JPH02192980A - Image forming device and image information - Google Patents

Abstract

PURPOSE:To ensure that various images are made to quickly responde with appropriate procedures and that thereby sharp images are formed, by providing a plate making device to form an insulating pattern on an electroconductive base and a device to supply a recording material with varying adhesive properties in accordance with the polarity of a voltage applied to an area between the patterned electroconductive base and an electroconductive member. CONSTITUTION:An insulating pattern 21 is formed on a base 1 using a plate making device 2. Next, ink 31 contained in an inking device 3 is applied to the surface of an electroconductive base 1 with the pattern 21 using coating rolls 32 to 37 of electroconductive basic material. At the same time, a voltage is applied to an area where the ink is present between the electroconductive base 1 and the coating roll 37 from a power supply 38. Then the adhesive properties of the ink 31 coming in contact with the electroconductive base 1 change, and the ink 31 is allowed to stick to the surface of the electroconductive base 1 in a pattern by the difference in the adhesive properties, and consequently, an ink image is formed. Next, the ink image 39 is transferred from the base 1 to a material to be recorded on 5 passing between the base 1 and an impression cylinder 4 while being pressed against the cylinder 4, thus forming the ink image on the material 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus for printing using ink whose adhesion changes with the application of voltage, and an image forming method using the apparatus.

[Prior Art 1 Conventional printing methods using ink include lithographic printing, letterpress printing, and gravure printing.

These methods involve complicated steps to create the plates, which make them too expensive, and require dampening water to butter the ink in the image and non-image areas on the plate. In addition, there were problems that needed improvement, such as the need for complicated operations to control the ink adhesion of the resin on the plate surface.

Therefore, an ink whose adhesion properties change depending on the applied voltage was proposed (see Japanese Patent Laid-Open Publication No. 71359/1983).
. An image forming method in which a voltage is applied to such ink in a desired pattern and adhesion and transfer is performed according to the pattern is relatively easy to make a plate, and the printing process is also relatively simple. Furthermore, since the amount of ink transferred can be controlled by the amount of electrical charge, there is no need to adjust the amount of ink using a large number of rollers as in conventional printing machines.

In the apparatus used in this image forming method, the voltage application in the pattern has conventionally been performed using a current-carrying head. In other words, a pattern with changed adhesion was formed due to this energization.

[Problems to be Solved by the Invention] An object of the present invention is to provide the above-mentioned ink image forming apparatus and its apparatus, which are further superior in that they can quickly respond to various images and that they can provide images of good quality. An object of the present invention is to provide an image forming method using the present invention.

[Means for Solving the Problems] The image forming apparatus of the present invention includes (a) a conductive substrate and a conductive member disposed opposite to the conductive substrate; (b) an insulating pattern is formed on the conductive substrate. Plate making means (c) means for supplying a recording material whose adhesion changes depending on the polarity of the applied voltage between the conductive substrate on which the pattern is formed and the conductive member (d) the conductive substrate and the conductive material It is characterized by having means for applying a voltage between the member and the member.

Further, the image forming method of the present invention includes (a) a plate-making step of manufacturing a plate by forming an insulating pattern on a conductive substrate; and (b) a conductive member disposed opposite to the conductive substrate and the conductive substrate. A recording material whose adhesion changes depending on the polarity of the applied voltage is supplied between the conductive substrate and the conductive member, and a voltage is applied between the conductive substrate and the conductive member to record any material on the conductive substrate or the conductive member. a step of (predominantly) attaching the recording material in a pattern to one side to form a recording material image; (c) a step of transferring the recording material image formed on the conductive substrate or conductive member to a recording medium It is characterized by having.

In the apparatus of the present invention, a plate having an insulating pattern formed on a conductive substrate is used. Therefore, compared to conventional devices in which a rod-shaped electrode is brought into direct contact with ink, this method is superior in that images of even better quality can be obtained.

Furthermore, since the apparatus of the present invention has a plate-making means, it can respond to a variety of images more quickly than a conventional apparatus that has this and performs image formation after setting a plate with a fixed pattern. It is excellent in many respects.

Hereinafter, one embodiment of the apparatus of the present invention will be described with reference to the drawings.

In FIG. 1, a conductive substrate 1 has a cylindrical shape and is a member that rotates in six directions of arrows. At least the surface of the conductive substrate is preferably formed of a conductor such as aluminum, copper, stainless steel, or platinum.

The plate-making means 2 is for forming an electrically insulating pattern 21 on a rotating conductive substrate, and includes, for example, a thermal transfer recording device that forms an insulating pattern with an insulating ink containing polymer, wax, etc. using a conventional thermal transfer method, or an electrophotographic method. Ordinary recording apparatuses can be used as they are, such as electrophotographic recording apparatuses that form toner images on insulators, and inkjet recording apparatuses that form patterns by jetting liquid insulating ink. Further, a polymerizable polymer precursor layer is formed on the conductive substrate 1, and a pattern image consisting of a polymerized portion and an unpolymerized portion is formed on the precursor layer by applying light and/or heat to the precursor layer. A polymerization image forming apparatus may be used that removes unpolymerized portions by etching or Beer-Apart method to form an insulating pattern consisting of polymerized portions. In addition, any material that can be coated with an electrically insulating material may be used, such as crayon, marker, paint, or other electrically insulating material.

In addition to the above, the plate making means 2 may be one in which a conductive pattern is formed by etching an insulating film formed on a base material by discharge breakdown, or a base coated with an insulating layer containing a silver compound may be used to form a conductive pattern. There are some that form conductive patterns by depositing.

An insulating pattern 21 is formed on the substrate l by the above-mentioned plate making means 2.
form. Next, the ink 31 in the ink applying means 3 is electrically applied to the coating rolls 32, 33, 3435, 36, 37 whose surfaces are made of a conductive material such as aluminum, copper, stainless steel, or platinum. It is applied onto a conductive substrate 1 provided with an insulating pattern 21. At the same time, the conductive substrate 1 with ink interposed
A voltage is applied between the coating roll 37 and the coating roll 37 by a power supply 38. Then, the ink 3 that comes into contact with the conductive substrate 1
The adhesion of ink 31 changes due to the difference in adhesion.
is deposited on the conductive substrate 1 in a pattern to form an ink image. Practically speaking, the voltage of the power supply 38 at this time is 3.
~100V, more preferably a DC voltage of 5-80V,
An AC bias voltage may be supplementarily applied.

In FIG. 1, the conductive substrate 1 side is the cathode and the coating roll 37 side is the anode, but depending on the properties of the ink used, the conductive substrate 1 may be the anode and the coating roll 37 side can be the cathode.

Further, the voltage from the power source 38 may be applied, for example, between the rotating shafts of the conductive substrate 1 and the coating roll 37, respectively.

The thickness of the layer of ink 31 formed on the surface of the ink coating roll 37 is (ink coating roll 37
This roll 37 is electrically conductive (although it varies depending on the size of the gap between the conductive substrate 1 and the conductive substrate 1, the fluidity or viscosity of the ink 31, the material or roughness of the surface of the ink coating roll 37, or the rotational speed of the roll 37). At the ink transfer position facing the sexual substrate 1, approximately 0.001 to 1
0mm, especially 0.005mm to 5mm, and even 0.01m
m to 2 mm is preferred.

If the layer thickness of this ink 31 is less than 0.001 mm, it will be difficult to form a uniform ink layer on the ink coating roll 37. On the other hand, this ink layer thickness is 10 mm
If it exceeds this, it becomes difficult to convey the ink 31 while keeping the surface layer of the ink layer (the layer in contact with the conductive substrate 1) at a uniform circumferential speed, and the ink coating roll 37
It also becomes difficult to conduct electricity between the conductive substrate 1 and the conductive substrate 1.

Next, the ink image 39 on the conductive substrate 1 is transferred to the conductive substrate 1.
The ink image is transferred onto a recording medium 5 (paper, cloth, metal sheet, etc.) that passes between the impression cylinders 4 rotating in the direction of arrow B while being in pressure contact with the ink image, thereby forming the ink image on the recording medium 5. In some cases, the ink image on the conductive substrate 1 may be transferred once to an intermediate transfer body such as a plan cylinder and then transferred again to a recording medium.

After the above-described image formation is repeated and the required number of sheets are completed, if unnecessary insulating patterns 21 and ink images remain, the remaining ink is scraped off from the conductive substrate l with the web of the cleaner 6. , new image formation can be performed. However, the cleaner 6 is in a non-contact state with the conductive substrate 1 during image formation, and is movable so as to be in contact with the conductive substrate 1 during cleaning. Cleaning methods include scraping with a blade, conveying a heated removal material such as paper to melt and remove the insulating pattern forming material, and removing with a web impregnated with a solvent.

Although the apparatus of the present invention preferably has the rete 6 (means for removing the pattern on the substrate 1) as described above, the present invention is not limited thereto, and the cleaning may be performed manually by an operator. Further, if a pattern is formed by wrapping a flexible conductive sheet or the like around the conductive substrate 1, it becomes possible to remove the pattern by discarding the sheet.

Further, in the apparatus of the present invention, as described above, it is preferable that the roll that supplies ink and the roll that applies voltage are the same, but the invention is not limited thereto. For example, when using a type of ink that has adhesive properties when no voltage is applied, but loses its adhesive properties when a voltage is applied,
As shown in FIG. 3, ink is uniformly supplied onto the pattern of the base 1 using the intermediate roll 40 as a conductive member, and then a voltage is applied between the conductive base 1 and the intermediate roll 40 to form a pattern. It may also be a device that transfers ink onto the intermediate roll 40 in a manner similar to that of the intermediate roll 40 .

As explained above, the image forming method of the present invention uses an ink whose adhesion changes depending on the polarity of an applied voltage between a conductive substrate having a desired insulating pattern and a conductive member disposed facing the conductive substrate. This method takes advantage of the fact that the adhesion of ink changes by applying a voltage, for example, between the pair of conductive substrates 1 and the conductive member.

Accordingly, the image forming method of the present invention can be divided into the following two types depending on the properties of the ink used. That is, (I) a type in which the ink has adhesive properties when no voltage is applied, and the adhesive properties disappear when a voltage is applied;

In this case, ink adheres to the insulating portion of the plate, forming a desired recorded image.

(II) A type in which the ink has no adhesive properties when no voltage is applied, but becomes adhesive when a voltage is applied.

In this case, ink adheres to the conductive portion of the plate, forming a desired recorded image.

Ink used in the image forming method of the present invention will be described below.

As mentioned in Types (I) and (II) above, the composition of the materials constituting the ink is determined by whether the ink is made to have adhesive properties or not from the beginning. It can be easily controlled by adjusting the proportions and types of constituent materials.

Regarding the mechanism by which the ink changes from adhesive to non-adhesive and from non-adhesive to adhesive due to voltage application, the following three cases can be considered depending on the composition of the ink.

(1) In the case of ink whose adhesion changes due to Coulomb force generated by voltage application.

The basic composition of this ink consists of inorganic or organic fine particles and a liquid dispersion medium, and the difference in chargeability of the fine particles is utilized. In this case, if the ink is adjusted to have adhesive properties from the beginning and contains fine particles that are easily charged negatively, the ink on the negative electrode side will not adhere when voltage is applied, and the ink will be adjusted to have adhesive properties. If particles that are easily charged positively are contained in the ink, the ink will not adhere to the positive electrode side when a voltage is applied. In addition, if the ink is adjusted so that it does not have adhesive properties at first, and then contains fine particles that are easily charged negatively, the ink on the positive electrode side will adhere when voltage is applied, and the ink will not have adhesive properties. When the ink is adjusted to contain particles that are easily positively charged as fine particles, the ink will adhere to the cathode side when a voltage is applied.

(2) In the case of ink whose adhesion properties change due to electrolysis of the ink and generation of gas when energized by voltage application.

This ink is originally adjusted to have tackiness. When this ink is sandwiched between electrodes consisting of an anode and a cathode and a voltage is applied and current is applied, non-adhesion occurs to either the anode or the anode electrode. The reason for this selective non-adherence is that electrolysis occurs near the electrodes due to current flow.
It is thought that gases such as hydrogen gas and oxygen gas are generated, and the one of the positive and negative electrodes, which generates a larger amount of gas, becomes non-adhesive.

As described above, the ink used in this case is selectively non-adherent to either the positive or negative electrodes, and as a result, almost the entire thickness of the part of the ink layer to which the voltage is applied is coated with the ink. Move to roll 37 (
(hereinafter referred to as bulk movement).

As an example, gas generation due to electrolysis of an OH group-containing solvent by energization and gas generation resulting from electrolysis of water by energization are shown below.

At the cathode, 2ROH"+2e--"Hz t+2RO- (generates 1 mole of hydrogen gas) 2H"+2e--H" ↑ (generates 1 mole of hydrogen gas) in the case of water At the anode, 2ROH-2RCHO+2H" +2e, in the case of water 20H--H20-t-!402↑+2e (Oxygen mole generation) As shown in the above formula, the amount of gas generated is proportional to the amount of electrons (e-'), that is, the current value, and only the cathode (OH group outside the water) (containing solvent), or twice the amount of gas is generated at the cathode than at the anode.In other words, if there is a chain that generates more than a certain amount of gas, then at one pole (in the case of the above equation) The ink becomes non-adhesive (at the cathode).In order for the ink to electrolyze and generate gas, it is necessary to add a solvent such as water, alcohol, or glycol, or a solvent such as sodium chloride or potassium chloride to the ink. Contains a solvent in which an electrolyte is dissolved.The lower the electrical resistance of the ink, the better, and the volume resistance is preferably 10'Ω·cm or less.If the volume resistivity exceeds 10'Ω·cm, the amount of current flowing decreases. Alternatively, a high voltage is required to prevent a decrease in the amount of current flowing.

(3) In the case of an ink whose adhesion properties change due to a change in the crosslinked structure of the ink or a change in the dissociation state of the electrolyte due to an electrochemical reaction when energized by voltage application.

In this case, the ink may be initially non-adhesive or may be adjusted to be adhesive; when the ink is adjusted to be non-adhesive, at least a portion of the crosslinked structure of the ink is changed or destroyed by energization; Adhesive properties are imparted by changing from a gel-like state to a sol-like state. Alternatively, the dissociation state of the electrolyte changes to impart adhesion. If the ink is adjusted to be adhesive from the beginning, the adhesive ink becomes non-adherent by a mechanism completely opposite to that described above.

The mechanism of change in adhesion of the ink used in the image forming method of the present invention depends on the ink used, as described in (1) and (2) above.
This is thought to be due to one of (3), but the above (1)
), (2), and (3) may occur at two or more times. In addition, the transfer of ink to the insulated or non-insulated parts of the plate may result in bulk transfer due to the relationship between the adhesive force and cohesive force of the ink at each interface, or partial transfer in which a part of the surface layer of the ink is transferred. It happens.

First, the ink that adopts the above mechanisms (1) and (2) will be explained below.

The ink used in the present invention may be one that adheres or does not adhere when no voltage is applied, but from the point of view of obtaining a good image, almost all of the ink in the non-image area is attached to the conductive material ( coating roll, etc.) or conductive substrate (plate, etc.) (bulk transfer). Preferably, the ink has adhesive properties when no voltage is applied. In this case, if the ink is a liquid such as water or alcohol, its cohesive force is weak, and suitable adhesiveness may not be obtained. In the present invention, for example, when the ink is applied to a platinum-plated stainless steel plate vertically erected to a thickness of 2 mm,
It is preferable that the ink be substantially retained on the platinum-plated stainless steel plate. In addition, ink was sandwiched between two platinum-plated stainless steel plates to make the ink thickness 2 mm, and when the two platinum-plated stainless steel plates were separated from each other with no voltage applied, ink did not appear on either plate. It is preferable that they adhere to the same degree.

Inks that employ mechanisms (1) and (2) are basically composed of inorganic or organic fine particles and a liquid dispersion medium. The fine particles in the ink make it easier to cut the ink and improve the resolution of the image. Ink is an amorphous solid of a colloidal sol and is a non-Newtonian fluid in terms of fluidity.

When the change in ink adhesion is caused by Coulomb force, easily charged fine particles are used, and the fine particles are charged by being kneaded in a liquid dispersion medium (described later), for example, in a homogenizer, colloid mill, or ultrasonic disperser. charged particles are generated. Particles that are positively charged include metals (
(Au, Ag, Cu, etc.) particles, sulfide (zinc sulfide Z
nS, antimony sulfide 5b2Ss, potassium sulfide 2S, calcium sulfide CaS, germanium sulfide G
eS, cobalt sulfide CoS, tin sulfide SnS, iron sulfide FeS, copper sulfide Cu, S, manganese sulfide MnS,
molybdenum sulfide MO233, etc.) particles, silicic acid (orthosilicic acid H45te4, metasilicic acid H2S+03, mesotrisilicate HzSizO*, mesotrisilicate H4S1303)
, mesotetrasilicate HaSi40+□, etc.) particles, polyamide resin particles, polyamideimide resin particles, etc., and particles to which a negative charge is imparted include iron hydroxide particles, aluminum hydroxide particles, fluoride particles, etc. mica particles,
Polyethylene particles, montmorillonite particles, fluororesin, etc. can be used. Further, polymer particles containing various charge control agents used as toners for electrophotography can also be used.

The above-mentioned fine particles have an average particle diameter of 100 μm or less,
Preferably, particles with a diameter of 0.1 μm to 20 LLm, especially 10 μm or less, can be used, and such fine particles are present in the ink in an amount of 1 part by weight or more, preferably 3 parts by weight to 9 parts by weight, and more preferably 3 parts by weight to 9 parts by weight, based on 100 parts by weight of the ink. Preferably, it can be contained in an amount of 5 parts by weight to 60 parts by weight.

Liquid dispersion media used in the ink include water, methanol, ethanol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol (weight average molecular weight, about 100 to 1000), ethylene glycol monomethyl ether. , ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, methylcarpitol, ethylcarpitol, butylcarpitol, ethylcarpitol acetate, diethylcarpitol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether , glycerin, triethanolamine, formamide, dimethylformamide, dimethylsulfoxide, N-methyl-2-pyrrolidone, 1,3-dimethylimidazolidinone, N-methylacetamide, ethylene carbonate, acetamide, succinonitrile, dimethylsulfoxide, Sulfolane, furfuryl alcohol, N,N-dimethylformamide, 2-ethoxyethanol, hexamethylphosphoric triamide (hexamethylphosphoric triamide)
, 2-nitropropane, nitroethane, γ-butyrolactone, brobylene carbonate)', 1,2,6-hexandriol, dipropylene glycol, hexylene glycol, etc. alone or a mixture of two of them can be used. . The liquid dispersion medium is 4 parts per 100 parts by weight of ink.
It is preferably contained in an amount of 0 to 95 parts by weight, more preferably 60 to 85 parts by weight.

In a preferred embodiment of the present invention, in order to control the viscosity of the ink, 1 to 90 parts by weight, more preferably 1 to 50 parts by weight of the above-mentioned polymer soluble in the liquid dispersion medium is added to 100 parts by weight of the ink material. It can be contained in an amount of 1 to 20 parts by weight, particularly 1 to 20 parts by weight. Such polymers include plant-based polymers such as guar gum, locust bean gum, gum arabic, taragant, carrageenan, pectin, mannan, and starch; microbial polymers such as xanthan gum, dextrin, succinoglucan, and curdlan; gelatin, casein, etc. , animal polymers such as albumin and collagen; cellulose polymers such as methyl cellulose, ethyl cellulose, and hydroxyethyl cellulose; starch polymers such as soluble starch, carboxymethyl starch, and methyl starch; alginic acid polymers such as propylene glycol alginate and alginate; Semi-synthetic polymers such as their geosaccharide derivatives: vinyl polymers such as polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl methyl ether, carboxyvinyl polymer, sodium polyacrylate; other polyethylene glycol, ethylene oxide, propylene oxide block copolymers , alkyd resin, phenol resin, epoxy resin, amino alkyd resin, polyester resin, polyurethane resin, acrylic resin, polyamide resin, polyamideimide resin, polyesterimide resin, silicone resin, and other synthetic polymers are used singly or in combination of two or more. be able to. It is also possible to use greases such as silicone grease and liquid polymers such as bolybdenum.

If the change in ink adhesion is due to the generation of gas due to electrolysis, the liquid dispersion medium may be a solvent such as water, methanol, ethanol, glycerin, ethylene glycol, propylene glycol, or sodium chloride or potassium chloride. A solvent in which an electrolyte such as the following is dissolved is preferably used. The contents of the liquid dispersion medium and fine particles are the same as those described above. In particular, it is preferable to use water or a liquid containing water as the liquid dispersion medium because hydrogen gas is likely to be generated on the negative electrode side. When water and another liquid dispersion medium are mixed, the content of water is preferably 1 part by weight or more and 80 parts by weight or less, more preferably 5 parts by weight or more and 60 parts by weight or less, based on 100 parts by weight of the ink.

In the case of ink that generates gas through electrolysis, the fine particles contained in the ink include, in addition to those listed above, silica, carbon fluoride, titanium oxide, carbon black, and the like.

In a preferred example of the ink, taking into consideration the viscoelastic properties of the ink, the fine particles are preferably swellable fine particles that take in and hold the liquid dispersion medium in the particles and swell.

For example, fluorinated mica such as Na-montmorillonite, Ca-montmorillonite, 3-octahedral synthetic smectite, Na-hectolite, Li-hectolite, Na-teniolite, Na-tetrasilicic mica and Li-teniolite, synthetic mica, silica and so on. The above-mentioned fluorinated mica can be represented by the following general formula (1).

General formula (1) % formula %) In the formula, W is Na or Li, X and Y are M g 2
+Fe”, Ni”, Mn”, AI”, Fe”,
6-coordinate ion such as Li'', Z is AI'', Si'', G
e”, Fe”, B” or a combination thereof (AI”/S
represents a cation with a coordination number of 4, such as i''').

The average particle diameter of the swellable fine particles is preferably 75 μm or less, more preferably 0.8 to 15 μm, and preferably 8 μm or less in a dry state.

In addition, the amount of swelling fine particles is 15 to 100 parts by weight of the ink.
It is preferred to use 65 parts by weight, especially 20 to 50 parts by weight.

The ink of the present invention may contain colorants such as carbon black and other dyes and pigments that are generally used in the fields of printing and recording, if necessary. When the ink contains a coloring material, the content of the coloring material is preferably 0.1 to 40 parts by weight, more preferably 1 to 20 parts by weight, based on 100 parts by weight of the ink. Further, instead of or together with the coloring material, a coloring compound that develops color upon application of voltage may be contained. In addition, the ink may contain an electrolyte, thickener, thinner, surfactant, etc. that impart conductivity. Furthermore, it is also possible for the above-mentioned fine particles themselves to also function as a coloring material.

Next, the ink that adopts the above mechanism (3) will be explained.

As the above-mentioned ink, an ink containing a liquid dispersion medium and a crosslinked structure substance or a polymer electrolyte that holds the liquid dispersion medium can be used.

The term "crosslinked substance" here refers to a substance that can form a crosslinked structure by itself, or a substance that forms a crosslinked structure by adding other additives (for example, a crosslinking agent made of inorganic ions such as borate ions). A substance that makes it possible to

Furthermore, the term "crosslinked structure" refers to a three-dimensional structure having "crosslinked bonds."

In the above-mentioned ink, this "crosslinking bond" may be constituted by any one of an ionic bond, a hydrogen bond, and a van der Waals bond (or a combination of two or more of these bonds).

In the above-mentioned ink, the above-mentioned "crosslinked structure" is sufficient as long as it can obtain the desired liquid dispersion medium retention property. That is, this crosslinked structure may be, for example, a network, honeycomb, or spiral structure, and may not be a regular structure.

In the above ink, various inorganic or organic solvents that are liquid at room temperature can be used as the liquid dispersion medium, but they have relatively low volatility (e.g., equivalent to or lower than water). ) It is preferable to use a solvent.

When a hydrophilic dispersion medium such as water or a water-containing dispersion medium is used as the liquid dispersion medium, a hydrophilic (natural or synthetic) polymer or the like is preferably used as the crosslinked structure substance.

Examples of such hydrophilic polymers include guar gum,
Plant polymers such as locust bean gum, gum arabic, taragant, carrageenan, pectin, mannan, and starch; Microbial polymers such as xanthan gum, dextrin, succinoglucan, and curdlan; Animal polymers such as gelatin, casein, albumin, and collagen. Polymers: Cellulose polymers such as methyl cellulose, ethyl cellulose, and hydroxyethyl cellulose; starch polymers such as soluble starch, carboxymethyl starch, and methyl starch; alginic acid polymers such as propylene glycol alginate, and alginate; Semi-synthetic polymers such as saccharide derivatives; vinyl polymers such as polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl methyl ether, carboxyvinyl polymer, sodium polyacrylate; other polyethylene glycol, ethylene oxide, propylene oxide block copolymers, etc. Synthetic polymers and the like are preferably used alone or in combination of two or more as necessary.

It is preferable to use these hydrophilic polymers in 0.2 to 50 parts by weight, sometimes 0.5 to 30 parts by weight, per 100 parts by weight of the liquid dispersion medium.

Another type of ink that contains a polymer electrolyte is one that contains a polymer electrolyte that is a polymer having a dissociative group in its polymer chain. Examples of substances that dissociate into polymer ions when dissolved in water include natural polymers such as alginic acid and gelatin; and those synthesized by introducing dissociative groups into synthetic polymers such as polystyrene sulfonic acid and polyacrylic acid. be.

Among polymer electrolytes, amphoteric polymer electrolytes that can be dissociated either as an acid or as a base like proteins are preferable in order to obtain a wide range of changes in adhesion properties when energized.

On the other hand, when using a dispersion medium made of oil such as mineral oil or an organic solvent such as toluene as the liquid dispersion medium,
For example, metal soaps of stearic acid such as aluminum stearate, magnesium stearate, and zinc stearate; other metal soaps made of similar metal salts of fatty acids such as valmitic acid, myristic acid, and lauric acid; or hydroxypropyl cellulose derivatives; Dibenzylidene D
-Organic substances such as sorbitol, sucrose fatty acid ester, dextrin fatty acid ester, etc. (similar to the hydrophilic polymers mentioned above) are preferably used alone or in combination of two or more as necessary.

When using hydrophilic polymers or metal soaps as mentioned above, the retention of the liquid dispersion medium and the film-forming properties of the ink will vary to some extent depending on the amount of these compounds or the combination of these and the liquid dispersion medium. Change. Although it is somewhat difficult to unambiguously determine the amount or combination of these components, it is important to ensure that the ink consisting of a liquid dispersion medium and a crosslinked substance or polymer electrolyte does not have adhesive properties. For this purpose, it is preferable to reduce the amount of solvent in the ink, or increase the degree of crosslinking if a crosslinked structure substance is used. Conversely, in order to have adhesive properties, it is preferable to increase the amount of solvent in the ink, contrary to the above, or to lower the degree of crosslinking if a crosslinked structure substance is used.

The ink that takes the above-mentioned mechanism (3) has the above-mentioned liquid dispersion medium and a crosslinked structure substance or a polymer electrolyte as essential components, but also contains dyes and pigments or colored fine particles as necessary. A coloring compound that develops color when energized, or an electrolyte that imparts the desired conductivity to the ink and enables the ink to generate heat when energized, and if necessary, a fungicide or preservative. It may contain additives such as.

As the colorant, dyes and pigments generally used in the fields of printing and recording, such as carbon black, can be used without particular limitation.

Furthermore, inorganic compound particles such as colloidal silica, titanium oxide, tin oxide, etc. may be added for the purpose of improving the printing durability of images.

In order to obtain an ink made of the above-mentioned components, for example, a liquid dispersion medium such as water, a crosslinked structure substance made of a hydrophilic polymer, etc. (if necessary, a crosslinking agent, a coloring agent, an electrolyte, etc.) and/or Alternatively, the mixture may be uniformly mixed with a polymer electrolyte while heating to form a viscous solution or dispersion, and then cooled to gel.

In addition, when using colored particles such as toner particles as a coloring agent, it is better to add the colored particles after mixing the crosslinked structure material or/and polymer electrolyte and the liquid dispersion medium while heating to make them uniform. preferable. Further, in this case, it is particularly preferable to mix at around room temperature in order to prevent agglomeration of toner particles and the like.

In the thus obtained ink, at least a part of the crosslinked structure is changed or destroyed by the application of electricity, and the ink changes from a gel-like state to a (reversibly) sol-like state, and changes according to the conductive pattern. Adhesive properties are imparted. Alternatively, the dissociation state of the polymer electrolyte is changed by energization, and adhesion is imparted depending on the energization.

When electricity is applied to the ink that adopts the above-mentioned mechanism (3), the pH value near the electrode changes due to an electrochemical reaction. That is, the exchange of electrons with the electrode causes a change in the crosslinked structure of the ink or a change in the dissociation state of the electrolyte, resulting in a change in adhesion.

If we explain the change in the crosslinked structure due to energization using a crosslinked product of polyvinyl alcohol and borate ions as an example, it can be assumed that the following phenomenon occurs.

The boric acid ion, which is crosslinked by bonding with the ○H group of polyvinyl alcohol, changes its pH value to the acidic side by an anodic reaction near the anode of electricity or by adding an electron acceptor such as hydrochloric acid, and electrons are taken away. It is presumed that this is because the crosslinked structure (at least a part of it) was destroyed, the molecular weight decreased, the viscosity decreased, and the ink became adhesive.

The reaction at this time is estimated as follows, for example.

To explain this using amino acids as an example, the pH can be adjusted by a cathodic reaction near the cathode by applying electricity or by adding an electron pair donor.
changes to the alkaline side, and the -NH5'' ion of the amino acid becomes -NH2.Also, the pH value changes to the acidic side due to an anodic reaction near the anode due to electric current or addition of an electron acceptor, and the -NH5'' ion of the amino acid becomes -NH2. 000-ion is -C
It becomes 00H.

As mentioned above, it is thought that the crosslinked structure changes due to a change in the dissociation state of the amino acid, which changes the pH and causes a difference in adhesion, and the reaction at this time is estimated as follows, for example.

Ht C-01l C)+2 Change in the dissociation state of the polymer electrolyte due to electric current (1) Cathode reaction due to electric current (2) Anodic reaction due to electric current [Example] The present invention will be described below according to Examples.

Example 1 Preparation of ink> 200 g of glycerin and lithium duolite (LjM
g2Li (SiJ+o)Fa, average particle size 2.5μ)
40g in a homogenizer at 10,000 rpm.
After kneading at m for 30 minutes, 200 g of water was added and mixed in a roll mill to prepare a gray amorphous solid colloidal sol ink.

After applying the above ink to a thickness of approximately 2 mm on a 1 cm x 1 cm platinum-plated stainless steel plate, the platinum-plated stainless steel plate of the same size was placed on top of the ink, and then the two sheets were coated under no voltage. When the two platinum-plated stainless steel plates were separated by gradually widening the interval between the platinum-plated stainless steel plates, ink was found to have adhered to almost the entire area on both platinum-plated stainless steel plates.

Next, a voltage of +30V was applied to both platinum-plated stainless steel plates with a 2 mm thick ink layer sandwiched between them, one of which was used as a cathode (earth) and the other as an anode. When the two platinum-plated stainless steel plates were separated by gradually increasing the interval between the plated stainless steel plates, all the ink adhered to the anode side electrode.
There was no ink adhesion on the cathode side. Note that the volume resistivity of this ink was 1243 Ω·cm.

Image Formation> FIG. 2 is a diagram showing an apparatus of the present invention using an electrophotographic recording apparatus as an insulating pattern forming means.

The photoreceptor 7 is an amorphous silicon photoreceptor with a diameter of 110 mm (copying speed 270 mm/sec, bright potential +50
(dark potential +750V), the diameter of the sleeve of the developing device 15 is 32 mm, the magnetic flux density in the vertical direction of the sleeve surface is 1000 Gauss, and the thickness of the developer on the sleeve is 0.2 mm.
, the distance between the sleeve and the photoreceptor is 0.3 mm %The developing bias applied to the sleeve is DC component +200■ and AC
Component 3, 1.4 k¥pp superimposed at OkHz, was used.

Further, as a developer, the following components were prepared using the method shown below.

・Styrene monomer ・・・3200
Weight parts: Cyclized rubber (Alpex CR450.

(Manufactured by Hoechst Japan) 400 parts by weight
Bontron 281 (charge control agent manufactured by Orient Chemical Industry Co., Ltd.) 80 parts by weight
2-ethylhexyl methacrylate...760 parts by weight.
40 parts by weight of polyethylene glycol dimethacrylate/carbon black (STERING R.

(manufactured by Cabot, USA) 600 parts by weight
Paraffin wax 155°F - 160 parts by weight (manufactured by Hiki Seiro ■) (softening point 69°C) The above components were mixed with an attritor at a temperature of 80°C for 4 hours to form a monomer composition. Prepared. Obtained monomer composition 2
54 parts by weight, 20 parts by weight of amino-modified silica (100 parts by weight of Aerosil 200 treated with 5 parts by weight of aminopropyltriethoxysilane) and 0.5 parts by weight. IN hydrochloric acid 2
1200 ml of distilled water heated to 85°C containing 5 parts by weight
Part by weight of the aqueous medium was poured into a TK homomixer while stirring, and after the addition, the mixture was stirred at 10,000 rpm for 15 minutes to disperse and granulate.

After granulation, the liquid temperature was lowered to 60°C, and 4 parts by weight of 2.2'-azobis-(2,4-dimethylvaleronitrile) and 2 parts by weight of 2,2'-azobisisobutyronitrile were added as polymerization initiators. Added to aqueous medium and stirred for 30 minutes. Furthermore, the stirring was changed to paddle blade stirring, and the mixture was stirred at 60° C. for 10 hours to complete the polymerization.

The obtained aqueous medium containing the polymerized toner is cooled and dehydrated,
The amine-modified silica was dissolved and removed by washing with a sodium hydroxide solution, washed with water, dehydrated, dried, and classified to obtain a volume average particle size of 4.4 μm (measured with a Kohter counter using a 100 μm aperture). 10 parts by weight of the polymerized toner, 0.3 parts by weight of zinc stearate powder, 0.3 parts by weight of hydrophobic silica (Aerosil R972, manufactured by Nippon Aerosil Co., Ltd.), and an average particle size of 4
A developer was prepared by mixing 90 parts by weight of 0 μm insulating carrier particles (formed from 75 parts by weight of triiron tetroxide and 25 parts by weight of epoxy resin).

Further, the conductive base roll 1 is a stainless steel base material whose surface is coated with a conductive rubber made by mixing RTV silicone rubber and conductive power-bond, and has an inner diameter of 150 mm, an outer diameter of 180 mm, and a silicone rubber thickness of 0.5 mm. The contact pressure between the photoreceptor and the conductive rubber was 2 kg/cm.
The toner image is fixed on the plate base material using a Teflon heating roller 8 at a fixing temperature of 120°C and a pressure of 30 kg/cm.
The test was carried out under conditions of "m".

Next, the contact between the photosensitive drum 7 and the conductive substrate 1 is removed at the nip portion N, and platinum-plated stainless steel cylindrical rolls (surface roughness Is) with a diameter of 30 mm are used as the ink coating rolls 32 to 37. The above-described ink was placed between the conductive substrate 1 and the conductive member 37. Next, the conductive substrate 1 was rotated in the six directions of arrows at a peripheral speed of 5 mm/sec.

When we printed with no voltage applied from the DC power supply 38 of this printing machine, we could not obtain an image-like printed matter, but when we printed with a DC voltage of 30V applied from the DC power supply 38, The ink adhered only to the insulating pattern of the conductive substrate 1, and many prints with sharp images were obtained (at this time, the conductive substrate 1 was used as a cathode and the ink coating roll 37 was used as an anode).

In addition, after printing the required number of sheets, the toner image on the substrate 1 can be easily removed by the cleaner 6, which is a web (solvent permeation) that does not come into contact with the substrate 1 during printing and comes into contact with the substrate 1 when cleaning is required. Ta.

Example 2 Preparation of ink> - Colloidal hydrated silicate (swelling particles) (manufactured by Kunimine Kogyo ■, trade name: Sumecton).

average particle size of 1 micron or less)...250 parts by weight.
Carbon black (manufactured by Cabot, USA).

Product name Steering R) 60 parts by weight
Water: 140 parts by weight/Glycerin: 280
Parts by weight of water, glycerin, and carbon black were mixed in an attritor for 48 hours to prepare a mixed solution, and then this mixed solution and a colloidal hydrous silicate were mixed in a kneader to obtain an ink having the above composition.

After applying the above ink to a thickness of approximately 2 mm on a 1 cm x 1 cm platinum-plated stainless steel plate, the platinum-plated stainless steel plate of the same size was placed on top of the ink, and then the two sheets were coated under no voltage. After placing the platinum-plated stainless steel plates, the two platinum-plated stainless steel plates were separated by gradually increasing the distance between the two platinum-plated stainless steel plates under no voltage, and both platinum-plated stainless steel plates were separated. However, ink was adhered to almost the entire area of both platinum-plated plates.

Next, a voltage of +30μ was applied to both platinum-plated stainless steel plates with a 2 mm thick ink layer sandwiched between them, with one side serving as the cathode (earth) and the other as the anode. When the two platinum-plated stainless steel plates were separated by gradually increasing the distance between them, all the ink adhered to the anode side electrode.
There was no ink adhesion on the cathode side. Further, the volume resistivity of this ink was 1470 Ω·cm.

Image Formation> Image formation was performed using the above ink and the apparatus shown in FIG.

In the apparatus shown in FIG. 4, a conventional thermal transfer printer was used as the plate-making means 2. That is, as the thermal transfer recording medium 2b on a sheet, a base material on which an insulating heat-melting polymer mainly containing polyethylene oxide resin, vinyl acetate resin, and carbon black is applied is used, and this thermal transfer recording medium 2b is connected to a current-carrying head. In step 2a, heat was applied in a pattern to form an insulating pattern on the conductive substrate 1.

A platinum-plated copper roll (300 mm in diameter) was used as the conductive substrate 1, and a stainless steel roll with a diameter of 30 mm was used as the ink coating roll 37, which was a conductive member. In addition, the ink coating roll 37 serves as an anode and the conductive substrate 1 serves as a cathode, and the DC power supply 38
Printing was carried out by applying a voltage of V, rotating the conductive substrate 1 at a rotation speed of 10 mm/sec in the six directions of the arrows, and using plain paper as the transfer medium, and a sharp printed matter was obtained.

However, at this time, the ink adhered only to the insulating pattern on the conductive substrate 1.

Further, after printing was completed, the insulating pattern on the conductive substrate 1 could be easily removed with a web of the cleaner 6 impregnated with a solvent.

[Effects of the Invention] As explained above, since the present invention uses a recording material whose adhesion changes depending on the polarity of the applied voltage, any plate-making means that can form an insulating part or a conductive part in a pattern can be used. An object of the present invention is to obtain an image forming apparatus and an image forming method that can be used with anything and eliminate the need for complicated plate-making steps required for conventional printing.

Further, since the image forming apparatus of the present invention includes a plate making means and a printing means for continuously executing the plate making means and printing means, it is possible to quickly print various images. Furthermore, in the present invention, the adhesion of the recording material changes depending on the polarity of the applied voltage, and this is used to form an image, so it has excellent environmental stability and is very easy to handle. butter,
Since the recording material is held in accordance with the pattern on the plate having a pattern, it is possible to form a high-quality image with almost no distortion.

[Brief explanation of the drawing]

1, 2, 3, and 4 are schematic sectional views showing respective embodiments of the image forming apparatus according to the present invention. 1... Conductive substrate 2... Plate making means 3...
Ink applying means 4... Impression cylinder 5... Recording object
6...Cleaner 7...Photoconductor 8
...Heating roller 9...Charger 10...
・Optical system 11... Document table 12... Static eliminator 13... Erase lamp 14... Toner cleaner 15... Toner developer 21... Insulating pattern 31... Ink 32 to 36...・Coating roll 37... Conductive member (coating roll) 38...
・Power supply 39... Ink image 40...
Conductive member (intermediate roll) Figure 1 Figure 3

Claims (1)

[Claims] 1) (a) A conductive substrate and a conductive member disposed opposite to the conductive substrate (b) A plate-making means for forming an insulating pattern on the conductive substrate (c) A means for forming an insulating pattern on the conductive substrate Means for supplying a recording material whose adhesion changes depending on the polarity of the applied voltage between the formed conductive substrate and the conductive member (d) Applying a voltage between the conductive substrate and the conductive member An image forming apparatus characterized by having means for. 2) (a) A conductive substrate and a conductive member disposed opposite to the conductive substrate (b) Plate making means for forming an insulating pattern on the conductive substrate (c) A conductive substrate on which the pattern is formed and (d) means for supplying a recording material whose adhesion changes depending on the polarity of the applied voltage between the conductive member and the conductive member; An image forming apparatus comprising means for transferring a recording material adhered in a pattern on either the conductive substrate or the conductive member to a recording medium. 3) The recording material according to claim 1, wherein the recording material is a recording material that adheres to an insulating pattern portion formed on the conductive substrate by applying a voltage between the conductive substrate and the conductive member. Image forming device. 4) Claim 1, wherein the recording material is a recording material that adheres to a non-insulating pattern portion formed on the conductive substrate by applying a voltage between the conductive substrate and the conductive member. image forming device. 5) The image forming apparatus according to claim 1, further comprising a cleaner for removing the insulating pattern from the conductive substrate. 6) The image forming apparatus according to claim 1, wherein the plate making means is a thermal transfer recording device. 7) The image forming apparatus according to claim 1, wherein the plate making means is an electrophotographic recording device. 8) The image forming apparatus according to claim 1, wherein the plate making means is an inkjet recording device. 9) The image forming apparatus according to claim 1, wherein the plate making means is a polymerization image forming apparatus. 10) As a recording material, it has adhesive properties when no voltage is applied, and by applying a voltage between the conductive substrate and the conductive member, at least the adhesive property to the conductive substrate or the conductive member is reduced. The image forming apparatus according to claim 1, which is a recording material. 11) As a recording material, it has adhesive properties when no voltage is applied, and by applying a voltage between the conductive substrate and the conductive member, gas is released from the conductive substrate and/or the conductive member side. 11. The image forming apparatus according to claim 10, wherein the recording material is a recording material whose adhesion is reduced on the side where a relatively large amount of gas is generated. 12) (a) Plate making step of manufacturing a plate by forming an insulating pattern on a conductive substrate (b) Applying voltage between the conductive substrate and a conductive member placed opposite to the conductive substrate A recording material whose adhesion changes depending on the polarity of the conductive substrate is supplied, and a voltage is applied between the conductive substrate and the conductive member to attach the recording material to either the conductive substrate or the conductive member. An image forming method comprising the steps of: (c) transferring a recording material image formed on a conductive substrate or a conductive member to a recording medium; 13) (a) Plate making step of manufacturing a plate by forming an insulating pattern on a conductive substrate (b) Applying voltage between the conductive substrate and a conductive member placed opposite to the conductive substrate A recording material whose adhesion changes depending on the polarity is supplied, and a voltage is applied between the conductive substrate and the conductive member so that the recording material is predominantly applied to either the conductive substrate or the conductive member. An image forming method comprising: (c) a step of depositing a recording material in a pattern to form a recording material image; and (c) transferring a recording material image formed on a conductive substrate or a conductive member to a recording medium. 14) The image forming method according to claim 12 or 13, comprising the step of removing the insulating pattern from the conductive substrate. 15) As a recording material, it has adhesive properties when no voltage is applied, and by applying a voltage between the conductive substrate and the conductive member, at least the adhesive property to the conductive substrate or the conductive member is reduced. Claim 12 or 1 using a recording material
3. Image forming method. 16) As a recording material, it has adhesive properties when no voltage is applied, and by applying a voltage between the conductive substrate and the conductive member, gas can be released from the conductive substrate and/or the conductive member side. 16. The image forming method according to claim 15, wherein a recording material is used in which adhesiveness is reduced on the side where a relatively large amount of gas is generated. 17) Claim 12 or 17) wherein the recording material is a recording material that adheres to an insulating pattern portion formed on the conductive substrate by applying a voltage between the conductive substrate and the conductive member. 13 image forming methods. 18) The recording material is a recording material that adheres to a non-insulating pattern portion formed on the conductive substrate by applying a voltage between the conductive substrate and the conductive member. Or 13 image forming methods.