JPH1078675A - Crosslinked and fixed toner image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a toner image having improved resistance to external influence. SOLUTION: Toner particles each contg. a reactive group (RGA) are imagewise deposited on a substrate contg. a reactive group (RGB) and the reactive group RGA is allowed to react with the reactive group RGB to harden the toner particles. The reactive groups RGA, RGB are selected from among epoxy, aldehyde, hydroxyl, carboxyl, mercapto, amino and amido groups so that a reaction pair is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a method for forming a toner image in which the toner image is strongly bonded to a substrate and is very resistant to abrasion.

[0002]

BACKGROUND OF THE INVENTION For example, electro (photo) graphy,
In the case of image forming methods such as magnetography and ionography, a latent image is formed, which is developed by attracting so-called toner particles. The later developed latent image (toner image) is transferred onto the final substrate and fused to this substrate. In the case of DEP, so-called toner particles are deposited image-wise directly on the final substrate and fused to this substrate.

[0003] Toner particles are basically polymer particles containing a polymer resin as a main component and various components mixed with the toner resin. Apart from the colorless toner used, for example, for finishing functions, the toner resin contains at least one black and / or coloring substance, for example a coloring pigment.

[0004] In the various imaging methods described above, the toner particles can be present in a liquid or dry developer composition.

In most cases, it is preferred to use a dry developer composition. The main advantage of using a dry developer composition is that there is no need to remove the liquid phase after development.
The absence of evacuation of (mainly organic) liquids is desirable from both economic and ecological perspectives.

However, in all processes using dry particulate material to form an image, very often the image is deposited on a substrate by applying the particulate marking elements as multiple superimposed layers. . The problems with the multiply superposed layers of marking particles, which are fixed in some way on the substrate, vary not only with regard to the quality of the image, but also with respect to the stability of the image and the mechanical issues.

For example, EP-A 471 894, EP-
A 554 981, US 4,828,950 and U
S 4,885,603 disclosed the application of a layer of transparent toner particles over the toner image to provide better resistance to physical damage. Other means and methods have been proposed for forming toner images that are very resistant to external influences (eg, mechanical influences, heat, contact with solvents, etc.).

For example, in US Pat. No. 3,723,114, the problem of storability of a fused toner image has been proposed, and the main problem is that the toner image becomes sticky after storage depending on storage conditions. The problem has been solved by using a substantial proportion of the thermosetting polymer in the toner resin.

The use of photo-curable toners is described, for example, in U.S. Pat.
S 5,470,683, giving a toner image with better weatherability. That application provides a capsule toner having a core containing a polymerizable compound, a polymerization initiator and other conventional toner components. The wick is surrounded by a hard shell, which is broken during the settling phase. After the fixing step, the polymerizable compound is polymerized by low energy visible light in this particular disclosure. Although the description of these disclosures produces a toner layer that is not easily damaged, the nature of the solution itself limits the variety of resins that can be used to make the toner. Accordingly, further improvements along the lines of the disclosure cited above are desirable.

[0010]

OBJECTS AND SUMMARY OF THE INVENTION An object of the present invention is to eliminate the need to insert a limited number of specific toner resins into toner particles.
It is to provide a method for the formation of a toner image that is very resistant to external physical influences.

It is a further object of the present invention to provide a method for forming a toner image in which the toner image is very resistant to the effects of common organic solvents.

It is another object of the present invention to provide a method for forming a toner image in which the toner image is strongly bonded to a toner receiving substrate.

It is a further object of the present invention to provide a method for forming a toner image that is very weather resistant.

Further objects and advantages of the present invention will become clear from the detailed description hereinafter.

[0015] It is an object of the present invention in the first embodiment of the present invention, wherein: i) preparing a substrate containing a reactive group RGB; ii) preparing toner particles containing a reactive group RGA; iii) on the substrate Iv) reacting the reactive groups RGA with the reactive groups RGB to form a toner image on the substrate, comprising the step of curing the toner particles. Is provided by providing a method for

[0016] It is an object of the present invention in a second embodiment of the present invention to provide: i) providing toner particles comprising a reactive group RGA; ii) depositing said toner particles image-wise on said substrate. Iii) applying a compound comprising a reactive group RGB onto the image, and iv) reacting the reactive group RGA with the reactive group RGB to cure the toner particles. Of the present invention is provided by providing a method for forming a toner image.

[0017]

DETAILED DESCRIPTION OF THE INVENTION By curing (fused) toner particles contained in an image, external influences (ie, mechanical abrasion, thermal decomposition, attack by organic solvents, weather, etc.) are obtained.
It has been found that it is possible to produce a toner image on a substrate with a high degree of resistance to This curing converts the reactive groups RGA present in the toner particles into the reactive groups RG.
The reaction is performed by curing the toner particles by reacting with B. This curing can be carried out via two ways: in the first, the toner particles contain the reactive groups RGA, the substrate contains the reactive groups RGB, and both reactive groups interact with each other. To be chosen. In the second method, a so-called "crosslinker" or "curing" agent containing reactive groups RGB is applied on the toner image and reacted with the reactive groups RGA contained in the toner particles. Although both methods provided toner images that were very resistant to mechanical effects as such, it is within the scope of the present invention to combine both methods to further improve the hardness and mechanical resistance of the toner image. it can. In the context of the present invention, "image on substrate"
Means a substrate having a human-readable or / and machine-readable statement, a substrate having a figure, a substrate having a photograph (both color and monochrome), and a substrate having a combination of at least two of the above. I do.

[0018]

FIRST EMBODIMENT OF THE INVENTION In a first embodiment of the present invention, a specific chemical interaction between the toner particles and the substrate is used to couple the toner image and / or between the toner image and the substrate. Strengthen the mechanical strength of

We provide toner particles containing reactive groups (RGA) and react these reactive groups (RGA) with the reactive groups (RGB) present in the substrate,
It has been found that the disadvantages of previous methods for providing mechanically strong toner images can be overcome. After the reaction, the toner particles are cross-linked and / or chemically bonded to the substrate. In the following, the terms "harden" and terms derived therefrom are used to mean crosslinking and / or chemically fixing the toner particles to the substrate.

Preferably, both the reactive group RGA and the reactive group RGB are members selected from the group consisting of an epoxy group, an aldehyde group, a hydroxyl group, a carboxyl group, a mercapto group, an amino group and an amide group. The reactive groups RGA and RGB are preferably selected to form a reactive pair that reacts easily (ie, relatively quickly at relatively low temperatures). Both reactive groups (RGA and RGB) can be part of a polymer, oligomer or low molecular weight (less than 2000) molecule. The molecule carrying the reactive group RGA and the reactive group RGB can carry one or more of these reactive groups. The toner particles and / or the substrate can, if desired, comprise a mixture of compounds bearing reactive groups. For example, the toner particles can include a compound that includes a hydroxyl group, along with a compound that includes an epoxy group. In the substrate, various compounds having a reactive group can also be present.
It may be useful to mix a polymer compound containing a reactive group with a low molecular weight compound containing a reactive group. Reactive groups (R
The reaction between GA and RGB) results in crosslinking of the toner particles, chemical fixing of the toner particles to the substrate, or both crosslinking of the toner particles and their chemical fixing to the substrate. The type of reaction that takes place (crosslinking or chemical anchoring) depends on the nature of the compound bearing the reactive group. For example, when the reactive group RGA in the toner particles is included in the polymer compound and the reactive group RGB in the substrate is included in, for example, a low molecular weight molecule having two reactive groups RGB, the fusion of the toner particles to the substrate may occur. During deposition, low molecular weight molecules can migrate from the substrate and crosslink the two polymer compounds bearing the reactive groups RGA present in the toner particles. For example, the reactive group RGA
If both RGB and RGB are included in the polymer compound, the reaction between RGA and RGB during fusing will rather result in chemical fusing of the (fused) toner particles to the substrate. Thus, by careful selection of compounds of different nature (polymers, olagomers or low molecular weight molecules) bearing reactive groups RGA, and also compounds of different properties (polymers, oligomers or low molecular weight molecules bearing reactive groups RGB) By carefully selecting the molecule, the ratio between the crosslinking reaction and the chemical fixing reaction can be adjusted to the required hardness of the toner layer,
And the required strength of fusing of the fused toner particles to the substrate. Reactive group RGA or RGB
Typical, and very useful, reaction pairs in the present invention include: i) an amine number (KOH) of 140-430 mg KOH / g
(Expressed in equivalent weight) and a compound containing an epoxy group. Polyaminoamide resins useful in the present invention are described in Union Camp Corp. Union Camp Chemical, a subsidiary of USA
s Ltd, Bedlington, Northumb
erland NE22 7DH, UK to UNIRE
It is available under the trade name Z. Epoxy groups are advantageously, for example, ARALDITE GT 7203 (Ciba-
Geigy of SWITZERLAND epoxy resin) and EPIKOTE 1004
(A trade name of Shell Company, UK).

Ii) Polymers having an acid number higher than 2.5 mg KOH / g or a hydroxyl number higher than 2.5 mg KOH / g, and compounds bearing epoxy groups as described immediately above.

Iii) The above-mentioned polymer containing an epoxy group and polyaziridines.

Iv) Polymers having an acid number higher than 2.5 mg KOH / g or a hydroxyl number higher than 2.5 mg KOH / g, and polyaziridines.

V) Polymers having an acid number higher than 2.5 mg KOH / g or a hydroxyl number higher than 2.5 mg KOH / g, and polyabietic acid.

Vi) Polymers having an acid number higher than 2.5 mg KOH / g or a hydroxyl number higher than 2.5 mg KOH / g and highly methylated melamine resins.
The latter is American Cyanamid Comp
CYMEL 300, CYME via any USA
L 301, CYMEL 303 and CYMEL 35
It is available under the trade name 0. Examples of polymers that have an acid number greater than 2.5 mg KOH / g or a hydroxyl number greater than 2.5 mg KOH / g and are very useful in the present invention are shown in Table 1.

Vii) A polyamide resin and a curing agent containing an epoxy group.

Viii) A polyester / polyamide copolymer and a curing agent containing epoxy groups.

Is as follows.

The toner particles to be used in the electrostatic printing device preferably have a very high mechanical strength and can withstand mechanical influences (pressure, friction, etc.) in the printing device before and during development. Therefore, it is important that the mechanical strength of the toner particles be preserved. Therefore, the reactive group R
The compound containing GA is preferably a solid that does not reduce the mechanical strength of the toner particles into which it is inserted. Thus, in a preferred embodiment, the reactive group RGA is part of a polymer used as a toner resin (alone or in a mixture with other known toner resins), and the reactive group RGA carries the reactive group RGA. Is ≧ 35 ° C., preferably 4
It preferably has a Tg higher than 0 ° C. Thus, when using the above reaction couple in the first embodiment of the present invention, it is preferable to insert a polymer compound having a reactive group into the toner particles. > 2.5 m, very suitable for use in toner particles used in the method of the invention
gKOH / g acid number and / or> 2.5 mg KOH / g
Polymers having a hydroxyl number of can be polycondensates and addition polymers, typical examples are tabulated in Table 1. The reactive group RGA can be inserted into the toner resin of the toner particles or be part of an epoxy-resin that is the toner resin of the toner particles. Typical examples of useful epoxy resins (polymers) are, for example, ARALDITE
GT 7203 (Switzerland's Ciba-
Geigy's trade name for epoxy resin) and EPI
KOTE 1004 (Shell Company, U
K product name). The compound bearing a reactive group RGA and inserted into the toner particles can be a polyamide resin or a polyester / polyamide copolymer.

[0030]

[Table 1]

* AV: acid value in mgKOH / g resin ** HC: hydroxyl value in mgKOH / g resin + Mn: number average molecular weight (x1000) † Mw: weight average molecular weight (x1000) DIANOL 22 is bis-ethoxylated 2 On 2,2-bis (4-hydroxyphenyl) propane
Herlands AKZO CHEMIE.

DIANOL 33 is the AKZO CHEM of Etherlands for bis-propoxylated 2,2-bis (4-hydroxyphenyl) propane.
This is the IE product name.

The chemical compound (polymer, oligomer or monomolecule) bearing the reactive group RGA is present on the body of the toner particle, on the surface of the toner particle, or on both the body and the surface of the toner particle. be able to.

The toner particles containing a compound having a reactive group RGA in the main body of the particles are produced by melt-kneading a toner component (eg, a toner resin, a charge control agent, a pigment, etc.) and the compound having a reactive group RGA. can do. After melt-kneading, the mixture is cooled, the solidified mass is comminuted and ground, and the resulting particles are fractionated. The "emulsion polymerization" and "polymer emulsion" methods for toner production can also be used to produce toner particles in which a compound having a reactive group RGA is inserted into the body of the toner particles. In the case of the "emulsion polymerization" method, a water-immiscible polymerizable liquid is sheared to form droplets that are emulsified into an aqueous solution, and the polymerization of monomer droplets takes place in the presence of an emulsifier; For example, USP 2,932,629, USP 4,1
48,741, USP 4,314,932 and EP
-A 255 716. In the case of the "polymer emulsion" method, the pre-formed polymer is dissolved in a suitable organic solvent that is immiscible with water, the resulting solution is dispersed in an aqueous medium containing a stabilizer, and the organic solvent is evaporated. ,
Drying the resulting particles; such methods are described, for example, in US
P 4,833,060.

The toner particles having a compound having a reactive group on the surface can be produced as described in EP-A 725 317. In this European application: (i) dissolving at least one organic polymer (toner resin) in a solvent to form a solution that is immiscible with water;
(Ii) dispersing the solution in an aqueous phase to form a dispersion of small droplets; (iii) removing the solvent from the dispersed droplets by evaporation; and (iv) separating the polymer particles from the water in the aqueous phase. Steps; I. The dispersion of the droplets is stabilized by the presence of a dissolved, water-soluble (co) polymer containing hydrophobic and hydrophilic moieties in the aqueous phase; II. A method is disclosed for producing toner particles, wherein, after evaporation of the solvent, the water-soluble (co) polymer is at least partially converted to a water-insoluble compound and precipitates on the solid polymer particles.

Preferred stabilizer (co) polymers are from 50 to
A copolymer of vinyl acetate and crotonic acid having a total acid number of 300 (90/10 by weight);
A copolymer of styrene and maleic anhydride having a total acid number of 00, both of which are stated to be at least partially converted to their ammonium salt form. The water-soluble stabilized (co) polymer is precipitated on the particles produced by the process of the present invention by a chemical reaction, such as acidification of an aqueous medium, and the water-soluble (co) polymer that adheres to the dispersed polymer particles is a particle. It can be converted to a water-insoluble species that precipitates on. By doing so, carboxylic acid groups are present on the surface of the toner particles.

The curing reaction of the present invention (reactive groups RGA and RG
The reaction during B) proceeds readily when the interpenetration between the toner particles and the substrate is very high. In this mutual penetration,
The toner particles on a substrate (between the fixing or with additional heating step after fixing), preferably up to 0.99 ^o, and most preferably reached by heating to a temperature which is up to 120 ° C.. Therefore, 50-2000 at 120 ° C.
It is preferred to use toner particles containing a compound having a reactive group RGA, having a melt viscosity of Pas, preferably 100-1000 Pas. All of the melt viscosities referred to herein are RHEOMETRICS dynamic rheometers, RVEM-200 (One Possumtow).
n Road, Piscataway, NJ 0885
4 USA). The viscosity measurement is performed at a sample temperature of 120 ° C. A sample weighing 0.75 g, one of which is 100 rad / sec and 1
Applies to the measuring gap (about 1.5 mm) between two parallel plates of 20 mm diameter oscillating at an amplitude of 0 ^-3 radians.

The reaction between the reactive groups RGA and RGB is
It can be accelerated by providing a catalyst for this reaction, which is beneficial. The catalyst is preferably an acid (organic or inorganic) or a tertiary amine. Typical examples of suitable catalysts are p-toluenesulfonic acid, trimethylamine and triethylamine. Within the scope of the present invention, the catalyst or catalysts can be inserted into the toner particles, the substrate or both the toner particles and the substrate. The catalyst or catalysts can be inserted into the toner particles as long as the insertion does not reduce the mechanical resistance of the toner particles, ie, the Tg remains above 35 ° C.

The toner particles have a reactive group RGA, for example, not only a member selected from the group consisting of an epoxy group, an aldehyde group, a hydroxyl group, a carboxyl group, a mercapto group, an amino group and an amide group, but also a group capable of being cured by radiation. It is beneficial to include the compound or mixture of compounds retained.

Thus, the present invention provides: i) providing a substrate comprising the reactive groups RGB, i) image-wise depositing toner particles comprising the reactive groups RGA, a UV curable compound and a photoinitiator on the substrate. Ii) fusing the toner particles to the substrate, and fusing;
Forming a cured toner image; and iii) UV curing the UV curable compound. A method for forming a toner image on a substrate. UV-curing can take place online, for example at the melting station itself of the electrostatographic apparatus or at a station directly adjacent to the melting station.

Radiation curing can be performed off-line in another apparatus, in which case the fused toner particle layer is heated again and irradiated with a curing beam.

In order to preserve the mechanical strength of the toner particles, the compounds containing radiation-curable groups to be inserted into the toner particles for use according to the invention are not monomers but are already oligomeric or polymeric compounds. Is preferred. The mixture of the radiation curable compound itself is ≧ 3
As long as it has a Tg of 5 ° C., monomeric compounds can be present in the mixture of radiation-curable compounds. In the present invention, an electron beam-curable group can be used, but a radiation-curable group is preferably curable by UV-light. Radiation curable polymer compounds that are very useful in toner particles for use in the present invention are
≧ 35 as disclosed in P-A 667 381
It is a UV curable solid epoxy resin with a Tg of ° C. In this application, the solid composition (I) comprises: (a) a solid having an Tg higher than 35 ° C., an oligomeric cationically polymerizable polyglycidyl ether or ester (II), or (II) in liquid or crystalline form. A mixture of a monomeric mono-, di- or poly-epoxy resin, or a mixture of (II) and a cyclic acetal; (b) a polyfunctional nucleophilic chain transfer agent; (c) 0.05 to 3% by weight. Of a photoinitiator for cationic polymerization (in terms of the amount of a), and (d) any conventional additives for coating powders. These compositions (I) are melted together and the cooled mixture is ground. Exemplary compositions have a Tg from 65 ° C to 115 ° C or more.

Other useful U for insertion into toner particles
V-curable resins are powders based on unsaturated polyesters and polyurethane acrylates, a typical example of such a polymeric UV-curable system is Hoecht H.
high Chem, Hoechts-Sara Per
o (Mi) It is available via Italy. Such a system has a solid unsaturated polyester resin with a Tg of ≧ 52 ° C. available under the trade name ALFTALAT VAN 1743, and an acrylic functional group with a Tg of ≧ 47 ° C. available under the trade name ADDITOL 03546. Contains urethane adducts. The nature of this system is Eur
opean Coating Journal n ^o
9/95 606-608 (1995). Also useful in the present invention are powders comprising a mixture of a non-acrylate binder system, for example, an unsaturated polyester resin intercalated with maleic or fumaric acid and a polyurethane containing vinyl ether. Such a binder system was developed by the Netherlands DSM resin,
Its properties are European Coating Jou
rnal n ^o 3/96 115-117 (199
6).

In order to carry out UV curing, it is necessary that a photoinitiator be present. Very useful initiators are sulfonium salts such as triarylsulfonium salts, triarylsulfonium hexafluorophosphate, benzophenone and the like. In the context of the present invention, very useful typical photoinitiators are, for example, 2-hydroxy-2-methyl-1-
Phenyl-propan-1-one, compound I, a mixture of compound I and compound II and compound III:

[0045]

Embedded image

The initiator can be inserted into the toner particles together with the UV-curable system or can be inserted into the substrate. This embodiment has the advantage that the resin contained in the fused image is cross-linked (by UV-curing) and binds to the substrate by a chemical bond.

If UV-curable or radiation-curable compounds are used in the first embodiment of the invention, they can be in various combinations: i) UV-curable compounds (or UV A mixture of curable compounds) and a photoinitiator (or a mixture of photoinitiators)
Ii) both the UV-curable compound (or mixture of UV-curable compounds) and the photoinitiator (or mixture of photoinitiators) Inserting the UV-curable compound (or mixture of UV-curable compounds) into the substrate, iii) inserting the UV-curable compound (or mixture of UV-curable compounds) into the toner particles UV-curable compound (or a mixture of UV-curable compounds)
And both a photoinitiator (or a mixture of photoinitiators) are inserted into the substrate; iv) a UV-curable compound (or a mixture of UV-curable compounds) is inserted into the toner particles and the photoinitiator ( Or a mixture of photoinitiators) into the substrate.

Substrates useful in the first embodiment of the present invention include:
Contains reactive groups RGB. This reactive group (RGB) in the substrate useful in the present invention is in principle a member of the same group of reactive groups as the reactive group RGA present in the toner particles;
That is, the reactive groups RGB are epoxy groups, aldehyde groups,
It is preferably a member selected from the group consisting of a hydroxyl group, a carboxyl group, a mercapto group, an amino group and an amide group. The reactive group RGB can be part of a polymer, oligomer or low molecular weight (less than 2000) molecule. Molecules carrying the reactive groups RGB can carry one or more of these reactive groups.

In the present invention, the reactive groups RGB are selected such that they can react with one or more reactive groups RGA present in the toner particles. For example, if hydroxyl and / or carboxyl groups are present in the toner particles, the substrate contains a reactive group that can readily react with the hydroxyl and / or carboxyl groups. Typical examples of such reactive groups are epoxy groups, aldehyde groups, polyaziridine groups and the like. For example, when an epoxy group is present as a reactive group RGA in the toner particles, the substrate preferably contains a hydroxyl, carboxyl, amide or amino group as the reactive group RGB. When the above reaction pair is used, it is preferred to insert a low molecular weight compound or an oligomer or polymer compound having a Tg of <35 ° C. into the substrate. Compounds which possess reactive groups RGB which are thus very suitable for insertion into a substrate include, for example, polyaziridines, polyamidoamine resins, highly methylated melamine resins, hydroxyl-containing epoxy curing agents such as epichlorohydrido Phosphorus and n are 3-10
Of an integer _{HO- (CH 2 -CHOH-CH 2} -O-)
The reaction product of _n- H, epichlorohydrin and n are 3 to 1
HO- (CH _{2) wherein} R is an alkyl group;
—CHOR—CH ₂ —O—) _n —H is a reaction product.
Yet another useful epoxy curing agent is, for example, EP-A
495 314, pages 23-26. Formula A
Epoxy curing agents represented by -1 to A-6 can also be used in the present invention.

[0050]

Embedded image

The compound having a reactive group (RGB) can be included in a toner receiving layer applied to a substrate.
The substrate can be paper, paperboard, plastic film, and the like. The toner receiving layer can include a binder,
Compounds having a reactive group RGB can be embedded in the binder. Useful binders carrying reactive groups RGB include, for example, the same binders already described hereinabove as useful binders for toner particles, ie, an acid number of> 2.5 mg KOH / g and /Or>2.5m
Polymers having a hydroxyl number of gKOH / g (examples of such polymers are in Table 1), as well as epoxy polymers. For example, polymers useful as binders in substrates to be used according to the present invention and capable of reacting with hydroxyl or carboxyl groups (contained in toner particles) include epoxy polymers, polymers bearing aldehyde groups, And polyaziridines. When the toner particles contain epoxy or aldehyde groups, the binder in the image receiving layer of the substrate for use in the present invention preferably contains hydroxyl, carboxyl and / or amino groups. Typical useful binders are gelatin, polyvinyl alcohol and the like. The binder can also include resinous compounds: polyamides in the form of latex, polyesters containing carboxyl or sulfonyl groups, and the like.

If the toner particles further comprise a radiation-curable (photopolymerizable) monomer, oligomer or polymer, the substrate can include an initiator for radiation curing.

Within the scope of the present invention, the substrate can further comprise a radiation-curable compound and / or a photoinitiator as described above. A substrate can include the radiation-emitting compound, and the toner particles can include an initiator for radiation curing as described above.

As described above, the curing reaction (reaction between the reactive groups RGA and RGB) of the present invention proceeds easily when the interpenetration between the toner particles and the substrate is very high. For this interpenetration, the toner particles are applied on the substrate (during fusing or in an additional heating step after fusing), preferably up to 15
Reached when heated to a temperature of 0 ^° , most preferably up to 120 ° C. Thus, it is beneficial for the toner receiving layer to have some fluidity at these temperatures. Thus, the toner receiving layer on the substrate contains waxes, or "heat solvents", also called "thermal solvents" or "thermosolvents", to promote the penetration of the reagents RGA and RGB, thereby increasing the kinetics of the curing reaction at elevated temperatures. Can be improved.

The term "heat solvent" in the present invention is in a solid state at a temperature lower than 50 ° C., but when heated above that temperature, it becomes a plasticizer for the binder of the layer into which it is inserted. Organic materials that cannot be hydrolyzed. Useful for that purpose is US-P 3,3
Polyethylene glycol having an average molecular weight in the range of 1,500 to 20,000 described in 47,675. Further, compounds such as urea, methylsulfonamide and ethylene carbonate described in U.S. Pat. No. 3,667,959 can be mentioned as a heat solvent, and tetrahydro-thiophene-1,1-dioxide,
Compounds such as methyl anisate and 1,10-decanediol are used in Research Disclosure, De.
member 1976, (item 15027) pa
ges 26-28, described as a heat solvent. Another example of heat solvent is US
-P3,438,776 and 4,740,446 and in published EP-A 0 119 615 and 0 12
2 512, as well as DE-A 3 339 810.

The toner receiving layer comprises a stabilizer, a toning agent, an antistatic agent, spacing particles (polymeric or inorganic) separately from the compound containing a reactive group RGB or a mixture thereof, and a binder or a mixture of binders. ) Can be included.

In addition to the components, the toner receiving layer may contain other additives such as free fatty acids, antistatic agents such as F ₃ C
(CF ₂ ) ₆ CONH (CH ₂ CH ₂ O) -H, a non-ionic antistatic agent containing a fluorocarbon group, an ultraviolet light absorbing compound, a white light reflective and / or ultraviolet reflective pigment And / or an optical brightener.

This first embodiment of the present invention comprises: i) toner particles containing reactive groups RGA
Means for image-wise application on a substrate comprising B, ii) fusing said toner particles to said substrate;
An apparatus for forming an image including the cured toner particles, including means for forming a cured toner image, is also included.

The first embodiment of the present invention further comprises: i) applying the toner particles comprising the reactive groups RGA, a UV-curable compound and a photoinitiator onto the substrate comprising the reactive groups RGB image-wise. Ii) fusing the toner particles to the substrate and fusing;
Means for forming a cured toner image; iii) an apparatus for the formation of an image containing the cured toner particles, comprising means for UV curing the UV curable compound. The means for UV-curing is UV-
Lamps are preferred. In the case of the device of the present invention, radiation (UV
-) The curing preferably proceeds online. Thus, the means for fusing the toner image emits infrared light (which is an infrared radiator) and the means for UV curing (e.g., one or more UV-emitting lamps, e.g., a high pressure mercury lamp). It is preferred that UV curing proceeds for a toner image that is placed immediately after the fusing means and is still fusing. Infrared radiator (means for melting toner particles) and UV emission lamp (means for radiation curing) in one station (fixing / curing station) so that melting and radiation curing proceed simultaneously Are also desirable design features of the device of the present invention. The apparatus of the present invention can include more than one fusing / curing station if so desired. The UV light emitting means is preferably a UV radiator having a capacity (intensity) of 20 W / cm to 150 W / cm.

If the toner particles further comprise a UV-curable compound, the means for fusing the toner image emits infrared radiation and the means for UV curing (eg, one or more UV-emitting lamps). ) Is placed immediately after the fusing means and UV curing is preferably performed on the still molten toner image.

[0061]

Second Embodiment of the Invention In a second embodiment of the present invention, the reactive groups RGB are applied on the toner image.

In the second embodiment of the present invention, the same toner particles as used in the first embodiment of the present invention and described above can be used.

The substrate used in the second embodiment is:
It can be any substrate known in the art, for example, a plastic film, paper, paperboard, etc. It can also be a substrate comprising a reactive group RGB as described above under the first embodiment of the invention.

The reactive compound applied over the image-wise deposited toner particles is a compound containing a reactive group RGB capable of reacting with the toner particles. Compounds carrying a reactive group RGB is 1 to 10 g / m ² in the image, are preferably applied in an amount of 2 to 8 g / m ^2.

Typical pairs of compounds which contain the reactive groups RGA and RGB and are very useful in the present invention are the same as those exemplified above.

For this second embodiment of the invention, it is also preferred that the toner particles have a Tg of ≧ 35 ° C. and comprise a resin containing a reactive group RGA. In a second embodiment of the invention, the compound bearing the reactive groups RGB can be applied to the toner image before or after fusing the toner particles to the substrate. If a compound containing a reactive group RGB is applied to the toner image before fusing, it is preferred to use a spray coating method for applying the compound. These compounds can be applied as such, as a solution, or as a dispersion, depending on the physical properties of the compound bearing the reactive group RGB.

In the second embodiment of the present invention, the non-
The toner image can be covered by a layer of transparent toner particles that are applied image-wise, wherein the transparent toner particles comprise a reactive group RGB and the compound bearing the reactive group RGB has a temperature of ≧ 35 ° C. It has a Tg. As used herein, the term "transparent" means not providing a visible diffused concentration in a wavelength range extending from 400 to 700 nm, wherein the visible diffused concentration is less than 15% of light integrated over that wavelength range. Is defined as the decrease of In this case, the toner particles are applied on the toner image before fusing.

The toner image does not contain any reactive groups RGB that can react with the reactive groups RGA contained in the image forming toner particles, but can also be covered with a layer of transparent toner particles that contain reactive groups RGA. . This layer of transparent toner particles is then covered with a compound containing the reactive groups RGB. Later, the two reactive groups are reacted together to cure the outermost toner layer in the toner image. Reliefs formed by overlaying several layers of toner particles of various types (for example, in the case of full-color toner images or black-and-white (monochrome) images having a wide tonal range as disclosed in EP-A 768 577) If a layer of transparent toner particles is applied to the toner image in which the structure is present, the layer of transparent toner particles is applied in a reverse image-wise manner, with a thicker fixed clear finish layer present in the thinner areas of the image, Thicker areas can have a thinner fixed clear finish layer present.

The present invention provides: i) image formation of toner particles containing a reactive group RGA on a substrate;
Ii) means for fusing the toner particles to the substrate to form a fused toner image, and further comprising combining a compound containing a reactive group RGB in the image-wise manner. An apparatus for forming an image containing the cured toner particles, characterized in that it includes means for applying on the applied toner particles, is also included.

The means for applying the compound bearing a reactive group RGB can be a roller, wick, spray or the like. If the means for applying a compound bearing a reactive group RGB is a roller, it can be a split roller, for example a 5 g / m ² compound bearing a reactive group RGB is applied. If it must be done, four application rollers can be provided, the first two applying together 2 g / m ² of the compound carrying the reactive groups RGB, and the subsequent rollers applying the remaining 3 g / m ^2. Apply A preferred means for the application of said compounds bearing the reactive groups RGB is Ther
proceedings of IS &T's El
event International Cong
lesson Advances in Non-Im
pact PrintingTechnology
s, page 219-222. Buche
r et al. "Innovative Re
lease AgentDelivery System
ms ”as described under the title“ ms ”
Felt (NOMEX is Du Pont de Nem
OURS, a brand name of Wilmington, US). This meeting is H
29.10.95-0 in the ilton Head
Opened at 3.11.95. Proceedings is IS
& T, Springfield, US 1995. Compounds bearing the reactive groups RGB can be delivered directly to the image by the feed roller described above, or on an intermediate roller that distributes the compound on average over the image.

The means for applying a compound containing a reactive group RGB onto the toner image may be prior to the means for fusing the toner particles or for fusing the toner particles to the substrate. Can be placed after said means for

If the means for applying the compound containing reactive groups RGB is installed after the fusing means, the reactive groups RGB are fused and applied over the still warm toner image, and the apparatus is preferably Also includes special means for reacting the reactive groups RGA and RGB to cure the fused toner image. These special means are heating means, which can be the same means used as the fusing means.

When the means for applying the compound containing a reactive group RGB is installed before the means for fusing the toner particles, the means for applying the compound having the reactive group RGB is used. These means are preferably means for non-contact application, such as spraying means, special means for reacting the reactive groups RGA and RGB to cure the fused toner image. Is not necessary because the reaction of the reactive groups RGA and RGB proceeds during the fusing step.

In the case of this second embodiment of the invention, too, it is possible to use toner particles and / or substrates which further comprise the radiation-curable, preferably UV-curable compounds described above. Thus, a second embodiment of the present invention provides: i) providing a substrate comprising the reactive groups RGB, i) imaging toner particles comprising the reactive groups RGA, a UV curable compound and a photoinitiator on the substrate. Ii) fusing the toner particles to the substrate to form a fused toner image; iii) applying a compound comprising a reactive group RGB to the image-wise applied toner particles. Iv) reacting said reactive group RGA with said reactive group RGB, and v) UV curing said UV curable compound. A method for forming a toner image on a substrate comprising: Including.

In this way, the UV curing step can be performed on-line, for example at the fusing station itself of the electrostatographic apparatus or at a station immediately adjacent to the fusing station.

The radiation curing can be performed off-line in another apparatus, in which case the fused toner particle layer is heated again and irradiated with a curing line.

I) a means for image-wise applying toner particles comprising a reactive group RGA, a UV-curable compound and a photoinitiator onto a substrate, ii) fusing the toner particles to the substrate Means for forming a fused toner image, which further comprises applying a compound comprising a reactive group RGB onto the image-wise applied toner particles, and the UV-curable An apparatus for forming an image containing the cured toner particles, characterized in that it includes means for UV curing the compound, is also within the scope of the invention.

In such an apparatus, the means for fusing and the means for UV curing can be the same as those described above under the first embodiment of the invention.

The present invention can be practiced in any electrographic or magnetographic imaging method. It can be useful in classical electrophotography, ionography, direct electrostatic printing (DEP), and the like. The invention is useful for monochrome toner images, as well as multi-color and full-color toner images. Thus, in an apparatus within the scope of the present invention, the means for image-wise depositing toner particles can be direct electrostatic printing means, wherein the charged toner particles are attracted to the substrate by an electric field and the toner stream is , Modulated by the printhead structure including the print aperture and the control electrodes. The means for image-wise depositing toner particles can also be a toner deposition means on which a latent image is initially formed. For such an apparatus within the scope of the present invention, said means for image-wise depositing toner particles include: means for forming a latent image on the latent image bearing component; deposition of said toner particles. Means for developing the latent image to form a developed image, and means for transferring the developed image onto the substrate.

The latent image can be a magnetic latent image (magnetography) developed with magnetic toner particles or, preferably, an electrostatic latent image. Such an electrostatic latent image is preferably an electrophotographic latent image, and the means for producing the latent image in the present invention is a light emitting means, such as a light emitting diode or a laser, wherein the latent image bearing component is a photoconductor. It is preferred to include

The toner particles useful in both embodiments of the present invention can have a volume average diameter of 1 to 50 μm, preferably 3 to 20 μm. If the toner particles are intended for use in color imaging, the volume average diameter should be between 3 and
10 μm is preferred, and 3-8 μm is most preferred. The particle size distribution of the toner particles can be of any type. However, essentially (preferably positive distortion with less particles less than the undistorted distribution, although some negative or positive distortion is allowed), the number or volume,
It is preferred to have a Gaussian or normal particle size distribution with a coefficient of variation (standard deviation divided by the average) (v) of less than 5, more preferably 0.3.

[0082] Toner particles useful in the first embodiment of the present invention may comprise any conventional toner component, for example, a charge control agent,
Both colored and black pigments, inorganic fillers and the like can be included. A description of charge control agents, pigments and other additives useful in the toner particles to be used in the toner compositions of the present invention can be found, for example, in EP-A 601 235.

The toner particles can be used as single-component developers, both magnetic and non-magnetic single-component developers. The toner particles can be used in a multi-component developer where both magnetic carrier particles and toner particles are present. Toner particles can be negatively charged and can be positively charged.

[0084]

【Example】

Example 1 Toner particles 49 parts of fumaric acid and DIANOL 33 polyester (No. 2 in Table 1) and 49 parts of terephthalic acid, isophthalic acid and 2 parts of DIANOL 22 and eletin glycol polyester (No. 3 in Table 1) With a Cu-phthalocyanine pigment (color index PB 15: 3) at 110 ° C. for 30 minutes in a laboratory kneader.

After cooling, the solidified mass was pulverized and
NE Fliessbettgegenstrahlm
Uhle 100AFG type (trade name), milled using ALPINE multi-plex jig-
It was further separated using a Zag sorter 100MZR (trade name). The average particle size of the separated toner
It was measured with a r Counter model Multisizer (trade name) and found to be 8.0 μm by volume.

Developer 4 parts of toner particles, 0.5 part of hydrophobic colloidal silica particles (BET value 130 m ² / g) were mixed with 95.5 parts of silicon-coated Cu having an average diameter of 55 μm.
-Mixed with Zn ferrite carrier particles.

On a portion of the glossy side of the substrate ZANDER PAPER®, 25.9 g in 71.5 g methyl ethyl ketone
Melamine-formaldehyde (cymel 303, A
American Cyanamid Company
(USA product name)

[0088]

Embedded image

A solution of 2.6 g of p-toluenesulfonic acid (catalyst) was coated with a bar coater to a wet thickness of 20 μm. After drying at 50 ° C. for 30 minutes, the dried layer had a thickness of 6 μm. There was no toner-receiving layer in the adjacent portion of the paper on the glossy side.

Printing Printing was performed on an AGFA XC305 color copier. The image was printed on both the portion of the paper with and without the receiving layer. After fixing of the image, the resistance of the image to the solvent was examined by rubbing the image ten times with a cloth soaked in MEK (methyl ethyl ketone).
The image of the part containing the receiving layer of the present invention resisted rubbing 10 times, but the image of the part without the receiving layer disappeared after rubbing once.

Embodiment 2 1. Preparation of Toner Particles and Developer Yellow toner (Y) 49 parts polyester having an acid value AV of 17 mg KOH / g (No. 2 in Table 1) and 49 parts polyester having an AV of 18 mg KOH / g (No. 3 in Table 1) ) To two parts of S
It was melt-blended with ICOECHTGELB D 1355 DD (color index PY13, trade name of BASF AG, Germany) at 110 ° C for 30 minutes in a laboratory kneader.

After cooling, the solidified mass was pulverized and
NE Fliessbettgegenstrahlm
Uhle 100AFG model (trade name), and milled using ALPINE composite jig-sag sorting machine 100MZ
It was further separated using an R type (trade name). The average particle size of the separated toner was measured with a Coulter Counter model Multisizer (trade name) and found to be 8.0 μm by volume.

In order to improve the fluidity of the toner mass, the toner particles are made up of 0.5% hydrophobic colloidal silica particles (BE).
(T-value 130 m ² / g).

Magenta toner (M) The production of yellow toner was repeated, but two parts of SICO
ECHTGELB 2 parts PERM instead of PY13
ANENT CARMIN FFB 02 (color index PR146, Hoechst AG, Germany
Trade name).

Cyan Toner (C) The production of the yellow toner was repeated.
ECHTGELB 2 parts HELI instead of PY13
OGEN BLAU D7070DD (color index P
B15: 3, trade name of BASF AG, Germany) was used.

Black toner (K) The production of the yellow toner was repeated.
2 parts CABO instead of ECHTGELB PY13
T REGAL 400 (carbon black, Cabo
t Corp. High Street 125, Bo
ston, U.S.A. S. A. Trade name).

The four toners, Y, M, C and K, are 120
At 500C had a melt viscosity of 500 Pas.

100 parts of a transparent toner (CT) epoxy resin EPICOTE 1004 (S
(Hell Chemical Co.) was melt compounded in a laboratory kneader at 110 ° C. for 30 minutes.

After cooling, the solidified mass was pulverized and
NE Fliessbettgegenstrahlm
Uhle 100AFG model (trade name), and milled using ALPINE composite jig-sag sorting machine 100MZ
It was further separated using an R type (trade name). The average particle size of the separated toner was measured with a Coulter Counter model Multisizer (trade name) and found to be 8.0 μm by volume. The transparent toner CT had a melt viscosity of 150 Pas at 120 ° C.

In order to improve the flowability of the toner mass, the toner particles are made up of 0.5% hydrophobic colloidal silica particles (BE).
(T-value 130 m ² / g).

Developing Agent Using each of the toners prepared above, the mixture of toner particles and colloidal silica was added at a ratio of 4% to 55 μm.
Silicon-coated Cu-Z having an average diameter of m
A carrier-toner developer was formed by mixing with the n-ferrite carrier particles.

2. Printing Examples Commercially available CHROMAPRESS (Agfa-Gevae
rt NV, Mortsel, and Belgium) to form a full-color toner image. The image was covered with a layer of clear toner such that 0.9 mg / cm ² of clear toner was present.

The fusion was performed at 120 ° C. using radiant heating. On the transparent toner layer, 370-410mgK
20 g of polyaminoamide resin (UNIREZ 1307 trade name) having an amino number of OH / g and 1.6 g
Catalyst (XB 3130, Ciba-Geigy, Sw
solution (trade name of Itserland) was applied to a wet thickness of 4 μm (ie 4 g of polyaminoamide resin per m ² ). Images were kept at 125 ° C. for 1 minute.

After the images were cooled, the images were rubbed ten times with a cloth soaked in MEK (methyl ethyl ketone) to examine the resistance of the images to the solvent. The image of the part treated with the hardener of the invention withstood 10 rubs, whereas the image of the part of the untreated layer disappeared after one rub.

The main features and aspects of the present invention are as follows.

1. i) the support and at least one on it
Providing a substrate having a toner receiving layer containing two reactive groups RGB; ii) providing toner particles containing at least one reactive group RGA; iii) image-wise disposing the toner particles on the substrate. Depositing to form an image; iv) a method for forming a toner image on a substrate comprising reacting the reactive group RGA with a reactive group RGB to cure the toner particles.

2. The reactive group RGA and the reactive group RG
B is contained in a compound forming a reactive pair, wherein the pair comprises: a polyaminoamide resin having an amine value of -140 to 430 mg KOH / g and a compound containing an epoxy group, having an acid value of more than 2.5 mg KOH / g A polymer and a compound having an epoxy group, a polymer having a hydroxyl value of more than 2.5 mg KOH / g and a compound having an epoxy group, a polymer having an epoxy group and polyaziridines, an acid having a hydroxyl value of more than 2.5 mg KOH / g -Polyaziridines and polymers having a hydroxyl value, -Polyaziridines and polymers having a hydroxyl value greater than 2.5 mg KOH / g, -Polyabietic acid and polymers having an acid value greater than 2.5 mgKOH / g, -2.5 mgKOH / g Polymer and polyavier with hydroxyl number greater than g A polymer having an acid number greater than 2.5 mg KOH / g and a highly methylated melamine resin; a polymer having a hydroxyl number greater than 2.5 mg KOH / g and a highly methylated melamine resin; The method of claim 1, wherein the method is a member selected from the group consisting of a polyamide resin, a curing agent containing an epoxy group, and a polyester / polyamide copolymer and a curing agent containing an epoxy group.

3. i) at least one reactive group RGA
Ii) depositing said toner particles image-wise on a substrate; iii) applying a compound comprising at least one reactive group RGB on said image; and iv) said reactive group. A method for forming a toner image comprising reacting RGA with the reactive groups RGB to cure the toner particles.

4. i) at least one reactive group RGA
Means for image-wise applying toner particles onto a substrate comprising: ii) means for fusing the toner particles to the substrate to form a fused toner image, which further comprises at least one Apparatus for forming an image comprising cured toner particles, comprising means for applying a compound having a reactive group RGB onto the image-wise applied toner particles.

Continued on the front page (72) Inventor Sergiu Tavernier Belgium B 2640 Malt Cell Septes Trat 27 Agfa-Gevuert Na Mrose Fennoutjaps (72) Inventor Danny Van Unsel Belgium B 2640 Malt Cell Septes Trat 27, Agfa-Gevert Naar, in Mrose-Fennoutjap

Claims (3)

[Claims] 1. i) providing a substrate having a support and a toner receiving layer thereon containing at least one reactive group RGB; ii) providing toner particles containing at least one reactive group RGA. Iii) image-wise depositing the toner particles on the substrate to form an image; and iv) reacting the reactive groups RGA with the reactive groups RGB to cure the toner particles. For forming a toner image on a sheet. 2. providing i) toner particles comprising at least one reactive group RGA; ii) image-wise depositing said toner particles on a substrate; iii) a compound comprising at least one reactive group RGB. Iv) on the image, and iv) reacting the reactive groups RGA with the reactive groups RGB to cure the toner particles to form a toner image. 3. A means for image-wise applying toner particles comprising at least one reactive group RGA onto a substrate; ii) fusing said toner particles to said substrate to form a fused toner image. Cured means comprising means for forming, further comprising means for applying a compound having at least one reactive group RGB onto the image-wise applied toner particles. An apparatus for forming an image containing toner particles.