JP2021157105A - Belt for image forming apparatus and image forming apparatus - Google Patents

Abstract

To provide a belt for an image forming apparatus that can prevent image omission due to continuous use.SOLUTION: A belt for an image forming apparatus has a substrate, an elastic layer provided on the substrate, and self-repairing resin particles, when having a surface layer on the elastic layer, contains the self-repairing resin particles in the surface layer in a state in which the self-repairing resin particles are exposed from a surface of the surface layer, and when not having the surface layer on the elastic layer, contains the self-repairing resin particles in the elastic layer in a state in which the self-repairing resin particles are exposed from a surface of the elastic layer.SELECTED DRAWING: Figure 1

Description

The present invention relates to a belt for an image forming apparatus and an image forming apparatus.

Patent Document 1 states that "an intermediate transfer body to which a toner image obtained by developing a latent image formed on an image carrier with toner is transferred, and the intermediate transfer body has a base layer and a spherical shape from at least the inside. It consists successively comprising a laminated structure an elastic layer having an irregular shape with fine grains, the volume resistivity of the spherical particles and less than ^{1 × 10 0 Ω · cm 1} × 10 -4 Ω · cm or more intermediate Transcript. ”Has been proposed.

Patent Document 2 states that "an intermediate transfer body to which a toner image obtained by developing a latent image formed on an image carrier with toner is transferred, and the intermediate transfer body is a base layer and an elastic layer. wherein the but has been laminated, the elastic layer has an irregular shape with fine grains on the surface, the volume resistivity of the fine particles is ^{1 × 10 0 Ω · cm~1 ×} 10 6 Ω · cm An intermediate transcript. ”Has been proposed.

Patent Document 3 states that "an intermediate transfer belt on which a toner image obtained by developing a latent image formed on an image carrier with toner is transferred, and the intermediate transfer belt is a base layer and spherical fine particles. An intermediate transfer belt comprising, and having an elastic layer having an uneven shape due to the spherical fine particles, wherein the elastic layer contains a phosphorus compound, a metal hydrate, and a clay mineral. . ”Is proposed.

Japanese Unexamined Patent Publication No. 2019-128585 Japanese Unexamined Patent Publication No. 2018-155953 JP-A-2019-120742

An object of the present invention is that in an image forming apparatus belt having a base material, an elastic layer provided on the base material, and resin particles, the resin particles are melamine resin particles and the surface of the elastic layer. It is an object of the present invention to provide a belt for an image forming apparatus capable of suppressing image omission due to continuous use as compared with the case where the resin particles are contained in the elastic layer so that the resin particles are exposed.

The above problem is solved by the following means. That is, <1>
With the base material
An elastic layer provided on the base material and
With self-healing resin particles,
When the surface layer is provided on the elastic layer, the self-repairing resin particles are contained in the surface layer in a state where the self-repairing resin particles are exposed from the surface of the surface layer.
When the elastic layer does not have a surface layer, the image forming apparatus belt contains the self-repairing resin particles in the elastic layer in a state where the self-repairing resin particles are exposed from the surface of the elastic layer.
<2>
The belt for an image forming apparatus according to <1>, wherein the volume average particle diameter D50v of the self-healing resin particles is 5 μm or more and 20 μm or less.
<3>
The belt for an image forming apparatus according to <1> or <2>, wherein the self-healing resin particles are particles containing an acrylic urethane resin.
<4>
In the above <3>, the particles containing the acrylic urethane resin have a Martens hardness of 0.5 N / mm ² or more and 220 N / mm ² or less at 23 ° C. and a return rate of 70% or more and 100% or less at 23 ° C. The belt for the image forming apparatus described.
<5>
The acrylic urethane resin includes a hydroxyl group-containing acrylic resin (a), a polyol (b) having a plurality of hydroxyl groups and having the hydroxyl groups via a carbon chain having 6 or more carbon atoms, and a polyfunctional isocyanate (c). The image forming apparatus belt according to <3> or <4>, which is a reaction product of.
<6>
Any one of the above <1> to <5> in which the abundance ratio of the self-healing resin particles exposed from the surface of the surface layer or the elastic layer is 400 / mm ² or more and 40,000 / mm ^{2 or less.} The belt for an image forming apparatus according to.
<7>
The belt for an image forming apparatus according to any one of <1> to <6>, wherein the surface layer has a thickness of 1.0 μm or more and 20.0 μm or less.
<8>
The belt for an image forming apparatus according to any one of <1> to <7>, wherein the surface roughness Ra of the surface layer or the elastic layer is 0.1 μm or more and 10.0 μm or less.
<9>
The belt for an image forming apparatus according to any one of <1> to <8>, wherein the surface layer contains an acrylic urethane resin.
<10>
The acrylic urethane resin includes a hydroxyl group-containing acrylic resin (a), a polyol (b) having a plurality of hydroxyl groups and having the hydroxyl groups via a carbon chain having 6 or more carbon atoms, and a polyfunctional isocyanate (c). The belt for an image forming apparatus according to <9>, which is a reaction product of.
<11>
An image forming apparatus including the image forming apparatus belt according to any one of <1> to <10>.

According to the invention according to <1>, <3>, <9> or <10>, in an image forming apparatus belt having a base material, an elastic layer provided on the base material, and resin particles. The resin particles are melamine resin particles, and image loss due to continuous use can be suppressed as compared with the case where the resin particles are contained in the elastic layer so that the resin particles are exposed from the surface of the elastic layer. A belt for an image forming apparatus is provided.

According to the invention according to <2>, there is provided a belt for an image forming apparatus capable of suppressing image omission due to continuous use as compared with the case where the average particle size of the self-healing resin particles is less than 5 μm or more than 20 μm. NS.

According to the invention according to <4>, the particles containing the acrylic urethane resin have a Martens hardness of ^{less than 0.5 N / mm 2} or more than 220 N / mm ² at 23 ° C, or a return rate at 23 ° C. An image forming apparatus belt capable of suppressing image omission due to continuous use as compared with the case where it is less than 70% is provided.

According to the invention according to <5>, the acrylic urethane resin is a reaction product of a hydroxyl group-containing acrylic resin (a), a polyol (b), and an isocyanate (c), and the polyol (b) is Compared with the case where the polyol has a single hydroxyl group, or the hydroxyl group is a polyol via a carbon chain having less than 6 carbon atoms, or the isocyanate (c) is a monofunctional isocyanate, image omission due to continuous use is eliminated. An image forming apparatus belt that can be suppressed is provided.

According to the invention according to <6>, the abundance ratio of the self-healing resin particles exposed from the surface of the surface layer or the elastic layer is ^{less than 400 particles / mm 2} or more than 40,000 ^{particles / mm 2.} In comparison, an image forming apparatus belt capable of suppressing image omission due to continuous use is provided.

According to the invention according to <7>, there is provided a belt for an image forming apparatus capable of suppressing image omission due to continuous use as compared with the case where the thickness of the surface layer is less than 1.0 μm or more than 20.0 μm. ..

According to the invention according to <8>, image formation capable of suppressing image omission due to continuous use can be suppressed as compared with the case where the surface roughness Ra of the surface layer or the elastic layer is less than 0.1 μm or more than 10.0 μm. Equipment belts are provided.

According to the invention according to <11>, it has a base material, an elastic layer provided on the base material, and resin particles, and the resin particles are melamine resin particles, and the surface of the elastic layer An image forming apparatus capable of suppressing image omission due to continuous use is provided as compared with an image forming apparatus provided with an image forming apparatus belt containing the resin particles in the elastic layer so that the resin particles are exposed.

It is sectional drawing which shows an example of the layer structure of the belt for an image forming apparatus which concerns on this embodiment. It is sectional drawing which shows an example of the layer structure of the belt for an image forming apparatus which concerns on this embodiment. It is a schematic block diagram which shows an example of the image forming apparatus which concerns on this embodiment.

Hereinafter, embodiments that are an example of the present invention will be described. These descriptions and examples illustrate embodiments and do not limit the scope of the invention.
In the numerical range described stepwise in the present specification, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical range described stepwise. good. Further, in the numerical range described in the present specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.

Each component may contain a plurality of applicable substances.
When referring to the amount of each component in the composition, if there are multiple substances corresponding to each component in the composition, unless otherwise specified, the sum of the multiple substances present in the composition. Means quantity.

<Belt for image forming device>
The belt for an image forming apparatus according to the present embodiment includes, for example, a base material 70, an elastic layer 72 provided on the base material 70, and self-healing resin particles 76, as shown in FIGS. 1 and 2. Has.
As shown in FIG. 1, when the surface layer 74 is provided on the elastic layer 72, the self-healing resin particles 76 are exposed from the surface of the surface layer 74, and the surface layer 74 has the self-healing property. Contains resin particles 76.
As shown in FIG. 2, when the elastic layer 72 does not have a surface layer, the elastic layer 72 has the self-healing property in a state where the self-repairing resin particles 76 are exposed from the surface of the elastic layer 72. Contains resin particles 76.

With the above configuration, the image forming apparatus belt according to the present embodiment suppresses image omission due to continuous use. The reason is presumed as follows.

Conventionally, the base material, an elastic layer provided on the base material, and resin particles are provided, and the resin particles are contained in the elastic layer so that the resin particles are exposed from the surface of the elastic layer. In the belt for an image forming apparatus, image omission may occur due to continuous use.
The self-healing resin particles 76 existing on the surface of the image forming apparatus belt according to the present embodiment have flexibility. Therefore, the surface of the image forming apparatus belt has followability, the generation of partial voids during transfer can be reduced, and image omission is suppressed.
Further, the self-healing resin particles 76 existing on the surface of the image forming apparatus belt have self-healing properties. Therefore, the surface condition is unlikely to change due to use, and the effect of suppressing image omission is unlikely to decrease even after continuous use.

Therefore, the image forming apparatus belt according to the present embodiment suppresses image omission due to continuous use.

Hereinafter, the details of the belt for the image forming apparatus according to the present embodiment will be described. The reference numerals will be omitted.
(Base material)
The base material contains a resin and, if necessary, a conductive agent.
Examples of the resin include a polyimide resin, a fluororesin, a fluoropolyimide resin, a polyamide resin, a polyamideimide resin, a polyether ether ester resin, a polyarylate resin, and a polyester resin.

As the resin, a thermosetting resin is preferable, and a polyimide resin is particularly preferable.
Examples of the polyimide resin include an imidized polyamic acid which is a polymer of a tetracarboxylic acid dianhydride and a diamine compound. Specifically, for example, the polyimide resin was obtained by polymerizing an equimolar amount of a tetracarboxylic acid dianhydride and a diamine compound in a solvent to obtain a polyamic acid solution, and imidizing the polyamic acid. It is a thing.

The content of the resin is, for example, preferably 10% by mass or more and 80% by mass or less, more preferably 20% by mass or more and 75% by mass or less, and 40% by mass, based on the total components constituting the base material. It is more preferably 70% by mass or less.
The resin may be used alone or in combination of two or more.

The conductive agent, conductive (e.g. a volume resistivity of less than 10 ⁷ Ω · cm, the following is the same) or semi-conductive (e.g., a volume resistivity of 10 ⁷ Ω · cm or more ^{10 13 Ω} · cm or less, and so on ) Powder (preferably a powder composed of particles having a primary particle size of less than 10 μm, preferably a powder composed of particles having a primary particle size of 1 μm or less).
The conductive agent is not particularly limited, but for example, carbon black (for example, Ketjen black, acetylene black, carbon black whose surface has been oxidized), metal (for example, aluminum or nickel), metal oxide compound (for example, oxidation). Examples thereof include yttrium, tin oxide, etc.), ionic conductive substances (for example, potassium titanate, LiCl, etc.), conductive polymers (for example, polyaniline, polypyrrole, polysulfone, polyacetylene, etc.) and the like.

The content of the conductive agent is, for example, preferably 1% by mass or more and 50% by mass or less, more preferably 2% by mass or more and 40% by mass or less, based on 4% by mass, based on the total components constituting the base material. It is more preferably% or more and 30% by mass or less.
The conductive agent may be used alone or in combination of two or more.

The base material may contain additives other than the conductive agent.
Other additives include, for example, foaming agents, foaming aids, softeners, plasticizers, curing agents, cross-linking agents, cross-linking accelerators, antioxidants, surfactants, coupling agents, fillers (silica, calcium carbonate). Known materials that can be added to the substrate, such as calcium), can be mentioned.

The thickness of the base material is preferably 30 μm to 150 μm, more preferably 40 μm to 120 μm, and even more preferably 50 μm to 80 μm.

The thickness of the substrate is measured using, for example, a micrometer and an eddy current film thickness meter.

(Elastic layer)
The elastic layer contains a rubber material and may optionally contain a conductive agent and other additives.
Examples of the rubber material include at least one selected from the group consisting of elastomers and rubbers.
Examples of the elastomer include butadiene-based polymers, styrene-butadiene-based polymers, styrene-isoprene-based polymers, vinyl chloride-based polymers, olefin-based polymers, urethane-based polymers, polyester-based polymers, nitrile-based polymers, and polyamide-based polymers. These may be homopolymers or may be in the form of copolymers or polymer blends. These polymers may be used as a mixture of two or more polymers.
The rubbers include acrylic rubber, epichlorohydrin rubber, urethane rubber, nitrile rubber, isoprene rubber, butadiene rubber, epichlorohydrin-ethylene oxide rubber, ethylene-propylene-diene rubber (EPDM), styrene-butadiene rubber (SBR), chlorinated polyisoprene, and acrylonitrile. -Butadiene rubber (NBR), chloroprene rubber, hydride polybutadiene, butyl rubber, silicone rubber and the like, or a mixed material of two or more of these can be mentioned.
Among these, the elastic layer preferably contains acrylic rubber.

The content of the rubber material is, for example, preferably 30% by mass or more and 90% by mass or less, more preferably 40% by mass or more and 80% by mass or less, and 50% by mass with respect to the total components constituting the elastic layer. It is more preferably% or more and 70% by mass or less.

Examples of the conductive agent include an electron conductive agent and an ionic conductive agent.

Examples of the electronic conductive agent include carbon black such as Ketjen black and acetylene black; thermally decomposed carbon, graphite; metals or alloys such as aluminum, copper, nickel and stainless steel; tin oxide, indium oxide, titanium oxide and tin oxide. Examples thereof include powders such as conductive metal oxides such as -antimon oxide solid solution and tin oxide-indium oxide solid solution; a substance in which the surface of an insulating material is conductive-treated. One type of electronic conductive agent may be used alone, or two or more types may be used in combination.

The content of the electronic conductive agent is preferably 1 part by mass or more and 30 parts by mass or less, and more preferably 15 parts by mass or more and 25 parts by mass or less with respect to 100 parts by mass of the rubber material.

Examples of the ionic conductive agent include quaternary ammonium salts (for example, lauryltrimethylammonium, stearyltrimethylammonium, octadodecyltrimethylammonium, dodecyltrimethylammonium, hexadecyltrimethylammonium or perchlorate of modified fatty acid dimethylethylammonium, chlorine. Acid salt, borohydrofluoride salt, sulfate, etosulfate salt, benzyl bromide salt or benzyl chloride salt), aliphatic sulfonate, higher alcohol sulfate, higher alcohol ethylene oxide-added sulfate, higher alcohol phosphoric acid Examples thereof include ester salts, higher alcohol ethylene oxide-added phosphoric acid ester salts, betaine, higher alcohol ethylene oxide, polyethylene glycol fatty acid esters, and polyhydric alcohol fatty acid esters. One type of ionic conductive agent may be used alone, or two or more types may be used in combination.

The content of the ionic conductive agent is preferably 0.1 part by mass or more and 5.0 parts by mass or less, and more preferably 0.5 parts by mass or more and 3.0 parts by mass or less with respect to 100 parts by mass of the rubber material.

Other additives include, for example, foaming agents, foaming aids, softeners, plasticizers, hardeners, cross-linking agents, cross-linking accelerators, antioxidants, surfactants, coupling agents, fillers (silica, calcium carbonate). Examples thereof include known materials that can be added to the elastic layer, such as calcium).

The thickness of the elastic layer is preferably 25 μm or more and 150 μm or less, more preferably 50 μm or more and 100 μm or less, and further preferably 70 μm or more and 80 μm or less.

(Self-healing resin particles)
The self-healing resin particles preferably contain an acrylic urethane resin as a main component from the viewpoint of obtaining a belt for an image forming apparatus capable of suppressing image omission due to continuous use.
Here, "self-healing property" refers to the property of restoring the strain created by stress when the stress is unloaded.
The "acrylic urethane resin" refers to a resin having a segment derived from an acrylic resin in its molecular structure and having a urethane bond (-NHCOO-). Specifically, the acrylic urethane resin is acrylic. monomer (e.g. a monomer represented by the following formula (ac)) comprises at least, and a vinyl group (e.g., _{^{"(R B) 2 -C = C-}} (R B) - " of the group represented by still wherein R ^B are each independently a hydrogen atom, a fluorine atom, or C 1 to 8 alkyl group (e.g. methyl group, ethyl group, etc.) represents a) a polymerizable monomer which may contain a monomer having a carbon It refers to a resin having a segment derived from an acrylic resin obtained by polymerizing a body group in its molecular structure and having a urethane bond (-NHCOO-).
"Formula ac: (Rac ^1- ) ₂ C = C (-Rac ¹ ) (-COO-Rac ² )"
(In the formula ac, Rac ¹ independently represents a hydrogen atom or an alkyl group having 1 or more and 8 or less carbon atoms (for example, a methyl group, an ethyl group, etc.). Rac ² represents an organic group. Examples of the group include an organic group containing at least one atom selected from the atomic group consisting of C, H, O, and N, for example, a hydrocarbon group (alkyl group, aryl group, etc.), fluoride. Examples thereof include an alkyl group (perfluoroalkyl group, etc.). The hydrocarbon group and the fluorinated alkyl group further include a substituent and a hetero atom (for example, −OH, −O−, −C (= O) −, −C. (= O) -O-etc.).

Here, the main component means that the content of the self-healing resin particles is the highest in terms of mass ratio.
In the present embodiment, the self-healing resin particles preferably contain acrylic urethane resin as a main component, but the content thereof is preferably 50% by mass or more and 100% by mass or less with respect to the entire resin particles. It is more preferably mass% or more and 100 mass% or less.

The acrylic urethane resin can be obtained, for example, by reacting an acrylic resin (hydroxyl group-containing acrylic resin) (a) containing a hydroxyl group in its molecular structure with a polyfunctional isocyanate (c) having a plurality of isocyanate groups.

The acrylic urethane resin has a hydroxyl group-containing acrylic resin (a) and a plurality of hydroxyl groups, and the hydroxyl group has 6 carbon atoms, from the viewpoint of obtaining a belt for an image forming apparatus capable of suppressing image omission due to continuous use. More preferably, it is a reaction product of the above-mentioned polyol (long-chain polyol) (b) via a carbon chain and the polyfunctional isocyanate (c).
Further, from the viewpoint of obtaining a belt for an image forming apparatus capable of suppressing image omission due to continuous use, the acrylic urethane resin contains the above (a), (b), and (c) in a total of 90% by mass with respect to the entire polymerization component. It is more preferable that it is a reaction product of the polymerization component group containing the above.

(A) Hydroxy Group-Containing Acrylic Resin In the present embodiment, a hydroxyl group-containing acrylic resin (a) having a hydroxyl group (−OH) is used as a raw material for the acrylic urethane resin. The hydroxyl group (-OH) contained in the hydroxyl group-containing acrylic resin (a) may be in the form of a carboxy group (-COOH).

The hydroxyl group is introduced by using, for example, a polymerizable monomer having a hydroxyl group as a polymerizable monomer as a raw material of the hydroxyl group-containing acrylic resin (a).
Examples of the polymerizable monomer having a hydroxyl group include hydroxymethyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, and N-methylol. Examples thereof include (1) an ethylenically polymerizable monomer having a hydroxyl group such as acrylic amine.
Further, (2) ethylenically polymerizable monomers having a carboxy group such as (meth) acrylic acid, crotonic acid, itaconic acid, fumaric acid, and maleic acid may be used.

Further, a polymerizable monomer having no hydroxyl group may be used in combination with the polymerizable monomer used as the raw material of the hydroxyl group-containing acrylic resin (a). Examples of the polymerizable monomer having no hydroxyl group include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, n-propyl (meth) acrylate, and the like. (Meta) acrylic acids such as n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, and n-dodecyl (meth) acrylate. Alkyl esters; vinyl halides such as vinyl chloride and vinyl bromide; vinyl cyanide such as acryliconitrile and methacrylonitrile; vinyl esters such as vinyl formate, vinyl acetate and vinyl propionate; styrene, vinyl toluene, α-methylstyrene and the like Aromatic vinyl derivatives; vinylidene halides such as vinylidene chloride and vinylidene fluoride; acrylic acids such as acrylic acid, sodium acrylate and calcium acrylate and salts thereof; β-hydroxyethyl acrylate, dimethylaminoethyl acrylate, acrylic Acrylic acid alkyl ester derivatives such as glycidyl acid, acrylamide, N-methylol acrylamide; methacrylic acid such as methacrylic acid, sodium methacrylate, calcium methacrylate and salts thereof; methacrylic acid, β-hydroxyethyl methacrylate, dimethyl methacrylate Acrylic acid methacrylate derivatives such as aminoethyl and glycidyl methacrylate; acid anhydrides such as maleic anhydride, methylmaleimide and phenylmaleimide and imides, etc., together with the polymerizable monomers (1) and (2). Examples thereof include ethylenically polymerizable monomers that can be polymerized.

As used herein, the term "(meth) acrylic acid" means to include both acrylic acid and methacrylic acid, and the term "(meth) acrylate" means to include both acrylate and methacrylate.

Here, the hydroxyl group-containing acrylic resin (a) includes, for example, a reactant of a polymerizable monomer group containing at least an acrylic monomer and may contain a monomer having a vinyl group. The reaction product has a main chain formed by polymerizing the ethylenic double bond portion of each polymerizable monomer and a side chain bonded to the main chain.
When the acrylic urethane resin contained in the resin particles is a reaction product of the hydroxyl group-containing acrylic resin (a), the long-chain polyol (b), and the polyfunctional isocyanate (c), the hydroxyl group-containing acrylic resin ( a) refers to a side chain having a hydroxyl group and having less than 10 carbon atoms (the number of carbon atoms in the side chain portion) (hereinafter, also referred to as “short side chain hydroxyl group”) in the entire side chain having a hydroxyl group. , The content ratio (molar ratio) of a side chain having a hydroxyl group and having 10 or more carbon atoms (the number of carbon atoms in the side chain portion) (hereinafter, also referred to as "long side chain hydroxyl group") is less than 1/3. You may.
The hydroxyl group-containing acrylic resin (a) has a structure in which the ratio of the long side chain hydroxyl group to the short side chain hydroxyl group is less than 1/3, that is, the number of long side chain hydroxyl groups is smaller than that of the short side chain hydroxyl group. However, by further using the long-chain polyol (b), the return rate in the acrylic urethane resin tends to be large and the maltens hardness tends to be small. Then, it becomes easy to obtain a belt for an image forming apparatus capable of suppressing image omission due to continuous use. As the amount of the long-chain polyol (b) used increases, the return rate of the acrylic urethane resin tends to increase and the Martens hardness tends to decrease.

The number of carbon atoms in the side chain portion of the short side chain hydroxyl group is less than 10, preferably 6 or less. The number of carbon atoms in the side chain portion of the long side chain hydroxyl group is 10 or more, preferably 15 or more.
Examples of the polymerizable monomer for introducing a short-side chain hydroxyl group include hydroxymethyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxy (meth) acrylate. Butyl, N-methylolacrylic amine, (meth) acrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid and the like can be mentioned.
As the polymerizable monomer for introducing the long side chain hydroxyl group, one having a ring-opened ε-lactone ring having a structure that easily increases elasticity is preferable, and for example, ε-caprolactone of 3 mol or more and 5 mol or less is used. It is preferably added to 1 mol of hydroxymethyl (meth) acrylate.

The short side chain hydroxyl group and the long side chain hydroxyl group may both have a structure having no fluorine atom in the structure of the side chain portion.

The hydroxyl group-containing acrylic resin (a) is preferably an acrylic resin having a fluorine atom. When the hydroxyl group-containing acrylic resin (a) contains a fluorine atom in its molecular structure, it becomes easy to improve the moldability of forming the resin particles into a particle shape.
The introduction of fluorine atoms into the hydroxyl group-containing acrylic resin (a) is carried out, for example, by using a polymerizable monomer having a fluorine atom as a polymerizable monomer as a raw material of the hydroxyl group-containing acrylic resin (a). It is said. Specifically, it can be introduced by a polymerizable monomer having a group containing a fluorine atom and a vinyl group.
Note that the vinyl group _{^{"(R B -) 2 C =}} C (-R B) - " (wherein ^{R B} each independently represent a hydrogen atom, a fluorine atom, or C 1 to 8 an alkyl group having a carbon ) Refers to the group represented by the structural formula. The R ^B, a hydrogen atom, a fluorine atom, or a methyl group is preferable. Examples of vinyl groups in the present specification include groups such as CH ₂ = CH-, CH ₂ = C (CH ₃ )-, and CF ₂ = CF-.

As the polymerizable monomer having a group containing a fluorine atom and a vinyl group, known ones can be used, and specific examples thereof include trifluoromethyl (meth) acrylate and 2,2,2-trifluoroethyl (meth). ) Acrylate, 1,1,1,3,3,3-hexafluoro-2-propyl (meth) acrylate, perfluoroethylmethyl (meth) acrylate, perfluoropropylmethyl (meth) acrylate, polyperfluorobutylmethyl ( Meta) acrylate, perfluoropentylmethyl (meth) acrylate, perfluorohexylmethyl (meth) acrylate, perfluoroheptylmethyl (meth) acrylate, perfluorooctylmethyl (meth) acrylate, perfluorononylmethyl (meth) acrylate, per Fluorodecylmethyl (meth) acrylate, perfluoroundecylmethyl (meth) acrylate, perfluorododecylmethyl (meth) acrylate, perfluorotridecylmethyl (meth) acrylate, perfluorotetradecylmethyl (meth) acrylate, 2-( Trifluoromethyl) ethyl (meth) acrylate, 2- (perfluoroethyl) ethyl (meth) acrylate, 2- (perfluoropropyl) ethyl (meth) acrylate, 2- (perfluorobutyl) ethyl (meth) acrylate, 2 -(Perfluoropentyl) ethyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acrylate, 2- (perfluoroheptyl) ethyl (meth) acrylate, 2- (perfluorooctyl) ethyl (meth) acrylate , 2- (Perfluorononyl) ethyl (meth) acrylate, 2- (perfluorotridecyl) ethyl (meth) acrylate, 2- (perfluorotetradecyl) ethyl (meth) acrylate, perfluorohexylethylene, hexafluoropropene , Hexafluoropropene epoxiside, perfluoro (propyl vinyl ether) and the like.

Further, in the hydroxyl group-containing acrylic resin (a), it is preferable that the side chain having a fluorine atom does not have a group that reacts with the long chain polyol (b) and the polyfunctional isocyanate (c). Therefore, the polymerizable monomer having a fluorine atom, which is a raw material of the hydroxyl group-containing acrylic resin (a), does not have a group that reacts with (b) and (c), or (b) and (c). It is preferable to use a polymerizable monomer in which the group that reacts with the above does not remain after polymerization.

Examples of the number of carbon atoms in the side chain having a fluorine atom include 2 or more and 20 or less. Further, the carbon chain in the side chain having a fluorine atom may be linear or branched.
The number of fluorine atoms contained in one molecule of the polymerizable monomer having a fluorine atom is not particularly limited, but is preferably 1 or more and 25 or less, and more preferably 3 or more and 17 or less.

In the self-healing resin particles, the content of fluorine atoms is preferably 0.5% by mass or more and 15% by mass or less, and 1% by mass or more and 10% by mass or less with respect to the entire self-healing resin particles. Is more preferable, and 2% by mass or more and 10% by mass or less is further preferable.
When it is 0.5% by mass or more, the moldability for forming the self-healing resin particles into a particle shape is easily enhanced. On the other hand, when it is 15% by mass or less, it becomes easy to obtain a belt for an image forming apparatus capable of suppressing image omission due to continuous use.
The content of fluorine atoms in the self-healing resin particles is the ratio of the polymerizable monomer having a fluorine atom in the total polymerizable monomer for synthesizing the hydroxyl group-containing acrylic resin (a), and the hydroxyl group-containing acrylic. It is adjusted by the ratio of the resin (a) and other components (long-chain polyol (b), polyfunctional isocyanate (c), etc.) and the like.

The content of fluorine atoms in the self-repairing resin particles is measured by an X-ray photoelectron spectroscopy (XPS) method while etching the self-repairing resin particles with cluster argon.

The hydroxyl value of the hydroxyl group-containing acrylic resin (a) is preferably 40 mgKOH / g or more and 280 mgKOH / g or less, and more preferably 70 mgKOH / g or more and 200 mgKOH / g or less.
When the hydroxyl value is 40 mgKOH / g or more, the acrylic urethane resin having a high crosslink density is polymerized, and it becomes easy to obtain a belt for an image forming apparatus capable of suppressing image omission due to continuous use. On the other hand, when the amount is 280 mgKOH / g or less, an acrylic urethane resin having appropriate flexibility can be obtained.
The hydroxyl value of the hydroxyl group-containing acrylic resin (a) is adjusted by the ratio of the polymerizable monomer having a hydroxyl group in the total polymerizable monomer for synthesizing the hydroxyl group-containing acrylic resin (a).

The hydroxyl value represents the number of mg of potassium hydroxide required for acetylating a hydroxyl group (hydroxyl group) in 1 g of a sample. The hydroxyl value in this embodiment is measured according to the method (potentiometric titration method) defined in JIS K0070-1992. However, if the sample does not dissolve, a solvent such as dioxane or tetrahydrofuran (THF) is used as the solvent.

The weight average molecular weight of the hydroxyl group-containing acrylic resin (a) is preferably 5000 or more and 100,000 or less, and more preferably 10,000 or more and 50,000 or less.
When the weight average molecular weight of the hydroxyl group-containing acrylic resin (a) is 5000 or more, it becomes easy to obtain a belt for an image forming apparatus capable of suppressing image omission due to continuous use. On the other hand, when the weight average molecular weight is 100,000 or less, it becomes easy to obtain resin particles having excellent flexibility.

The weight average molecular weight of the hydroxyl group-containing acrylic resin (a) is measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC is carried out using a Tosoh GPC / HLC-8120 GPC as a measuring device, a Tosoh column / TSKgel SuperHM-M (15 cm), and a tetrahydrofuran (THF) solvent. The weight average molecular weight is calculated from this measurement result using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample.

The hydroxyl group-containing acrylic resin (a) is synthesized, for example, by mixing the above-mentioned polymerizable monomers, performing ordinary radical polymerization, ionic polymerization, or the like, and then purifying the resin.

(B) Long-chain polyol A long-chain polyol is a carbon chain having a plurality of hydroxyl groups (-OH) and having 6 or more carbon atoms (the number of carbon atoms in the linear portion connecting the hydroxyl groups). It is a polyol via. That is, a long-chain polyol is a polyol in which all hydroxyl groups are linked by carbon chains having 6 or more carbon atoms (the number of carbon atoms in the linear portion connecting the hydroxyl groups).

The number of functional groups (that is, the number of hydroxyl groups contained in one molecule of the long-chain polyol) of the long-chain polyol may be, for example, in the range of 2 or more and 5 or less, and may be 2 or more and 3 or less.

The carbon chain having 6 or more carbon atoms in the long chain polyol represents a chain having 6 or more carbon atoms in the linear portion connecting the hydroxyl groups. As the carbon chain having 6 or more carbon atoms, one selected from an alkylene group or one or more alkylene groups and -O-, -C (= O)-, and -C (= O) -O-. A divalent group formed by combining the above groups can be mentioned. A long-chain polyol having a hydroxyl group via a carbon chain having 6 or more carbon atoms is − [CO (CH ₂ ) _n1 O] _n2 −H (where n1 is 1 or more and 10 or less (preferably 3 or more and 6 or less, more preferably). 5), and n2 preferably has a structure of 1 or more and 50 or less (preferably 1 or more and 35 or less, more preferably 1 or more and 10 or less).

Examples of the long-chain polyol include bifunctional polycaprolactone diol, trifunctional polycaprolactone triol, and tetrafunctional or higher functional polycaprolactone polyol.

As the bifunctional polycaprolactone diol, for example, − [CO (CH ₂ ) _n11 O] _n12 −H (where n11 represents 1 or more and 10 or less (preferably 3 or more and 6 or less, more preferably 5), n12 represents. Examples thereof include a compound having two groups having a hydroxyl group at the terminal, which is represented by 1 or more and 50 or less (preferably 4 or more and 35 or less). Of these, the compound represented by the following general formula (1) is preferable.

(In the general formula (1), R represents an alkylene group or a divalent group formed by combining an alkylene group with one or more groups selected from −O− and −C (= O) −. m and n each independently represent an integer of 1 or more and 35 or less.)

In the general formula (1), the alkylene group contained in the divalent group represented by R may be linear or branched. As the alkylene group, for example, an alkylene group having 1 or more and 10 or less carbon atoms is preferable, and an alkylene group having 1 or more and 5 or less carbon atoms is more preferable.
As the divalent group represented by R, a linear or branched alkylene group having 1 or more and 10 or less carbon atoms (preferably 2 or more and 5 or less carbon atoms) is preferable, and 1 or more and 5 or less carbon atoms. A group in which two linear or branched alkylene groups (preferably having 1 or more and 3 or less carbon atoms) are linked by −O− or −C (= O) − (preferably −O−) is preferable. .. Among _{these, * - C 2 H 4 -} *, * - C 2 H 4 OC 2 H 4 - *, or _{* -C (CH 3) 2 -} (CH 2) 2 - * a divalent represented Groups are more preferred. The divalent groups listed above are bound at the "*" portion.
m and n each independently represent an integer of 1 or more and 35 or less, and preferably 2 or more and 10 or less.

As the trifunctional polycaprolactone diol, for example, − [CO (CH ₂ ) _n21 O] _n22 −H (where n21 represents 1 or more and 10 or less (preferably 3 or more and 6 or less, more preferably 5), n22 represents. Examples thereof include compounds having three groups having a hydroxyl group at the terminal, which are represented by 1 or more and 50 or less (preferably 1 or more and 28 or less). Of these, the compound represented by the following general formula (2) is preferable.

(In the general formula (2), R is a trivalent group obtained by removing one hydrogen atom from an alkylene group, or a trivalent group obtained by removing one hydrogen atom from an alkylene group, and an alkylene group, —O—, and It represents a trivalent group consisting of a combination of one or more groups selected from −C (= O) −. L, m, and n each independently represent an integer of 1 or more and 28 or less, and l + m + n is 3. More than 30 or less.)

In the general formula (2), when R represents a trivalent group obtained by removing one hydrogen atom from an alkylene group, the group may be linear or branched. As the trivalent group obtained by removing one hydrogen atom from the alkylene group, for example, an alkylene group having 1 or more and 10 or less carbon atoms is preferable, and an alkylene group having 1 or more and 6 or less carbon atoms is more preferable.
Further, R is a trivalent group obtained by removing one hydrogen atom from the alkylene group shown above, an alkylene group (for example, an alkylene group having 1 or more and 10 or less carbon atoms), -O-, and -C (= O). It may be a trivalent group formed by combining one or more groups selected from −.
The trivalent group represented by R is a trivalent group obtained by removing one hydrogen atom from a linear or branched alkylene group having 1 or more and 10 or less carbon atoms (preferably 3 or more and 6 or less carbon atoms). Group is preferred. Among these, * _{-CH 2-} CH (-*) -CH _2- *, CH _3- C (-*) (-*)-(CH ₂ ) _2- *, CH ₃ CH ₂ C (-*) _{(- *) (CH 2)} 3 - * 3 -valent group represented by is more preferable. The trivalent groups listed above are bound at the "*" portion.
l, m, and n each independently represent an integer of 1 or more and 28 or less, and preferably 2 or more and 10 or less. l + m + n is 3 or more and 30 or less, and preferably 6 or more and 30 or less.

The long-chain polyol preferably has a hydroxyl value of 30 mgKOH / g or more and 300 mgKOH / g or less, and more preferably 50 mgKOH / g or more and 250 mgKOH / g or less. When the hydroxyl value is 30 mgKOH / g or more, the acrylic urethane resin having a high crosslink density is polymerized, while when it is 300 mgKOH / g or less, an acrylic urethane resin having appropriate flexibility can be easily obtained.

The hydroxyl value represents the number of mg of potassium hydroxide required to acetylate a hydroxyl group (hydroxyl group) in 1 g of a sample. The measurement of the hydroxyl value in the present embodiment is performed according to the method (potentiometric titration method) defined in JIS K0070-1992. However, if the sample does not dissolve, a solvent such as dioxane or THF is used as the solvent.

The hydroxyl value of the hydroxyl group-containing acrylic resin (a) and [OH _A], the ratio of the hydroxyl value of the long chain polyol _{(b) [OH B] [} OH A / OH B] is 0.1 to 3 It is preferable, it is more preferably 0.2 or more and 2.5 or less, and further preferably 0.3 or more and 2.0 or less.

(C) Polyfunctional isocyanate The polyfunctional isocyanate (c) is a compound having a plurality of isocyanate groups (-NCO), for example, a hydroxyl group contained in a hydroxyl group-containing acrylic resin (a) and a hydroxyl group contained in a long-chain polyol (b). Etc. to form a urethane bond (-NHCOO-). Then, it functions as a cross-linking agent for cross-linking the hydroxyl group-containing acrylic resin (a) with each other, the hydroxyl group-containing acrylic resin (a) with the long-chain polyol (b), and the long-chain polyol (b) with each other.

The polyfunctional isocyanate is not particularly limited, and examples thereof include bifunctional diisocyanates such as methylene diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. Further, a polyfunctional isocyanate which is a multimer of hexamethylene polyisocyanate and has a burette structure, an isocyanurate structure, an adduct structure, an elastic structure and the like is also preferably used.
A commercially available product may be used as the polyfunctional isocyanate, and examples thereof include polyisocyanate (duranate) manufactured by Asahi Kasei Corporation.
Only one type of polyfunctional isocyanate may be used, or two or more types may be mixed and used.

As for the amount of polyfunctional isocyanate, the ratio of the isocyanate group (-NCO) to the total amount of the hydroxyl groups (-OH) in the hydroxyl group-containing acrylic resin (a) and the long-chain polyol (b) is 0 in terms of molar ratio. The amount is preferably adjusted to be .8 or more and 1.5 or less, and more preferably 1 or more and 1.3 or less in terms of molar ratio.

(E) Other Additives In the present embodiment, the self-healing resin particles may contain other additives. For example, other additives include a colorant, an antistatic agent, a hydroxyl group-containing acrylic resin (a), a hydroxyl group (-OH) in a long-chain polyol (b), and an isocyanate group (-OH) in a polyfunctional isocyanate (c). Examples thereof include a reaction accelerator that promotes a reaction with NCO).

-Colorants Examples of colorants include carbon black, chrome yellow, hanza yellow, benzidine yellow, slene yellow, quinoline yellow, pigment yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, permanent red, and brilliant carmine. 3B, Brilliant Carmin 6B, Dupont Oil Red, Pyrazolon Red, Resole Red, Rhodamin B Lake, Lake Red C, Pigment Red, Rose Bengal, Aniline Blue, Ultra Marine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Pigment Blue, Various pigments such as phthalocyanine green and malakite green oxalate, or aclysine-based, xanthene-based, azo-based, benzoquinone-based, azine-based, anthraquinone-based, thioindico-based, dioxazine-based, thiazine-based, azomethine-based, indico-based, phthalocyanine-based , Aniline black type, polymethine type, triphenylmethane type, diphenylmethane type, thiazole type and various other dyes.

As the colorant, a surface-treated colorant may be used if necessary, or may be used in combination with a dispersant. Further, a plurality of kinds of colorants may be used in combination.

The content of the colorant is, for example, preferably 1.0% by mass or more and 40% by mass or less, and more preferably 2.0% by mass or more and 30% by mass or less with respect to the entire self-healing resin particles.

-Antistatic agents Specific examples of antistatic agents include cationic surfactants (for example, tetraalkylammonium salts, trialkylbenzylammonium salts, alkylamine hydrochlorides, imidazolium salts, etc.), and anionic surfactants. (For example, alkyl sulfonate, alkyl benzene sulfonate, alkyl phosphate, etc.), non-ionic surfactant compounds (eg, glycerin fatty acid ester, polyoxyalkylene ether, polyoxyethylene alkyl phenyl ether, N, N-bis-2) -Hydroxyethyl alkylamine, hydroxyalkyl monoethanolamine, polyoxyethylene alkylamine, fatty acid diethanolamide, polyoxyethylene alkylamine fatty acid ester, etc.), amphoteric surfactant compounds (eg, alkylbetaine, alkylimidazolium betaine, etc.), etc. Can be mentioned.

Moreover, as an antistatic agent, the thing containing quaternary ammonium can be mentioned.
Specifically, tri-n-butylmethylammonium bistrifluoromethanesulfonimide, lauryltrimethylammonium chloride, octyldimethylethylammonium ethyl sulfate, didecyldimethylammonium chloride, lauryldimethylbenzylammonium chloride, stearyldimethylhydroxyethylammonium paratoluene Examples thereof include phonate, tributylbenzylammonium chloride, lauryldimethylaminoacetate betaine, lauric acid amide propyl betaine, octanoate amide propyl betaine, and hydrochloride of polyoxyethylene stearylamine. Among these, tri-n-butylmethylammonium bistrifluoromethanesulfonimide is preferable.

Further, a high molecular weight antistatic agent may be used.
Examples of the high molecular weight antistatic agent include a polymer compound obtained by polymerizing a quaternary ammonium base-containing acrylate, a polystyrene sulfonic acid type polymer compound, a polycarboxylic acid type polymer compound, a polyether ester type polymer compound, and ethylene oxide. Examples thereof include epichlorohydrin type polymer compounds and polyether ester amide type polymer compounds.

Examples of the polymer compound obtained by polymerizing the quaternary ammonium base-containing acrylate include a polymer compound having at least the following structural unit (A).

(In the structural unit (A), R ¹ represents a hydrogen atom or a methyl group, R ² , R ³ and R ⁴ each independently represent an alkyl group, and X ⁻ represents an anion.)

The polymerization of the high molecular weight antistatic agent can be carried out by a known method.
As the high molecular weight antistatic agent, only the polymer compound composed of the same polymerizable monomer may be used, or two or more kinds of polymer compounds composed of different polymerizable monomers may be used in combination.

In this embodiment, it is preferable to adjust the surface resistance of the belt for the image forming apparatus to be formed in ^{the range of 1 × 10 9} Ω / □ or more and 1 × 10 ¹⁴ Ω / □ or less, and the volume resistance is It is preferable to adjust the range so that the range is 1 × 10 ⁸ Ωcm or more and 1 × 10 ^{13 Ωcm or less.}
Surface resistance and volume resistance are measured according to JIS-K6911 using a Hiresta UPMCP-450 type UR probe manufactured by Dia Instruments Co., Ltd. in an environment of 22 ° C. and 55% RH.
If the antistatic agent is contained, the surface resistance and volume resistance of the image forming apparatus belt are controlled by adjusting the type and content of the antistatic agent.

The antistatic agent may be used alone or in combination of two or more.

-Reaction accelerator A reaction accelerator that promotes the reaction between the hydroxyl group (-OH) in the hydroxyl group-containing acrylic resin (a) and the long-chain polyol (b) and the isocyanate group (-NCO) in the polyfunctional isocyanate (c). It can also be added. Examples of the accelerator include metal catalysts such as tin octylate, dibutyltin diacetate, dibutyltin dilaurate, bismuth octylate, and bismuth decanoate. For example, Neostan U-28, U-50, U-600, etc. of Nitto Kasei Co., Ltd. can be mentioned.

When the self-healing resin particles are particles containing an acrylic urethane resin, the Martens hardness at 23 ° C. ^{is preferably 0.5 N / mm 2} or more and 220 N / mm ² or less, and 1 N / mm ² or more and 80 N / mm. ^{It is more preferably 2} or less, and further preferably 1 N / mm ² or more and 5 N / mm ² or less.
When the Martens hardness (23 ° C.) is 220 N / mm ² or less, it becomes easy to obtain a belt for an image forming apparatus capable of suppressing image omission due to continuous use. On the other hand, when it is 0.5 N / mm ² or more, it becomes easy to maintain the shape required for the self-healing resin.

The self-healing resin particles have a return rate of 70% or more and 100% or less at 23 ° C., preferably 80% or more and 100% or less, and more preferably 90% or more and 100% or less.
The return rate is an index showing the self-healing property of the self-healing resin particles (the property of restoring the strain formed by stress within 1 minute after the stress is unloaded, that is, the degree of scratch repair). That is, when the return rate (23 ° C.) is 70% or more, the ease of repairing scratches (that is, self-repairing property) is improved, and it becomes easy to obtain a belt for an image forming apparatus capable of suppressing image omission due to continuous use. ..

The Martens hardness and return rate of the self-healing resin particles are measured by using a Fisherscope HM2000 (manufactured by Fisher) as a measuring device, fixing the sample to a slide glass with an adhesive, and setting the sample in the measuring device. The sample is loaded to 0.5 mN at a specific measurement temperature (eg 23 ° C.) for 15 seconds and held at 0.5 mN for 5 seconds. The maximum displacement at that time is (h1). After that, the load was unloaded to 0.005 mN over 15 seconds, and the displacement when held at 0.005 mN for 1 minute was defined as (h2), and the return rate [(h1-h2) / h1] × 100 (%) was calculated. calculate. Further, the Martens hardness can be obtained from the load displacement curve at this time.
As a sample for this measurement, when the self-healing resin particles have a size that allows the load to be directly applied by the indenter in the measuring device, the self-healing resin particles themselves (one self-healing). (Sex resin particles) is used as a sample. On the other hand, when the self-healing resin particles have a size that cannot be directly loaded by the indenter, the constituent components of the self-healing resin particles are analyzed by analysis, and the resin film (the same constituents as these constituents) is used. An average thickness of 5 μm) is formed, and this resin film is used as a sample.
Normally, if the self-healing resin particles have a volume average particle diameter D50v of 10 μm or more, a load can be directly applied by an indenter.

The Martens hardness and the return rate of the self-healing resin particles can be controlled by adjusting the composition of the acrylic urethane resin which is the main component of the self-healing resin particles. For example, the acrylic urethane resin includes a hydroxyl group-containing acrylic resin (a), a polyol (b) having a plurality of hydroxyl groups and having the hydroxyl groups via a carbon chain having 6 or more carbon atoms, and a polyfunctional isocyanate (c). Taking the case of the reaction product of and It is adjusted by controlling the ratio of (b), the number of functional groups (isocyanate groups) in the polyfunctional isocyanate (c), the ratio of the polyfunctional isocyanate (c) to the acrylic resin (a), and the like.

The volume average particle diameter D50v of the self-healing resin particles is preferably 5 μm or more and 20 μm or less, more preferably 7 μm or more and 18 μm or less, and further preferably 10 μm or more and 15 μm or less.
When the volume average particle size D50v is 5 μm or more, it becomes easy to obtain a belt for an image forming apparatus capable of suppressing image omission due to continuous use. On the other hand, when it is 20 μm or less, the followability of the belt surface for the image forming apparatus is improved.

The volume average particle size D50v of the self-healing resin particles is a scanning electron microscope (SEM) (manufactured by Hitachi High-Technologies Co., Ltd., S-4700) on the surface of the belt for an image forming apparatus in which the self-healing resin particles are exposed. An image is taken at a magnification of 40,000 times, and observed at an acceleration voltage of 15 kV, an emission current of 20 μA, and a WD of 15 mm. The identified self-healing resin particles are analyzed by the image processing analysis software WinRof (manufactured by Mitani Shoji Co., Ltd.) to obtain the equivalent circle diameter, and the particle size (circle equivalent diameter) is measured for at least 100 particles. The volume average particle size, which is the cumulative particle size of 50% from the small diameter side in the volume-based distribution of the above, is obtained.
For image analysis to determine the equivalent circle diameter of 100 self-healing resin particles to be measured, a two-dimensional image with a magnification of 10,000 times is taken using an analyzer (ERA-8900: manufactured by Elionix Inc.). Using the analysis software WinROOF (manufactured by Mitani Shoji Co., Ltd.), the projected area is calculated under the condition of 0.010000 μm / pixel, and the equivalent circle diameter is calculated by the formula: circle equivalent diameter = 2√ (projected area / π).

The content of the self-healing resin particles is, for example, when the surface layer is provided on the elastic layer and the self-healing resin particles are contained in a state where the self-healing resin particles are exposed from the surface of the surface layer, the surface layer. It is preferably 10% by mass or more and 80% by mass or less, more preferably 20% by mass or more and 70% by mass or less, and further preferably 30% by mass or more and 60% by mass or less with respect to the total components constituting the above. preferable.
The content of the self-healing resin particles is, for example, 4 when the self-healing resin particles are contained in a state where the self-healing resin particles are exposed from the surface of the elastic layer without having a surface layer on the elastic layer. It is preferably mass% or more and 40 mass% or less, more preferably 5 mass% or more and 30 mass% or less, and further preferably 6 mass% or more and 20 mass% or less.

The self-healing resin particles may be used in combination with particles other than the self-healing resin particles.

Examples of other particles include organic particles or inorganic particles.
Examples of the organic particles include particles other than self-healing resin particles such as melamine resin, acrylic resin, polyamide resin, polyester resin, silicone resin, and fluororesin.
Examples of the inorganic particles include particles such as silica, alumina, titanium oxide, calcium carbonate, magnesium carbonate, tricalcium phosphate, and cerium oxide.

The content of the other particles is, for example, preferably 10% by mass or more and 50% by mass or less, preferably 10% by mass or more and 40% by mass or less, based on the total of the self-healing resin particles and the other particles. More preferably, it is 10% by mass or more and 30% by mass or less.

(Manufacturing method of self-healing resin particles)
A method for producing self-healing resin particles containing an acrylic urethane resin as a main component will be described in detail.
The method for producing the self-healing resin particles according to the present embodiment is not limited. However, it is preferably produced by a wet production method such as a dissolution / suspension method.

-Dissolution suspension method As a dissolution suspension method for producing self-repairing resin particles according to the present embodiment, at least a polymerization component (for example, the above-mentioned hydroxyl group-containing acrylic resin (a) and long-chain polyol (b)) is contained in an organic solvent. ), Polyfunctional isocyanate (c), etc.) to prepare an oil phase, a granulation step of suspending and granulating the oil phase component in an aqueous phase, and removing a solvent. Examples thereof include a method having a solvent removing step.

(Oil phase preparation process)
In the dissolution / suspension method, first, the polymerization component (for example, the above-mentioned hydroxyl group-containing acrylic resin (a), long-chain polyol (b), polyfunctional isocyanate (c), etc.) is dissolved or dispersed in an organic solvent to dissolve or disperse the oil phase. To prepare.

The organic solvent that can be used depends on the type of polymerization component, but is generally a hydrocarbon such as toluene, xylene, hexane; a halogenated hydrocarbon such as methylene chloride, chloroform, dichloroethane; ethanol, butanol, benzyl alcohol ether, tetrahydrofuran, etc. Alcohols or ethers; esters such as methyl acetate, ethyl acetate, butyl acetate, isopropyl acetate; ketones such as acetone, methyl ethyl ketone, diisobutyl ketone, cyclohexanone, methylcyclohexane and the like are used. The mass ratio of the polymerization component to the solvent used in the oil phase is preferably in the range of 10:90 to 80:20 in terms of ease of granulation or the final yield of self-healing resin particles.

In the present embodiment, when an additive such as a colorant is added to the self-healing resin particles, the additive dispersion liquid in which the additive is previously dispersed by a sinargist and a dispersant before preparing the oil phase. Is prepared, and it is preferable to mix this with a polymerization component (for example, the above-mentioned components (a), (b), and (c), etc.). When preparing the additive dispersion liquid, first, the sinargist and the dispersant are attached to the additive. Adhesion to the additive is performed using a normal stirring device. Specifically, the additive, sinagest, and dispersant are placed in a container equipped with granular media such as an attritor, a ball mill, a sand mill, and a vibration mill, and the container is placed in a preferable temperature range, for example, 20 ° C. to 160 ° C. A method of keeping in the temperature range and stirring is used.

(Granulation process)
Next, these oil phase components are suspended and granulated so as to have a particle size required in the aqueous phase. The main medium of the aqueous phase is water, and it is preferable to mix the dispersant. Further, salt may be added to the water and used as a salt solution.
The dispersant disperses and stabilizes the oil phase droplets by forming a hydrophilic colloid. Examples of the inorganic dispersant include calcium carbonate, magnesium carbonate, barium carbonate, tricalcium phosphate, hydroxyapatite, diatom silicate soil, and clay.
Further, an organic dispersant may be used in combination with these inorganic dispersants. Specific examples of the organic dispersant include gelatin, gelatin derivatives (for example, acetylated gelatin, phthalated gelatin, succinate gelatin, etc.), proteins such as albumin and casein, corodion, gum arabic, agar, and alginic acid. Cellulose derivatives (eg alkyl esters of carboxymethyl cellulose, hydroxymethyl cellulose, carboxymethyl cellulose, etc.), synthetic polymers (eg, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylamide, polyacrylic acid salt, polymethacrylate, polymaleate, polystyrene sulfone) Acidic acid) and the like.
These dispersants may be used alone or in combination of two or more.
The dispersant is preferably used in the range of 0.001% by mass or more and 5% by mass or less with respect to the main medium of the aqueous phase.

A dispersion aid may be further used in combination with the aqueous phase. Surfactants are suitable as the dispersion aid, and examples thereof include ionic and nonionic surfactants. These dispersion aids may be used alone or in combination of two or more. The dispersion aid is preferably used in the range of 0.001% by mass or more and 5% by mass or less with respect to the main medium of the aqueous phase.

The mixing ratio of the oil phase and the aqueous phase varies depending on the particle size of the final self-healing resin particles and the manufacturing apparatus, but the oil phase / aqueous phase is in the range of 10/90 to 90/10 in terms of mass ratio. preferable. Further, the granulation of the oil phase in the aqueous phase is preferably performed under high-speed shearing. The smaller the particle size of the self-healing resin particles to be manufactured, the more attention should be paid to the selection of the disperser provided with the high-speed shearing mechanism to be used. Among them, various homomixers, homogenizers, colloid mills, ultrataraxes, clear mills and other high-speed blade rotation type and forced interval passing type emulsification dispersers are suitable.

(Solvent removal step)
The solvent (organic solvent) is removed during or after the granulation step. The solvent may be removed at room temperature (for example, 25 ° C.) or further under reduced pressure. In order to carry out at room temperature, it is desirable to apply a temperature lower than the boiling point of the solvent and considering the glass transition temperature Tg of the resin (acrylic urethane resin). If the Tg of the resin is significantly exceeded, coalescence of self-healing resin particles may occur.
For example, although it depends on the amount of the reaction accelerator added, generally, the solvent is removed by stirring at 40 ° C. for 1 hour or more and 3 hours or less, and then stirring at 60 ° C. for 2 hours or more and 6 hours or less to proceed the cross-linking reaction. It can be granulated. The pressure is preferably reduced from 20 mmHg to 150 mmHg.

The obtained granulated product (slurry) is preferably washed with an acid that solubilizes the inorganic dispersant, such as hydrochloric acid, nitric acid, formic acid, and acetic acid, after removing the solvent. As a result, the inorganic dispersant remaining on the surface of the self-healing resin particles is removed. The granulated product treated with the above acid may be washed again with alkaline water such as sodium hydroxide. By being placed in an acidic atmosphere in this way, some of the ionic substances on the surface of the self-repairing resin particles that have been insolubilized are solubilized and removed again, and the chargeability and powder fluidity are improved. In addition to adjusting conditions such as pH at the time of washing, the number of times of washing, and temperature at the time of washing, it is more preferable to use a stirrer, an ultrasonic disperser, or the like because the washing is effectively carried out. After that, steps such as filtration, decantation, and centrifugation may be carried out, and after drying, self-healing resin particles are obtained.
For drying, a conventional general drying method can be used. For example, a method using an air flow drying device can be mentioned, and for example, a drying treatment using a flash jet dryer, a treatment using a fluidized bed, and the like can be mentioned. Furthermore, the freeze-drying method can also be used. In particular, when there are no fluorine atoms, the freeze-drying method can be preferably used because it tends to aggregate in the drying step.

(Surface of belt for image forming device)
When the belt for an image forming apparatus according to the present embodiment has a surface layer on an elastic layer, the self-healing resin particles are exposed on the surface layer of the surface layer. When the elastic layer does not have a surface layer, the elastic layer contains the self-repairing resin particles in a state where the self-repairing resin particles are exposed from the surface of the elastic layer.

Here, the state in which the self-healing resin particles are exposed from the surface means a state in which the self-healing resin particles can be directly confirmed on the surface when the self-healing resin particles are observed with an electron microscope, a transmission electron microscope, or the like. means.

The abundance ratio of the self-healing resin particles exposed from the surface of the surface layer or the elastic layer may be 400 / mm ² or more and 40,000 / mm ² or less from the viewpoint of suppressing image loss due to continuous use. It is more preferably 500 pieces / mm ² or more and 30,000 pieces / mm ² or less, and further preferably 600 pieces / mm ² or more and 20,000 pieces / mm ² or less.

The abundance ratio of the self-healing resin particles exposed from the surface is measured as follows.
First, the surface of the image forming apparatus belt on which the self-healing resin particles are exposed is observed using an optical microscope (VHX-6000, manufactured by KEYENCE CORPORATION) at a magnification of 800 times. The number of the self-healing resin particles exposed from the surface in the region of 100 μm × 100 μm is counted, and the number of the ^{self-healing resin particles exposed from the surface per 1 μm 2} (that is, the unit is “pieces / μm ^2”. ") Is calculated. Then, the number of the self-healing resin particles exposed from the surface per ^{1 μm 2} obtained is converted into a unit conversion into the number of the self-healing resin particles exposed from the surface per ^{1 mm 2 (that is, the unit is "pieces / mm". 2} ”) to calculate.

The surface roughness Ra (arithmetic mean roughness) of the image forming apparatus belt is preferably 0.1 μm or more and 10.0 μm or less, and 0.5 μm or more and 8 μm or less, from the viewpoint of suppressing image omission due to continuous use. It is more preferably 1 μm or more and 5 μm or less.
Here, the surface roughness Ra is based on the JIS B0601 (1994) standard. The measuring device is SURFCOM manufactured by Tokyo Seimitsu Co., Ltd. The measurement length is 4 [mm], the cutoff wavelength is 0.8 [mm], the cutoff type is Gaussian, and the measurement speed is 0.3 [mm / s].

When the surface layer is provided on the elastic layer, the surface layer contains a resin.
The resin contained in the surface layer is, for example, at least one selected from the group consisting of polyimide resin, fluoride polyimide resin, polyamide resin, polyamideimide resin, polyether ether ester resin, polyarylate resin, polyester resin, and acrylic urethane resin. Seed resin can be mentioned.

From the viewpoint of obtaining a belt for an image forming apparatus capable of suppressing image omission due to continuous use, the resin contained in the surface layer is preferably an acrylic urethane resin, and the acrylic urethane resin is a hydroxyl group-containing acrylic resin (a). , The reaction product of a polyol (b) having a plurality of hydroxyl groups and having the hydroxyl groups via a carbon chain having 6 or more carbon atoms and a polyfunctional isocyanate (c) is preferable.
As the acrylic urethane resin, the same resin as the acrylic urethane resin described in the above (self-healing resin particles) is applied.

When the surface layer is provided on the elastic layer, the thickness of the surface layer is preferably 1.0 μm or more and 20 μm or less, and 2 μm or more and 18 μm or less, from the viewpoint of obtaining a belt for an image forming apparatus capable of suppressing image omission due to continuous use. It is more preferable that it is 3 μm or more and 15 μm or less.

Here, the thickness of the surface layer is the thickness of the portion of the surface layer in which the self-healing resin particles do not exist. That is, it refers to the thickness of the portion indicated by "t" in FIG.

For the thickness of the surface layer, the image forming apparatus belt having the surface layer is cut along the film thickness direction, the cut surface is observed at 10 points with a scanning electron microscope (SEM), and each of the 10 SEM images is used. It is obtained by measuring the thickness of the surface layer at the observation site and averaging the obtained 10 measured values.

In order to leave the surface of the image forming apparatus belt in a state where the self-healing resin particles are exposed from the surface, in the case of the image forming apparatus belt having a surface layer on the elastic layer, the elastic layer (or the elastic layer) is used. After forming the raw material layer), a coating liquid containing self-healing resin particles and a resin forming the surface layer (or a resin raw material forming the surface layer) is applied onto the elastic layer by spray coating. A method of forming a surface layer by roll-coating and coating using anix roll can be mentioned.
When the elastic layer does not have a surface layer, the elastic layer before curing is formed on the base material, and the self-healing resin particles are formed into the elastic layer before curing by a method such as roll coating using anix roll or the like. There is a method of adhering to the top and heating to cure.
When the self-healing resin particles are attached to the elastic layer before curing by using anilox roll, the self-healing resin particles may be left as powder or may be dispersed in a solvent such as acetone. good. When dispersed in a solvent, it is preferable to volatilize the solvent before embedding it on the surface of the coating film.

(Example of using a belt for an image forming apparatus)
The image forming apparatus belt according to the present embodiment can be used as an intermediate transfer belt and a paper transport belt used in an image forming apparatus such as an electrophotographic copying machine or a laser printer.
Further, the belt for an image forming apparatus according to the present embodiment can also be used as a paper transport belt and an intermediate transfer belt used in an inkjet type image forming apparatus.

The shape of the image forming apparatus belt according to the present embodiment may be endless or endless.

(Image forming device)
Next, the image forming apparatus according to this embodiment will be described.
In the following description, the electrophotographic image forming apparatus will be described, but the image forming apparatus according to the present embodiment is not limited to this, and may be, for example, an inkjet type image forming apparatus.

The image forming apparatus according to the present embodiment includes an image holder, a toner image forming means for forming a toner image on the surface of the image holder, and a transfer device, and transfers the toner image to the surface of a recording medium. Means and.

The image forming apparatus according to the present embodiment may include, for example, in the case of a secondary transfer type image forming apparatus, an image forming apparatus belt according to the present embodiment as an intermediate transfer belt.
Further, the image forming apparatus according to the present embodiment includes, for example, in the case of a direct transfer type image forming apparatus, an embodiment in which the image forming apparatus belt according to the present embodiment is provided as a paper transport belt.

Hereinafter, the image forming apparatus according to the present embodiment will be described with reference to the drawings.

FIG. 3 is a schematic configuration diagram showing the configuration of the image forming apparatus according to the present embodiment. The belt for the image forming apparatus according to the present embodiment is applied as the intermediate transfer belt.

As shown in FIG. 3, the image forming apparatus 100 according to the present embodiment is, for example, an intermediate transfer type image forming apparatus generally called a tandem type, and a plurality of toner images of each color component are formed by an electrophotographic method. Image forming units 1Y, 1M, 1C, 1K, and a primary transfer unit 10 for sequentially transferring (primary transfer) each color component toner image formed by each image forming unit 1Y, 1M, 1C, 1K to an intermediate transfer belt 15. , A secondary transfer unit 20 that collectively transfers (secondary transfer) the superimposed toner image transferred on the intermediate transfer belt 15 to paper K, which is a recording medium, and fixing that fixes the secondary transferred image on paper K. The device 60 and the like are provided. Further, the image forming apparatus 100 has a control unit 40 that controls the operation of each device (each unit).

Each image forming unit 1Y, 1M, 1C, 1K of the image forming apparatus 100 includes a photoconductor 11 that rotates in the direction of arrow A as an example of an image holder that holds a toner image formed on the surface.

A charger 12 for charging the photoconductor 11 is provided around the photoconductor 11 as an example of the charging means, and a laser exposure device for writing an electrostatic latent image on the photoconductor 11 as an example of the latent image forming means. 13 (the exposure beam in the figure is indicated by the reference numeral Bm) is provided.

Further, around the photoconductor 11, as an example of the developing means, a developer 14 in which each color component toner is accommodated and the electrostatic latent image on the photoconductor 11 is visualized by the toner is provided, and the photoconductor 11 is provided. A primary transfer roll 16 for transferring each color component toner image formed above to the intermediate transfer belt 15 by the primary transfer unit 10 is provided.

Further, a photoconductor cleaner 17 for removing residual toner on the photoconductor 11 is provided around the photoconductor 11, and a charger 12, a laser exposure device 13, a developing device 14, a primary transfer roll 16, and a photoconductor cleaner are provided. 17 electrophotographic devices are sequentially arranged along the rotation direction of the photoconductor 11. These image forming units 1Y, 1M, 1C, and 1K are arranged substantially linearly in the order of yellow (Y), magenta (M), cyan (C), and black (K) from the upstream side of the intermediate transfer belt 15. Has been done.

The intermediate transfer belt 15 which is an intermediate transfer body is formed so that the volume resistivity is, for example, 1 × 10 ⁶ Ωcm or more and 1 × 10 ¹⁴ Ωcm or less, and the thickness thereof is configured to be, for example, about 0.1 mm. There is.

The intermediate transfer belt 15 is circulated (rotated) by various rolls in the B direction shown in FIG. 3 at a speed suitable for the purpose. These various rolls include a drive roll 31 that is driven by a motor (not shown) having excellent constant speed to rotate the intermediate transfer belt 15, and an intermediate transfer belt 15 that extends substantially linearly along the arrangement direction of each photoconductor 11. The support roll 32 that supports the intermediate transfer belt 15, the tension applying roll 33 that exerts tension on the intermediate transfer belt 15 and functions as a correction roll that prevents the intermediate transfer belt 15 from meandering, the back roll 25 provided on the secondary transfer portion 20, and the intermediate. It has a cleaning back roll 34 provided in a cleaning portion that scrapes off residual toner on the transfer belt 15.

The primary transfer unit 10 is composed of a primary transfer roll 16 arranged so as to face the photoconductor 11 with the intermediate transfer belt 15 interposed therebetween. Then, the primary transfer roll 16 is pressure-welded to the photoconductor 11 with the intermediate transfer belt 15 interposed therebetween, and the primary transfer roll 16 has a voltage (primary) opposite to that of the toner charging polarity (minus polarity; the same applies hereinafter). Transfer bias) is applied. As a result, the toner images on the respective photoconductors 11 are sequentially electrostatically attracted to the intermediate transfer belt 15, and the superimposed toner images are formed on the intermediate transfer belt 15.

The secondary transfer unit 20 includes a back surface roll 25 and a secondary transfer roll 22 arranged on the toner image holding surface side of the intermediate transfer belt 15.

The back roll 25 is formed so that the surface resistivity is 1 × 10 ⁷ Ω / □ or more and 1 × 10 ¹⁰ Ω / □ or less, and the hardness is, for example, 70 ° (Asker C: manufactured by Polymer Instruments Co., Ltd., below. Similarly.) Is set. The back surface roll 25 is arranged on the back surface side of the intermediate transfer belt 15 to form a counter electrode of the secondary transfer roll 22, and a metal feeding roll 26 to which the secondary transfer bias is stably applied is contact-arranged. ing.

On the other hand, the secondary transfer roll 22 is a cylindrical roll having ^{a volume resistivity of 10 7.5} Ωcm or more and 10 ^{8.5 Ωcm or less.} Then, the secondary transfer roll 22 is pressure-welded to the back surface roll 25 with the intermediate transfer belt 15 interposed therebetween, and the secondary transfer roll 22 is grounded to form a secondary transfer bias with the back surface roll 25. The toner image is secondarily transferred onto the paper K conveyed to the transfer unit 20.

Further, on the downstream side of the secondary transfer portion 20 of the intermediate transfer belt 15, an intermediate transfer belt that cleans the surface of the intermediate transfer belt 15 by removing residual toner and paper dust on the intermediate transfer belt 15 after the secondary transfer. A cleaner 35 is provided so as to be detachable.

The intermediate transfer belt 15, the primary transfer unit 10 (primary transfer roll 16), and the secondary transfer unit 20 (secondary transfer roll 22) correspond to an example of the transfer means.

On the other hand, on the upstream side of the yellow image forming unit 1Y, a reference sensor (home position sensor) 42 that generates a reference signal as a reference for taking the image forming timing in each image forming unit 1Y, 1M, 1C, 1K is provided. It is arranged. Further, an image density sensor 43 for adjusting the image quality is arranged on the downstream side of the black image forming unit 1K. The reference sensor 42 recognizes a mark provided on the back side of the intermediate transfer belt 15 and generates a reference signal. According to an instruction from the control unit 40 based on the recognition of the reference signal, each image forming unit 1Y, 1M, 1C, 1K are configured to initiate image formation.

Further, in the image forming apparatus according to the present embodiment, as a transporting means for transporting the paper K, the paper accommodating unit 50 accommodating the paper K and the paper K accumulated in the paper accommodating unit 50 are taken out at a predetermined timing. The paper feed roll 51 that conveys the paper K, the transfer roll 52 that conveys the paper K fed by the paper feed roll 51, the transfer guide 53 that feeds the paper K conveyed by the transfer roll 52 to the secondary transfer unit 20, and the secondary transfer. It includes a transport belt 55 that transports the paper K that is secondarily transferred by the roll 22 to the fixing device 60, and a fixing inlet guide 56 that guides the paper K to the fixing device 60.

Next, the basic image forming process of the image forming apparatus according to the present embodiment will be described.

In the image forming apparatus according to the present embodiment, the image data output from an image reading device (not shown), a personal computer (PC) (not shown), or the like is subjected to image processing by an image processing device (not shown), and then the image forming unit 1Y. , 1M, 1C, 1K perform the image drawing work.

The image processing device performs image processing such as shading correction, position shift correction, brightness / color space conversion, gamma correction, frame erasing and color editing, and various image editing such as movement editing on the input reflectance data. Will be done. The image data that has undergone image processing is converted into color material gradation data of four colors Y, M, C, and K, and is output to the laser exposure device 13.

In the laser exposure device 13, for example, the exposure beam Bm emitted from the semiconductor laser is irradiated to each of the photoconductors 11 of the image forming units 1Y, 1M, 1C, and 1K according to the input color material gradation data. .. In each of the photoconductors 11 of the image forming units 1Y, 1M, 1C, and 1K, after the surface is charged by the charger 12, the surface is scanned and exposed by the laser exposure device 13, and an electrostatic latent image is formed. The formed electrostatic latent image is developed as a toner image of each color of Y, M, C, and K by the respective image forming units 1Y, 1M, 1C, and 1K.

The toner image formed on the photoconductors 11 of the image forming units 1Y, 1M, 1C, and 1K is transferred onto the intermediate transfer belt 15 in the primary transfer unit 10 in which each photoconductor 11 and the intermediate transfer belt 15 come into contact with each other. NS. More specifically, in the primary transfer unit 10, the primary transfer roll 16 applies a voltage (primary transfer bias) opposite to the charging polarity (minus polarity) of the toner to the base material of the intermediate transfer belt 15, and the toner image. Is sequentially superposed on the surface of the intermediate transfer belt 15 to perform the primary transfer.

After the toner image is sequentially primary-transferred to the surface of the intermediate transfer belt 15, the intermediate transfer belt 15 moves and the toner image is conveyed to the secondary transfer unit 20. When the toner image is conveyed to the secondary transfer unit 20, the transfer means rotates the paper feed roll 51 in accordance with the timing at which the toner image is conveyed to the secondary transfer unit 20, and the target is from the paper storage unit 50. Paper K of size is supplied. The paper K supplied by the paper feed roll 51 is conveyed by the transfer roll 52 and reaches the secondary transfer unit 20 via the transfer guide 53. Before reaching the secondary transfer unit 20, the paper K is temporarily stopped, and the alignment roll (not shown) rotates according to the movement timing of the intermediate transfer belt 15 on which the toner image is held, so that the paper K is formed. Is aligned with the position of the toner image.

In the secondary transfer unit 20, the secondary transfer roll 22 is pressed against the back roll 25 via the intermediate transfer belt 15. At this time, the paper K conveyed at the same timing is sandwiched between the intermediate transfer belt 15 and the secondary transfer roll 22. At that time, when a voltage (secondary transfer bias) having the same polarity as the charging polarity (minus polarity) of the toner is applied from the power feeding roll 26, a transfer electric field is formed between the secondary transfer roll 22 and the back surface roll 25. Will be done. Then, the unfixed toner image held on the intermediate transfer belt 15 is electrostatically transferred onto the paper K collectively in the secondary transfer unit 20 pressurized by the secondary transfer roll 22 and the back surface roll 25. NS.

After that, the paper K on which the toner image is electrostatically transferred is conveyed as it is in a state of being peeled off from the intermediate transfer belt 15 by the secondary transfer roll 22, and is provided on the downstream side of the secondary transfer roll 22 in the paper transfer direction. It is transported to the belt 55. The transport belt 55 transports the paper K to the fixing device 60 according to the optimum transport speed of the fixing device 60. The unfixed toner image on the paper K conveyed to the fixing device 60 is fixed on the paper K by being subjected to a fixing process by heat and pressure by the fixing device 60. Then, the paper K on which the fixed image is formed is conveyed to a paper ejection accommodating portion (not shown) provided in the ejection unit of the image forming apparatus.

On the other hand, after the transfer to the paper K is completed, the residual toner remaining on the intermediate transfer belt 15 is conveyed to the cleaning section as the intermediate transfer belt 15 rotates, and is conveyed by the cleaning back roll 34 and the intermediate transfer belt cleaner 35. It is removed from the intermediate transfer belt 15.

Although the present embodiment has been described above, the present embodiment is not limited to the above embodiment, and various modifications, changes, and improvements can be made.

For example, the same effect can be obtained in an image forming apparatus using the image forming apparatus belt according to the present embodiment as a paper transport belt.

Examples will be described below, but the present invention is not limited to these examples. In the following description, unless otherwise specified, "parts" and "%" are all based on mass.

(Preparation of raw materials)
-Preparation of coating liquid for base material-
80 parts by mass of N-methyl-2-pyrrolidone and 20 parts by mass of carbon black (SpecialBlack4, manufactured by Evonik Deguza) were stirred using a bead mill to obtain a dispersion liquid. 16 parts by mass of the obtained dispersion liquid was added to 100 parts by mass of a polyimide precursor solution (U-varnish-A, manufactured by Ube Industries, Ltd.) and mixed by stirring to obtain a coating liquid for a base material.

-Preparation of coating liquid for elastic layer-
The compounds shown below were kneaded using a twin-screw kneader.
・ Acrylic rubber (Nipol AR12, manufactured by Nippon Zeon): 100 parts ・ Steric acid (beaded stearic acid Tsubaki, Nichiyu Co., Ltd.): 1 part ・ Red phosphorus (Nova Excel 140F, manufactured by Phosphorus Chemical Industry Co., Ltd.): 10 parts ・Aluminum hydroxide (Heidilite H42M, manufactured by Showa Denko Co., Ltd.): 60 parts, hexamethylenediamine carbamate (Diak.No1, manufactured by DuPondau Elastomer Japan): 0.6 parts, cross-linking accelerator (VULCOFACACT55, 70% 1,8) − Diazabicyclo (5,4,0) salt of undecene-7 and dibasic acid, and a mixture of 30% amorphous silica, manufactured by Saffic alca): 1 part-Tetrabutylammonium perchlorate (QAP-01, Japan) (Manufactured by Carlit): 0.3 parts The obtained kneaded product was dissolved in methylisobutylketone to obtain a coating liquid for an elastic layer as a 35% solution.

-Preparation of coating liquid 1 for surface layer-
A monomer solution consisting of 286.8 parts of hydroxyethyl methacrylate, 313.2 parts of butyl methacrylate, 27 parts of a polymerization initiator (benzoyl peroxide, BPO), and 60 parts of butyl acetate was placed in a dropping funnel and subjected to nitrogen reflux. In 300 parts of butyl acetate heated to 110 ° C., the mixture was dropped over 3 hours under stirring and polymerized. Further, a liquid consisting of 135 parts of butyl acetate and 3 parts of BPO was added dropwise over 1 hour to complete the reaction. During the reaction, the temperature was always maintained at 110 ° C. and stirring was continued. In this way, the acrylic resin prepolymer A1 was synthesized.
The following liquid A and the following liquid B were mixed at the following ratios, and then the following liquid C was further added and defoamed under reduced pressure for 10 minutes to obtain a surface layer coating liquid 1.
-Liquid A (Acrylic resin prepolymer A1 solution, 44.2%, hydroxyl value 206): 113 parts-Liquid B (polyol, manufactured by Daicel Chemical Industries, Ltd., Praxel 208, polycaprolactandiol, hydroxyl value 138, [ Hydroxy groups are linked to each other by a chain having about 42 carbon atoms]): 149.6 parts-Liquid C (isocyanate, manufactured by Asahi Kasei Chemicals, Duranate TKA100, compound name: polyisocyanurate of hexamethylene diisocyanate): 138.2 parts

-Preparation of self-healing resin particles B1-
Each polymerizable monomer of n-butyl methacrylate (nBMA), hydroxyethyl methacrylate (HEMA), and an acrylic monomer having a fluorine atom and a vinyl group (FAMAC6, manufactured by Unimatec Co., Ltd.) is 2.5: 3. The mixture was mixed at a molar ratio of: 0.5. Further, a polymerization initiator (azobisisobutyronitrile (AIBN)) having a ratio of 2% by mass of the polymerizable monomer and methyl ethyl ketone (MEK) having a ratio of 40% by mass of the polymerizable monomer were added to the polymerizable simple substance. A polymer solution was prepared.
This polymerizable monomer solution was placed in a dropping funnel, and was dropped over 3 hours under stirring in MEK having a ratio of the polymerizable monomer to 50% by mass, which was heated to 80 ° C. under nitrogen reflux and polymerized. Further, a liquid composed of MEK having a ratio of 10% by mass of the polymerizable monomer and AIBN having a ratio of 0.5% by mass of the polymerizable monomer was added dropwise over 1 hour to complete the reaction. During the reaction, the temperature was maintained at 80 ° C. and stirring was continued. In this way, the acrylic resin prepolymer B1 was synthesized.
When the hydroxyl value of the obtained acrylic resin prepolymer B1 was measured according to the method (potentiometric titration method) defined in JIS K0070-1992, the hydroxyl value was 175 mgKOH / g.
Moreover, when the weight average molecular weight of the acrylic resin prepolymer B1 was measured by the above-mentioned method using gel permeation chromatography (GPC), the weight average molecular weight was 19000.
Subsequently, the following components were mixed and defoamed under reduced pressure for 10 minutes to obtain a polymerized component solution.
-Acrylic resin prepolymer B1 liquid (solid content 50% by mass): 4.4 parts-Long-chain polyol (polycaprolactone triol, Praxel 308, manufactured by Daicel Co., Ltd., molecular weight 850, hydroxyl value 190-200 mgKOH / g): 5.2 parts ・ Polyfunctional isocyanate (Duranate TPA100, manufactured by Asahi Kasei Chemicals, compound name: polyisocyanurate of hexamethylene diisocyanate): 6.4 parts ・ Cross-linking catalyst (Neostan U-600, manufactured by Nitto Kasei, compound name) : Dibutyltin): 0.08 parts ・ Methyl ethyl ketone: 12 parts

The following components were mixed and dispersed for 24 hours by a ball mill using zirconia balls to obtain a calcium carbonate dispersion.
・ Calcium carbonate (Luminous manufactured by Maruo Calcium Co., Ltd.): 36 parts ・ Anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 1.0 part ・ Salt (NaCl): 90 parts ・ Ion exchange Water: 420 copies

While operating a homogenizer (Ultratarax T50 manufactured by IKA), 100 parts of the above-mentioned polymerization component solution was added to 135 parts of the calcium carbonate dispersion to uniformly emulsify. Then, solvent removal (MEK) was carried out over 2 hours while heating at 40 ° C., and further heating was continued at 60 ° C. for 3 hours. Next, 300 parts of 1N hydrochloric acid was added to dissolve most of the calcium carbonate, and then the mixture was passed through a 40-micron nylon mesh, filtered, thoroughly washed with ion-exchanged water, and then solid-liquid separated by nutche suction filtration. bottom. Then, it was redispersed in ion-exchanged water at 40 ° C., and stirred and washed at 100 rpm using a stainless steel impeller for 15 minutes. This cleaning operation is repeated 3 times, solid-liquid separation is performed by Nucci type suction filtration, the water content is adjusted to 40%, and then dried with a flash jet dryer set to an inlet airflow temperature of 60 ° C. for self-repair. Sex resin particles B1 were obtained.
The volume average particle diameter D50v of the self-healing resin particles B1 was 15 μm, the Martens hardness was 3.5 N / mm ² , and the return rate was 86%.

-Preparation of self-healing resin particles B2-
A self-healing resin similar to the preparation of the self-healing resin particles B1 except that the amount of the acrylic resin prepolymer B1 liquid (solid content 50% by mass) added was changed to 0.4 part when preparing the polymer component solution. Particle B2 was obtained.
The volume average particle diameter D50v of the self-healing resin particles B2 was 10 μm, the Martens hardness was 0.4 N / mm ² , and the return rate was 65%.

-Preparation of self-healing resin particles B3-
Self-healing resin particles B1 except that the amount of the acrylic resin prepolymer B1 liquid (solid content 50% by mass) added was changed to 1.0 part and the long-chain polyol was changed to 8.6 parts when preparing the polymer component solution. Self-healing resin particles B3 were obtained in the same manner as in the production of.
The volume average particle diameter D50v of the self-healing resin particles B3 was 14 μm, the Martens hardness was 0.5 N / mm ² , and the return rate was 92%.

-Preparation of self-healing resin particles B4-
Self-repairing resin particles B4 were obtained in the same manner as in the preparation of self-repairing resin particles B1 except that the amount of the long-chain polyol added was changed to 0.4 part when preparing the polymer component solution.
The volume average particle diameter D50v of the self-healing resin particles B4 was 12 μm, the Martens hardness was 210 N / mm ² , and the return rate was 70%.

-Preparation of self-healing resin particles B5-
When preparing the polymerizable monomer solution, n-butyl methacrylate (nBMA) was changed to methyl methacrylate, and when preparing the polymerized component solution, the amount of long-chain polyol added was 0.4 parts, and polyfunctional isocyanate (duranate) was added. Self-repairing resin particles B5 were obtained in the same manner as in the preparation of self-repairing resin particles B1 except that TPA100) was changed to bifunctional isocyanate (Duranate D101).
The volume average particle diameter D50v of the self-healing resin particles B5 was 10 μm, the Martens hardness was 225 N / mm ² , and the return rate was 68%.

-Preparation of self-healing resin particles B6-
At the time of emulsification, the amount of calcium carbonate added was changed to 46 parts, and instead of 90 parts of salt, 1.0 part of sodium carboxymethyl cellulose (cellogen manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was changed, but the self-healing resin particles B1 Self-healing resin particles B6 were obtained in the same manner as in the production of.
The volume average particle diameter D50v of the self-healing resin particles B6 was 4 μm, the Martens hardness was 3.5 N / mm 2, and the return rate was 86%.

-Preparation of self-healing resin particles B7-
At the time of emulsification, the amount of calcium carbonate added was changed to 46 parts, and instead of 90 parts of salt, 0.5 part of sodium carboxymethyl cellulose (cellogen manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was changed, but the self-healing resin particles B1 Self-healing resin particles B7 were obtained in the same manner as in the production of.
The volume average particle diameter D50v of the self-healing resin particles B7 was 5 μm, the Martens hardness was 3.5 N / mm 2, and the return rate was 86%.

-Preparation of self-healing resin particles B8-
At the time of emulsification, the amount of calcium carbonate added was changed to 16 parts, and instead of 90 parts of salt, 1.0 part of sodium carboxymethyl cellulose (cellogen manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was changed, but the self-healing resin particles B1 Self-healing resin particles B8 were obtained in the same manner as in the production of.
The volume average particle diameter D50v of the self-healing resin particles B8 was 20 μm, the Martens hardness was 3.5 N / mm 2, and the return rate was 86%.

-Preparation of self-healing resin particles B9-
At the time of emulsification, the amount of calcium carbonate added was changed to 16 parts, and instead of 90 parts of salt, 0.5 part of sodium carboxymethyl cellulose (cellogen manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was changed, but the self-healing resin particles B1 Self-healing resin particles B9 were obtained in the same manner as in the production of.
The volume average particle diameter D50v of the self-healing resin particles B9 was 21 μm, the Martens hardness was 3.5 N / mm 2, and the return rate was 86%.

<Example 1>
(Manufacturing of belt for image forming device)
-Preparation of base material-
The cylindrical mold was brought close to the coating roller at a rotation speed of 35 mm / sec, and the coating liquid for the base material was applied to the outside of the cylindrical mold. The gap between the cylindrical mold and the coating roller was set to 0.4 mm. While maintaining the rotation of the cylindrical mold, the cylindrical mold was put into a hot air circulation dryer, the temperature was raised to 110 ° C., and then heating was performed for 30 minutes. Subsequently, the temperature was raised to 200 ° C., and then heating was performed for 30 minutes. The rotation of the cylindrical mold was stopped, the cylindrical mold was transferred to a firing furnace, the temperature was raised to 320 ° C., and then heating was performed for 60 minutes to obtain a substrate having a thickness of 80 μm on the cylindrical mold.
-Preparation of elastic layer and surface layer containing self-healing resin particles-
While rotating the cylindrical mold on which the base material was formed, the coating liquid for the elastic layer was discharged from the nozzle, and the coating liquid for the elastic layer was spirally applied onto the base material. The coating amount was set so that the film thickness of the elastic layer was 75 μm.
Self-healing resin particles B1 are added to the surface layer coating liquid 1 so as to be 35% of the total solution, and methyl ethyl ketone is added so that the total solid content concentration in the solution is 80%. After that, the self-healing resin particles were dispersed. The surface layer coating liquid 1 in which the self-healing resin particles B1 were dispersed was applied to the surface of the layer formed by applying the elastic layer coating liquid using anix roll and heated at 120 ° C. After the surface layer coating liquid 1 in which the self-healing resin particles B1 are dispersed is applied to the entire surface of the layer formed by applying the elastic layer coating liquid, the coating with the anix roll is stopped and hot air circulation drying is performed. A cylindrical mold was put into the machine, the temperature was raised to 120 ° C., and then heating was performed for 60 minutes. The obtained image forming apparatus belt was removed from the cylindrical mold to obtain an image forming apparatus belt 1. The thickness of the elastic layer of the obtained belt 1 for an image forming apparatus was 75 μm, and the film thickness of the surface layer was 8 μm.

<Example 2>
By the same procedure as in Example 1, a base material was formed on the cylindrical mold with the base material coating liquid, and then the elastic layer coating liquid was applied onto the base material. The coating amount was set so that the final film thickness would be 75 μm. When the coating film has spread evenly after the predetermined total amount has been poured, the particle arrangement is regulated by anilox rolls to attach the self-healing resin particles B1 to the coating film surface, and then the pressing member of the polyurethane rubber blade is pressed against the particles. And embedded in the elastic layer. At this time, the pressing force of the pressing member was set to 100 mN / cm. A cylindrical mold in which self-healing resin particles B1 are embedded on a layer formed by applying a coating liquid for an elastic layer is put into a coating hot air circulation dryer, heated to 120 ° C., and then heated for 60 minutes. went. The obtained image forming apparatus belt was removed from the cylindrical mold to obtain an image forming apparatus belt 2. The film thickness of the elastic layer of the obtained image forming apparatus belt 2 was 75 μm.

<Example 3>
The surface layer coating liquid 1 contains DM-A6000 (manufactured by Daizo Co., Ltd., PTFE-containing urethane resin) and DM-A6000XL (manufactured by Daizo Co., Ltd., glycidoxypropyltrimethoxysilane curing agent) in a mass ratio of 95: 5. An image forming apparatus belt 3 was obtained in the same manner as in Example 1 except that the mixed solution was mixed in a ratio and the film thickness of the surface layer was changed as shown in Table 1.

<Example 4>
The surface layer coating liquid 1 was changed to B-19034X (manufactured by Osaka Soda Co., Ltd., silicone acrylic resin), and the film thickness of the surface layer was changed as shown in Table 1 in the same manner as in Example 1. An image forming apparatus belt 4 was obtained.

<Example 5>
Self-healing resin particles B1 and other particles such as silica particles (Sunsphere H51, manufactured by AGC, volume average particle size 5 μm) were used as the particles dispersed in B-19034X, and the thickness of the surface layer was shown in Table 1. An image forming apparatus belt 5 was obtained in the same manner as in Example 4 except that the changes were made as described.
The silica particles used were 15% by mass with respect to the self-healing resin particles B1.

<Example 6>
Self-healing resin particles B1 and other particles, nylon resin particles (SP-10, manufactured by Toray Industries, Inc., volume average particle size 10 μm) are used as the particles to be dispersed in B-19034X, and the thickness of the surface layer is shown. An image forming apparatus belt 6 was obtained in the same manner as in Example 4 except that the changes were made as described in 1.
The nylon resin particles were used in an amount of 10% by mass based on the self-healing resin particles B1.

<Example 7>
An image forming apparatus belt 7 was obtained in the same manner as in Example 1 except that the self-healing resin particles B6 were added to the surface layer coating liquid 1 instead of the self-healing resin particles B1.

<Example 8>
An image forming apparatus belt 8 was obtained in the same manner as in Example 1 except that the self-healing resin particles B7 were added to the surface layer coating liquid 1 instead of the self-healing resin particles B1.

<Example 9>
An image forming apparatus belt 9 was obtained in the same manner as in Example 1 except that the self-healing resin particles B8 were added to the surface layer coating liquid 1 instead of the self-healing resin particles B1.

<Example 10>
An image forming apparatus belt 10 was obtained in the same manner as in Example 1 except that the self-healing resin particles B9 were added to the surface layer coating liquid 1 instead of the self-healing resin particles B1.

<Example 11>
Acrylic resin prepolymer B1 liquid (solid content 50% by mass) at the time of producing the resin particles B1 in Example 1: Image forming apparatus in the same manner as in Example 1 except that 4.4 parts was changed to 0.4 parts. A belt 11 was obtained.

<Example 12>
4.4 parts of the acrylic resin prepolymer B1 liquid (solid content 50% by mass) at the time of producing the resin particles B1 in Example 1 was changed to 1.0 part, and 5.2 parts of the long-chain polyol was changed to 8.6 parts. A belt 12 for an image forming apparatus was obtained in the same manner as in Example 1 except for the above.

<Example 13>
A belt 13 for an image forming apparatus was obtained in the same manner as in Example 1 except that 5.2 parts of the long chain polyol at the time of producing the resin particles B1 in Example 1 was changed to 0.4 parts.

<Example 14>
Long-chain polyol 5.2 during the production of the resin particles B1 by changing n-butyl methacrylate (nBMA) during the synthesis of the acrylic resin prepolymer B1 and the synthesis of the acrylic resin prepolymer B1 in Example 1 to methyl methacrylate. The image forming apparatus belt 14 is the same as in Example 1 except that the part is changed to 0.4 part and the polyfunctional isocyanate (Duranate TPA100) used for producing the resin particles B1 is changed to the bifunctional isocyanate (Duranate D101). Got

<Example 15>
The self-healing resin particles B1 are added to the surface layer coating liquid 1 in Example 1 in the range of 25% to 35% with respect to the entire solution, the self-healing resin particles are dispersed, and the self-healing resin particles are exposed from the surface. An image forming apparatus belt 15 was obtained in the same manner as in Example 1 except that the abundance ratio of the self-healing resin particles ^{was controlled to 390 particles / mm 2.}

<Example 16>
The self-healing resin particles B1 are added to the surface layer coating liquid 1 in Example 1 in the range of 25% to 35% with respect to the entire solution, the self-healing resin particles are dispersed, and the self-healing resin particles are exposed from the surface. An image forming apparatus belt 16 was obtained in the same manner as in Example 1 except that the abundance ratio of the self-healing resin particles ^{was controlled to 420 particles / mm 2.}

<Example 17>
The self-healing resin particles B1 are added to the surface layer coating liquid 1 in Example 1 in the range of 35% to 45% with respect to the entire solution, the self-healing resin particles are dispersed, and the self-healing resin particles are exposed from the surface. An image forming apparatus belt 17 was obtained in the same manner as in Example 1 except that the abundance ratio of the self-healing resin particles ^{was controlled to 39000 particles / mm 2.}

<Example 18>
The self-healing resin particles B1 are added to the surface layer coating liquid 1 in Example 1 in the range of 35% to 45% with respect to the entire solution, the self-healing resin particles are dispersed, and the self-healing resin particles are exposed from the surface. An image forming apparatus belt 18 was obtained in the same manner as in Example 1 except that the abundance ratio of the self-healing resin particles ^{was controlled to 41,000 particles / mm 2.}

<Example 19>
The belt for the image forming apparatus in the same manner as in Example 1 except that the number of lines of the anilox roll in Example 1 was changed from 55 lines / inch to 2400 lines / inch and the thickness of the surface layer was controlled to 0.9 μm. I got 19.

<Example 20>
Similarly, an image forming apparatus belt 20 was obtained in the same manner as in Example 1 except that the thickness of the surface layer was controlled to 1.0 μm.

<Example 21>
Similarly, an image forming apparatus belt 21 was obtained in the same manner as in Example 1 except that the thickness of the surface layer was controlled to 20.0 μm.

<Example 22>
Similarly, an image forming apparatus belt 22 was obtained in the same manner as in Example 1 except that the thickness of the surface layer was controlled to 21.0 μm.

<Example 23>
Except that the amount of the self-healing resin particles B1 added in Example 1 was changed from 5% to 50% with respect to the entire solution, and the surface roughness Ra and the film thickness of the surface layer were controlled as shown in Table 2. An image forming apparatus belt 23 was obtained in the same manner as in Example 1.

<Example 24>
Similarly, an image forming apparatus belt 24 was obtained in the same manner as in Example 1 except that the surface roughness Ra and the film thickness of the surface layer were controlled as shown in Table 2.

<Example 25>
Similarly, an image forming apparatus belt 25 was obtained in the same manner as in Example 1 except that the surface roughness Ra and the film thickness of the surface layer were controlled as shown in Table 2.

<Example 26>
Similarly, an image forming apparatus belt 26 was obtained in the same manner as in Example 1 except that the surface roughness Ra and the film thickness of the surface layer were controlled as shown in Table 2.

<Comparative example 1>
An image forming apparatus belt C1 was obtained in the same manner as in Example 3 except that the self-healing resin particles B1 were not used and the film thickness was controlled as shown in Table 2.

<Comparative example 2>
An image forming apparatus belt C2 was obtained in the same manner as in Example 4 except that the self-healing resin particles B1 were not used and the film thickness was controlled as shown in Table 2.

<Comparative example 3>
An image forming apparatus belt C3 was obtained in the same manner as in Example 8 except that benzoguanamine resin particles (manufactured by Nippon Shokubai Co., Ltd .: Epostal M05, average particle size 5 μm) were used instead of the self-healing resin particles B7. ..

<Image quality evaluation>
The image forming apparatus belt obtained in each example was attached as an intermediate transfer belt as a transfer transfer belt for the transfer portion of the image forming apparatus "Fuji Xerox D110 (monochrome multifunction device)", and the Rezac 66 (unevenness paper) 50 After continuously outputting images to 10,000 images, image quality evaluation was performed on a blue image composed of cyan and magenta having an image density of 100%.
Here, the image quality was evaluated according to the following criteria.
A (◎): No decrease in image density B (○): Image density decreases slightly (within acceptable level)
C (Δ): Image density decreases (unacceptable level)
D (x): Image density is significantly reduced (greatly exceeds the permissible level)

<Abrasion resistance evaluation>
The belt for the image forming apparatus obtained in each example was used as an intermediate transfer belt and mounted as a transfer transfer belt for the transfer portion of the image forming apparatus "D110 (monochrome multifunction device) manufactured by Fuji Xerox Co., Ltd." Paper) After passing 2.5 million sheets of paper, the wear state of the intermediate transfer belt was visually evaluated.
Here, the wear resistance was evaluated according to the following criteria.
A (◎): Almost no change from the initial stage B (○): Slight wear but practical level C (△): Scratches or surface peeling but practical level D (×): Wear Is a large and impractical level

Hereinafter, the descriptions in Tables 1 and 2 will be described.
“Surface roughness” represents a measured value of the surface roughness of the belt for an image forming apparatus created in Examples and Comparative Examples.
"Coating liquid" represents the type of coating liquid for the surface layer used in Examples and Comparative Examples, and "resin type" is the main component of the resin component constituting the surface layer (mass of the resin constituting the surface layer). The component with the highest ratio content).
For "other particles", when the image forming apparatus belt created in Examples and Comparative Examples contains particles other than self-healing resin particles, the type of other particles is described in "Particle type". , Enter the particle size of the other particles in the "particle size (listed in the column of other particles)" column.
"-" Indicates that the surface layer or other particles are not present, or the thickness of the surface layer or the particle size of the other particles is not measured.
“Si particles” represent silica particles, and “Ny particles” represent nylon particles.

From the above results, it can be seen that the image forming apparatus belt of this embodiment can suppress image omission due to continuous use.

1Y, 1M, 1C, 1K Image forming unit 10 Primary transfer unit 11 Photoreceptor 12 Charger 13 Laser exposure device 14 Developer 15 Intermediate transfer belt 16 Primary transfer roll 17 Photoreceptor cleaner 20 Secondary transfer unit 22 Secondary transfer roll 25 Back roll 26 Power supply roll 31 Drive roll 32 Support roll 33 Tension application roll 34 Cleaning Back roll 35 Intermediate transfer belt cleaner 40 Control unit 42 Reference sensor 43 Image density sensor 50 Paper storage unit 51 Paper feed roll 52 Transport roll 53 Transport guide 55 Transport Belt 56 Fixing inlet guide 60 Fixing device 100 Image forming device 70 Base material 72 Elastic layer 74 Surface layer 76 Self-healing resin particles

Claims (11)

With the base material
An elastic layer provided on the base material and
With self-healing resin particles,
When the surface layer is provided on the elastic layer, the self-repairing resin particles are contained in the surface layer in a state where the self-repairing resin particles are exposed from the surface of the surface layer.
When the elastic layer does not have a surface layer, the image forming apparatus belt contains the self-repairing resin particles in the elastic layer in a state where the self-repairing resin particles are exposed from the surface of the elastic layer. The belt for an image forming apparatus according to claim 1, wherein the volume average particle diameter D50v of the self-healing resin particles is 5 μm or more and 20 μm or less. The belt for an image forming apparatus according to claim 1 or 2, wherein the self-healing resin particles are particles containing an acrylic urethane resin. The third aspect of claim 3, wherein the particles containing the acrylic urethane resin have a Martens hardness of 0.5 N / mm ² or more and 220 N / mm ² or less at 23 ° C. and a return rate of 70% or more and 100% or less at 23 ° C. Belt for image forming equipment. The acrylic urethane resin includes a hydroxyl group-containing acrylic resin (a), a polyol (b) having a plurality of hydroxyl groups and having the hydroxyl groups via a carbon chain having 6 or more carbon atoms, and a polyfunctional isocyanate (c). The image forming apparatus belt according to claim 3 or 4, which is a reaction product of. The proportion of the self-healing resin particles exposed from the surface of the surface layer or the elastic layer, any one of 400 / mm ² or more 40000 / mm ² or less is claims 1 to 5 The belt for the image forming apparatus described. The belt for an image forming apparatus according to any one of claims 1 to 6, wherein the thickness of the surface layer is 1.0 μm or more and 20.0 μm or less. The belt for an image forming apparatus according to any one of claims 1 to 7, wherein the surface roughness Ra of the surface layer or the elastic layer is 0.1 μm or more and 10.0 μm or less. The belt for an image forming apparatus according to any one of claims 1 to 8, wherein the surface layer contains an acrylic urethane resin. The acrylic urethane resin includes a hydroxyl group-containing acrylic resin (a), a polyol (b) having a plurality of hydroxyl groups and having the hydroxyl groups via a carbon chain having 6 or more carbon atoms, and a polyfunctional isocyanate (c). The image forming apparatus belt according to claim 9, which is a reaction product of. An image forming apparatus including the image forming apparatus belt according to any one of claims 1 to 10.

Images