JPH11174715A - Image holding base body and its regenerating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an image holding base body on which a toner can be removed with a small amt. of an image removing liquid and which can be dried with small electric power by rendering the surface of the image holding base body hydrophilic where an image removing liquid containing water is to be held and an image is peeled and removed by contacting with an image peeling body while heating. SOLUTION: The image holding base body has a paper layer at least partly essentially comprising a cellulose fiber and has an image comprising a heat- fusible or thermoplastic image forming material formed on this paper layer. An image removing liquid containing water is held by the base body and the body is brought into contact with an image peeling body while heating to peel and remove the image. The surface of the image holding base body is made hydrophilic. Namely, the surface is rendered to have high affinity with water so that the surface of the image holding base body holds the water of the image removing liquid essentially comprising water coming/permeating through the toner layer and that the surface reduces the adhesion strength with the toner. It is effective to control the contact angle with water to <=60 deg. compared to >=90 deg. contact angle of a conventional paper with water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproduced image carrier from an image carrier having a toner image formed on a paper layer, and more particularly to an image carrier sheet which can be reproduced and reused, and a method of reproducing the same.

[0002]

2. Description of the Related Art (1) With the recent adoption of OA, a large amount of printer paper and copy paper has been used. As a result, the problem of deteriorating the global environment due to deforestation has been caused. Conventionally, the only solution to this problem has been to remove the ink or the like on the used paper, crush it, make it again, and recycle it into paper called used paper. However, recently, paper has been developed which can remove a character image on paper used once by cleaning and reuse it for copying or printing.
For example, as such a paper, as described in JP-A-4-67043, the surface of a sheet-like support,
In particular, there may be mentioned those in which only one side is subjected to a release treatment, and the support subjected to the release treatment is marked so as to be distinguished from plain paper. However, such copying paper has the following disadvantages. It is a special paper with a release treatment on the surface,
It does not become general copy paper or printing paper used in large quantities, and has drawbacks in its application. Therefore, there is a difficulty in copying by mixing with general copying paper. Furthermore, from the viewpoint of resource reuse, double-sided copying,
That is, front and back double-sided copying of one copy sheet is important, and will be the mainstream in the future. Under such circumstances, there is a difficulty in using recycled paper coated with a release agent on one side. An image is formed on the release agent, and, of course, has poor fixability and is difficult to use.

(2) JP-A-1-101576 and JP-A-1-101577: An image-formed support is immersed in an organic solvent for dissolving an image-forming toner resin on the image-formed support, and subjected to ultrasonic treatment. This removes the image from the support on which the image has been formed. However, these methods have problems such as pollution, ignitability, and toxicity due to the use of an organic solvent, and have problems in use in general offices and homes.

(3) JP-A-1-297294: An image formed on a plastic, metal, paper having poor liquid permeability, ceramic or the like is used as an image forming support. Is heated with a hot-melt release body in between to remove the image from the support, but a special paper (erasable paper) with a release treatment on the surface must be used. However, there is a drawback that it cannot be applied to general copying paper, printing paper, and the like that are currently used in large quantities.

(4) JP-A-7-13383, JP-A-7
No. 110644: General copying paper currently used in large quantities, in contrast to the above methods (1), (2) and (3).
As a method of taking a toner image copied on printing paper or the like, at least a portion is formed of a paper layer mainly composed of cellulose fiber, and a hydrophobic image made of a thermo-flexible ink (toner) is formed on the paper layer. An image in which a hydrophobic image is peeled from a paper layer by holding an image peeling liquid containing water on an image holding body that is in contact with the hydrophobic image and the image peeling body in the holding state of the image peeling liquid. A method for regenerating a holding support has been proposed. However, various problems remain to implement it concretely. For example, when an image release liquid is immersed in an image holding support (copying paper), 1 g or more per copy paper A4 size (normally 35 g / A
4) There is a problem that a large amount of power is consumed for drying or wrinkles easily occur because of consumption.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image holding support capable of peeling a toner with a smaller amount of an image stripping liquid and drying with a small amount of power, and a method for regenerating the image holding support. It is in.

[0007]

According to the present invention, firstly, at least a part is formed of a paper layer mainly composed of cellulose fiber, and a heat-fusible or thermoplastic image forming layer is formed on the paper layer. An image-removing support containing water is held on an image-holding support on which an image made of a substance is formed, and the image is peeled and removed by bringing the image-removing solution into contact with the image-releasing body by heating, and the surface thereof is hydrophilic. An image-bearing support characterized in that the image-bearing support is characterized in that: Secondly, the first image holding support is provided, wherein the surface of the image holding support has a contact angle with water of 60 degrees or less. Third, the first or second image holding support is provided, wherein the surface of the image holding support contains a hydrophilic resin. Fourth, the surface of the image holding support is
The first, second or third image holding support described above is characterized by containing polyvinyl alcohol. Fifth, the first, second or third image holding support is provided, wherein the surface of the image holding support contains polyvinyl alcohol and polyamide epichlorohydrin. Sixth, the image holding support according to any one of the first to fifth aspects, wherein the surface of the image holding support contains a surfactant. Seventh, there is provided the sixth image holding support described above, wherein the surfactant is a surfactant having a surface tension of a 1% aqueous solution of 30 mN / m or less.

[0008] Eighth, according to the present invention, at least a part of the image is composed of a paper layer mainly composed of cellulose fibers, and the paper layer is formed of a thermofusible or thermoplastic image forming substance. An aqueous solution containing a surfactant is used as an image stripping solution in the image-holding support on which is formed 0.1 to 1.
A method for regenerating an image-bearing support is provided, wherein the image-forming substance is peeled off from the image-bearing support by holding it at 0 g / A4 and bringing it into contact with an image peeling body by heating.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. Examples of the image holding support of the present invention include mainly copying or printing paper, but are not limited thereto, and may be any as long as they hold an image on the image holding support. Further, it is not necessary that the image-holding support is entirely composed of a paper layer, and the layer in which the hydrophobic image is held by the image-forming substance (toner) may be a paper-based layer containing cellulose fibers as a main component. For example, it may be a laminate of a paper layer and a plastic layer.

The image holding support of the present invention is characterized in that its surface is made hydrophilic. The required properties of the image-holding support, which is easier to peel off the toner, are as follows. The surface of the image-holding support retains water by an image peeling liquid containing water as a main component that has penetrated the toner surface, and the adhesive force with the toner is weakened. It is in. For this purpose, it is necessary to provide a water-repellent surface, rather than a water-repellent surface as in conventional paper. Specifically, it has been found that while the contact angle of conventional paper with water is 90 degrees or more, it is effective to set the contact angle to 60 degrees or less.

In order to make the surface of the image carrier hydrophilic, it is effective to add a hydrophilic resin such as polyvinyl alcohol, starch, carboxymethyl cellulose, polyethylene glycol and the like. In particular, polyvinyl alcohol and polyvinyl alcohol and polyamide The addition of epichlorohydrin was effective.

Further, ordinary paper treated with a surfactant as the surface of the image holding support also becomes a hydrophilic surface and is effective. In particular, the surfactant gives a low surface tension, specifically, the surface tension of a 1% aqueous solution is 30 mN.
/ M or less was effective.

In order to peel the toner from the toner image formed on the image holding support having a hydrophilic surface, an image peeling liquid (aqueous solution containing a surfactant) is applied to the toner image surface. In a state where the toner is supplied and held in the range of 0.1 to 1.0 g / A4, the toner is brought into contact with the image peeling body by heating to peel off the toner from the image holding support and transfer to the image peeling body. The supply and holding of the image release liquid to the toner image surface of the image holding support can be performed by impregnation such as immersion, dipping, or spraying. In the conventional method, in order to peel the toner with an image peeling liquid of 0.1 g / A4 or more and 1.0 g / A4 or less, the concentration of the surfactant must be 10% by weight or more, preferably 20% by weight. However, when the image carrier having a hydrophilic surface according to the present invention is used, the toner can be peeled at a surfactant concentration of 5% by weight or less, preferably 0.5 to 1.0% by weight.

The peeling of the toner can be performed by a peeling test apparatus using a relatively short heating contact (1 to 2 seconds) shown in FIG. 1 or a peeling test apparatus using a longer heating contact (2 to 20 seconds) shown in FIG. preferable. The image holding support from which the toner has been removed can repeatedly form an image with a copying machine or a printer.

As a material constituting the image peeling member, a polymer material, in particular, an organic polymer material having an SP value similar to a substance (toner) constituting an image, a metal material having a high surface active energy, and a vapor deposition material thereof And inorganic materials such as ceramic materials. Examples of the polymer material for forming the image-separated body include the above-mentioned water-soluble resin and toner component resin or the following component resin of an adhesive.
However, the type of resin may be any as long as it has adhesiveness to an image, and may be water-soluble or water-insoluble. (Component resin of adhesive) glue, gelatin, albumin,
Protein-based resins such as casein, starch-based resins, cellulose fiber-based, carbohydrate-based resins such as complex polysaccharides (such as gum arabic and tragacanth), vinyl acetate polymers and copolymers, acrylics, ethylene copolymers, Thermoplastic resins such as polyamide, polyester and polyurethane, and rubber resins such as polychloroprene, nitrile rubber, recycled rubber, SBR and natural rubber.

The resin forming the image peeling member can be used by being supported on another support, for example, a surface of a roller, a sheet, a belt or a tape. Examples of such a toner peeling means include a cellophane tape, a kraft paper tape, a polyvinyl chloride tape, an acetate tape, and an adhesive tape having a rubber-based or acrylic-based pressure-sensitive adhesive layer provided on a support of a filament tape. And the like. Further, a peeling means having a shape of a roller, a sheet, a belt, a tape or the like can be formed and used by the resin itself. Furthermore, the support is formed of a material whose surface is porous or has irregularities,
Alternatively, it is preferable that the surface of the support is processed to be uneven.
The term "peeling means" as used herein refers to an image holding device in which, when heated or pressurized, the image is brought into contact with the image-separated body having the property of adhering to the image, and the image is transferred to the image-separated body. Means for peeling off from the support.

The surfactants used in the present invention include a great variety of types, and generally, anionic (anionic) surfactants such as fatty acid derivative sulfate, sulfonic acid type and phosphate ester type, Examples include cationic (cationic) surfactants such as quaternary ammonium salts, heterocyclic amines, and amine derivatives, amphoteric surfactants, and nonionic surfactants, and any of these types of surfactants can be used. From the viewpoint that it is difficult to change the surface resistance of the recycled paper, it is desirable to use a nonionic surfactant. In addition, silicone-based surfactants, particularly silicone-based surfactants in which at least a part of a hydrophobic group is composed of methylsiloxane and at least a part of a hydrophilic group is a polyalkylene oxide and / or a carboxylic acid group, It is more preferable because it can improve reproduction deterioration due to the silicone oil adhered at the time of fixing, increase whiteness, and improve recopying and reprinting. The surfactant is used as a liquid containing water as described above, but may be contained in the image support itself before forming an image. In this case, water is used as an image stripping liquid. Can be.

The concentration of the surfactant in the image holding support is
Preferably it is 0.01 to 20% by weight, more preferably 0.01 to 5% by weight. If the concentration of the surfactant is too high, conductivity is imparted to the paper, which is not preferable for re-copying. On the other hand, the concentration of the water-soluble resin in the image-removing support capable of supporting the image peeling solution containing the water-soluble resin and the hydrophobic image is preferably 0.1 to 20% by weight, more preferably 0.5 to 20% by weight. 10% by weight. If the concentration of the water-soluble resin is too high, the viscosity increases, and the permeation into the paper is undesirably slow.

[0019]

Next, the present invention will be described in detail with reference to examples. Here, all parts and percentages are based on weight.

Example 1 65 g / m ² plain paper was coated with 2 g / m ² of polyvinyl alcohol (PVA117 manufactured by Kuraray Co., Ltd.) by dry weight and dried at 120 ° C. (at a coating speed of 200 m / min.). 1
0 seconds) Super calender (120 ° C, 220
kg / cm). The image holding support thus obtained had a water contact angle of 45 degrees. The image holding support is provided with a copying machine manufactured by Ricoh (Spirio 70).
00), 0.3 g / A4 of a 0.5% aqueous solution of a surfactant (manufactured by Mitsui Cytec Co., Ltd., aerosol OT) was applied using the peel test apparatus shown in FIG.
When the image was peeled at 0 ° C. and a peeling speed of 30 mm / s, the toner was almost completely peeled. The reproduced image holding support thus obtained was likewise manufactured by a Ricoh copier (Spi
rio 7000), and good reproduction image quality was obtained even when used repeatedly 5 times.

Example 2 On a 75 g / m ² plain paper, 3 parts by weight of 2 g / m ² polyvinyl alcohol (manufactured by Kuraray, PVA318) and polyamide epichloropidrin (manufactured by Nippon PMC, WS)
570) One part of the layer was coated, dried and then heat-treated at 100 ° C. for 8 hours. The image holding support thus obtained had a contact angle with water of 50 degrees. A copying machine manufactured by Ricoh Company (Spirio 7000)
, And 1% surfactant (Aerosol MA80, manufactured by Mitsui Cytec Co., Ltd.) using the peel tester shown in FIG.
0.8 g / A4 of the aqueous solution is adhered, and the peeling temperature is 100 ° C.
When the image was peeled at a peeling speed of 20 mm / s, the toner was almost completely peeled. The reproduced image holding support thus obtained was similarly used with a copying machine manufactured by Ricoh Company (Spirio 7).
000), and good reproduction image quality was obtained even when used repeatedly 5 times.

Example 3 FIG. 2 was placed on Ricoh PPC paper (type 6000).
1.0% aqueous solution of a surfactant (Aerosol OT, manufactured by Mitsui Cytec Co., Ltd.) using a stripper coating device of 1.0 g / A4
The paper obtained by adhering and drying has a water contact angle of 30.
Degree. Using this paper, a Ricoh copier (Spi
rio 6000) and make a 1.0 copy with the device of FIG.
% Surfactant (Aerosol OT, manufactured by Mitsui Cytec)
An aqueous solution of 0.2 g / A4 was adhered, and a peeling temperature of 120 ° C.
When the image was peeled at a peeling speed of 30 mm / s, the toner was almost completely peeled. The thus-obtained reproduced image holding support is similarly used with a Ricoh copier (Spirio 6).
000), and good reproduction image quality was obtained even when used repeatedly 5 times. In addition, 1% of this aerosol OT
The aqueous solution had a surface tension of 26 mN / m.

Example 4 FIG. 2 was placed on PPC paper (type 6000) manufactured by Ricoh Company.
1.0% aqueous solution of a 1% surfactant (Aerosol MA80, manufactured by Mitsui Cytec Co., Ltd.)
The paper obtained by applying A4 and drying had a contact angle to water of 20 degrees. Using this paper, a Ricoh copier (S
2 and a 0.8% aqueous solution of a 1.0% surfactant (Aerosol MA80, manufactured by Mitsui Cytec Co., Ltd.) was applied using the apparatus shown in FIG. Upon peeling, the toner was almost completely peeled. The reproduced image holding support thus obtained was similarly copied by a Ricoh copier (Sp
rio 6000), and good reproduction image quality was obtained even after repeated use five times. The 1% aqueous solution of the aerosol MA80 had a surface tension of 28 mN / m.

Comparative Example 1 The contact angle of water with Ricoh's PPC paper (type 6000) was 120 degrees. Using this PPC paper, as in Example 1, a Ricoh's copier (Spirio 700) was used.
0), 0.3 g / A4 of a 0.5% aqueous solution of a surfactant (aerosol OT, manufactured by Mitsui Cytec Co., Ltd.) was applied using the apparatus shown in FIG. 1, and a peeling temperature of 120 ° C. and a peeling speed of 30 mm / When the image was peeled at s, the toner was hardly peeled.

Comparative Example 2 FIG. 2 was placed on RPC PPC paper (type 6000).
1.0 g / A4 aqueous solution of 1% surfactant (Aerosol A196, manufactured by Mitsui Cytec Co., Ltd.)
The paper obtained by adhering and drying has a water contact angle of 70.
Degree. Using this paper, a Ricoh copier (Spi
rio6000), and copy it with the device of FIG.
% Surfactant (Aerosol OT, manufactured by Mitsui Cytec)
1.0 g / A4 of the aqueous solution was applied, and the peeling temperature was 120 ° C.
When the image was peeled at a peeling speed of 30 mm / s, the toner was hardly peeled. In addition, the surface tension of this 1% aerosol A196 aqueous solution was 35 mN / m.

Comparative Example 3 A copy was made on the image holding support used in Example 1 with a copying machine (Spirio 7000) manufactured by Ricoh Co., Ltd.
2.0% aqueous solution of a surfactant (Aerosol OT, manufactured by Mitsui Cytec Co., Ltd.) using a peel tester
When the toner was adhered and the image was peeled at a peeling temperature of 120 ° C. and a peeling speed of 30 mm / s, the toner was almost completely peeled. However, the reproduced image holding support thus obtained is likewise used with a Ricoh copier (Spirio 700).
When the copy was performed in step 0), wrinkles occurred, and it could not be used twice or more repeatedly.

Comparative Example 4 A Ricoh copier (Spiri) was used on plain paper of 75 g / m ^2.
o7000), 0.05 g / A4 of a 1% aqueous solution of a surfactant (Aerosol MA80, manufactured by Mitsui Cytec Co., Ltd.) was applied using the peel test apparatus shown in FIG. When the image was peeled in s, the toner was not completely peeled.

[0028]

According to the first aspect of the present invention, since the surface of the image-holding support is hydrophilic, the surface of the support is retained by the release liquid containing water as a main component, and the adhesive force with the toner is improved. Since the toner is weakened, an image holding support from which the toner can be easily separated is obtained. According to the second to seventh aspects of the present invention, since the adhesive force between the surface of the support and the toner is further reduced, it is possible to obtain an image holding support in which the toner can be more easily separated. According to the eighth aspect of the present invention, when the image holding support having the hydrophilic surface is used, the toner can be peeled at a surfactant concentration of 1% or less.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a peeling test apparatus employed in Examples and Comparative Examples.

FIG. 2 is a diagram illustrating a peeling test apparatus used in Examples and Comparative Examples.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Peeling belt (for toner peeling) 2 Image peeling liquid P Paper with toner image R ₁ Opposite roller R ₂ Application roller R ₃ Image peeling roller

Claims (8)

[Claims] 1. An image-bearing support comprising at least a part of a paper layer mainly composed of cellulose fibers and forming an image of a thermofusible or thermoplastic image-forming substance on the paper layer. Holding an image stripping solution containing water,
An image holding support, wherein the image is peeled and removed by bringing this into heat contact with an image peeling body, the surface of which is hydrophilic. 2. The image holding support according to claim 1, wherein the surface of the image holding support has a contact angle with water of 60 degrees or less. 3. The image holding support according to claim 1, wherein the surface of the image holding support contains a hydrophilic resin. 4. The image holding support according to claim 1, wherein the surface of the image holding support contains polyvinyl alcohol. 5. The image holding support according to claim 1, wherein the surface of the image holding support contains polyvinyl alcohol and polyamide epichlorohydrin. 6. The image holding support according to claim 1, wherein the surface of the image holding support contains a surfactant. 7. The image holding support according to claim 6, wherein the surfactant is a surfactant having a surface tension of a 1% aqueous solution of 30 mN / m or less. 8. An image-bearing support comprising at least a part of a paper layer mainly composed of cellulose fibers and forming an image formed of a thermofusible or thermoplastic image-forming substance on the paper layer. An aqueous solution containing a surfactant is held at 0.1 to 1.0 g / A4 as an image release liquid, and the image forming substance is released from the image holding support by heating and contacting the image release material. A method for regenerating an image holding support.