good.

As the dielectric, a photosensitive conductor which temporarily exhibits conductivity only in an exposed portion may be used, and the surface thereof may be exposed to form an image to form an electrostatic latent image.

[0041]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (1) Wet Developer and Method for Producing the Same The wet developer for forming a hydraulic transfer image provided in the present invention is a toner particle obtained by coating colorant particles with a copolymer resin. Is dispersed in an electrically insulating dispersion medium, wherein the copolymer resin has a first monomer unit having an affinity for an electrically insulating dispersion medium derived from 2-ethylhexyl methacrylate (EHMA), A second monomer unit having an affinity for colorant particles derived from hydroxyethyl methacrylate (HEMA), and a copolymerization ratio of the first monomer unit and the second monomer unit (first monomer unit / second monomer unit) Unit) is 9 by weight
It is in the range of 0/10 to 70/30. Hereinafter, the wet developer of the present invention will be described in detail.

(Colorant Particles) As the colorant particles used in the present invention, generally known organic pigments or inorganic pigments are used. Further, when the copolymer resin has a color, the copolymer resin itself can be used as the colorant particles. That is, in the present invention, the colorant particles may be independent components, or the copolymer resin may function as the colorant particles.

As the black colorant, for example, an inorganic colorant such as carbon black or triiron tetroxide, or an organic colorant such as cyanine black can be used.

As the yellow colorant, inorganic pigments such as graphite, cadmium yellow, yellow iron oxide, titanium yellow and ocher can be used. As a yellow colorant,
The following poorly soluble metal salts (azo lakes) can also be used.
That is, an acetoacetic acid arylide monoazo pigment,
Hansa Yellow G (CI No. pigment Yellow 1), Hansa Yellow 10G (CI No. pigment Yellow 3),
Hansa Yellow RN (CI No. pigment Yellow 6
5), Hansa Brilliant Yellow 5GX (CI No. p
igment Yellow 74), Hansa Brilliant Yellow 10
GX (CI No. pigment Yellow 98), Permanent Yellow FGL (CI No. pigment Yellow 97), Shimura Lake Fast Yellow 6G (CI No. pigment Ye)
llow 133), Lionol Yellow K-2R (CI No.
pigment Yellow 169); disazo yellow G (CI No. pigment
Yellow12), Disazo Yellow GR (CI No. pigmen)
t Yellow 13), Disazo Yellow 5G (CI No. pig
ment Yellow 14), Disazo Yellow 8G (CI No.p
igment Yellow 17), Disazo Yellow R (CI No.
pigment Yellow 55), permanent yellow HR (C.
I. No. pigment Yellow 83); Chromophthal Yellow 3G (CI No. pigment Yellow 9) which is a condensed azo pigment
3), Chromophthal Yellow 6G (CI No. pigment Y
ellow 94), Chromophthal Yellow GR (CI No. pi
gment Yellow 95); Hosta Palm Yellow H3G (CI No. pi), a benzimidazolone monoazo pigment
gment Yellow 154), Hosta Palm Yellow H4G (C.
I. No. pigment Yellow 151), Hosta Palm Yellow H2G (CI No. pigment Yellow 120), Hosta Palm Yellow H6G (CI No. pigment Yellow 175),
Hosta Palm Yellow HLR (CI No. pigment Yell
ow 156); Irgazine Yellow 3RLTN (CI No. pigment Yellow 11), which is an isoindolinone pigment.
0), Irgazin Yellow 2RLT, Irgazin Yellow 2GLT (CI No. pigment Yellow 109), Fastogen Super Yellow GROH (CI No. pigment)
Yellow 137), Fastogen Super Yellow GRO
(CI No. pigment Yellow 110) and Sandrin Yellow 6GL (CI No. pigment Yellow 173) can be used.

The following are examples of other yellow colorants. That is, flavantron (CI No. pigment Yellow 2
4), anthramirimidine (CI No. pigment Yellow)
108), phthaloylamide type anthraquinone (CI No.
pigment Yellow 123), Heliofast Yellow E3
R (CI No. pigment Yellow 99): an azo-based nickel complex pigment (CI No. pigment Gr) which is a metal complex pigment
een 10), Nitroso-based nickel complex pigment (CI No. pi
gment Yellow 153), azomethine-based copper complex pigment (CI
No. pigment Yellow117); a quinophthalone pigment,
Phthalimide quinophthalone pigment (CI No. pigment Yel
low 138) can be used.

As the magenta-based coloring agent, inorganic pigments such as cadmium red, red bengal, silver vermilion, lead red and antimony vermilion can be used. The following azo lake pigments can also be used as the magenta colorant. That is, Brilliant Carmine 6B (CI No. pigment Red 57:
1), lake red (CI No. pigment Red 53: 1),
Permanent Red F5R (CI No. pigment Red 4
8), Risor Red (CI No. pigment Red 49),
Persian orange (CI No. pigment Orange 17),
Black orange (CI No. pigment Orange 18),
Helio Orange TD (CI No. pigment Orange 1
9), Pigment Scarlet (CI No. pigmentRed
60: 1), Brilliant Scarlet G (CI No. pigm
ent Red 64: 1), Helio Red RMT (CI No. pigm)
ent Red 51), Bordeaux 10B (CI No. pigment Red)
63), Helio Bordeaux BL (CI No. pigment Red 5
4) etc. can be used.

As the magenta colorant, the following insoluble azo pigments (monoazo, disazo and condensed azo) can be used. That is, para red (CI No. pigment) which is a monoazo or disazo pigment
Red 1), Lake Red 4R (CI No. pigment Red)
3), permanent orange (CI No. pigment Orang
e5), permanent red FR2 (CI No. pigment
Red 2), permanent red FRLL (CI No. pi
gment Red 9), permanent red FGR (CI No.
pigment Red 112), Brilliant Carmine BS (C.
I. No. pigmentRed 114), permanent carmine FB
(CI No. pigment Red 5), P.E. V. Carmin HR
(CI No. pigment Red 150), permanent carmine FBB (CI No. pigment Red 146), Nova Palm Red F3RK-F5RK (CI No. pigment Red 17)
0), Nova Palm Red HFG (CI No. pigment Ora
nge 38), Nova Palm Red HF4B (CI No. pigment)
Red 187), Nova Palm Orange HL. HL-70 (C.
I. No. pigment Orange 36), P.I. V. Carmin HF4
C (CI No. pigment Red 185), Hosta balm brown HFR (CI No. pigment Brown 25), Vulcan orange (CI No. pigment Orange 16), pyrazolone orange (CI No. pigment Orange 13), pyrazolone red (CI No. pigment Red 38); Chromophtal Orange 4R (CI No.
pigment Orange 31), Chromophtal Scarlet R
(CI No. pigment Red 166) and Chromophthal Red BR (CI No. pigment Red 144).

As the magenta colorant, the following condensed polycyclic pigments can also be used. That is, pyranthrone orange (CI No. pigm) which is an anthraquinone pigment
entOrange 40), ant anthrone orange (CIN)
o. pigment Orange 168), dianthraquinonyl red (CI No. pigment Red 177); a thioindigo pigment, thioindigo magenta (CI No. pigment Vi)
olet 38), thioindigo violet (CI No. pig)
ment Violet 36), Thioindigo Red (CI No. pig)
ment Red 88); perinone pigment, perinone orange (CI No. pigment Orange 43); perylene pigment, perylene red (CI No. pigment Red 19)
0), perylene vermillion (CI No. pigment Red 1
23), Perylene Maroon (CI No. pigment Red 17)
9), Perylene scarlet (CINo. Pigment Red 14
9), perylene red (CI No. pigment Red 178);
Quinacridone red (C.A.
I. No. pigment Violet 19), quinacridone magenta (CI No. pigment Red 122), quinacridone maroon (CI No. pigment Red 206), quinacridone scarlet (CI No. pigment Red 207); pyrocholine pigments; Pigments can be used.

Other magenta colorants include rhodamine 6G lake (CI N
o. Pigment Red 81) can be used. Dyeable lake pigments are those which react with a water-soluble dye and a precipitant to form a lake and fix it.

As the cyan colorant, inorganic pigments such as ultramarine blue, navy blue, cobalt blue and cerulean blue can be used. The following can also be used as the cyan colorant. That is, a phthalocyanine pigment,
First Gemble-BB (CI No. pigment Blue 1
5) Sumiton Cyanine Blue HB (CI No. pig
ment Blue 15), cyanine blue 5020 (CI No.
pigment Blue 15: 1), Monastral Blue FBR (C.
I. No. pigment Blue 15: 2), Palomar Blue B-48
10 (CI No. pigment Blue 15: 3), Monastral Blue FGX (CI No. pigment Blue 15: 4), Lionol Blue ES (CI No. pigment Blue 15: 6), Heliogen Blue L6700F (CI No. pigment) Blue
15: 6), Sumika Print Cyanine Blue GN-O
(CI No. pigment Blue 15), Heliogen Blue L
7560 (CI No. pigment Blue 16), Fast
Sky Blue A-612 (CI No. pigment Blue 1
7), cyanine green GB (CI No. pigment Gre
en 7), cyanine green S537-2Y (CINo. p
igment Green 36), Sumiton Fast Violet RL (CI No. pigment Violet 23);
1, PB-64); a basic dye lake pigment, such as methyl violet phosphorous molybdate (PV-3), can be used.

A colorant, which is a so-called processed pigment, in which a resin is coated on the particle surface of the colorant, may be used.

In the present invention, a pigment having an average particle size of 0.1 to 100 μm in the secondary aggregation state is usually used as the colorant particles. The pigment can be included in the toner particles in a P / V ratio (pigment weight / resin weight) of up to 3/1%, preferably up to 2/1. The wet developer of the present invention hardly causes problems such as macroscopic aggregation even when a large amount of toner particles are contained, so that the pigment content can be drastically increased.

(Copolymer Resin) Examples of the copolymer resin for coating the colorant particles include a first monomer unit having an affinity for an electrically insulating dispersion medium derived from 2-ethylhexyl methacrylate (EHMA) and 2-hydroxyethyl methacrylate. (HEMA) and at least a second monomer unit having an affinity for colorant particles derived from (HEMA), wherein the copolymerization ratio of the first monomer unit and the second monomer unit (first monomer unit / second monomer unit) is 90/10 by weight
Those which are not less than 70/30 are used.

One of the main features of the present invention is to coat colorant particles with such a copolymer.
By specifying the monomer unit and copolymerization ratio of the copolymer resin in this way, a hydraulic transfer image is formed by an on-demand type printing method (for example, electrophotography) using a wet developer for a transfer film for curved printing. Good printability when obtained, and also, when hydraulically transferring an image from a transfer film for curved printing onto the curved surface of a printing medium, good hydraulic transfer suitability, that is, good elongation of the image Good adhesion to the curved surface of the image can be obtained.

The copolymer resin used in the present invention has, as essential constituent units, 2-ethylhexyl methacrylate (EHMA) -derived first monomer unit having an affinity for an electrically insulating dispersion medium and 2-hydroxyethyl. A second monomer unit having a colorant particle affinity derived from methacrylate (HEMA). The copolymer resin covers the colorant particles by adsorbing to the surface of the colorant particles via the portion of the second monomer unit in the molecular structure, thereby forming toner particles. The obtained toner particles mainly consist of a core portion in which HEMA as the second monomer unit is adsorbed around the colorant particles and are insoluble in the electrically insulating dispersion medium, and the periphery of the core portion is mainly the above-mentioned. Since it is composed of the outer peripheral portion which is wrapped by the first monomer unit, EHMA, and which dissolves or swells in the electrically insulating dispersion medium, in the electrically insulating dispersion medium, the colorant particles in the core portion are prevented from approaching each other. Rare and show good dispersibility.

Here, the affinity of the first monomer unit for the electrically insulating dispersion medium and the affinity of the second monomer unit for the colorant particles are relative to each other between the first monomer unit and the second monomer unit. Relationship. The affinity of the first monomer unit for the electrically insulating dispersion medium and the affinity of the second monomer unit for the colorant particles can be represented by a difference in solubility parameter (SP value) between the two substances. The smaller the difference in SP value between the two substances, the higher the affinity between them, and the larger the difference in SP value, the lower the affinity between them. Specifically, in the relationship between the copolymer resin and the solvent, the smaller the difference in the SP value is, the larger the solubility of the copolymer resin in the solvent is. In the relationship between the copolymer resin and the colorant particles, the smaller the difference in the SP value is, the smaller the difference is. Adsorption of the copolymer resin to the colorant particles increases.

In the present invention, from the viewpoint of the dispersibility of the toner particles, the SP value (δd) of the electrically insulating dispersion medium,
S of the monomer (EHMA) that derives the first monomer unit
It is preferable that the P value (δm ¹ ) and the SP value (δm ² ) of the monomer (HEHA) for deriving the second monomer unit satisfy the following relationship.

[0058]

| Δm ¹ −δd | ≦ 1.5 | δm ² −δd | ≧ 1.5 | δm ¹ −δm ² | ≧ 1.0 In the present invention, the SP value of the resin is defined as a molecular attractive constant. Use the value determined by The solvent SP
The values are Hildebrand-Scatchard solution theory (JH
Hildebrand, RL Scott, `` The Solbility of Nonele
ctrolytes "3rd Ed., Reinhold Publishing cop., New
York (1949), G. Scatchard, Chem., Rev., 8, 321 (19
It is obtained by considering the attractive force between molecules based on 31)),

[0059]

SP value (δ) = (ΔE _V / ΔV ₁ ) ^1/2 [where, ΔE _V : evaporation energy, V ₁ : molecular volume, ΔE
_V / ΔV ₁ : cohesive energy]. In the present invention, KL Hoy, J. Paint Technol., 42, 76 (1
970) at 25 ° C. are used.

Further, by using EHMA as the first monomer unit of the copolymer resin, the present invention can be carried out on a transfer film for curved surface printing by a printing method corresponding to on-demand, particularly a printing method including a step of developing an electrostatic latent image. When a transferable image is formed using the wet developer of the present invention, good printability in terms of image density and fixability by natural drying can be obtained.

Further, by using HEMA as the second monomer unit of the copolymer resin, good negative chargeability can be obtained when forming toner particles, particularly when forming toner particles by a cooling granulation method described later. It can be obtained with good reproducibility. If a good negatively charged toner is obtained, a negatively charged electrostatic latent image can be formed on a dielectric to perform reverse transfer, so that so-called "fog" (a phenomenon in which non-printed portions are stained with toner) is reduced. High quality images can be obtained. Particularly, in the electrophotographic method described later, since an organic photoreceptor is usually used as a dielectric, a negatively charged electrostatic latent image is often formed, and reversal development is performed using a negatively charged toner from the viewpoint of printability. Is preferred.

Moreover, by using HEMA as the second monomer unit of the copolymer resin, when the transfer film for curved printing is floated on a liquid such as water, the transferable image is sufficiently expanded and spread in accordance with the swelling of the support film. As a result, good hydraulic transfer suitability can be obtained.

In the present invention, for coating the colorant particles, typically, 2-ethylhexyl methacrylate and 2
-Hydroxyethyl methacrylate copolymerization ratio (EHM
A / HEMA) is a 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymer resin having a weight ratio of 90/10 to 70/30 (EHMA · HEMA).
Copolymer resin) is used. However, in the molecular structure of the copolymer resin, as long as the object of the present invention is not adversely affected,
A structural unit other than the first monomer unit or the second monomer unit may be included.

Among these copolymer resins, it is preferable to use 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymer resin. When this copolymer resin is used, toner particles are easily granulated, and are likely to be negatively charged. This copolymer resin is sufficiently soluble in the activator.

In the copolymer resin, the weight ratio of the first monomer unit to the second monomer unit (first monomer unit / second monomer unit) is not less than 90/10 and not more than 70/30. The copolymerization ratio (first monomer unit / second monomer unit) is particularly preferably in the range of 85/15 or more and 80/20 or less. Use of a copolymer resin having a copolymerization ratio within this range is suitable for a cooling granulation process described later. When the copolymerization ratio of the copolymer resin covering the surface of the toner particles is within this range, the image developed on the dielectric is transferred to the intermediate transfer member, and then thermally transferred to the support of the transfer film for curved printing. In a printing system, the toner particles exhibit good thermal transfer characteristics.

The weight average molecular weight of the copolymer resin is 5
It is preferably in the range of from 000 to 150,000, particularly preferably in the range of from 70,000 to 130,000. When the molecular weight of the copolymer resin is in this range, it is suitable for the cooling granulation process described below.

However, the copolymerization ratio, molecular weight, and other physical properties of the copolymer resin that give the best results also vary depending on the colorant particles, the electrically insulating dispersion medium, the method for producing the wet developer, and other conditions. Come. yellow,
When it is desired to produce each of cyan, magenta or black wet developer, usually a yellow pigment as a colorant particle,
A cyan pigment, a magenta pigment or a black pigment is used, and a copolymerization ratio (EHMA / HEMA) is 85 as a copolymer resin.
/ 15-80 / 20 and a weight average molecular weight of 70,00
By using 0-130,000 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymer resin to form toner particles by a cooling granulation method described below, the dispersibility of the toner particles can be improved, and the on-demand type printing method can be used. The toner particles are excellent in both printability and hydraulic transfer suitability.

The P / V ratio between the colorant particles and the copolymer resin is usually adjusted in the range of 1/3 to 3/1, preferably 1/2.
Adjust to the range of ２2/1. If the P / V ratio is less than 1/3, it becomes difficult to obtain a sufficient image density. On the other hand, when the P / V ratio exceeds 3/1, in a printing system in which an image developed on a dielectric is transferred to an intermediate transfer member and then thermally transferred to a support of a transfer film for curved surface printing,
Thermal transfer failure is likely to occur.

(Electrically Insulating Dispersion Medium) As the electrically insulating dispersion medium, a solvent having an electric resistance of 10 ¹⁰ Ω · cm or more is usually used, and a liquid aliphatic hydrocarbon having such an electric resistance is used. It is preferred to use. Examples of the liquid aliphatic hydrocarbon include n-paraffinic hydrocarbons, branched-chain aliphatic hydrocarbons (isoparaffinic hydrocarbons), a mixture of these paraffinic hydrocarbons, and halogenated aliphatic hydrocarbons. . More specifically, n-hexane (7.3), n-heptane (7.5), n-octane (7.5), nonane (7.6), decane (7.
7), dodecane (7.9), cyclohexane (8.
2), perchlorethylene (9.3), trichloroethane (9.9) and the like. The numbers in parentheses of the above compounds indicate the SP value of each solvent.

Particularly preferred are branched chain aliphatic hydrocarbons. Branched-chain aliphatic hydrocarbons are supplied by Exxon under the trade name Isopar. Isopar has grades such as Isopar E, Isopar G, Isopar H, Isopar L, Isopar C, Isopar M, etc.
An appropriate resin is selected according to the type of the copolymer resin. The SP value of Isopar is from 7.0 to 7.3.

(Other Additives) If necessary, additives such as an electrification control agent, a dispersant, a fixing agent, and a swelling accelerator may be added to the wet developer of the present invention.

The electrification control agent is used to impart a desired charge polarity and / or charge amount to the toner particles. As the electrification controlling agent, for example, neutral or basic metal petronates, phospholipids, and metal salt compounds of organic acids can be used.

The neutral or basic metal petronate is
A neutral or basic mixture containing large amounts of metal sulfonates and mineral oil. Examples of the metal constituting the neutral or basic metal petronate include calcium, magnesium, barium, and sodium. As the neutral or basic metal petronate, for example, basic calcium petronate (BCP), basic magnesium petronate (BMP), basic barium petronate (BBP), basic sodium petronate, neutral (neutral) Examples thereof include calcium petronate (NCP). Petronates include petroleum-extracted and synthetic products, and either one may be used.

[0074] Examples of the phospholipid include lecithin and sekhalin. Lecithin can be represented by the following formula:

[0075]

Embedded image [In the above formula, R ¹ CO and R ² CO each represent a saturated or unsaturated acyl group, and the number of carbon atoms is not particularly limited. ]

Examples of the metal salt compound of an organic acid include, for example,
Dialkyl sulfosuccinate metal salts such as cobalt dialkyl sulfosuccinate, manganese dialkyl sulfosuccinate, zirconium dialkyl sulfosuccinate, yttrium dialkyl sulfosuccinate, nickel dialkyl sulfosuccinate; manganese naphthenate, calcium naphthenate, zirconium naphthenate, cobalt naphthenate, naphthenate Iron, lead naphthenate, nickel naphthenate, chromium naphthenate, zinc naphthenate, magnesium naphthenate, manganese octylate, calcium octylate, zirconium octylate, iron octylate, lead octylate, cobalt octylate, chromium octylate, Zinc octylate, magnesium octylate, manganese dodecylate, calcium dodecylate, zirconium dodecylate, iron dodecylate, dodecylate , Cobalt dodecyl acid, chromic dodecyl acid, zinc dodecyl acid, metal soaps such as magnesium dodecyl acid; calcium dodecylbenzenesulfonate,
Alkyl benzene sulfonic acid metal salts such as sodium dodecyl benzene sulfonate and barium dodecyl benzene sulfonate can be used.

The charge control agent may be added in the minimum amount that exhibits the charge control effect. Usually, the charge control agent is added to the wet developer at a ratio of 0.01 to 50% by weight. The charge control agent exhibits a charge control effect when added at any stage after the production process of the wet developer or after the production process.

In particular, when the wet developer of the present invention is produced by the cooling granulation method described below, neutral or basic metal petronates may be used alone or in combination of two or more, or may be charged other than metal petronates. By combining with a control agent, negatively charged toner particles can be obtained with good reproducibility, and can be suitably used for forming a hydraulic transfer image for electrophotography. In particular, when basic barium petronate (BBP) is used, the total solid content of the colorant particles and the copolymer resin is 2%.
BBP is usually 1 to 2000g
By adding 10 g, preferably 2 to 5 g, good negative chargeability is easily obtained.

The dispersant is used to reduce the particle size of the toner particles to submicron units and / or narrow the particle size distribution.

As such a dispersant, for example, a polymer dispersant such as a polyhydroxycarboxylic acid ester can be used. The polyhydroxycarboxylic acid ester is a polymer of an ester derivative of hydroxycarboxylic acid represented by the following formula.

[0081]

HO-X-COOH wherein, in the above formula, X is a divalent saturated or unsaturated aliphatic hydrocarbon having 12 or more carbon atoms, and at least 4 There are carbon atoms. ]

Preferred ester derivatives of hydroxycarboxylic acid include, for example, hydroxycarboxylic acid alkyl esters such as methyl 12-hydroxystearate and ethyl 12-hydroxystearate; lithium 12-hydroxycarboxylate, 12-hydroxycarboxylic acid Examples thereof include metal salts of hydroxycarboxylic acids such as aluminum; amides of hydroxycarboxylic acids; and hardened castor oil.

The polyhydroxycarboxylic acid ester is a light gray brown wax-like substance obtained by polymerizing a hydroxycarboxylic acid ester by partially saponifying it in the presence of a small amount of amines or a catalyst. It contains various forms such as those esterified between molecules and those esterified in the molecule.

The polyhydroxycarboxylic acid ester is preferably a 3- to 10-mer hydroxycarboxylic acid ester. If the degree of polymerization of the polyhydroxycarboxylic acid ester is smaller than 3 or larger than 10, there is no compatibility with the dispersion medium, and the effect as a dispersant cannot be obtained. The amount of the polyhydroxycarboxylic acid ester to be added is not particularly limited, but is usually 0.01 to 200% by weight per resin weight. The polyhydroxycarboxylic acid ester may be added at any point during the production process before the granulation process.

As the fixing agent, various resins soluble in the dispersion medium can be used. More specifically, modified or unmodified alkyd resins, ordinary alkyl resins, synthetic rubbers,
Examples thereof include polyalkylene oxide, polyvinyl acetal (for example, polyvinyl butyral), and vinyl acetate resin.

[0086] The swelling accelerator is used for wet development in order to prevent the liquid pressure transferable image from expanding and spreading sufficiently in accordance with the swelling of the supporting film when the transfer film for curved surface printing is floated on the water surface, and to prevent the occurrence of cracks. It is added into the agent. The swelling accelerator penetrates between the toner particles forming the hydraulic transfer image and promotes the spread of the hydraulic transfer image by improving the fluidity between the toner particles when the support film swells. I do. As the swelling accelerator, a substance which is solid before use of the transfer film for curved surface printing and does not cause disturbance of an image, and becomes liquid during liquid pressure transfer and exhibits fluidity is preferably used. For example, substances which are very soluble in certain solvents can be added as swelling accelerators in wet developers. In this case, the image can be stretched and spread by applying the solvent dissolving the swelling agent to the image as an activator before floating the transfer film for curved surface printing on a predetermined solvent. Further, a substance which becomes liquefied when a certain kind of energy ray is added may be used as a swelling accelerator.

A substance which is liquefied by heating may be used as a swelling accelerator. In this case, the image of the transfer film for curved surface printing is irradiated with infrared rays, or the transfer film for curved surface printing is floated on a predetermined solvent, and the heated printing medium is lowered from above, or The image can be stretched and spread by floating the transfer film on a solvent heated to a predetermined temperature. Examples of the swelling accelerator which is liquefied by heating include, for example, animal waxes such as beeswax and whale wax, carnauba wax, candelilla wax, plant wax such as wood wax, paraffin wax, petroleum wax such as microcrystalline wax, Fischer-Tropsch wax, synthetic hydrocarbons such as low molecular weight polyethylene, wax compounds such as n-paraffin having 21 or more carbon atoms, fatty acids such as stearic acid, myristic acid, palmitic acid, and higher grades such as stearyl alcohol and polyvinyl ether. Examples thereof include alcohols, fatty acid esters of polyhydric alcohols such as sorbitan monostearate, polyolefin resins, epoxy resins, polyamide resins, polyester resins, and urethane resins.

The swelling accelerator is preferably added to the wet developer in an amount of 5 to 100 parts by weight, preferably 20 to 70 parts by weight, based on 100 parts by weight of the copolymer resin of the toner particles. When the amount is less than 5 parts by weight, the effect of promoting swelling is hardly obtained, and when the amount is more than 100 parts by weight, there is a possibility that a problem may occur in adhesion to a printing medium. The swelling accelerator may be added at any stage after the production process of the wet developer or after the production process.

(Production Method of Wet Developer) The wet developer of the present invention can be produced by, for example, a solvent replacement method or a cooling granulation method, or may be produced by other known methods. To produce the wet developer of the present invention by a solvent replacement method,
(1) The copolymer resin is dissolved in a solvent, (2) The solution in which the copolymer resin is dissolved is mixed with an electrically insulating dispersion medium in the presence of colorant particles, and then (3) the solvent may be removed. . Mixing the electrically insulating dispersion medium of (2) with the toner particles,
Alternatively, precipitation (granulation) is performed in at least one of the steps (3) of removing the solvent.

In order to produce the wet developer of the present invention by the cooling granulation method, (1) the electrically insulating dispersion medium is heated to dissolve the copolymer resin, and the electrically insulating dispersion medium is dissolved in the electrically insulating dispersion medium. The heating mixture may be prepared by dispersing the colorant particles simultaneously or separately with the copolymer resin, and (2) cooling the heating mixture. The toner particles are precipitated (granulated) in the cooling step (2) and the dilution / dispersion step performed as necessary thereafter.

In both the solvent replacement method and the cooling granulation method, additives such as a charge control agent are added at appropriate times according to each additive.

The cooling granulation method is particularly suitable for producing the wet developer of the present invention. According to the cooling granulation method, the reproducibility of charging of the toner particles is high, and a wet developer having the same polarity and a constant charge amount can be easily obtained under the same conditions. In the case of the cooling granulation method, the content of the colorant particles in the toner particles can be extremely high.For example, while retaining the polarity and charge amount suitable for practical use, The P / V ratio (colorant particle weight / copolymer resin weight) was calculated as 2/1 to 3/1, based on the content of the colorant particles.
It can be.

Therefore, the cooling granulation method will be described below in detail. In the cooling granulation method, first, an electrically insulating dispersion medium is heated to dissolve a copolymer resin, and a colorant particle is added to the electrically insulating dispersion medium to prepare a heated mixture. In the mixture in a high temperature state, the copolymer resin is preferably completely dissolved, but may be in a swollen state. Further, even if it is in an insoluble state, it is sufficient that partial homopolymer chains present in the copolymer resin are well dispersed. In order to sufficiently dissolve the copolymer resin, the heated mixture is preferably heated to 80 ° C. or higher.

The colorant particles may be added to the electrically insulating dispersion medium simultaneously with the copolymer resin, or may be added separately. When the colorant particles are added to the electric insulating dispersion medium separately from the copolymer resin, a heating solution of the electric insulating dispersion medium in which the copolymer resin is dissolved and an electric insulating medium containing the colorant particles are used. Heated mixture of dispersion medium (Preliminarily prepared heated mixture)
May be separately prepared, and the heated solution and the pre-prepared heated mixture may be mixed. In order to avoid a sudden drop in the liquid temperature when the pre-prepared heating mixture is mixed with the heating solution, the pre-prepared heating mixture is also preferably heated to 80 ° C. or higher.

The dispersant is added to the heated mixture in an amount of 0.1 to 1%.
When the content is about 10% by weight, the dispersion state of the toner particles can be improved.

In the present invention, the copolymer resin that coats the colorant particles has a glass transition temperature of room temperature or lower, and when isolated, has high tackiness and is difficult to handle. For this reason, the copolymer resin is often prepared and stored in a varnish state. In the varnish, the copolymer resin is dissolved or dispersed in a solvent obtained by polymerizing the copolymer resin (polymerization solvent) or a solvent added after the polymerization. In the varnish, for example, a toluene / isopropanol mixed solution used as a polymerization solvent remains as a varnish solvent as it is.

When toner particles are formed by a cooling granulation method using such a varnish, if the heated mixture in which the varnish solvent remains is cooled, the solubility of the varnish solvent in the resin is high. Are difficult to precipitate and granulation becomes insufficient. In addition, since a polar solvent is often used as a varnish solvent, it is difficult to control the charge of the toner, in particular, to control the charge amount. Therefore, a mixture containing at least a varnish containing a copolymer resin and an electrically insulating dispersion medium is heated under reduced pressure to remove the varnish solvent from the mixture, and then cooled. In addition, before the mixture containing the varnish and the electrically insulating dispersion medium is decompressed and heated, by adding the colorant particles to the mixture at any stage during or after, the varnish solvent is substantially contained. It is preferable to obtain a heated mixture which is not contained, that is, a mixed solution in which the heated electrically insulating dispersion medium contains the colorant particles and the copolymer resin is dissolved.

Before the start of the decompression / heating step, the colorant particles
It may be added to the mixture at any stage during or after completion. For example, a varnish containing a copolymer resin and an electric insulating dispersion medium are mixed, and the varnish solvent is removed by heating under reduced pressure, and the copolymer resin is dissolved in the electric insulating dispersion medium. A heating solution substantially free of a varnish solvent is prepared by adding a colorant particle as it is or in a pre-prepared heating mixture to the obtained heating solution. A mixture can be prepared. In addition, the varnish containing a copolymer resin, the electrically insulating dispersion medium, and the colorant particles are all mixed, and then the varnish solvent is removed by heating under reduced pressure to prepare the heated mixture. .

The mixture containing the varnish, the electrically insulating dispersion medium and, if necessary, the colorant particles is heated to 80 ° C. or more under a reduced pressure of 300 to 30 mmHg to remove the varnish solvent. Removal is preferred. When the degree of pressure reduction is less than 300 mmHg or when the heating temperature is less than 80 ° C., it is difficult to sufficiently remove the varnish solvent. On the other hand, if the degree of pressure reduction is lower than 30 mmHg, the electrically insulating dispersion medium is also gradually removed together. Further, it is preferable to gradually increase the degree of reduced pressure, because the copolymer resin can be rapidly precipitated. As a preferable pressure reduction pattern, for example,-
100mmHg / 0.5hour at normal pressure to 100
mmHg, then -20mmHg / 0.5h
The pressure is reduced from 100 mmHg to 30 mmHg at the speed of our.

Next, in the step of cooling the heated mixture, the prepared heated mixture is cooled with stirring to precipitate (granulate) the toner particles. It is preferable to cool the heated mixture gradually rather than rapidly. The cooling rate affects the particle size of the toner particles and aggregation between the toner particles. The cooling rate tends to be large when the cooling rate is increased, and tends to be small when the cooling rate is reduced. The cooling performed gradually may be performed at least between the temperature at which the copolymer resin in the heated mixture starts to precipitate and the temperature at which the precipitation of the copolymer resin stops, and the temperature is equal to or higher than the temperature at which the copolymer resin starts to precipitate or the precipitation stops. When the temperature is lower than the required temperature, the cooling is not necessarily required. The rate of cooling varies depending on the electric insulating dispersion medium used, the copolymerization ratio of the copolymer resin, and the like, but in many cases, it is preferably in the range of -20 ° C / hour to -2 ° C / hour. If the cooling rate is less than -2 ° C / hour, the work efficiency is deteriorated, which is not practical. On the other hand, -20 ° C / h
If the cooling rate exceeds our, rapid granulation occurs, so that the toner characteristics are likely to deteriorate.

In the heated mixture and the heated solution, at least one of the first monomer unit and the second monomer unit, which are the molecular chains of the copolymer resin, dissolves and swells in the heated electrically insulating dispersion medium. Or dispersed at the molecular level and dissolved as a resin. Then, by cooling the heated mixture, at least one of the molecular chains of the copolymer resin is dissolved, swells, or changes from a state dispersed at a molecular level to an insoluble state in the electrically insulating dispersion medium. Precipitation of the copolymer resin occurs. When the copolymer resin precipitates, the molecular chain of the copolymer resin is formed on the surface of the colorant particle via the second monomer unit having a higher affinity for the colorant particle than for the electrically insulating dispersion medium. And the toner particles are entangled in such a manner as to enclose the colorant particles, thereby forming toner particles.

The surface of the toner particles thus precipitated is rich in a portion of the first monomer unit having a high affinity for the electrically insulating dispersion medium, and is dissolved or swelled in the electrically insulating dispersion medium. Thus, even if a large amount of colorant particles are contained, contact between the colorant particles is avoided, and excellent dispersion stability is exhibited.

The amount of the copolymer resin dissolved in the electrically insulating dispersion medium is optional depending on the type of the dispersion medium and the heating temperature.
Therefore, when the toner particles precipitate (granulate) in the subsequent cooling step, a concentrated dispersion of the toner particles may be directly obtained. However, usually, the toner particles are in contact with each other and are in a dispersed state. An unsintered, clay-like mixture is obtained. When such a clay-like mixture is obtained, toner particles can be formed and granulation can be completed by adding an electrically insulating dispersion medium and continuing stirring during or after the cooling operation. . Then, the toner particles are adjusted to a desired concentration while maintaining the dispersion stability of the toner particles by further adding an electrically insulating dispersion medium to the concentrated dispersion of the toner particles obtained by the completion of the granulation. be able to.

Thus, the wet developer of the present invention is obtained. The core portion of the toner particles is mainly formed by the colorant particles and the portion of the second monomer unit adsorbed on the surface of the colorant particles, and is insoluble in the electrically insulating dispersion medium. An outer edge portion rich in the first monomer unit having a high affinity for the electrically insulating dispersion medium is formed. Accordingly, the toner particles are well dispersed in the wet developer, and even if the particle concentration is increased, gelation, macroscopic aggregation, precipitation, and the like do not occur, and the dispersion stability is excellent.
The content ratio of the toner particles in the wet developer is usually 0.01 to 80% by weight, preferably 0.1 to 50% by weight.
And

(2) Transfer Film for Curved Surface Printing and Method for Producing the Same A curved surface is formed by a printing method utilizing an electrostatic action such as electrostatic transfer, electrostatic recording, or electrostatic printing using the wet developer of the present invention. An image having hydraulic transferability can be formed on the support film of the transfer film for printing.

FIG. 1 is an example of a transfer film for curved surface printing obtained by an on-demand printing system utilizing electrostatic action using the wet developer of the present invention, and its cross section is schematically shown. Things. In FIG. 1, a transfer film for curved printing 1 is a liquid printed by an on-demand printing system using an intermediate layer 3 and an electrostatic action on one surface of a support film 2 swelling in a predetermined solvent. The layer of the pressure transferable image 4 and the adhesive layer 5 covering the hydraulic transferable image are laminated in this order. Hereinafter, such a transfer film for curved surface printing will be described in detail.

(Support Film) The support film of the transfer film for curved surface printing swells sufficiently on the solvent during the transfer on the solvent in the curl-fit printing step.
Further, it is preferable that the material has suitability for multicolor printing and further has a transfer property, that is, a property that sufficiently wraps around the surface of the curved surface print. In the present invention, “swells in a predetermined solvent” means that it has either property of dissolving or swelling in a predetermined solvent.

Specific examples of such a support film include, for example, dextrin, gelatin, glue, casein, shellac, gum arabic, starch, protein, polyvinyl alcohol, polyacrylamide, sodium polyacrylate, polyvinyl methyl ether, Methyl vinyl ether and maleic anhydride copolymer, vinyl acetate and itaconic acid copolymer, polyvinylpyrrolidone, or cellulose, acetylcellulose, acetylbutylcellulose, carboxymethylcellulose, methylcellulose,
Cellulose derivatives such as hydroxyethyl cellulose,
Sodium alginate and the like can be mentioned, and these can be used alone or as a mixture.

In the present invention, the predetermined solvent, that is, the solvent that causes the transfer film to float and swell in the curl fit is not particularly limited, but is preferably water from the viewpoint of cost and safety.

As described above, when the predetermined solvent is water,
The support film is preferably a film that swells in water.Specifically, among the above-mentioned films, a starch-based film, a polyvinyl alcohol-based film, a film composed of a mixed system of polyvinyl alcohol and starch, or a paper made of the above-described material is used. , A nonwoven fabric, a film coated on a liquid-permeable base such as various porous films, or a laminated film.

In the present invention, a film containing a polyvinyl alcohol resin as a main component is most preferable. The film mainly composed of the polyvinyl alcohol resin has a degree of polymerization, a degree of saponification, and the addition of additives such as starch.
By changing various conditions, the mechanical strength required for on-demand type printing such as electrophotography, the hygroscopicity during handling, the speed of softening by absorbing water after floating on water, The time required for diffusion, the ease of deformation during transfer, and the like can be controlled. An example of a preferred film mainly composed of polyvinyl alcohol (PVA) resin is composed of 80% by weight of PVA, 15% by weight of a high molecular weight water-soluble resin, and 5% by weight of starch, and has an equilibrium water content of about 3%.

The thickness of such a support film is 10 to
It is preferably within a range of 100 μm, more preferably 20 to
It is within the range of 60 μm.

(Intermediate Layer) In the transfer film for curved printing according to the present invention, a hydraulic transfer image may be directly printed on the surface of the support film, but if necessary, the support film and the hydraulic transfer image may be printed. An intermediate layer may be provided between the first and second layers. This intermediate layer is used to fix a pattern (hydraulic transfer image) on the support film when it is difficult to fix and fix the pattern when the hydraulic transfer image is printed directly on the support film.
It is provided for fixing, and another purpose is that when the film after printing is floated on a predetermined solvent, the image is disturbed due to uneven swelling of the hydraulic transferable image. This is provided in order to prevent

From the above-mentioned point, this intermediate layer needs to have a property capable of fixing the toner used for image recording to the surface or inside thereof. Further, the intermediate layer is insoluble in a predetermined solvent for swelling and dissolving the support film, and has a swelling property with respect to an activator applied on a hydraulic transfer image at the time of curved printing, an adhesive property with respect to a surface of a printing medium, and the like. It is preferred to have.

The intermediate layer provided in the present invention has a resin as a main component and is mixed with various additives as necessary. As the resin used for the intermediate layer, a resin having a low Tg is preferable similarly to the resin used for the toner vehicle, since it has appropriate adhesiveness.

Examples of such a resin include a pure frame or a modified alkyd resin such as a fatty acid-modified phthalic alkyd and a maleic alkyd; (meth) acrylic resins such as polyethyl acrylate and methacrylic acid / lauryl methacrylate copolymer; Metal salts thereof; acrylamide / acryl copolymer resins such as acrylamide / 2-ethylhexyl methacrylate copolymer; styrene resins such as styrene / butadiene copolymer and styrene / isoprene copolymer; styrene / n-butyl methacrylate copolymer Styrene acrylic resins such as styrene resins; various saturated and unsaturated polyester resins; polyolefin resins such as polyisobutylene; polyacetal resins such as polyvinyl formal, polyvinyl butyral, and polyvinyl acetal; Polyethylene resins such as ethylene / vinyl acetate copolymers and ethylene / ethyl acrylate copolymer resins; polyvinylpyrrolidone and its copolymers; alkylene oxide resins such as polyethylene oxide and carboxylated polyethylene oxide; polyether polyols; Sodium alginate; natural or semi-synthetic resin such as gelatin and its derivatives, casein, trolloay, tragacanth gum, pullulan, vectin, carrageenan, glue, albumin, various starches, paste, soybean protein; terpene resin; ketone resin Rosin and rosin ester can be used. These resins may be used not only as a homopolymer but also as a blend within a compatible range.

Further, in order to improve the fixing property of the toner, an appropriate surface unevenness or void may be provided in the intermediate layer. For this purpose, a filler is mixed into the intermediate layer. Examples of the filler used include silica; alumina; kaolinite; natural or synthetic smectite clay minerals such as montmorillonite, organic montmorillonite, saponite, teniolite, hectorite and derivatives thereof; talc; calcium carbonate; magnesium carbonate; Barium sulfate; various zeolites; titanium oxide; cerium oxide; magnesium oxide; zirconium oxide; sodium silicate; calcium silicate; potassium silicate; magnesium silicate; aluminum silicate: diatomaceous earth; zinc sulfide; zinc hydroxide; zinc carbonate; Tin; magnesium sulfate;
Inorganic pigments such as aluminum hydroxide, hydrotalcite, lithobon, and carbon resin pigments; polystyrene resin; urea resin; benzoquinamine plastic pigment; melamine resin; silicone resin; polyurethane resin; polyester resin; Organic pigments such as polyacrylic resin; polyacrylamide resin; polypropylene; polyvinyl chloride; and polyvinylidene chloride. Which of the above-mentioned materials is selected and what kind of structure of the intermediate layer is selected is appropriately designed according to the image forming mode.

The means for forming such an intermediate layer on the support film is not particularly limited, but means such as gravure coat, offset gravure, roll coat, bar coat, spray coat, ultrasonic coat, etc. It is formed by, for example, dissolving the forming material such as the resin described above in an appropriate solvent. The thickness of such an intermediate layer varies greatly depending on the type of material used for the intermediate layer, but is preferably in the range of ^{2 to} 30 g / m ² .

(Hydraulic Transferable Image) On the support film provided with an intermediate layer as required, using the wet developer of the present invention, electrostatic transfer, electrostatic recording, electrostatic printing, etc. By performing printing utilizing various functions, a hydraulic transfer image can be formed. In the present invention, any printing method using an electrostatic action is applicable, but, for example, by developing an electrostatic latent image formed on the surface of a dielectric, Forming a visible image and transferring the formed visible image to a printing substrate to obtain a printed product, or electrostatic latent image directly on the surface of the printing substrate having a dielectric surface and developing it Electrostatic recording to obtain a printed product by forming a visible image, or carrying a charged toner on a gravure plate in the form of an image and applying a bias to the surface of the printing substrate, and applying a bias to the surface of the printing substrate from the gravure plate Electrostatic gravure printing or the like that obtains a printed product by transferring a toner to form a visible image can be performed.

When the wet developer of the present invention is used, an image having excellent swelling property at the time of curved surface printing can be obtained by an on-demand type printing system which does not require a printing plate such as electrostatic transfer or electrostatic recording. Can be formed.

The wet developer of the present invention develops an electrostatic latent image formed on a dielectric, forms a visible image, and transfers the formed visible image to a printing medium. When applied to a method of transferring to a surface (particularly, thermal transfer), it is very excellent in printability, so that it is possible to obtain a liquid pressure transferable image having excellent swellability at the time of curved surface printing and extremely excellent image quality. .

Here, the dielectric material forms an electrostatic latent image,
It refers to a support member having a dielectric surface that can be carried. Dielectrics are not limited to those that can always maintain dielectricity, such as those used in ion printers. For example, dielectrics are reversibly reversible, such as photosensitive conductors (photoconductors) in electrophotographic printers. Things that change,
It may have an invariable conductive part like an electrostatic printing plate of electrostatic lithographic printing. Therefore, the method of forming an electrostatic latent image on a dielectric may be determined according to the properties of the dielectric, and is not particularly limited. For example, in the case of an electrophotographic system, an electrostatic latent image can be formed by exposing an image or a negative pattern thereof on a photoreceptor, and in the case of an ion printer system, a surface of a dielectric material is formed by a needle electrode or the like. To form an electrostatic latent image, and in the case of electrostatic lithographic printing, by supplying ions to an electrostatic printing plate provided with conductive portions in the form of an image to be printed or its negative pattern, a static image is formed. An electrostatic latent image can be formed.

Further, the visible image obtained by developing the electrostatic latent image thus formed is not limited to one having a design property, and may be various patterns or solid coating.

FIG. 2 shows an example of a printing system suitable for forming a hydraulic transferable image on a curved printing film using the wet developer of the present invention. The electrophotographic system is applied to the illustrated printing system 6.

In FIG. 2, the latent image holding means 7 has a cylindrical photosensitive drum 12 as a dielectric.
The photosensitive drum is formed of a photosensitive member and usually has a dielectric property. However, only a portion irradiated with light such as a laser beam temporarily exhibits conductivity. The photosensitive drum can form and carry an electrostatic latent image on its side surface portion 12a, and rotates around its own central axis 12b in the direction of arrow d.

The side surface portion 12a of the photosensitive drum, that is, the surface on which the electrostatic latent image is held, is first cleaned by the charge removing / cleaning means 8 to make it electrically neutral. The charge removing / cleaning means 8 includes at least a cleaning mechanism and a charge removing mechanism. As the cleaning mechanism, for example, a blade 13 as illustrated is used. When applying the electrophotographic method, that is, when using a photoconductor,
Normally, a large amount of the exposure device 14 is used as a charge removing mechanism, and the entire surface 12a of the electrostatic latent image is exposed to a large amount of light to make it electrically neutral.

After the electrostatic latent image carrying surface 12a has passed through the discharging / cleaning means 8, it reaches the latent image forming means 9, and
There, an electrostatic latent image is formed. When the electrophotographic method is applied, the latent image forming unit has at least a charging mechanism and an exposure mechanism. The charging mechanism is a mechanism for uniformly charging the entire surface 12a of the electrostatic latent image, and uses, for example, a corona discharge device 15 such as a scorotron as the charging mechanism.
The exposure mechanism is a mechanism that can selectively irradiate a light beam having an appropriate wavelength and energy on the holding surface 12a of the electrostatic latent image in accordance with an image to be reproduced. In addition, a laser beam irradiation device 16 capable of changing energy is used as an exposure device.

When the surface of a photoreceptor, which is a dielectric material in electrophotography, is uniformly charged and then exposed, only a portion irradiated with light temporarily develops conductivity and becomes electrically neutral. , An electrostatic latent image is formed. In electrophotography using an organic photoreceptor, a negatively charged electrostatic latent image is usually formed. When a positive image is to be developed after the exposure, an electrostatic latent image of a positive pattern is formed by the exposure mechanism, and when reversal development is to be performed after the exposure, a negative electrostatic image of the negative pattern is formed by the exposure mechanism. Generally, reversal development is more "fogging" than normal image development
(Phenomenon in which non-printed portions are stained by toner) is small.
In this respect, there is an advantage of performing reversal development.

After forming and carrying the electrostatic latent image on the electrostatic latent image holding surface 12a, the latent image forming section moves in accordance with the rotation of the photosensitive drum 12 and reaches the developing means 10, where the wet developer is supplied. Then, the electrostatic latent image is developed. Developing means 1
The reference numeral 0 generally includes, together with the developer supply section, a measuring mechanism for removing excess developer adhering to the development surface and keeping the amount of adhesion constant.

Normally, while the non-contact positional relationship between the developer supply unit and the surface for carrying the electrostatic latent image is maintained, the electrostatic latent image is carried from the developer supply unit by the electrostatic action. A wet developer is supplied to the surface. In FIG. 2, a cylindrical developing roller 17 is used as a developer supply unit. The developing roller 17 has a storage tank 19 at the lower portion of the side portion 17a.
And a very narrow (usually about 100 μm) gap is formed at the closest portion between the side surface portion 17a and the electrostatic latent image carrying surface 12a.
2 and rotate around its own central axis 17b. Since the wet type developer is scraped up by the side portion 17a of the rotating developing roller, the thickness of the liquid film and the distance of the minute gap between the side portion 17a of the developing roller and the holding surface 12a of the electrostatic latent image are reduced. By adjusting, the minute interval is filled with the wet type developer.

Then, the toner selectively adheres to the charged portion or the non-charged portion of the electrostatic latent image, and the visible image is developed. When performing normal image development, using a wet developer charged to the opposite polarity to the electrostatic latent image, the toner in the developer is attracted to the charged portion of the electrostatic latent image by electrophoresis and adhered, Visualize the normal image of the latent image. On the other hand, when performing reversal development, a wet developer charged to the same polarity as the electrostatic latent image is used, and an appropriate bias voltage is applied between the developing roller and the photosensitive drum to make the toner in the developer static. The latent image is attached to the uncharged portion of the latent image to visualize the inverted image of the latent image.

As a measuring mechanism for keeping the amount of the developer adhered after the development, for example, a reversing roller 18 can be used.

Instead of providing the developer storage tank 19, as shown in FIG. 3, on the side surface 17a of the developing roller, or on the side surface 17a of the developing roller and the side surface 1 of the photosensitive drum.
The wet developer 20 may be forcibly supplied to the minute gap between 2a by injection, dropping, spraying, or the like.

The developing roller 1 is used as a developer supply section.
Instead of providing 7, another developing device may be used, and the developing device is not particularly limited as long as it is a developing device for a wet developer. For example, FIG.
As shown in (1), a developing electrode 23 which maintains a non-contact positional relationship along the side surface 12a of the photosensitive drum may be provided.
The developing electrode 23 is disposed so as to form a very narrow (usually about 100 μm) gap 24 between the developing electrode 23 and the side surface 12 a of the photosensitive drum. By supplying and circulating the developer from the supply path 23a into the minute gap 24, the electrostatic latent image carried on the side surface 12a of the photosensitive drum can be developed. When performing development, particularly when performing reversal development, an appropriate bias voltage is applied between the development electrode 23 and the side surface portion 12a of the photosensitive drum.

The image developed on the side surface of the photosensitive drum 12 moves in accordance with the rotation of the photosensitive drum and reaches the output unit 11, where it is transferred to the intermediate transfer body 21 and temporarily carried thereon. Is thermally transferred to the support film 2 of the transfer film for use. An image developed on a dielectric material such as a photosensitive drum is supported on a transfer film 2 for a curved surface printing transfer film.
May be directly pressure-transferred or heat-transferred, but if an appropriate intermediate transfer member is interposed between the dielectric and the printing medium, the image can be formed even if the contact pressure between the dielectric and the intermediate transfer member is relatively weak. Can be transferred, so that mechanical damage to the dielectric can be reduced. Further, by interposing the intermediate transfer member, the image can be thermally transferred (re-transferred) to the support film without directly heating the dielectric, so that thermal damage to the dielectric can be reduced. Therefore, the dielectric is hardly deteriorated. Since an organic photoreceptor usually used in electrophotography is easily damaged by heat, an intermediate transfer member is extremely effective.

The output means 11 is provided with at least a heating mechanism for heating the intermediate transfer member 21 and the image bearing surface of the intermediate transfer member to a temperature at which heat transfer can be performed. A pressing member such as an impression cylinder 22 is provided to obtain a contact pressure.

In FIG. 2, the intermediate transfer member 21 has a cylindrical shape, and the side surface portion 21a functions as a temporary image bearing surface. The intermediate transfer member 21 is arranged in parallel with the photosensitive drum so that the side surface portion 21a thereof contacts the side surface portion 12a of the photosensitive drum, and rotates around its own central axis 21b in synchronization with the rotation of the photosensitive drum. The impression cylinder 22 cooperates with the intermediate transfer body 21 at the position where the thermal transfer is performed, and
Are arranged in close proximity to or in contact with the intermediate transfer member 21 and in parallel with the intermediate transfer member. In the printing system 6, a heater is provided inside the intermediate transfer member as a heating mechanism, but is not shown.

The image-holding surface 21a has an appropriate wettability with respect to toner particles for receiving an image from a dielectric material such as a photosensitive drum, and a molten toner for re-transferring the image to a supporting film. The particles are required to have an appropriate release property and heat resistance to withstand the thermal transfer process. Further, in order to improve transferability from the dielectric to the intermediate transfer member and transferability from the intermediate transfer member to the support film, the intermediate transfer member is preferably made of a material having a soft rubber-like elasticity. For this reason, silicone oil and fluorine-based surfactants are contained in rubber-based materials with low surface energy such as silicone rubber and fluorine rubber, or flexible resins such as acrylic rubber, styrene butadiene rubber, acrylonitrile butadiene rubber, and chloroprene rubber. It is preferable to form the whole or surface of the intermediate transfer member using a material having low surface energy and flexibility by adding an additive such as

In order to ensure flexibility with low surface energy, a low energy interface layer made of a material such as silicone is formed on the surface, and an adhesion improving layer made of a flexible material such as urethane rubber is formed on the base. An intermediate transfer member having a two-layer structure or an intermediate transfer member having a structure of three or more layers by adding other functional layers as necessary may be used.

The image developed on the side portion 12a of the photosensitive drum is rotated by the contact rotation between the photosensitive drum and the intermediate transfer member.
The image is transferred onto the side surface 21a of the intermediate transfer member. In order to cope with image disturbance at the time of transfer due to a potential difference between an image portion and a non-image portion on the side surface portion 12a of the photosensitive drum, the photosensitive drum may be exposed before transfer. Further, the side portion 1 of the photosensitive drum
When an appropriate bias voltage is applied between the second transfer member 2a and the side surface portion 21a of the intermediate transfer member, transfer is facilitated. Then, the image temporarily carried on the intermediate transfer body is retransferred onto the support film 2 of the transfer film for curved surface printing by thermal transfer. During thermal transfer, the image bearing surface of the intermediate transfer member is heated to a temperature equal to or higher than the melting point of the copolymer resin covering the toner particles, usually from about 60 ° C. to about 150 ° C.

In this way, a hydraulic transferable image is formed directly on the support film of the transfer film for curved printing or via the intermediate layer, and the transfer film for curved printing is obtained. However, an adhesive layer may be further provided on the hydraulic transfer image. On the other hand, the side surface portion 12a of the photosensitive drum returns to the position of the charge removing / cleaning means 8 after emitting the image, and shifts to the next printing cycle.

(Adhesive Layer) When an image is transferred from a transfer film for curved printing onto a printing medium by curl fitting, depending on the type of toner constituting the layer of the hydraulic transfer image,
Adhesion with a printing medium may be poor. In particular, when the amount of the swelling accelerator added is large, the adhesiveness to the printing medium may decrease. In such a case, by providing an adhesive layer on the layer of the hydraulic transferable image, it is possible to maintain good adhesiveness with the printing medium.

Such an adhesive layer is made of one or more resin materials which swell in a specific solvent and exhibit adhesiveness to a printing medium. As such a resin, for example,
Cellulose derivatives such as ethylcellulose, nitrocellulose and cellulose acetate; pure or modified alkyd resins such as fatty acid-modified phthalic acid alkyd and maleic acid alkyd; polymethacrylic acid, polymethyl methacrylate, 2-ethylhexyl methacrylate and methyl methacrylate Coalescence, lauryl methacrylate N, N-
(Meth) acrylic resin such as dimethylacrylamide copolymer; styrene-based resin such as styrene / n-butyl methacrylate copolymer, polyvinyl toluene, styrene / isoprene copolymer; polyester resin; epoxy-based resin; polyurethane-based resin; Resins; polyethylene-based resins such as ethylene-vinyl acetate copolymer and ethylene-ethyl acrylate copolymer resin; amide resins; polyvinyl alcohol resins; gelatin, casein,
Natural or semi-synthetic resins such as starch and soybean protein; terpene resins; ketone resins; rosin, rosin esters, and the like can be used. When used in combination with the intermediate layer, it is preferable to select one that can swell in the same solvent as the intermediate layer resin.

The means for forming such an adhesive layer on a hydraulic transferable image is not particularly limited, but
Gravure coat, offset gravure, roll coat,
Means such as bar coating, spray coating, and ultrasonic coating can be used. When forming the adhesive layer,
The resin may be formed by dissolving the above resin or the like in an appropriate solvent.
Further, the thickness of the adhesive layer varies depending on the type of the material of the adhesive layer, but is preferably in the range of ^{2 to} 30 g / m ² .

(3) Method of Manufacturing Curved Printed Body Next, an example of a method of manufacturing a curved printed body using the above-described transfer film for curved printing will be described with reference to the drawings.

(Application of Activator) In order to manufacture a curved printing body, first, an activator is applied, if necessary, to the side of the transfer film for curved printing 1 on which the hydraulic pressure transferable image 4 is provided.
Here, when an adhesive layer is formed on the hydraulic transferable image 4, an activator is applied on the adhesive layer.

The activator is applied in this manner unless the activator is applied to swell the layer of the hydraulic transfer image or the like, and then the transfer film for curved printing is floated on the solvent to swell. In this case, the layer of the liquid pressure transferable image cannot follow the elongation of the support film, and the image may be broken. In addition, when the printing medium is pressed against the transfer film for curved printing from above and transferred, the transfer film for curved printing cannot be in close contact with the surface of the printing medium, and transfer is not successful. When such an activator is applied, if the swelling accelerator present in the layer of the hydraulic transfer image is soluble in the activator, the swelling accelerator can be easily liquefied. As a result, it is possible to more effectively prevent defects such as image breakage of the hydraulic transfer image.

Such an activator may be any as long as it can swell at least one of the layer of the hydraulic transfer image, the intermediate layer and the adhesive layer, and is contained in the layer of the hydraulic transfer image. It does not dissolve the colorant particles, does not evaporate until the transfer takes place, further erodes the surface of the substrate, or when the substrate is undercoated with paint, rapidly contacts the paint when transferring. It is desirable that they do not dissolve in water. Furthermore, from the above-mentioned reason, it is preferable that the swelling accelerator contained in the toner forming the hydraulic transfer image can be dissolved.

Examples of such an activator include, for example, pentane, hexane, heptane, octane and the like, or a mixture thereof, such as gasoline, petroleum, benzene, mineral spirits, aliphatic hydrocarbons such as petroleum naphtha, and benzene. , Toluene, xylene, cyclohexane, ethylbenzene, etc., aromatic hydrocarbons, trichloroethylene, perchlorethylene, chloroform, halogenated hydrocarbons such as carbon tetrachloride, methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, amyl alcohol , Monohydric alcohols such as benzyl alcohol,
Ethylene glycol, propylene glycol, polyhydric alcohols such as glycerin, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl cyclohexanone, ketones such as isophorone, ethyl ether, isopropyl ether, ethylene glycol, monomethyl ether, ethylene glycol, Mono-ethyl ether, ethers such as diethylene glycol, acetates, esters such as butyrate,
Examples include nitrohydrocarbons, nitriles, amines, other acetals, acids, furans, and the like, which are used alone or as a mixed solvent.

In addition, a solvent obtained by adding a resin having an affinity for the solvent to such a solvent can be used as the activator. Such resins include, for example, vinyl chloride, vinyl halide monomers such as vinylidene chloride, styrene and derivatives thereof, vinyl ester monomers such as vinyl acetate, allyl alcohol and allyl esters, acrylic acid, methacrylic acid, N- of unsaturated carboxylic acids such as itaconic acid, crotonic acid, maleic acid or fumaric acid, ester derivatives of the above unsaturated carboxylic acids, nitrile derivatives or acid amide derivatives, and N- of the acid amide derivatives of the above unsaturated carboxylic acids Methylol derivatives and N-alkyl methylol ether derivatives, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, vinyl isocyanate, allyl isocyanate, 2-hydroxyethyl-acrylate,
2-hydroxyethyl-methacrylate, 2-hydroxypropyl-acrylate, 2-hydroxypropyl-
Methacrylate, ethylene glycol-monoacrylate, ethylene glycol-monomethacrylate, ethylene glycol-diacrylate, ethylene glycol-
Dimethacrylate, maleic anhydride, itaconic anhydride,
Thermoplastic resins such as homopolymers or copolymers of monomers such as methyl vinyl ketone, butadiene ethylene, propylene, dimethylaminoethyl methacrylate, vinylpyridine, tert-butylaminoethyl methacrylate, and monoallyl ether of polyhydric alcohols , Polyamide-based resins, polyester-based resins, phenol-based resins, melamine-based resins, urea resins, epoxy-based resins, diallyl phthalate-based resins, silicon resins, thermosetting resins such as polyurethane-based resins, or modified resins or initial resins thereof Condensate, natural resin, rosin and its derivatives, cellulose derivatives,
Natural or synthetic rubber, petroleum resin and the like can be mentioned.

These resins are preferably added to the above-mentioned solvents to form an activator for reasons such as easy viscosity adjustment, irrespective of application method, long toner holding time and long transfer time. The amount of addition is preferably in the range of 5 to 60% by weight.

As a means for applying such an activator, gravure coat, offset gravure, roll coat, bar coat, spray coat, ultrasonic coat and the like can be applied, and the amount of activator applied is ^{2 to} 30 g / m ^2. And preferably 3 to 15 g / m ² .

In the present invention, it is particularly preferable that the swelling accelerator in the toner is soluble in the above-mentioned activator.
When insoluble, it is preferable that the temperature of the activator to be applied is set to the melting point of the swelling accelerator in the toner or more, and the swelling accelerator is melted immediately after application.

(Transfer Processing Step) Next, the transfer film for curved surface printing coated with the activator is floated on a solvent, preferably on water. This state is shown in FIG. The transfer film for curved surface printing 1 on which the hydraulic pressure transferable image 4 constituting the picture is printed on the support film 2 is floated on a solvent. At this time, the temperature of the predetermined solvent is set to a temperature higher than the melting point of the swelling accelerator contained in the toner forming the hydraulic transfer image 4 as necessary. By setting the temperature of the predetermined solvent to a temperature higher than the melting point of the swelling accelerator, the swelling accelerator contained in the layer of the hydraulic transferable image 4 is melted and liquefied, and When the layer No. 4 expands and spreads due to the swelling of the support film 2, aggregation of the toner forming the layer of the hydraulic transferable image 4 can be prevented, and problems such as image cracking can be prevented. Can be.

Since the support film 2 swells in this solvent, the support film 2 swells and spreads as shown in FIG. At this time, the layer of the hydraulic pressure transferable image 4 on the support film 2 also contains the liquefied swelling accelerator as described above and is further coated with an activator. Spread as well. Thereby, the transfer film 1 for curved surface printing
Is spread.

Then, in the state where the transfer film for curved printing 1 is spread as described above, the printing medium 26 is lowered from above the transfer film for curved printing 1 on the solvent 25 as shown in FIG. A part or the whole thereof is settled in the solvent 25, and the transfer film 1 for curved surface printing is spread and adhered to the surface of the printing medium 26 by the pressure of the solvent 25.

Here, the material to be printed 26 is not particularly limited as long as it is formed of a material to which the layer of the hydraulic transfer image or the adhesive layer of the transfer film for curved surface printing can be adhered. It is not something to be done. Examples of the material that can be used for the printing medium include acrylonitrile-butadiene-styrene (ABS) resin, polystyrene resin, polycarbonate resin, AES resin (ABS resin with improved weather resistance), polypropylene resin,
Polyethylene resin, polyolefin oxide resin, homopolymer such as polyvinyl chloride resin, or synthetic resin consisting of a copolymer or a mixture selected from these, melamine resin, phenol resin, formalin resin, urea resin, cellulose resin, etc. Examples include various synthetic resin molded articles including injection molded articles, extrusion molded articles, hollow molded articles, vacuum molded articles, and the like, as well as metal products, ceramic molded articles, and the like.

[0158] In terms of the form, most forms such as those having a concave portion or a convex portion, those having a flat surface, those having a two-dimensional or three-dimensional curved surface, those having a through hole, and those in a lattice shape are applicable. can do. Further, a material such as wood, stone, or woven fabric having a fine emboss for producing a texture can be applied.

Next, the printing medium 26 is removed from the solvent 25, and the support film 2 is removed. This support film 2
Is removed by removing the solvent 2 as shown in FIG.
It is preferable that the swollen support film is shower-washed using the same solvent as in No. 5 because it is the most efficient.
By performing the shower cleaning in this manner, it is possible to completely remove the support film and also remove stains generated at the time of transfer. The temperature of the solvent, the washing time, and the like vary greatly depending on the solvent used and the support film. For example, when polyvinyl alcohol (PVA) is used as the support film and water is used as the solvent, generally, Washing at a water temperature of 15 to 60 ° C. for about 1 to 10 minutes is preferred.

Then, as shown in FIG. 5D, the printing medium 26 from which the support film has been removed is dried by means such as air blow or a drying oven. After drying, a paint for a protective layer is applied to the printing medium 26 using a coating gun or the like (FIG. 5).
(E)), after the application, the coating is dried in a drying furnace (FIG. 5 (f)) to form a protective layer to obtain a curved print.

Here, the material used for the protective layer may be a thermoplastic resin or a curable resin. Specifically, a thermosetting resin such as a thermosetting acrylic resin, a polyurethane resin, an epoxy resin, a melamine resin, a polyester resin, a prepolymer or oligomer having an ethylenically unsaturated bond in a molecule, or an ethylenically unsaturated molecule in a molecule An ionizing radiation-curable composition comprising a composition containing a monomer having a bond or a mixture thereof as a main component can be exemplified.

Examples of the prepolymer or oligomer having an ethylenically unsaturated bond in the molecule used in the above-mentioned ionizing radiation-curable composition include unsaturated polyesters, polyester acrylates, epoxy acrylates and urethane acrylates. Polyol acrylates, various acrylates such as melamine acrylate, polyester methacrylate, epoxy methacrylate, urethane methacrylate, polyol methacrylate, various methacrylates such as melamine methacrylate, etc., as a monomer having an ethylenically unsaturated bond in the molecule, for example, Styrene monomers such as styrene, α-methylstyrene, methyl acrylate, 2-ethylhexyl acrylate, methoxyethyl acrylate, Acrylates such as butoxyethyl acrylate, butyl acrylate, methoxybutyl acrylate, and phenyl acrylate; methacrylates such as methyl methacrylate, butyl methacrylate, ethyl methacrylate, and propyl methacrylate; acrylamide; methacrylamide; An unsaturated carboxylic acid amide,
2- (N, N-dibenzylamino) ethyl acrylate,
Substituted amino alcohol esters of unsaturated acids such as (N, N-dimethylamino) methyl methacrylate, 2- (N, N-diethylamino) propyl acrylate, ethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate Acrylate,
Polyfunctional compounds such as 1,6-hexanediol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, dipropylene glycol diacrylate, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, diethylene glycol dimethacrylate, and / or in the molecule And polythiol compounds having two or more thiol groups, such as trimethylolpropane trithioglycolate, trimethylolpropane trithiopropionate, and pentaerythritol tetrathioglycolate.

Further, examples of the thermoplastic resin used for the protective layer include nitrified cotton, cellulose acetate, cellulose butyrate, acrylic resin, vinyl chloride resin, vinyl acetate resin, vinyl butyral resin and the like.

[0164]

The present invention will be described in more detail with reference to the following examples.

(Example 1: Production of Mg toner) (1) Varnish solvent replacement step (preparation of resin solution) The following components: Varnish of EHMA-HEMA copolymer resin (EHMA:
2-ethylhexyl methacrylate, HEMA: 2-hydroxyethyl methacrylate, EHMA / HEMA copolymerization ratio: 80/20, weight average molecular weight (Mw): 12
000, solid content concentration: 40% by weight, varnish solvent: toluene / IPA): 50 g ・ Isopar L (manufactured by Exxon): 100 g is put in an eggplant type flask, and the degree of pressure reduction can be adjusted while heating in an oil bath. The mixture was rotated and stirred by a suitable evaporator.
The oil bath was set at 80 ° C., and the varnish solvent was recovered by gradually reducing the degree of vacuum of the evaporator to 50 mmHg, and the varnish solvent was replaced with thermal isoper L. In this manner, the weight ratio of the copolymer resin and Isopar L (copolymer resin / Isoper L) was adjusted to 1: 5,
A heated solution in which the HMA-HEMA copolymer resin was dissolved in Isopar L was obtained.

(2) Granulation process The following components: Magenta pigment (trade name: Novoperm Red)
HF2B01, manufactured by Clariant): 20 g Isopar L (manufactured by Exxon): 260 g is placed in a separable flask and heated to 80 ° C. to prepare a pre-prepared heated mixture in which the pigment is contained in the hot isopar L. did. The heating solution prepared in the above-mentioned varnish solvent replacement step was added to the pre-prepared heating mixture, and the mixture was stirred and held for 3 hours with a single-screw stirrer while the temperature was not lowered. Thereafter, the temperature was gradually lowered to 25 ° C. while continuing stirring (cooling rate: 55 hours over 12 hours).
° C), and the pigment surface was coated with a resin.

(3) Dispersion and Dilution Step After cooling, the mixture was transferred to a mayonnaise bottle, 400 g of glass beads were added, and the mixture was dispersed in a paint shaker for 6 hours. After dispersing the beads, the glass beads were removed, Isopar L was added, and the mixture was diluted to a total amount of 2000 g. Finally, basic barium petronate (BBP) is added to the diluted mixture 200 to negatively charge the Mg toner.
It was added in a ratio of 1.8 g to 0 g to obtain a wet developer of Mg toner.

Example 2 Production of Ye Toner First, the composition of the varnish and the electrically insulating dispersion medium was as follows: EHMA-HEMA copolymer resin varnish (EHMA:
2-ethylhexyl methacrylate, HEMA: 2-hydroxyethyl methacrylate, EHMA / HEMA copolymerization ratio: 85/15, weight average molecular weight (Mw): 10
5,000, solid content concentration: 40% by weight, varnish solvent: toluene / IPA): 50 g Isopar L (manufactured by Exxon): 40 g, and the final weight of the copolymer resin and Isopar L The ratio (copolymer resin / Isoper L) is 1: 2
EHMA-H in the same manner as in Example 1 except that
A heated solution in which the EMA copolymer resin was dissolved in Isopar L was obtained.

Next, the composition of the pigment and the electrically insulating dispersion medium was as follows: Yellow pigment (trade name: Seika First Yellow M,
Granulation was carried out in the same manner as in Example 1 except that a pre-prepared heated mixture was prepared by changing to 20 g and Isopar L (manufactured by Exxon): 320 g. Coated.

Thereafter, basic barium petronate (B
A wet developer of Ye toner was obtained in the same manner as in Example 1 except that the mixing ratio of BP) was 3.0 g with respect to 2000 g of the diluted mixture.

Example 3 Production of Bk Toner First, the varnish and the composition of the electrically insulating dispersion medium were as follows: EHMA-HEMA copolymer resin varnish (EHMA:
2-ethylhexyl methacrylate, HEMA: 2-hydroxyethyl methacrylate, EHMA / HEMA copolymerization ratio: 85/15, weight average molecular weight (Mw): 10
5,000, solid content concentration: 40% by weight, varnish solvent: toluene / IPA): 50 g Isopar L (manufactured by Exxon): 40 g, and the final weight of the copolymer resin and Isopar L The ratio (copolymer resin / Isoper L) is 1: 2
EHMA-H in the same manner as in Example 1 except that
A heated solution in which the EMA copolymer resin was dissolved in Isopar L was obtained.

Next, the composition of the pigment and the electrically insulating dispersion medium was changed as follows: Black pigment (trade name: Black Pearl L, manufactured by Cabot): 20 g Isopar L (manufactured by Exxon): 320 g Granulation was carried out in the same manner as in Example 1 except that a preliminarily prepared heating mixture was prepared, and the pigment surface was coated with a resin.

Thereafter, basic barium petronate (B
A wet developer of Bk toner was obtained in the same manner as in Example 1 except that the blending ratio of BP) was 1.0 g with respect to 2000 g of the diluted mixture.

Example 4 Production of Cy Toner First, the varnish and the composition of the electrically insulating dispersion medium were as follows: Varnish of EHMA-HEMA copolymer resin (EHMA:
2-ethylhexyl methacrylate, HEMA: 2-hydroxyethyl methacrylate, EHMA / HEMA copolymerization ratio: 85/15, weight average molecular weight (Mw): 77,
000, solid content concentration: 40% by weight, varnish solvent: toluene / IPA): 50 g Isopar L (manufactured by Exxon): 40 g, and the final weight ratio of the copolymer resin and Isopar L ( 1: 2 copolymer resin / Isoper L)
EHMA-H in the same manner as in Example 1 except that
A heated solution in which the EMA copolymer resin was dissolved in Isopar L was obtained.

Next, the composition of the pigment and the electrically insulating dispersion medium was changed as follows: Cyan pigment (trade name: PB-4806, manufactured by Bayer): 20 g Isopar L (manufactured by Exxon): 320 g Granulation was carried out in the same manner as in Example 1 except that a pre-prepared heated mixture was prepared, thereby coating the pigment surface with a resin.

Thereafter, basic barium petronate (B
A wet developer of Cy toner was obtained in the same manner as in Example 1 except that the mixing ratio of BP) was 2.0 g with respect to 2000 g of the diluted mixture.

Comparative Example 1 Production of Mg Toner A varnish of EHMA-HEMA copolymer resin (EHMA: 2-ethylhexyl methacrylate, HE
MA: 2-hydroxyethyl methacrylate, EHMA
/ HEMA copolymerization ratio: 95/5, weight average molecular weight (M
w): 80,000, solid content concentration: 40% by weight, varnish solvent: toluene / IPA), and a wet developer of Mg toner was obtained in the same manner as in Example 1.

(Comparative Example 2: Production of Mg toner) A varnish (EHMA-MA copolymer resin) of the same amount (EH
MA: 2-ethylhexyl methacrylate, MA: methacrylic acid, EHMA / MA copolymerization ratio: 85/15, weight average molecular weight (Mw): 70,000, solid content concentration: 40
Wt%, varnish solvent: toluene / IPA) was used in the same manner as in Example 1 to obtain a wet developer of Mg toner.

(Comparative Example 3: Production of Mg toner) The following components: Magenta pigment (trade name: Novoperm Red)
HF2B01 (manufactured by Clariant): 20 g-Varnish of EHMA-MMA copolymer resin (EHMA: 2)
-Ethylhexyl methacrylate, MMA: methyl methacrylate, EHMA / MMA copolymerization ratio: 70/30,
Solid content: 40% by weight, varnish solvent: Isopar):
100 g Isopar L (manufactured by Exxon): 260 g is put in a mayonnaise bottle, and 400 g of glass beads are added.
The mixture was dispersed in a paint shaker for 3 hours. After dispersing the beads, the glass beads were removed, Isopar L was added, and the mixture was diluted to a total amount of 2000 g. Finally, Mg
In order to negatively charge the toner, basic barium petronate (BBP) was added to the diluted mixture at a rate of 1.
It was added at a rate of 8 g to obtain a wet developer of Mg toner.

(Evaluation Method) (1) Manufacturability A: The toner is easily dispersed without agglomeration during granulation. ：: Although the particles become slightly larger during granulation, they can be easily redispersed by bead dispersion or the like. X: The toner aggregates during granulation and cannot be easily redispersed (printing cannot be performed).

(2) Thermal transferability ：: In the electrophotographic method as shown in FIG. 9, thermal transfer is performed from a photosensitive drum to a support (PVA film) of a transfer film for curved surface printing via an intermediate transfer member (surface is a silicone resin). Sometimes, thermal transfer failure does not occur at all. Δ: In the same electrophotographic method as described above, the rate of thermal transfer failure (that is, the area ratio of a portion of the image to be transferred that was not transferred to the PVA film and remained on the intermediate transfer member) was less than 50%. . X: In the same electrophotographic method as described above, the rate of occurrence of thermal transfer failure is 50% or more.

(3) Image density A: OD value is 1.0 or more. Δ: OD value is 0.5 or more and less than 1.0. X: OD value is less than 0.5.

(4) Unevenness and Flow A: There is no image unevenness and flow. X: Image unevenness and flow occur.

(5) Hydraulic transferability A: The transfer film for curved printing obtained by the electrophotographic method as shown in FIG. 9 is easily swollen by the activator.

The evaluation results of the above items are shown in the following table. In the table, "-" indicates that evaluation was not performed afterwards because a bad result was obtained in an evaluation item at an early stage.

[0186]

[Table 1]

[0187]

According to the present invention, there is provided a wet developer in which toner particles obtained by coating colorant particles with a copolymer resin are well dispersed. In particular, in the case of manufacturing by a cooling granulation method, it is possible to obtain a wet developer excellent in dispersibility despite containing a very large amount of colorant particles, and the polarity and charge amount of the toner particles are also high. Good reproducibility. Also, when negatively charged toner particles are required (for example,
In the case of applying to an electrophotographic method having a general organic photoreceptor), toner particles are formed by a cooling granulation method, and neutral or basic petronate (particularly basic barium petronate) is used as a charge control agent. By using this, a wet developer having good negative chargeability can be obtained with good reproducibility.

Using the wet developer according to the present invention, a printing method utilizing electrostatic action such as electrostatic transfer, electrostatic recording, electrostatic printing, and the like, is used to transfer the liquid transferability onto a support film of a transfer film for curved surface printing. An image can be formed. The wet developer of the present invention is applicable to an on-demand printing method such as an electrophotographic method among printing methods utilizing an electrostatic action, and is a transfer film for curved surface printing having a desired hydraulic transferable image. Can be formed quickly and easily without using a printing plate. Therefore, the productivity is high, and it is possible to quickly respond to requests such as trial production at the development stage, preparation of samples for presentation, and launch of products of various types and small quantities.

In addition, an electrostatic latent image is formed on the surface of the dielectric,
When the electrostatic latent image is developed using the wet developer of the present invention, and the obtained visible image is transferred to a support film of a transfer film for curved surface printing, excellent transferability and a high-density hydraulic transferability image can be obtained. . Therefore, the wet developer of the present invention exhibits excellent printability for on-demand printing systems such as electrophotography.

Furthermore, when a transfer film for curved surface printing is floated on a solvent, a hydraulic transferable image formed using the wet developer of the present invention can sufficiently expand and spread in accordance with the swelling of the support film. Therefore, it is possible to perform curl-fit curved surface printing without causing cracks.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a transfer film for curved surface printing provided by the present invention.

FIG. 2 is a schematic diagram illustrating an example of an electrophotographic system capable of printing a transfer film for curved surface printing.

FIG. 3 is a schematic diagram illustrating an example of a developer supply unit.

FIG. 4 is a schematic diagram illustrating an example of a developer supply unit.

FIG. 5 is a schematic diagram illustrating an example of curved surface printing by curl fitting.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Transfer film for curved surface printing 2 ... Support film 3 ... Intermediate layer 4 ... Hydraulic transferable image 5 ... Adhesive layer 6 ... Printing system 7 ... Latent image carrying means 8 ... Electric charge removing and cleaning means 9 ... Latent image forming means 10 ... Developing means 11 ... Output means 12 ... Photosensitive drum 12a ... Side section 12b ... Center axis 13 ... Blade 14 ... Large exposure apparatus 15 ... Corona discharge apparatus 16 ... Laser light irradiation apparatus 17 ... Developing roller 17a ... Side section 17b ... Center axis 18 ... reversing roller 19 ... storage tank 20 ... wet developer 21 ... intermediate transfer body 21a ... side surface 21b ... central axis 22 ... impression cylinder 23 ... developing electrode 24 ... minute interval 25 ... solvent 26 ... printing medium

[Procedure amendment]

[Submission date] June 1, 2001 (2001.6.1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction contents]

The molecules of the copolymer resin used in the present invention include, as essential constituent units, a first monomer unit having an affinity for an electrically insulating dispersion medium derived from 2-ethylhexyl methacrylate (EHMA), and a 2-hydroxy compound. A second monomer unit having colorant particle affinity derived from ethyl methacrylate (HEMA). The toner particles of the wet developer mainly include the second particles around the colorant particles.
A core portion to which HEMA which is a monomer unit is adsorbed and which is insoluble in the electrically insulating dispersion medium, and a periphery of the core portion which is mainly wrapped by EHMA which is the first monomer unit, and Since it is composed of the outer edge portion that dissolves or swells, the colorant particles in the core portion are prevented from approaching each other in the electrically insulating dispersion medium, and exhibit good dispersibility.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0052

[Correction method] Change

[Correction contents]

In the present invention, a pigment having an average particle size of 0.1 to 100 μm in the secondary aggregation state is usually used as the colorant particles. The pigment can be included in the toner particles in a P / V ratio (pigment weight / resin weight) of up to 3/1, preferably up to 2/1. The wet developer of the present invention hardly causes problems such as macroscopic aggregation even when a large amount of toner particles are contained, so that the pigment content can be drastically increased.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0055

[Correction method] Change

[Correction contents]

In the molecule of the copolymer resin used in the present invention, as essential constituent units, a first monomer unit having an affinity for an electrically insulating dispersion medium derived from 2-ethylhexyl methacrylate (EHMA); A second monomer unit having colorant particle affinity derived from ethyl methacrylate (HEMA). The copolymer resin covers the colorant particles by adsorbing to the surface of the colorant particles via the portion of the second monomer unit in the molecular structure, thereby forming toner particles. The obtained toner particles mainly consist of a core portion in which HEMA as the second monomer unit is adsorbed around the colorant particles and are insoluble in the electrically insulating dispersion medium, and the periphery of the core portion is mainly the above-mentioned. Since it is composed of the outer peripheral portion which is wrapped by the first monomer unit, EHMA, and which dissolves or swells in the electrically insulating dispersion medium, in the electrically insulating dispersion medium, the colorant particles in the core portion are prevented from approaching each other. Rare and show good dispersibility.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0100

[Correction method] Change

[Correction contents]

Next, in the step of cooling the heated mixture, the prepared heated mixture is cooled with stirring to precipitate (granulate) the toner particles. It is preferable to cool the heated mixture gradually rather than rapidly. The cooling rate affects the particle size of the toner particles and aggregation between the toner particles. The cooling rate tends to be large when the cooling rate is increased, and tends to be small when the cooling rate is reduced. The cooling performed gradually may be performed at least between the temperature at which the copolymer resin in the heated mixture starts to precipitate and the temperature at which the precipitation of the copolymer resin stops, and is equal to or higher than the temperature at which the copolymer resin starts to precipitate or the precipitation stops. When the temperature is lower than the required temperature, the cooling is not necessarily required. The slow cooling rate varies depending on the electric insulating dispersion medium used, the copolymerization ratio of the copolymer resin, and the like, but in many cases, the rate is preferably in the range of −20 ° C./hour to −2 ° C./hour. If the cooling rate is less than -2 ° C / hour, the work efficiency is deteriorated, which is not practical. On the other hand, -20 ° C / h
If the cooling rate exceeds our, rapid granulation occurs, so that the toner characteristics are likely to deteriorate.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

(3) Dispersion and Dilution Step After cooling slowly, the mixture was transferred to a mayonnaise bottle, 400 g of glass beads were added, and the mixture was dispersed in a paint shaker for 6 hours. After dispersing the beads, the glass beads were removed, Isopar L was added, and the mixture was diluted to a total amount of 2000 g. Finally, basic barium petronate (BBP) is added to the diluted mixture 200 to negatively charge the Mg toner.
It was added in a ratio of 1.8 g to 0 g to obtain a wet developer of Mg toner.

Continued on the front page (72) Inventor Yang Mayumi 311 Takemazawa, Miyoshi-cho, Iruma-gun, Saitama F-term (reference) in Dainippon Total Process Building Co., Ltd. 2H069 AA01 BA01 CA03 CA27 CA30 DA05 DA08 3B005 FB40 GA24 GC03

Claims (30)

[Claims] 1. A wet developer in which toner particles obtained by coating colorant particles with a copolymer resin are dispersed in an electrically insulating dispersion medium, wherein the copolymer resin is derived from 2-ethylhexyl methacrylate. At least a first monomer unit having an affinity for an electrically insulating dispersion medium and a second monomer unit having an affinity for a colorant particle derived from 2-hydroxyethyl methacrylate, wherein the first monomer unit and the second monomer A wet developer for forming a hydraulic transfer image, wherein a copolymerization ratio of units (first monomer unit / second monomer unit) is 90/10 to 70/30 by weight. 2. The wet developer according to claim 1, wherein the copolymer resin is a 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymer resin. 3. The copolymer resin having a weight average molecular weight of 5
000 to 150,000,
The wet developer according to claim 1. 4. The wet developer according to claim 1, wherein the weight ratio of the colorant particles to the copolymer resin (colorant particles / copolymer resin) is 1/3 to 3/1. . 5. The wet developer according to claim 1, wherein the charge control agent contains at least neutral or basic metal petronate, and the toner particles are negatively charged. 6. The wet developer according to claim 1, wherein the electrically insulating dispersion medium is a branched aliphatic hydrocarbon. 7. A yellow pigment as the colorant particles,
A cyan pigment, a magenta pigment or a black pigment is used, and the copolymerization ratio of the first monomer unit to the second monomer unit is 85/15 to 80/20 and the weight average molecular weight is 70,000 to The wet developer according to claim 1, wherein 130,000 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymer resin is used. 8. The method for producing a liquid transferable image forming wet developer according to claim 1, wherein the colorant particles are contained in a heated electrically insulating dispersion medium. And a first monomer unit having an affinity for an electrically insulating dispersion medium derived from 2-ethylhexyl methacrylate and a second monomer unit having an affinity for a colorant particle derived from 2-hydroxyethyl methacrylate. A copolymer resin having at least a composition ratio of the first monomer unit and the second monomer unit (first monomer unit / second monomer unit) of 90/10 to 70/30 by weight is dissolved. A method for producing a wet type developer, wherein toner particles are granulated by cooling the heated mixture while stirring. 9. The wet developer according to claim 8, wherein the granulation is completed by adding an electrically insulating dispersion medium and continuing stirring during or after cooling the heated mixture. Production method. 10. The method according to claim 8, wherein the heating mixture is heated to 80 ° C. or higher. 11. The cooling rate of the heating mixture is 2 ° C./h.
The method for producing a wet developer according to claim 8, wherein the temperature is 20 to 20C / h. 12. At least one of neutral and basic metal petronate as a charge control agent is added to the wet developer or an intermediate product thereof at any stage during or after the manufacture of the wet developer. By
The method for producing a wet developer according to claim 8, wherein the toner particles are negatively charged. 13. The method according to claim 8, wherein a branched aliphatic hydrocarbon is used as the electrically insulating dispersion medium. 14. A colorant particle comprising a yellow pigment, a cyan pigment, a magenta pigment or a black pigment, and the copolymer resin having a copolymerization ratio of a first monomer unit and a second monomer unit of 85/15. ~ 80 /
20 and a weight average molecular weight of 70,000 to 130,0
The method for producing a wet developer according to claim 8, wherein a 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymer resin of No. 00 is used. 15. A method for producing a liquid developer for forming a liquid transferable image according to claim 1, wherein the dispersion medium is derived from 2-ethylhexyl methacrylate. At least a first monomer unit having a hydrophilic property and a second monomer unit having an affinity for colorant particles derived from 2-hydroxyethyl methacrylate, and a copolymerization ratio of the first monomer unit and the second monomer unit (the second monomer unit). 1 monomer unit / second monomer unit) in a weight ratio of 9
By heating a mixture containing at least a varnish containing a copolymer resin of 0/10 to 70/30 and an electrically insulating dispersion medium under reduced pressure, the varnish solvent is removed from the mixture, and the mixture is heated. By adding the colorant particles to the mixture at any stage before, during or after the decompression / heating, the colorant particles are contained in the heated electrically insulating dispersion medium and the copolymer resin A method for producing a wet developer, comprising preparing a heated mixture in which is dissolved, and cooling the heated mixture while stirring to granulate toner particles. 16. The wet developer according to claim 15, wherein the granulation is completed by adding an electrically insulating dispersion medium during or after cooling the heated mixture and continuing stirring. Production method. 17. The varnish solvent is removed by heating a mixture containing at least the varnish and the electrically insulating dispersion medium to 80 ° C. or more while reducing the pressure to 300 to 30 mmHg. 16. The method for producing a wet developer according to 15 above. 18. A varnish solvent is removed by heating a mixture containing at least the varnish and the electric insulating dispersion medium under reduced pressure, so that the copolymer resin dissolves in the electric insulation dispersion medium. Prepare a heating solution consisting of
The method according to claim 15, wherein the colorant particles are added to the obtained heating solution in a state of a preliminarily prepared heating mixture in which the colorant particles are contained in a heated electrically insulating dispersion medium. 3. The method for producing a wet developer according to item 1. 19. At least one of neutral and basic metal petronate as a charge control agent is added to the wet developer or an intermediate product thereof at any stage during or after the manufacture of the wet developer. By
The method according to claim 15, wherein the toner particles are negatively charged. 20. The method according to claim 15, wherein a branched aliphatic hydrocarbon is used as the electrically insulating dispersion medium. 21. A yellow pigment, a cyan pigment, a magenta pigment or a black pigment is used as the colorant particles, and the copolymerization ratio of the first monomer unit to the second monomer unit is 85/15. ~ 80 /
20 and a weight average molecular weight of 70,000 to 130,0
The method for producing a wet developer according to claim 15, wherein a 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymer resin of No. 00 is used. 22. A liquid transferable image formed on one surface of a support film swelling in a predetermined solvent by using the wet developer according to claim 1. Transfer film for curved printing. 23. The liquid-pressure transferable image described above, wherein (A) an electrostatic latent image is formed and carried on a surface of a dielectric, and (B) the electrostatic latent image is formed by the electrostatic latent image. And (C) transferring the developed image to one surface of a support film that swells in a predetermined solvent. 23. The transfer film for curved surface printing according to 22. 24. In order to form the hydraulic transferable image, an image developed on the surface of the dielectric is transferred to a surface of an intermediate transfer body and temporarily transferred, and then the intermediate transfer is further performed. 24. The transfer film for curved printing according to claim 23, wherein the transfer film is thermally transferred from a surface of the body to one surface of a support film which swells in a predetermined solvent. 25. In order to form the hydraulic transferable image, an electrostatic latent image having a negative charge is formed and carried on the surface of the dielectric, and a negative latent image is formed on the surface carrying the electrostatic latent image. The transfer film for curved surface printing according to claim 23, wherein the reversal development is performed by supplying the charged wet developer to the surface. 26. In order to form the hydraulic transferable image, a photosensitive conductor which temporarily exhibits conductivity only in an exposed portion is used as the dielectric, and the surface thereof is exposed imagewise. The transfer film for curved surface printing according to claim 25, wherein an electrostatic latent image is formed. 27. A method for producing a transfer film for curved surface printing, comprising at least the following steps. (A) a step of forming and carrying an electrostatic latent image on the surface of a dielectric, (B) a step of developing the electrostatic latent image using the wet developer according to any one of claims 1 to 7; And (C)
Transferring the developed image to one surface of a support film that swells in a predetermined solvent to form a hydraulically transferable image. 28. A support in which the image developed on the surface of the dielectric is transferred to the surface of an intermediate transfer member to temporarily carry the image, and then swells in a predetermined solvent from the surface of the intermediate transfer member. The method for producing a transfer film for curved surface printing according to claim 27, wherein a hydraulic transferable image is formed by thermal transfer onto one surface of the film. 29. A negatively charged electrostatic latent image is formed and carried on the surface of the dielectric, and the negatively charged wet developer is supplied to the surface carrying the electrostatic latent image to perform reversal development. The method for producing a transfer film for curved surface printing according to claim 27, wherein the method is performed. 30. An electrostatic latent image is formed by exposing a surface of the photosensitive conductor that temporarily exhibits conductivity only to an exposed portion as the dielectric, and exposing the surface of the photosensitive conductor to an image.
A method for producing the transfer film for curved surface printing according to claim 29.