JP7400239B2 - Image forming method - Google Patents

Description

The present invention relates to an image forming method and an image forming apparatus.

In recent years, demand for special color printing, metallic printing, and high value-added printing has been increasing in the on-demand printing market. Among these, demands regarding metallic printing and pearl printing are particularly large, and a wide variety of studies are being conducted. Further, although the recording medium for the above-mentioned printing is mainly paper media, there is an increasing demand for printing on non-paper media such as film.

For example, in Patent Document 1, a toner image is formed, a foil body having a colorant layer and an adhesive layer is superimposed on the toner image, heated and pressurized, and the toner is welded by heating. Discloses a method for decorating images. It is stated that this allows foil attachment and transfer without causing wrinkles on the foil body.

Further, Patent Document 2 discloses a method of forming a metallic image by using a glitter toner containing a glitter pigment only in necessary areas. It is stated that by using a glitter toner, an image with high glitter can be formed even when the amount of applied toner is low.

Japanese Patent Application Publication No. 01-200985 Japanese Patent Application Publication No. 2014-157249

In Patent Document 1, a desired image is obtained by using a transfer foil, and in Patent Document 2, a desired image is obtained by using a glitter toner. However, according to studies conducted by the present inventors, the desired gloss could not be obtained in both cases.

The present invention has been made in view of the above, and an object of the present invention is to provide an image forming method and an image forming apparatus that can easily produce images having sufficient gloss and metallic appearance.

The image forming method of the present invention is an image forming method for forming a decorated image by decorating a resin image including a recording medium and a thermoplastic resin layer formed on the recording medium, a powder orientation step of orienting the powder held on the powder holding surface; a powder transfer step of transferring the oriented powder to the surface of the thermoplastic resin layer; In measuring the viscoelasticity of the resin layer, the storage modulus G' at 90°C when measured from 30°C to 100°C under the measurement conditions of a frequency of 1 Hz and a heating rate of 3°C/min is 1.0 × 10 ³ Pa or more. It is 1.0×10 ⁷ Pa or less.

The image forming apparatus of the present invention includes a powder holding member having a powder holding surface for holding powder, an orientation member for orienting the powder held on the powder holding surface, and a powder holding member for orienting the powder held on the powder holding surface. A recording medium having a thermoplastic resin layer is provided at a position facing the powder holding surface of the body holding member, and a recording medium having a thermoplastic resin layer is sandwiched between the powder holding surface and the powder is applied to the surface of the thermoplastic resin layer. and a facing member for transferring.

According to the present invention, it is possible to provide an image forming method and an image forming apparatus that can easily produce an image having sufficient gloss and metallic appearance.

FIG. 1 is a diagram schematically showing the configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing the configuration of a surface treatment section that is a part of the image forming apparatus according to an embodiment of the present invention.

Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments.

1. Image Forming Method An image forming method according to an embodiment of the present invention is for forming a decorated image by decorating a resin image including a recording medium and a thermoplastic resin layer formed on the recording medium. An image forming method comprising: (1) a powder orientation step of orienting the powder held on a powder holding surface; and (2) a powder orientation step of transferring the oriented powder to the surface of a thermoplastic resin layer. and an image forming method. Furthermore, the image forming method according to an embodiment of the present invention may include a resin layer forming step and a powder supplying step before the steps (1) and (2) above. Each step will be explained below.

1-1. Resin Layer Forming Step The resin layer forming step involves applying a thermoplastic resin onto the recording medium using a known image forming method such as a dry or wet electrophotographic method or an inkjet method to form a thermoplastic resin layer (hereinafter referred to as This is the process of forming a resin layer (also referred to as a "resin layer").

1-1-1. Recording Medium The recording medium that can be used in the present invention is not particularly limited as long as a resin layer can be formed thereon. Examples of recording media include plain paper from thin to thick paper, high-quality paper, coated printing paper such as art paper or coated paper, commercially available Japanese paper or postcard paper, plastic film, resin film, cloth, etc. Includes various types of Further, the shape and color of the recording medium are not particularly limited, and can be appropriately selected depending on the final image to be formed.

1-1-2. Thermoplastic Resin Layer The thermoplastic resin layer is a resin layer containing a thermoplastic resin. The thermoplastic resin layer is preferably a layer made of a toner image formed by an electrophotographic method, and more preferably a resin layer made of toner particles fixed to the recording medium described above. In addition, the resin layer has a storage elastic modulus G' of 1.0×10 3 Pa or more at 90° C. when measured from 30° C. to 100° C. under measurement conditions of a frequency of 1 Hz and a temperature increase rate of ³ ° C./min. .0×10 ⁷ Pa or less, and more preferably 1.0×10 ⁴ Pa or more and 5.0×10 ⁶ Pa or less. Note that the "storage modulus" is an index of the hardness of a material, and the smaller the value, the softer the material is. Note that the storage modulus G' can be measured using a rheometer "ARESG2" (manufactured by TA INSTRUMENT).

When the storage modulus G' at 90° C. is 1.0×10 ³ Pa or more, the softened resin layer has appropriate hardness and prevents the resin layer from collapsing, so the color of the resin layer changes. It is possible to make density differences less likely to occur and to make the underlying recording medium less visible. In addition, if the storage modulus G' at 90°C is 1.0 x 10 ⁷ Pa or less, the resin layer will become moderately soft by heating, and the resin will easily penetrate into the unevenness of the powder surface. Since the contact area between the resin constituting the resin layer and the powder increases, the adhesion of the powder to the resin layer can be improved. Thereby, an image having desired glossiness and metallic feel (mirror tone/pearl tone) can be easily produced.

Further, the thermoplastic resin constituting the resin layer can be appropriately selected from known thermoplastic resins. Note that the resin layer may contain other components such as a colorant, a dispersant, a surfactant, a plasticizer, a mold release agent, and an antioxidant.

Examples of thermoplastic resins include styrene resins, (meth)acrylic resins, styrene-(meth)acrylic copolymer resins, vinyl resins such as olefin resins, polyester resins, crystalline polyester resins, and amorphous resins. These include polyester resins, polyamide resins, carbonate resins, polyethers, and polyvinyl acetate resins. Among the above thermoplastic resins, styrene resins, acrylic resins, styrene-(meth)acrylic copolymer resins, and polyester resins are preferred, and styrene-(meth)acrylic copolymer resins are preferable. is more preferable. The thermoplastic resin is not particularly limited as long as the storage modulus G' of the resin layer at 90° C. is 1.0×10 ³ Pa or more and 1.0×10 ⁷ Pa or less. In addition, the above-mentioned thermoplastic resins may be used alone or in combination of two or more types.

"Styrene-(meth)acrylic copolymer resin" as used in the present invention refers to a copolymer resin formed by polymerizing at least a styrene monomer and a (meth)acrylic acid ester monomer. Refers to polymer resin. Note that the styrene monomer includes not only styrene represented by the structural formula of CH ₂ =CH-C ₆ H ₅ but also those having a structure having a known side chain or functional group in the styrene structure.

Furthermore, the term "(meth)acrylic acid ester monomer" as used in the present invention refers to a monomer having a functional group having an ester bond in its side chain. Examples of (meth)acrylic ester monomers include acrylic ester monomers represented by CH ₂ =CHCOOR (R is an alkyl group), and CH ₂ =C(CH ₃ )COOR (R is an alkyl group). It includes vinyl ester compounds such as methacrylic acid ester monomers represented by (group).

Examples of the above-mentioned styrene-(meth)acrylic copolymer resins include copolymers formed only from the above-mentioned styrene monomers and (meth)acrylic acid ester monomers, as well as general vinyl monomers. It also includes copolymers formed by further using olefins, vinyl esters, vinyl ethers, vinyl ketones, N-vinyl compounds, etc. Furthermore, examples of styrene-(meth)acrylic copolymer resins include styrene monomers, (meth)acrylic acid ester monomers, and other general vinyl monomers, as well as polyfunctional vinyl monomers. It also includes copolymers formed using vinyl monomers having an ionic dissociative group (carboxyl group, sulfonic acid group, phosphoric acid group, etc.) in the side chain. Examples of vinyl monomers include acrylic acid, methacrylic acid, maleic acid, itaconic acid, and the like.

Moreover, a copolymer may be sufficient as the thermoplastic resin mentioned above. When the thermoplastic resin is a copolymer, the form of the copolymer may be a block copolymer, a random copolymer, a graft copolymer, or an alternating copolymer.

Moreover, it is preferable that the thermoplastic resin layer contains a crystalline resin.

The crystalline resin contained in the resin layer is preferably a crystalline polyester resin. By including a crystalline polyester resin in the resin layer, it is possible to reduce the gradient of change in the storage modulus G' of the resin layer around 90°C. Therefore, the heating temperature for softening the resin layer can be adjusted over a wide range (e.g. 70-100°C). This makes it easier to adjust the resin layer to the desired softness even if the heating temperature varies, making it easier to create images with the desired gloss and metallic feel (mirror tone/pearl tone). I can do it.

A crystalline polyester resin is a crystalline resin obtained by a polycondensation reaction between a divalent or higher carboxylic acid (polyvalent carboxylic acid compound) and a divalent or higher alcohol (polyhydric alcohol compound).

The polyvalent carboxylic acid compound is a compound having two or more carboxy groups in one molecule, and alkyl esters, acid anhydrides, and acid chlorides of polyvalent carboxylic acid compounds can be used.

Examples of the polyvalent carboxylic acid compounds include oxalic acid, succinic acid, malonic acid, adipic acid, β-methyladipic acid, pimelic acid, azelaic acid, sebacic acid, nonanedicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, 2 such as dodecanedicarboxylic acid, maleic acid, fumaric acid, citraconic acid, diglycolic acid, cyclohexane-3,5-diene-1,2-dicarboxylic acid, malic acid, citric acid, hexahydroterephthalic acid, tartaric acid, mucinic acid, etc. aliphatic carboxylic acids; phthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-carboxyphenylacetic acid, p-phenylenediacetic acid, m-phenylene diglycolic acid, p-phenylene diacetic acid Glycolic acid, o-phenylene diglycolic acid, diphenyl-p,p'-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, anthracene dicarboxylic acid and divalent aromatic carboxylic acids such as dodecenylsuccinic acid; trivalent or higher aromatic carboxylic acids such as trimellitic acid, pyromellitic acid, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, pyrenetricarboxylic acid, and pyrenetetracarboxylic acid. included.

From the viewpoint of improving the crystallinity of the crystalline polyester resin, divalent aliphatic carboxylic acids are preferred among the polyvalent carboxylic acid compounds. In addition, the said polyhydric carboxylic acid compound may use only one type independently, and may use two or more types together.

A polyhydric alcohol compound is a compound having two or more hydroxy groups in one molecule.

Examples of the polyhydric alcohol compounds include divalent linear aliphatic alcohols such as ethylene glycol, propylene glycol, butanediol, diethylene glycol, hexanediol, octanediol, decanediol, and dodecanediol; divalent linear aliphatic alcohols such as cyclohexanediol; Alicyclic alcohols; divalent aromatic alcohols such as ethylene oxide adducts of bisphenol A and propylene oxide adducts of bisphenol A; trihydric or higher aliphatic alcohols such as glycerin and pentaerythritol; hexamethylolmelamine, tetramethylolbenzoguanamine , alcohols having a trivalent or higher guanidine skeleton, such as tetraethylolbenzoguanamine.

From the viewpoint of increasing the crystallinity of the crystalline polyester resin, among the polyhydric alcohol compounds, divalent aliphatic alcohols are preferred, and divalent linear aliphatic alcohols are more preferred. In addition, the said polyhydric alcohol compound may use only one type independently and may use two or more types together.

The ratio of the polyhydric alcohol compound and the polycarboxylic acid compound in the monomer for synthesizing the crystalline polyester resin is the ratio of the hydroxy group [OH] of the polyhydric alcohol compound to the carboxy group [COOH] of the polyhydric carboxylic acid compound. The equivalent ratio [OH]/[COOH] is preferably 2.0/1.0 to 1.0/2.0, and 1.5/1.0 to 1.0/1.5. It is more preferable.

The crystalline polyester resin preferably has a clear endothermic peak rather than a step-like endothermic change in differential scanning calorimetry (DSC). Here, the term "clear endothermic peak" refers to a peak whose half-value width is within 15°C when measured at a heating rate of 10°C/min in differential scanning calorimetry (DSC). .

Furthermore, the term "crystalline polyester resin" refers to not only a polymer whose constituent components are 100% polyester structure, but also a polymer (copolymer) formed by copolymerizing a component constituting polyester with another component. However, in the latter case, the amount of other constituent components other than polyester constituting the polymer (copolymer) is 50.0% by mass or less.

Further, a monocarboxylic acid and/or a monoalcohol is further added to the polyester resin obtained by polycondensation of a polyhydric carboxylic acid and a polyhydric alcohol to esterify the hydroxyl group and/or carboxyl group at the polymerization terminal, The acid value of the polyester resin may be adjusted. Examples of monocarboxylic acids include acetic acid, acetic anhydride, benzoic acid, trichloroacetic acid, trifluoroacetic acid, propionic anhydride, and the like. Furthermore, examples of monoalcohols include methanol, ethanol, propanol, octanol, 2-ethylhexanol, trifluoroethanol, trichloroethanol, hexafluoroisopropanol, phenol, and the like.

The weight average molecular weight (Mw) of the thermoplastic resin constituting the resin layer is not particularly limited, but is preferably from 2,000 to 1,000,000, more preferably from 5,000 to 100,000. A range of 10,000 to 50,000 is particularly preferred.

The weight average molecular weight (Mw) of the thermoplastic resin constituting the resin layer is determined by the equipment "HLC-8320GPC" (manufactured by Tosoh Corporation), one column "TSKguardcolumn" and three "TSKgelSuperHZ-M" (both manufactured by Tosoh Corporation). It can be measured using a combination of

Tetrahydrofuran (THF) is flowed as a carrier solvent at a flow rate of 0.2 mL/min while maintaining the column temperature at 40°C. The measurement sample (resin) was dissolved in tetrahydrofuran to a concentration of 1 mg/mL, treated with an ultrasonic disperser at room temperature for 5 minutes, and processed with a membrane filter with a pore size of 0.2 μm to obtain a sample solution. get. 10 μL of this sample solution is injected into the apparatus together with the above carrier solvent, and detected using a refractive index detector (RI detector). The molecular weight distribution of the measurement sample is calculated based on a calibration curve created using monodisperse polystyrene standard particles. The calibration curve is manufactured by Tosoh Corporation "polystylene standard sample TSK standard": "A-500", "F-1", "F-10", "F-80", "F-380", "A-2500" , "F-4", "F-40", "F-128", and "F-700". Note that the data collection interval in sample analysis is 300 ms.

In addition, the content of thermoplastic resin in the resin layer is not particularly limited, but from the viewpoint of softening the surface of the resin layer by heat and making it easier to control the surface condition of the resin layer, it is necessary to It is preferably 60.0 to 97.0% by mass, more preferably 70.0 to 95.0% by mass.

On the other hand, when the resin layer contains other components other than the thermoplastic resin (for example, a coloring agent, a mold release agent, etc.), the content of the other components is not particularly limited, but the surface of the resin layer is softened by heat, From the viewpoint of making it easier to control the surface state of the resin layer, it is preferably 3.0 to 40.0% by mass, and preferably 5.0 to 30.0% by mass, based on the total mass of the resin layer. More preferred.

The resin layer described above is a layer composed of a toner image formed by an electrophotographic method, and is preferably a layer composed of a plurality of types of toners fixed on a recording medium. By configuring the resin layer with multiple types of toner, various decorative images can be formed by combining toner images and powder. The plurality of types of toners described above may include, for example, a plurality of types of toner particles that exhibit different colors depending on the coloring materials they contain. Examples of toner particles include black toner particles, white toner particles, clear toner particles, cyan toner particles, yellow toner particles, magenta toner particles, and the like.

Toner particles can be manufactured by adding and mixing external additives to toner base particles. Examples of methods for producing toner base particles include a pulverization method, an emulsion polymerization aggregation method, a suspension polymerization method, a dissolution suspension method, an emulsion aggregation method, and the like. Among these, the emulsion aggregation method and the emulsion polymerization aggregation method are preferred as the method for producing toner base particles.

In particular, the toner base particles of the present invention are prepared by mixing a dispersion liquid in which colorant fine particles are dispersed in an aqueous medium and a dispersion liquid in which resin fine particles are dispersed in an aqueous medium, and then the colorant fine particles and the resin are mixed. It is preferable that the material be obtained by a process of agglomerating and fusing fine particles, that is, by a manufacturing method such as an emulsion aggregation method. The reason why such a manufacturing method is preferable is that the colorant fine particles have excellent dispersibility in the colorant dispersion liquid contained in the toner base particles, and furthermore, when the colorant fine particles and the resin fine particles are aggregated and fused, This is also because toner base particles can be formed while the fine colorant particles maintain excellent dispersibility.

It is preferable that the toner base particles contain, for example, the above-mentioned resin, and also contain a colorant and a release agent. Further, the toner base particles may contain a charge control agent and a magnetic material. The colorant, mold release agent, external additive, charge control agent, and magnetic material will be explained below.

As the colorant, known colorants can be used. Specifically, as a yellow colorant for yellow toner, C.I. I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162, and C.I. I. Pigment Yellow 14, Pigment Yellow 17, Pigment Yellow 74, Pigment Yellow 93, Pigment Yellow 94, Pigment Yellow 138, Pigment Yellow 155, Pigment Yellow 180, Pigment Yellow 185, etc. can be used, and mixtures thereof can also be used.

As a magenta colorant for magenta toner, C.I. I. Solvent Red 1, Solvent Red 49, Solvent Red 52, Solvent Red 58, Solvent Red 63, Solvent Red 111, Solvent Red 122, etc., and C.I. I. Pigment Red 5, 48:1, 53:1, 57:1, 122, 139, 144, 149, 166, 177, 178, 222, etc. can be used, and these Mixtures of can also be used.

As a cyan coloring agent for cyan toner, C.I. I. Solvent Blue 25, Solvent Blue 36, Solvent Blue 60, Solvent Blue 70, Solvent Blue 93, Solvent Blue 95, etc., and C.I. I. Pigment Blue 1, Pigment Blue 7, Pigment Blue 15:3, Pigment Blue 18:3, Pigment Blue 60, Pigment Blue 62, Pigment Blue 66, Pigment Blue 76, etc. can be used.

As an orange coloring agent for orange toner, C.I. I. Solvent Orange 63, Solvent Orange 68, Solvent Orange 71, Solvent Orange 72, Solvent Orange 78, etc., and C.I. I. Pigment Orange 16, 36, 43, 51, 55, 59, 61, 71, etc. can be used.

As a green coloring agent for green, C.I. I. Solvent Green 3, Solvent Green 5, Solvent Green 28, etc., and C.I. I. Pigment Green 7 etc. can be used.

As colorants for black toner, carbon black, magnetic materials, iron/titanium composite oxide black, etc. can be used. Examples of carbon black include channel black, furnace black, acetylene black, thermal black, lamp black, etc. Available for use. Further, as the magnetic material, ferrite, magnetite, etc. can be used.

Colorants for white toner include inorganic pigments (e.g., titanium white, zinc white, titanium strontium white, heavy calcium carbonate, light calcium carbonate, titanium dioxide, aluminum hydroxide, satin white, talc, calcium sulfate, barium sulfate). , zinc oxide, magnesium oxide, magnesium carbonate, amorphous silica, colloidal silica, white carbon, kaolin, calcined kaolin, delaminated kaolin, aluminosilicate, sericite, bentonite, smexite, etc.), or organic pigments (e.g. polystyrene resin particles, urea formalin resin particles, etc.) can be used.

The content of the colorant is preferably 1.0 to 10.0 parts by weight, more preferably 2.0 to 9.0 parts by weight, based on 100.0 parts by weight of the resin.

Further, the mold release agent that can be included in the toner base particles is not particularly limited, and any known mold release agent can be used. Examples of mold release agents include polyolefin waxes such as polyethylene wax and polypropylene wax; branched chain hydrocarbon waxes such as microcrystalline wax; long chain hydrocarbon waxes such as paraffin wax and Sasol wax; distearyl ketone, etc. Dialkyl ketone wax; carnauba wax, montan wax, behenyl behenate, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1, 18 - Ester waxes such as octadecanediol distearate, tristearyl trimellitate, and distearyl maleate; amide waxes such as ethylenediamine behenylamide and tristearyl trimellitate; and the like. These may be used alone or in combination of two or more.

The content of the mold release agent is preferably 1.0 to 30.0 parts by weight, more preferably 2.0 to 20.0 parts by weight, based on 100.0 parts by weight of the resin.

As the external additive, known metal oxide particles can be used for the purpose of controlling fluidity and chargeability. Examples of external additives include silica particles, titania particles, alumina particles, zirconia particles, zinc oxide particles, chromium oxide particles, cerium oxide particles, antimony oxide particles, tungsten oxide particles, tin oxide particles, tellurium oxide particles, and manganese oxide particles. particles, and boron oxide particles. These may be used alone or in combination of two or more.

Furthermore, organic fine particles such as homopolymers of styrene, methyl methacrylate, and copolymers thereof may be used as external additives.

A lubricant may be used as an external additive to further improve cleaning properties and transfer properties. Examples of lubricants include stearic acid salts of zinc, aluminum, copper, magnesium, calcium, etc., oleic acid salts of zinc, manganese, iron, copper, magnesium, etc., and palmitic acid salts of zinc, copper, magnesium, calcium, etc. Metal salts of higher fatty acids such as salts of linoleic acid such as zinc and calcium salts and salts of ricinoleic acid such as zinc and calcium are included.

The amount of these external additives added is preferably 0.1 to 10.0% by mass, more preferably 1.0 to 5.0% by mass, based on the total toner base particles.

The method of adding the external additive to the toner base particles is not particularly limited. Examples of methods for adding external additives to toner base particles include a dry method in which the external additive is added in powder form to dried toner base particles and mixed. As a mixing device for the external additive, a known mixing device such as a turbular mixer, Henschel mixer, Nauta mixer, V-type mixer, etc. can be used. For example, when using a Henschel mixer, it is preferable to set the circumferential speed of the tip of the stirring blade to 30 to 80 m/s, and stir and mix at 20 to 50° C. for about 10 to 30 minutes.

The charge control agent is not particularly limited as long as it is a substance that can impart positive or negative charge through triboelectric charging, and known positive charge control agents and negative charge control agents can be used. The content of the charge control agent is preferably 0.01 to 30.0 parts by weight, more preferably 0.1 to 10.0 parts by weight, based on 100.0 parts by weight of the resin.

A known magnetic material can be used as the magnetic material. Examples of magnetic materials include ferromagnetic metals such as iron, nickel, and cobalt, alloys containing these ferromagnetic metals, compounds of ferromagnetic metals such as ferrite and magnetite, and compounds that do not contain ferromagnetic metals but can be made ferromagnetic by heat treatment. This includes alloys that exhibit Examples of alloys that exhibit ferromagnetism upon heat treatment include Heusler alloys such as manganese-copper-aluminum and manganese-copper-tin, chromium dioxide, and the like.

The particle size of the toner base particles is preferably small for the purpose of improving image quality, and from the viewpoint of chargeability, fluidity, and adhesion, the volume-based median diameter (D50) of the toner base particles is 2.0 to 8. The thickness is preferably .0 μm, more preferably 4.0 to 7.0 μm. Further, it is preferable that the volume-based median diameter (D50) is within the above range because development, transfer, and cleaning become easy.

The volume-based median diameter (D50) of toner particles can be measured and calculated using a device that is connected to a "Multisizer 3" (manufactured by Beckman Coulter) and a computer system for data processing. The measurement procedure is to add 0.02 g of toner particles to 20 ml of a surfactant solution (for example, a surfactant solution prepared by diluting a neutral detergent containing a surfactant component 10 times with pure water for the purpose of dispersing the toner particles). After blending, ultrasonic dispersion is performed for 1 minute to prepare a toner particle dispersion. Pipette this toner particle dispersion into a beaker containing ISOTON II (manufactured by Beckman Coulter) in the sample stand until the measured concentration is 5.0 to 10.0%, and the measuring device count is 25,000. Set and measure. Note that the multisizer 3 used has an aperture diameter of 100 μm. The frequency number is calculated by dividing the measurement range of 1.0 to 30.0 μm into 256, and the particle diameter of 50% of the particles with the larger volume integrated fraction is defined as the volume-based median diameter (D50).

The average circularity of the toner base particles is preferably 0.945 or more, which is closer to a spherical shape, from the viewpoint of charging rise and fluidity. The average circularity is the arithmetic mean value obtained by adding up the circularity of each particle and dividing by the total number of particles measured. Note that the average circularity can be determined using a wet flow particle size/shape analyzer "FPIA-3000" (manufactured by Sysmex Corporation).

The circularity of the toner base particles is measured by wetting the toner particles in an aqueous surfactant solution, performing ultrasonic dispersion for 1 minute, and then using the above-mentioned analyzer under measurement conditions HPF (high magnification imaging) mode. Measurement can be performed at an appropriate concentration with 3000 to 10000 HPF detections. Within this range, reproducible measurement values can be obtained. Circularity can be calculated using the following formula.
Circularity = Perimeter of a circle with the same projected area as the particle image / Perimeter of the particle projection image

The resin layer described above is a layer made of a toner image formed by an electrophotographic method, and is preferably a resin layer made of toner particles fixed to a recording medium. If toner particles are used, an electrophotographic image forming method can be used, so the resin layer can be easily formed. Furthermore, since the resin layer composed of toner particles has a storage elastic modulus G' of 1.0×10 ³ Pa or more and 1.0×10 ⁷ Pa or less, it is easily softened by applying heat. By transferring the powder onto the surface of the resin layer, it is possible to easily create an image having sufficient gloss and metallic feel (mirror tone/pearl tone).

Further, a developer can be manufactured by mixing the above-described toner particles and carrier particles using a mixing device. Examples of mixing devices include Henschel mixers, Nauta mixers, and V-mixers. The ratio of toner particles to the total of toner particles and carrier particles (toner concentration) is preferably 4.0 to 8.0% by mass. When the ratio of toner particles is 4.0 to 8.0% by mass, the amount of charge of the toner becomes appropriate, and the image quality at the initial stage and after continuous printing becomes better.

Here, the term "carrier particles" refers to particles whose surfaces are coated with a coating resin. Furthermore, the term "carrier core material particles" refers to metal powder such as iron powder, various ferrite particles, or particles in which these particles are dispersed in a resin.

In this way, a resin image with a thermoplastic resin layer formed on the recording medium is formed.

1-2. Powder Supply Process The powder supply process involves transferring powder to the opening of the storage container using a conveying member (for example, a rotating cylindrical brush or sponge, or a screw-shaped member) placed inside the storage container. This is the step of transporting the powder to a powder holding member (described later). The powder supply step is not particularly limited as long as the powder can be supplied to the powder holding member. The powder holding member is preferably a cylindrical member that is rotated around a cylindrical shaft by a drive motor, and preferably has a cylindrical side peripheral surface as a powder holding surface. The powder holding surface preferably has adhesive properties, since the powder adheres to the surface.

1-3. Powder Orientation Process The powder orientation process is a process of aligning the orientation of the powder adhering to the powder holding surface of the powder holding member. A method of aligning the orientation of the powder includes rubbing the surface of the powder adhering to the powder holding surface of the powder holding member with an orienting member (for example, a brush, sponge, or porous material such as a nonwoven fabric). There is a way to do it. In addition, the powder orientation process is not particularly limited as long as the powder attached to the powder holding surface can be aligned in the same direction. If so, it can also be carried out by attracting the powder from inside the powder holding member using magnetic force. Here, "rubbing" refers to moving the orientation member, which is placed in contact with the powder holding surface of the powder holding member, relative to the powder holding surface.

Further, from the viewpoint of orienting the powder on the powder holding surface of the powder holding member, it is preferable that the rubbing is accompanied by pressing. "Press" means to press the surface of the powder in a direction transverse to the surface of the powder (for example, in a perpendicular direction).

If the sliding speed is too slow, the orientation of the powder along the powder holding surface may be insufficient, and if the sliding speed is too fast, the adhesion of the powder may be insufficient. Poor orientation of the powder along the holding surface may result, reducing the clarity of the desired appearance in the final image. From the viewpoint of sufficiently adhering and orienting the powder on the powder holding surface of the powder holding member, the relative speed difference of the orientation member to the powder holding surface of the powder holding member should be 5 mm/sec to 500 mm/sec. It is preferably 50 mm/sec to 250 mm/sec, and more preferably 50 mm/sec to 250 mm/sec.

Sliding occurs when the contact width of the orientation member with the powder holding surface of the powder holding member is too narrow, which tends to cause variations in the orientation of the powder when the orientation member moves along the powder holding surface. The orientation of the powder adhering to the holding surface may be insufficient, and if the contact width is too wide, it becomes difficult to convey the recording medium. From the viewpoint of fully realizing the desired orientation of the powder adhering to the powder holding surface, the contact width is preferably 1 mm to 200 mm, which is the length in the moving direction of the orientation member with respect to the powder holding surface. .

If the rubbing force is too low, the powder may peel off from the powder holding surface before being transferred to the resin layer, and if it is too high, the powder may be difficult to transfer to the resin layer. . From the viewpoint of efficiently transferring the oriented powder to the resin layer, the pressing force is preferably 1 to 10 kPa, more preferably 1 to 5 kPa.

The orientation member may be a rotating member or a non-rotating member such as a reciprocating member or a fixed member. The orientation member may be a member that rotates relative to the powder holding surface with a rotation axis in a direction perpendicular to the powder holding surface, or may be a rotatable roller that contacts the powder holding surface. The shape of the orientation member includes a cylinder, an ellipse, and a polygon. Among these, the shape of the orientation member is preferably cylindrical.

The orientation member is configured such that its surface is movable relative to the surface of the powder while pressing the powder holding surface. The rubbing by the orientation member can be achieved, for example, by sliding the powder with a fixed orientation member while the powder is being transported by the powder holding member, or by sliding the powder at a speed slower than the transport speed when the powder is being transported. By rubbing with a roller that rotates at a high speed, or by rubbing with a roller that rotates in the opposite direction to the conveying direction during conveyance, or by rubbing with a roller that rotates in the opposite direction to the conveying direction, or when the axis of rotation is oblique to the conveying direction. This can be done by rubbing with rotatable rollers arranged in the following directions.

Further, it is preferable that the alignment member has flexibility. The flexibility of the alignment member is, for example, such that the surface of the alignment member deforms to the extent that it can follow the shape of the surface of the powder when pressed (deformation followability). Examples of such flexible orientation members include sponges and brushes.

1-4. Powder Transfer Process The powder transfer process is a process in which the powder oriented on the powder holding surface of the powder holding member in the powder orientation process is transferred onto the surface of the softened resin layer. The method of transferring the powder to the resin layer is not particularly limited as long as the oriented powder can be transferred from the powder holding surface to the resin layer.

Examples of methods for softening the resin layer include placing the recording medium on which the resin layer is placed on a hot plate with the image side facing up and heating the recording medium from the bottom side; There are methods of heating the recording medium with a heater from above), applying a softening agent to the surface of the resin layer to soften the resin layer, and softening the recording medium by irradiating it with light from above or below.

When the resin layer is softened by heating, it is carried out at a temperature at which the resin layer is softened and powder is attached (hereinafter also referred to as "adhesion temperature").

The adhesion temperature is determined by gradually raising the temperature of the room-temperature resin layer, and setting the temperature at which the desired image is obtained, for example, the temperature at which the powder starts to stick to the surface of the resin layer for mirror-like/pearl-like images. It can be obtained by detecting.

Further, the deposition temperature is preferably 65 to 150°C, more preferably 70 to 110°C, from the viewpoint of obtaining an image with sufficient gloss and metallic feel (mirror tone/pearl tone). For example, when the recording medium used is a resin film, the temperature can be appropriately selected depending on the type of resin film, the thickness of the resin film, the ease with which the resin layer softens, and the like. Further, the above temperature can be appropriately selected depending on the desired texture (gloss).

Also, in the method of heating with a heater from the image surface side (upper side), the adhesion temperature can be determined in the same manner as the above method.

In addition, when softening the resin layer by applying a softener, the adhesion temperature should be set so that the temperature of the recording medium is lower than the temperature at which deformation occurs in the recording medium, or the temperature at which the powder deteriorates, discolors, or deforms. It is preferable to set the temperature to be lower than the temperature at which the

The softener is not particularly limited as long as it can soften the resin layer. Examples of softeners include organic solvents, alcohols, ketones, esters, ethers, or solutions containing them, and specifically, isobutyl adipate, tetrahydrofuran, or solutions containing them. included. It is thought that when a softening agent is applied to the surface of the resin layer, the resin constituting the resin layer partially dissolves or the resin swells, thereby softening the resin layer.

The method of applying the softener is not particularly limited as long as the softener can be applied to the surface of the resin layer. Examples of methods for applying the softener include spray coating, inkjet coating, coating with a dispenser, and the like. The softener may be applied before supplying the powder, or may be applied simultaneously with the supply of the powder. The amount of the softener applied is not particularly limited and can be arbitrarily adjusted depending on the resin layer, powder, desired decorative effect, etc. Even if the resin layer is sufficiently softened, the resin layer will not adhere. It is enough to just begin to have the ability.

Further, when softening the resin layer by light irradiation, there is no particular limitation as long as the method does not discolor or deteriorate the resin layer. Examples of light irradiation include ultraviolet irradiation, visible light irradiation, infrared irradiation, laser irradiation, and the like. Among the above-mentioned light irradiation methods, it is preferable to use ultraviolet light because it is easy to handle and can soften the resin layer at a sufficient rate. In particular, when the resin layer is a toner image, the light irradiation is preferably performed with ultraviolet light from the viewpoint of easily softening the resin layer containing toners of different colors.

The powder can be transferred to the surface of the softened resin layer using any of the methods described above. Thereby, it is possible to form a decorative image in which the resin layer and the powder are in contact with each other.

Powder is a collection of powder particles. For example, when it is desired to obtain a decorative effect with a metallic feel, the powder is preferably a powder particle containing metal powder or metal oxide powder. Examples of powder particles include metal particles, resin particles, particles containing heat-responsive materials, magnetic particles, non-magnetic particles, and the like. Further, the powder particles may be made of two or more different materials. The shape of the powder particles may be spherical particles or non-spherical particles. The powder may be a synthetic product or a commercially available product. The powder may be a mixture of two or more different types of powder particles. Note that the powder is not toner.

Moreover, the above-mentioned powder particles may be coated. For example, the metal particles may be coated with a metal different from the metal, a metal oxide, or a resin, or may be coated with a metal or metal oxide on the surface of a resin, glass, or the like. Further, the metal particles may be metal oxide particles, or may be coated with a metal oxide, metal, or resin different from the metal oxide. Furthermore, the metal particles may be metal or metal oxide spread into a plate shape and crushed, or coated with various materials, or film or glass coated with metal or metal oxide by vapor deposition or wet coating. . In order to obtain a metallic image, the metal particles preferably contain a metal or a metal oxide, and the content of the metal or metal oxide is preferably 0.2 to 100% by mass.

From the viewpoint of oriented the powder along the powder holding surface and then transferring it to the surface of the resin layer, the powder has a shape that is not a perfect sphere (non-spherical powder), for example, It is preferable that the particles have a flat particle shape. "Flat particle shape" means that the maximum length of a powder particle is the major axis, the maximum length in the direction perpendicular to the major axis is the minor axis, and the minimum length in the direction perpendicular to the major axis is the thickness. This refers to a shape in which the ratio of the short axis to the thickness is 5 or more.

The thickness of the powder is preferably 0.2 to 10 μm, more preferably 0.2 to 3.0 μm, from the viewpoint of sufficiently expressing the appearance effect due to the adhesion of oriented powder. If the thickness of the powder is too small, the powder adhered to the surface of the resin layer has a good orientation in which the plane direction of the powder including the major axis direction and the minor axis direction substantially follows the surface direction of the resin layer. The state may not be fully formed. If the thickness is too large, powder may come off when the image is rubbed.

Examples of the powders mentioned above include Metashine (manufactured by Nippon Sheet Glass Co., Ltd., "Metashine" is a registered trademark of the company), Sunshine Baby Chrome Powder, Aurora Powder, Pearl Powder (all manufactured by GG Corporation). , ICEGEL Mirror Metal Powder (manufactured by TAT Co., Ltd.), Pika Ace MC Shine Dust, Effect C (manufactured by Kurachi Co., Ltd., "Pica Ace" is a registered trademark of the same company), PREGEL Magic Powder, Mirror Series (manufactured by Preampa Co., Ltd., "PREGEL") is a registered trademark of the company), Bonnail Shine Powder (manufactured by K's Planning Co., Ltd., "BON NAIL" is a registered trademark of the company), Elgy neo (manufactured by Oike Kogyo Co., Ltd., "Elgy neo" is a registered trademark of the company), Contains astro flake (manufactured by Nippon Humidity Industry Co., Ltd.) and aluminum pigment (manufactured by Toyo Aluminum Co., Ltd.).

Thermoresponsive materials are materials that undergo shape changes such as expansion, contraction, and deformation, and color changes such as color development, decolorization, and discoloration, when stimulated by heat. Examples of particles comprising thermoresponsive materials include thermally expandable microcapsules, temperature sensitive capsules, and the like. Examples of thermally expandable microcapsules include Matsumoto Microspheres (manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.) and Kureha Microspheres (manufactured by Kureha Co., Ltd.), and examples of thermosensitive capsules include thermosensitive dye capsules (manufactured by Kureha Co., Ltd.). (manufactured by the company Nippon Capsule Products), etc.

A rubbing process may be further included after the powder transfer process.

Note that in the above embodiment, the formation of a resin image and the decoration of the formed resin image with powder are performed continuously and integrally. The resin image may be decorated by transferring oriented powder onto the surface.

2. Image Forming Apparatus An image forming apparatus 10 according to an embodiment of the present invention will be described with reference to FIG. The image forming apparatus 10 includes a resin image forming section 60 and a surface treatment section 70, as shown in FIG. The resin image forming section 60 is a part that forms a resin image including a recording medium and a thermoplastic resin layer disposed thereon. The surface treatment section 70 is a section that processes and decorates the surface of the resin image formed by the resin image forming section 60.

2-1. Resin Image Forming Unit The resin image forming unit 60 has a configuration similar to that of a known color printer. The resin image forming section 60 includes an image reading section, an image forming section, a recording medium transport section, a feeding recording medium section, a data reception section, a control section, and a fixing section 27.

The image reading section includes a light source 11, an optical system 12, an image sensor 13, and an image processing section 14.

In the image reading section, light emitted from a light source 11 is irradiated onto a document placed on a reading surface, and the reflected light is transmitted through a lens and a reflecting mirror of an optical system 12 to an image sensor 13 that has been moved to a reading position. image is formed. The image sensor 13 generates an electrical signal according to the intensity of light reflected from the original. The generated electric signal is converted from an analog signal to a digital signal in the image processing section 14, and then subjected to correction processing, filter processing, image compression processing, etc., and is stored in the memory of the image processing section 14 as image data. Ru. In this way, the image reading section reads the image of the document and stores the image data.

The image forming section includes an image forming section that forms an image made of yellow (Y) toner, an image forming section that forms an image made of magenta (M) toner, an image forming section that forms an image made of cyan (C) toner, It has an image forming section that forms an image made of black (K) toner, and an intermediate transfer belt 26. Note that Y, M, C, and K represent toner colors.

The image forming section includes a photosensitive drum 21 as a rotating body, and a charging section 22, an optical writing section 23, a developing device 24, and a drum cleaner 25 arranged around the photosensitive drum 21. The intermediate transfer belt 26 is wound around a plurality of rollers and supported so as to be movable.

The photosensitive drum 21 is rotated at a predetermined speed by a drum motor. The charging unit 22 charges the surface of the photoreceptor drum 21 to a desired potential, and the optical writing unit 23 writes an image information signal to the photoreceptor drum 21 based on the image data, and writes image information to the photoreceptor drum 21. Forming a latent image based on the signal. The latent image is then developed by the developing device 24, and a toner image that is a visible image is formed on the photoreceptor drum 21. In this way, unfixed toner images of yellow, magenta, cyan, and black are formed on the photoreceptor drums 21 of each YMCK image forming section, respectively. In this way, the image forming section forms a toner image using an electrophotographic image forming process.

The toner images of each color formed by the YMCK image forming sections are sequentially transferred onto the running intermediate transfer belt 26 by the primary transfer section. In this way, a color toner image in which yellow, magenta, cyan, and black toner layers are superimposed is formed on the intermediate transfer belt 26.

In the recording medium conveyance section, the recording medium S is sent out one by one to the conveyance path from the feeding recording medium trays 41, 42, and 43 of the feeding recording medium section by a feed roller 31 and a sorting roller 32. The recording medium S sent out to the conveyance path is conveyed along the conveyance path by the conveyance roller 33 via the loop roller 34 and the registration roller 35 to the secondary transfer roller. Then, the color toner image on the intermediate transfer belt 26 is transferred onto the recording medium S.

The fixing section 27 applies heat and pressure to the recording medium S onto which the color toner image has been transferred, thereby fixing the color toner image on the recording medium S to the recording medium S as a color toner layer. In this way, a resin image including a resin layer formed on the recording medium S is produced. The resin image including the resin layer formed on the recording medium S is sent to the surface treatment section 70 via the discharge recording medium roller 36.

Note that the fixed recording medium S can be guided to the recording medium reversing section 37, and the recording medium S can be turned over and discharged. Thereby, images can be formed on both sides of the recording medium S.

The control unit includes a CPU (Central Processing Unit), a RAM (Random Access Memory), and a ROM (Read Only Memory). The CPU controls the image reading section, the image forming section, the recording medium transport section, the feeding recording medium section, and the surface processing section according to the program stored in the ROM, and stores calculation results and the like in the RAM. The control unit also performs control to analyze print data received from the outside, generate bitmap format image data, and form an image on the recording medium S based on the image data. The above program includes a program for adjusting the amount of softener supplied to the surface treatment section and a program for setting the rubbing conditions.

The control unit also exchanges various data with an external device (for example, a personal computer) connected to a communication network such as a LAN (Local Area Network) or a WAN (Wide Area Network) via a communication unit (not shown). Send and receive. The control unit receives, for example, image data transmitted from an external device or input data received by the data reception unit regarding a decorated image to be formed, and performs processing based on this image data (input image data). An image is formed on the recording medium S. The communication unit is composed of, for example, a communication control card such as a LAN card.

The resin image formed by the resin image forming section 60 is conveyed to the surface treatment section 70 and decorated.

Next, the surface treatment section 70 will be explained using FIG. 2.

2-2. Surface Treatment Section As shown in FIG. 2, the surface treatment section 70 includes a heating member 110 for softening the thermoplastic resin layer 100, a powder holding member 120 for holding the powder P, and a storage container 130. a powder supply member 140 for supplying the powder P stored in the powder supply member 140; an orientation member 150 for orienting the powder supplied from the powder supply member 140 on the surface of the powder holding member 120; It includes a facing member 160 that is provided at a position facing the powder holding surface 121 of the member 120 and for disposing the powder P on the surface of the softened thermoplastic resin layer 100, and a surplus powder collecting member 170.

2-3. Heating Member The heating member 110 is a member for adjusting the temperature of the thermoplastic resin layer 100 to which powder is transferred. The heating member 110 may be a heating device, a cooling device, or a device having both functions. Heating member 110 can be any known device, examples of which include hot plates, ovens, and blowers.

2-4. Powder Holding Member The powder holding member 120 is a cylindrical member with an outer diameter of 75 mm, for example, which is rotated around a cylindrical shaft by a drive motor, and the cylindrical side surface is connected to the powder holding surface 121. It is said that The powder holding surface 121 of this powder holding member 120 has adhesive properties and holds powder P, which will be described next, by the adhesive.

The powder holding surface 121 preferably has an adhesive force (also referred to as adhesive force) of 28 kPa or more. Further, the adhesive force of the powder holding surface 121 is a range in which the powder P is transferred from the powder holding surface 121 to the thermoplastic resin layer 100 when the thermoplastic resin layer 100 develops adhesive force. It is preferable. Therefore, the adhesive force of the powder holding surface 121 is preferably 470 kPa or less, more preferably 350 kPa or less. Thereby, the powder P can be transferred from the powder holding surface 121 to the thermoplastic resin layer 100. Examples of materials constituting such powder holding surface 121 include fluororubber, silicone rubber, urethane rubber, and the like. Further, the material constituting the powder holding surface 121 is not limited to rubber materials, and may be other resin materials or metal materials as long as they have adhesive strength that can hold the powder. good.

The adhesive strength can be measured using a tacking tester "FSR-1000" (manufactured by Resca Co., Ltd.). The adhesive force can be measured as the force required to press the tip of the probe against the sample surface and peel it off. For example, the adhesive force can be measured under the following conditions. Note that the adhesive force can be converted into pressure based on the area of the tip of the probe.
(Measurement condition)
(1) Probe diameter: 10mm in diameter
(2) Pressing speed: 5mm/sec (3) Pressing pressure: 50kPa
(4) Pressing holding time: 1 second (5) Probe lifting speed: 5 mm/second (6) Measurement temperature: 20°C

Further, the powder holding member 120 is disposed on the downstream side of the heating member 110 on the conveyance path of the recording medium S and on the main surface side of the recording medium S on which the thermoplastic resin layer 100 is formed. The powder holding member 120 is configured to rotate in a direction along the conveyance direction (arrow) of the recording medium S on the side facing the recording medium S. Note that when the thermoplastic resin layer 100 is heated by the heating member 110 to develop adhesiveness, the heat is also transmitted to the powder holding member 120, so the material constituting the powder holding member 120, especially the powder holding surface 121 It is preferable that the material constituting the material has heat resistance. Among the rubber materials mentioned above, silicone rubber (adhesive strength: 80 kPa) is preferable as such a material.

2-5. Powder Supply Member The powder supply member 140 is for supplying the powder P to the powder holding surface 121 of the powder holding member 120, and is arranged along the axial direction of the cylindrical powder holding member 120. It is provided. Such a powder supply member 140 includes a storage container 130 that stores powder P, and a conveying member (not shown) accommodated in the storage container 130.

Among these, the storage container 130 has an opening disposed along the axial direction of the powder holding surface 121 of the cylindrical powder holding member 120.

Further, the conveying member is, for example, a rotating cylindrical brush or sponge, or a screw-shaped member. By rotating in the opposite direction to the powder holding member 120, this conveying member conveys the powder P stored in the storage container 130 to the opening of the storage container 130, and transfers the powder P stored in the powder holding member 120. Powder P is supplied to the holding surface 121.

Note that the powder supply member 140 is not limited to such a configuration, and for example, the powder holding surface 121 of the powder holding member 120 is directly applied to the powder P stored in the storage container 130. It may be of a configuration in which they are brought into contact with each other.

2-6. Orientation Member The orientation member 150 is for orienting the powder P on the powder holding surface 121 of the powder holding member 120 by rubbing the powder holding surface 121 of the powder holding member 120. It is arranged downstream of the powder supply member 140 with respect to the rotational direction of the body holding member 120. The shape of the orientation member includes a cylinder, an ellipse, and a polygon. Among these, the shape of the orientation member is preferably cylindrical.

This orientation member 150 has a cylindrical shape, and is configured to rub against the powder holding surface 121 of the rotating powder holding member 120 by being placed in contact with the powder holding surface 121. . Further, it is preferable that the side surface of the orientation member 150 that rubs against the powder holding surface 121 is made of a material having a void for accommodating the powder P. Such materials include, for example, brushes, sponges, or porous materials such as non-woven fabrics.

In addition, by rubbing the powder holding surface 121 of the rotating powder holding member 120, the orienting member 150 moves the powder P supplied to the powder holding surface 121 having adhesiveness to the powder holding surface 121. Remove excess powder P that is not attached to 121. At this time, excess powder P is captured in the gap on the side peripheral surface of the orientation member 150. Further, the orientation member 150 may include a powder collection member (not shown).

As a result, one layer of powder P is left directly adhered to the adhesive powder holding surface 121. At this time, as will be explained in detail later, if the powder P has a non-spherical shape, the powder P is rubbed by the orientation member 150 on the powder holding surface 121, so that the powder P is rubbed against the powder holding surface 121. The directionality of the powder P can be made uniform.

Further, it is preferable that the orientation member 150 is configured to rotate around a cylindrical axis. As a result, the powder P captured and housed in the gap can be continuously transported in the rotational direction, so that the powder P does not accumulate in the nip between the powder holding surface 121 and the orientation member 150. The effect of removing excess powder P from the powder holding surface 121 is enhanced. Moreover, this makes it possible to stabilize the sliding property of the powder holding surface 121 by the orientation member 150.

Further, if the rotation direction of the orientation member 150 is the same as the rotation direction of the powder holding member 120, the relative speed of the orientation member 150 with respect to the powder holding member 120 is further increased, and the orientation member 150 causes the powder holding member 120 to The powder holding surface 121 can be rubbed at a higher speed, and a higher rubbing effect can be obtained.

Furthermore, the pressing force of the orientation member 150 against the powder holding surface 121 of the powder holding member 120 is preferably 1 to 10 kPa, more preferably 1 to 5 kPa. If the pressing force is too low, the pressing of the powder holding member 120 in the axial direction will become unstable. On the other hand, if the pressing force is too high, the torque for rotating the orientation member 150 becomes large, which causes uneven driving of the orientation member 150 and material deterioration of the orientation member 150 and the powder holding member 120.

Further, a powder collection member (not shown) provided on the orientation member 150 is arranged to face the side surface of the orientation member 150 and collects the powder P accommodated in the gap on the side surface of the orientation member 150. to recover. Such a powder collection member may be of an air suction type, or a member in the form of a roller or blade may be brought into contact with the side surface of the orientation member 150 to restore the material constituting the side surface of the orientation member 150. The structure may be such that the powder P is ejected from the void by force.

By providing such a powder collection member for the orientation member 150, it becomes possible to maintain the removal effect of the powder P by the orientation member 150, and the sliding property of the powder holding surface 121 by the orientation member 150 is improved. can be maintained for a long period of time. Note that the above-described orientation member 150 may have a structure that also serves as a conveyance member in the powder supply member 140.

2-7. Opposing member The opposing member 160 is for transferring the powder P adhesively held on the powder holding surface 121 of the powder holding member 120 to the thermoplastic resin layer 100 formed on the main surface of the recording medium S. It is. This opposing member 160 is roller-shaped, and forms a nip portion between which the recording medium S is held between the opposing member 160 and the powder holding member 120 . As a result, the powder P is adhesively held in an oriented state on the powder holding surface 121 of the powder holding member 120 with respect to the thermoplastic resin layer 100 which has been melted and developed stickiness by heating with the heating member 110. They are brought into contact and pressed, and the oriented powder P is transferred from the powder holding surface 121 to the thermoplastic resin layer 100. Further, since the thermoplastic resin layer 100 is in a softened stage after passing through the heating member 110, adhesiveness is developed due to the softening, and the powder P is adhered and held on the thermoplastic resin layer 100. Thereby, a glossy image in which the glossy powder P is pasted on the surface of the thermoplastic resin layer 100 can be obtained.

2-8. Surplus Powder Collection Member The surplus powder collection member 170 is for collecting the excess powder P on the recording medium S that has passed through the nip between the powder holding member 120 and the opposing member 160. This surplus powder collecting member 170 is located on the downstream side of the nip portion between the powder holding member 120 and the opposing member 160 on the conveyance path of the recording medium S, and on the side of the recording medium S where the thermoplastic resin layer 100 is formed. will be placed in Here, it is assumed that the excess powder P on the recording medium S is the powder P that is not adhered and held by the thermoplastic resin layer 100.

An example of such a surplus powder collecting member 170 is one having a configuration that sucks the powder P by air suction, but the present invention is not limited thereto.

Although the surface treatment section 70 is combined with the resin image forming section 60 as shown in FIG. 1, the surface treatment section 70 alone may be used as an image forming apparatus. Alternatively, the surface treatment section 70 may be incorporated into a color printer and configured integrally with the color printer.

Hereinafter, specific examples of this embodiment will be described together with comparative examples. However, the technical scope of the present invention is not limited only to the following examples.

1. Preparation of Dispersion Liquid (A-1) of Amorphous Resin Fine Particles A dispersion liquid (A-1) of amorphous resin fine particles was prepared according to the following procedure.

(Preparation of resin particles (B-1))
Polyoxyethylene (2) sodium dodecyl ether sulfate (7.0 parts by mass) was ionized into a 5 L reaction vessel (hereinafter referred to as "reaction vessel") equipped with a stirring device, temperature sensor, cooling tube, and nitrogen introduction device. A solution dissolved in exchanged water (3000.0 parts by mass) was charged and heated to 98°C. After heating, a mixed solution in which the following monomers, chain transfer agent, and mold release agent were dissolved at 80°C was added. The stirring speed at this time was 230 rpm.
Styrene 285.0 parts by mass n-Butyl acrylate 91.0 parts by mass Methacrylic acid 13.0 parts by mass n-octyl-3-mercaptopropionate (chain transfer agent) 1.5 parts by mass Paraffin wax (mold release agent, melting point 77°C) 135.0 parts by mass

Using a mechanical dispersion machine "CLEARMIX" with a circulation path (M Technique Co., Ltd., "CLEARMIX" is a registered trademark of the company), mixing and dispersing treatment was performed for 1 hour to prepare a dispersion containing emulsified particles (oil droplets). did. A solution of a polymerization initiator in which potassium persulfate (6.0 parts by mass) was dissolved in ion-exchanged water (200.0 parts by mass) was added to this dispersion, and the resulting mixture was heated to 84°C for 1 hour. Polymerization was carried out by heating and stirring for a period of time to obtain resin particles (B-1).

(Preparation of aqueous dispersion (A-1) of amorphous resin fine particles)
In a reaction container, resin particles (B-1) (524.0 parts by mass/solid content equivalent) and ion-exchanged water (400.0 parts by mass) were charged, and after mixing well, potassium persulfate (11.0 parts by mass) was charged. ) dissolved in ion-exchanged water (400.0 parts by mass) was added. Furthermore, under a temperature condition of 82° C., a mixed solution of the following monomer and chain transfer agent was added dropwise over 1 hour. Note that the solid content equivalent is the total amount of the compounds in the resin particles (B-1) excluding the chain transfer agent.
Styrene 400.0 parts by mass n-butyl acrylate 165.0 parts by mass Methacrylic acid 30.0 parts by mass n-octyl-3-mercaptopropionate 8.0 parts by mass

After completion of the dropwise addition, polymerization was carried out by heating and stirring for 2 hours, followed by cooling to 28° C. to obtain an aqueous dispersion (A-1) of amorphous resin fine particles. The volume-based median diameter (D50) of the resin particles in the obtained aqueous dispersion (A-1) of amorphous resin particles was 220 nm, the glass transition temperature (Tg) was 48°C, and the weight average molecular weight ( Mw) was 32,000.

The median diameter of the aqueous dispersion (A-1) of amorphous resin fine particles was measured using Microtrack UPA-150 (manufactured by Nikkiso Co., Ltd.).

(Method for measuring glass transition temperature (Tg))
The glass transition temperature (Tg) of the resin particles was measured using "Diamond DSC" (manufactured by PerkinElmer).

3.0 mg of the measurement sample (resin) was sealed in an aluminum pan and set in the sample holder of "Diamond DSC." An empty aluminum pan was used as a reference. Then, a first heating process in which the temperature is raised from 0 to 200 at a heating rate of 10°C/min, a cooling process in which the temperature is cooled from 200 to 0 at a cooling rate of 10°C/min, and a cooling process from 0 to 0 at a heating rate of 10°C/min. A DSC curve was obtained under measurement conditions (heating/cooling conditions) in which the temperature was raised to 200°C in this order. Based on the DSC curve obtained by this measurement, the extension line of the baseline before the rise of the first endothermic peak in the second temperature rising process and the maximum between the rising part of the first peak and the peak apex. A tangent line indicating the slope was drawn, and the intersection thereof was defined as the glass transition temperature (Tg).

(Method for measuring weight average molecular weight (Mw))
The weight average molecular weight (Mw) of the resin particles is determined by connecting the device "HLC-8320GPC" (manufactured by Tosoh Corporation), one column "TSKguardcolumn" and three columns "TSKgelSuperHZ-M" (all manufactured by Tosoh Corporation). Measured using

Tetrahydrofuran (THF) was flowed as a carrier solvent at a flow rate of 0.2 mL/min while maintaining the column temperature at 40°C. The sample solution was prepared by dissolving the measurement sample (resin) in tetrahydrofuran to a concentration of 1 mg/mL, and treating the solution at room temperature for 5 minutes using an ultrasonic disperser. Next, a sample solution was obtained by processing with a membrane filter having a pore size of 0.2 μm, and 10 μL of this sample solution was injected into the apparatus together with the above carrier solvent, and detected using a refractive index detector (RI detector). The molecular weight distribution of the measurement sample was calculated based on a calibration curve created using monodisperse polystyrene standard particles. The calibration curve is manufactured by Tosoh Corporation "polystylene standard sample TSK standard": "A-500", "F-1", "F-10", "F-80", "F-380", "A-2500" , "F-4", "F-40", "F-128", and "F-700". Note that the data collection interval in sample analysis was 300 ms.

Table 1 shows the content (in parts by mass) of each component of fine resin particles B-1 to B-8 contained in aqueous dispersions A-1 to A-8 of fine amorphous resin particles.

Further, aqueous dispersions A-2 to A-8 of amorphous resin fine particles were prepared in the same manner as A-1 except that the content of the above-mentioned components of A-1 was changed. Table 2 shows the content of the components in aqueous dispersions A-2 to A-8.

Each abbreviation shown in Tables 1 and 2 is as follows.

a: Styrene b: n-butyl acrylate c: methacrylic acid d: n-octyl-3-mercaptopropionate (chain transfer agent)
e: Paraffin wax (HNP-51; manufactured by Nippon Seiro Co., Ltd.)

2. Preparation of dispersion C of crystalline polyester resin particles (Preparation of crystalline polyester resin D)
Dodecanedioic acid (440.0 parts by mass) and 1,6-hexanediol (153.0 parts by mass) were charged into a reaction vessel equipped with a stirring device, a nitrogen inlet tube, a temperature sensor, and a rectification column, and the reaction system The temperature was raised to 190° C. over 1 hour, and it was confirmed that the inside of the reaction system was stirred uniformly. Thereafter, titanium tetrabutoxide (Ti(O-n-Bu) ₄ ) (0.3 parts by mass) was added as an esterification catalyst, and the temperature of the reaction system was increased from 150°C to 6°C while distilling off the water produced. A non-hybrid type crystalline polyester resin D was obtained by raising the temperature to 240°C over a period of time and then performing a dehydration condensation reaction for 6 hours while maintaining the temperature at 240°C. The obtained crystalline polyester resin D had a weight average molecular weight (Mw) of 14,500 and a melting point (Tm) of 70°C.

(Preparation of dispersion C of crystalline polyester resin particles)
Crystalline polyester resin D (72.0 parts by mass) was dissolved in methyl ethyl ketone (72.0 parts by mass) by stirring at 70° C. for 30 minutes. Next, a 25% by mass aqueous sodium hydroxide solution (2.5 parts by mass) was added to this solution. The obtained solution was placed in a reaction vessel equipped with a stirrer, and an aqueous solution of sodium polyoxyethylene lauryl ether sulfate dissolved in ion-exchanged water (250.0 parts by mass) to a concentration of 1% by mass was added over 70 minutes. Mixed dropwise. The liquid in the container became cloudy during the dropping, and an emulsion was obtained after the entire amount was dropped.

Next, while keeping the emulsion at 70°C, methyl ethyl ketone was distilled off by stirring under reduced pressure of 15 kPa (150 mbar) using a diaphragm vacuum pump "V-700" (manufactured by BUCHI) for 3 hours. , an aqueous dispersion C of crystalline polyester resin was obtained. As a result of measurement using a laser diffraction particle size distribution analyzer "LA-750 (manufactured by HORIBA)", the volume-based median diameter (D50) of the particles contained in the above dispersion was 132 nm.

3. Preparation of Dispersion Liquid (E) of Amorphous Resin Fine Particles A dispersion liquid (E) of amorphous resin fine particles was prepared according to the following procedure.

(Preparation of amorphous polyester resin (F))
The following raw materials for the polycondensation resin (amorphous polyester resin) were placed in a four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, and heated to 170° C. to dissolve them.
Bisphenol A propylene oxide 2 mole adduct 285.7 parts by mass Terephthalic acid 66.9 parts by mass Fumaric acid 47.4 parts by mass

After dissolution, Ti(OBu) ₄ (0.4 parts by mass) was added as an esterification catalyst to the resulting solution, heated to 235°C, and heated under normal pressure (101.3 kPa) for 5 hours and under reduced pressure (8 kPa). ) for 1 hour. Next, the obtained reaction solution was cooled to 200° C., and the reaction was carried out under reduced pressure (20 kPa) until a desired softening point was reached. After the reaction was completed, the solvent was removed to obtain an amorphous polyester resin (F). The glass transition temperature (Tg) of the amorphous polyester resin (F) was 57°C, and the weight average molecular weight (Mw) was 19,000.

(Preparation of dispersion liquid (E) of amorphous resin fine particles)
Amorphous polyester resin (F) (100 parts by mass) was dissolved in ethyl acetate (400 parts by mass) (manufactured by Kanto Kagaku Co., Ltd.), and the resulting solution and 0.26% by mass of sodium lauryl sulfate prepared in advance The solution (638 parts by mass) was mixed and subjected to ultrasonic dispersion for 30 minutes at a V-LEVEL of 300 μA using an ultrasonic homogenizer "US-150T" (manufactured by Nippon Seiki Seisakusho Co., Ltd.) while stirring. Next, while heating to 40°C, ethyl acetate was completely removed using a diaphragm vacuum pump "V-700" (manufactured by BUCHI) under reduced pressure with stirring for 3 hours, and the amorphous polyester resin ( A dispersion (E) of amorphous resin fine particles was obtained in which the solid content of the fine particles of F) was 13.5% by mass. The volume-based median diameter of the resin particles was 190 nm.

Note that the measurement of weight average molecular weight (Mw) and the measurement of median diameter were performed using the same apparatus as used for the aqueous dispersion of amorphous resin fine particles (A-1) described above.

4. Preparation of mold release agent dispersion (G) Paraffin wax (mold release agent, melting point 77°C) (60 parts by mass) and ionic surfactant "Neogen RK" (5 parts by mass, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 240 parts by mass of ion-exchanged water was heated to 95°C, thoroughly dispersed using a homogenizer "Ultra Tax T50" (manufactured by IKA), and then subjected to dispersion treatment using a pressure discharge type Gorlin homogenizer. By doing so, a dispersion liquid (G) having a solid content concentration of release agent particles of 20% by mass was prepared. As a result of measurement using a laser diffraction particle size distribution analyzer "LA-750 (manufactured by HORIBA)", the volume-based median diameter (D50) of the release agent particles in the dispersion (G) was 240 nm.

5. Preparation of Colorant Particle Dispersion (H) Sodium dodecyl sulfate (90 parts by mass) was stirred and dissolved in ion exchange water (1600 parts by mass). While stirring this solution, C. I. Pigment Red 122 (quinacridone) (420 parts by weight) was gradually added. Next, a colorant particle dispersion liquid 1 in which colorant particles were dispersed was prepared by performing a dispersion treatment using a mechanical dispersion machine "Clearmix". The dispersion diameter of the colorant particles in the colorant particle dispersion 1 was measured using Microtrac UPA-150 (manufactured by Nikkiso Co., Ltd.), and the median diameter on a volume basis was 205 nm.
(Measurement condition)
Sample refractive index: 1.59
Sample specific gravity: 1.05 (converted to spherical particles)
Solvent refractive index: 1.33
Solvent viscosity: 0.797 (30°C), 1.002 (20°C)
Zero-point adjustment: Adjustment was made by adding ion-exchanged water to the measurement cell.

6. Preparation of toner particles 6-1-1. Preparation of Toner Base Particles 1 Aqueous dispersion of amorphous resin particles (A-1) (360.0 parts by mass (solid content)) and ions were placed in a reaction vessel equipped with a stirring device, a temperature sensor, and a cooling tube. Exchange water (2000.0 parts by mass) was added. At room temperature (25° C.), a 5 mol/L aqueous sodium hydroxide solution was added to adjust the pH of the dispersion to 10. Furthermore, colorant particle dispersion H (30.0 parts by mass (solid content)) was added, and a solution of magnesium chloride (60.0 parts by mass) dissolved in ion-exchanged water (60.0 parts by mass) was added. was added over 10 minutes at 30° C. with stirring. After leaving it for 3 minutes, the temperature was raised to 80°C over 60 minutes, and after the liquid temperature reached 80°C, the stirring speed was adjusted so that the particle size growth rate was 0.01 μm/min, and the Coulter Mulch was heated. It was grown until the volume-based median diameter measured with Sizer 3 (manufactured by Coulter Beckman) was 6.0 μm. Thereafter, an aqueous solution in which sodium chloride (190.0 parts by mass) was dissolved in ion-exchanged water (760.0 parts by mass) was added to stop the growth of the particle size.

Furthermore, by heating and stirring at 84°C, the particles were fused together, and when the average circularity reached 0.970 using a toner average circularity measuring device "FPIA-3000", 2. Cooled to 30°C at a cooling rate of .5°C/min.

Next, solid-liquid separation, redispersion of the dehydrated toner cake in ion-exchanged water, and solid-liquid separation were repeated three times for washing, followed by drying at 40° C. for 24 hours to obtain toner base particles 1. .

6-1-2. Preparation of Toner Base Particles 2 Toner base particles 2 are prepared by adding aqueous dispersion A-1 (360.0 parts by mass (solid content equivalent)) used in toner base particles 1 to aqueous dispersion A-2 (360 parts by mass). Toner base particles 1 were prepared in the same manner as toner base particles 1, except that the solid content was changed to (based on solid content).

6-1-3. Preparation of Toner Base Particles 3 Toner base particles 3 were prepared as follows except that aqueous dispersion A-1 (360.0 parts by mass) used in toner base particles 1 was changed to aqueous dispersion A-3 (360 parts by mass). , was prepared in the same manner as toner base particles 1.

6-1-4. Preparation of Toner Base Particles 4 Toner base particles 4 were prepared as follows except that aqueous dispersion A-1 (360.0 parts by mass) used in toner base particles 1 was changed to aqueous dispersion A-4 (360 parts by mass). , was prepared in the same manner as toner base particles 1.

6-1-5. Preparation of toner base particles 5 Toner base particles 5 were prepared as follows except that aqueous dispersion A-1 (360.0 parts by mass) used in toner base particles 1 was changed to aqueous dispersion A-5 (360 parts by mass). , was prepared in the same manner as toner base particles 1.

6-1-6. Preparation of Toner Base Particles 6 Toner base particles 6 were prepared as follows except that aqueous dispersion A-1 (360.0 parts by mass) used in toner base particles 1 was changed to aqueous dispersion A-6 (360 parts by mass). , was prepared in the same manner as toner base particles 1.

6-1-7. Preparation of toner base particles 7 Aqueous dispersion A-6 of amorphous resin particles (324.0 parts by mass (solid content)) and crystalline polyester were placed in a reaction vessel equipped with a stirring device, a temperature sensor, and a cooling tube. Dispersion liquid C of resin particles (36.0 parts by mass (solid content equivalent)) and ion exchange water (2000.0 parts by mass) were charged. At room temperature (25° C.), a 5 mol/L aqueous sodium hydroxide solution was added to adjust the pH of the dispersion to 10. Furthermore, colorant particle dispersion H (30.0 parts by mass (solid content)) was added, and a solution of magnesium chloride (60.0 parts by mass) dissolved in ion-exchanged water (60.0 parts by mass) was added. was added over 10 minutes at 30° C. with stirring. After leaving it for 3 minutes, the temperature was raised to 80°C over 60 minutes. After the liquid temperature reached 80°C, the stirring speed was adjusted so that the particle size growth rate was 0.01 μm/min, and Coulter Mulch was added. It was grown until the volume-based median diameter measured with Sizer 3 (manufactured by Coulter Beckman) was 6.0 μm. Thereafter, an aqueous solution in which sodium chloride (190.0 parts by mass) was dissolved in ion-exchanged water (760.0 parts by mass) was added to stop the growth of particle size.

Furthermore, by heating and stirring at 84°C, the particles were fused together, and when the average circularity reached 0.970 using a toner average circularity measuring device "FPIA-3000", 2. Cooled to 30°C at a cooling rate of .5°C/min.

Next, the dispersion liquid is subjected to solid-liquid separation, the dehydrated toner cake is re-dispersed in ion-exchanged water, and solid-liquid separation is repeated three times for washing, and then dried at 40° C. for 24 hours to form toner base particles. I got a 7.

6-1-8. Preparation of toner base particles 8 Toner base particles 8 were prepared by changing the aqueous dispersion A-6 (324.0 parts by mass) used in toner base particles 7 to aqueous dispersion A-8 (324.0 parts by mass). Except for this, it was prepared in the same manner as toner base particles 7.

6-1-9. Preparation of toner base particles 9 Toner base particles 9 are prepared by adding aqueous dispersion A-6 (324.0 parts by mass) used in toner base particles 7 to aqueous dispersion A-8 (342.0 parts (solid content equivalent)). ) was prepared in the same manner as toner base particles 7, except that dispersion C of crystalline polyester resin particles (36.0 parts by mass (in terms of solid content)) was changed to 18.0 parts by mass (in terms of solid content). did.

6-1-10. Preparation of toner base particles 10 Aqueous dispersion E (310 parts by mass (solid content equivalent)) and dispersion C of crystalline polyester resin particles (50 parts by mass) were placed in a reaction vessel equipped with a stirring device, a temperature sensor, and a cooling tube. (in terms of solid content)) and ion-exchanged water (1000 parts by mass) were added, and then a 5 mol/L aqueous sodium hydroxide solution was added to adjust the pH to 10.

Colorant particle dispersion H (30 parts by mass (solid content)) and release agent dispersion G (36 parts by mass (solid content)) were added to the obtained dispersion, and while stirring, magnesium chloride ( An aqueous solution prepared by dissolving 60 parts by mass) in ion-exchanged water (60 parts by mass) was added to the above dispersion at 30° C. over 10 minutes. After that, after leaving it for 3 minutes, the temperature was started to increase, and the resulting dispersion was heated to 80°C over 60 minutes, and while maintaining the temperature at 80°C, the growth rate of the particle size became 0.01 μm/min. The stirring speed was adjusted as follows, and the mixture was grown until the volume-based median diameter as measured by Coulter Multisizer 3 (manufactured by Coulter Beckman) was 6.0 μm. Thereafter, an aqueous solution in which sodium chloride (190.0 parts by mass) was dissolved in ion-exchanged water (760.0 parts by mass) was added to stop the growth of the particle size.

Furthermore, by heating and stirring at 85°C, the particles were fused together, and when the average circularity of the toner reached 0.970 using a toner average circularity measuring device "FPIA-3000". Cooled to 30°C at a cooling rate of 2.5°C/min. The above dispersion is solid-liquid separated, the dehydrated toner cake is re-dispersed in ion-exchanged water, and solid-liquid separation is repeated three times for washing, followed by drying at 40° C. for 24 hours to form toner base particles 10. Obtained.

6-1-11. Preparation of toner base particles 11 Toner base particles 11 were prepared using the following toner base particles, except that the aqueous dispersion A-1 (360.0 parts by mass) used in toner base particles 1 was changed to A-7 (360 parts by mass). Prepared in the same manner as Particle 1.

6-1-12. Preparation of toner base particles 12 Toner base particles 12 were prepared using the following toner base particles: Prepared in the same manner as Particle 1.

Table 3 shows the contents of the components contained in the above-mentioned toner base particles 1 to 12.

6-2. Preparation of Toner Particles 1 Silica fine particles A (NAX50; manufactured by Nippon Aerosil Co., Ltd., 1.7 parts by mass) and silica fine particles B (R805) were added as external additives to toner base particles 1 (100.0 parts by mass). ; manufactured by Nippon Aerosil Co., Ltd., 0.3 parts by mass), titanium oxide particles A (first order average particle size 85 nm; surface treated with isobutyltrimethoxysilane, 0.15 parts by mass), titanium oxide particles B ( Toner particles 1 having a primary number average particle size of 20 nm and surface treated with hexyltrimethoxysilane (0.15 parts by mass) were added and mixed using a Henschel mixer.

6-2-2. Preparation of Toner Particles 2 to 12 Toner particles 2 to 12 were prepared in the same manner as toner particles 1, except that toner base particles 1 were changed to toner base particles 2 to 12, respectively.

Table 4 shows the contents of the components contained in toner particles 1 to 12. Note that the units of numerical values shown in Table 4 are parts by mass.

7. Evaluation Decorated images were formed using the prepared toner particles 1 to 12, and the glossiness of each was evaluated.

7-1. Measurement of storage elastic modulus The storage elastic modulus G' of the thermoplastic resin layer composed of toner particles 1 to 12 was measured. The storage modulus G' of the thermoplastic resin was measured using a rheometer (ARES G2, manufactured by TA INSTRUMENT).

(Measurement condition)
Frequency: 1Hz
Heating rate: 3℃/min Axial force: 0g
Sensitivity: 10g
Initial strain: 0.01%
Distortion adjustment: 30.0%
Minimum distortion: 0.01%
Maximum distortion: 10.0%
Minimum torque: 1g・cm
Maximum torque: 80g・cm
Sampling interval: 1.0℃/pt

(Measuring method)
0.2 g of each of Toners 1 to 12 was weighed and pressure molded by applying a pressure of 25 MPa using a compression molding machine to produce cylindrical pellets with a diameter of 10 mm. A parallel plate with a diameter of 8 mm was set on top of the cylindrical pellet, and a parallel plate with a diameter of 25 mm was set below, and the temperature was raised at a frequency of 1 Hz. Samples were set at 100°C, and the gap was set to 1.4 mm. After scraping off the sample that protruded from between the plates, the gap was set to 1.1 mm and heated to 30°C while applying axial force. It was cooled and left to stand for 10 minutes. Thereafter, the application of axial force was stopped, and the storage modulus G' was measured from 30° C. to 100° C. under conditions of a frequency of 1 Hz and a temperature increase rate of 3° C./min. The storage elastic modulus G' at 90°C at this time was defined as the storage elastic modulus G'.

7-2. Image Formation A toner image (Example) was formed using an image forming apparatus according to an embodiment of the present invention shown in FIG. Further, a toner image (comparative example) was formed using the image forming apparatus shown in FIG. 3 of JP-A-2019-005965. Both image forming apparatuses are modified versions of the commercially available multifunction device "AccurioPress C2060" (manufactured by Konica Minolta Co., Ltd., "AccurioPress" is a registered trademark of the company).

(Image forming conditions: Example)
A square patch image of 2 cm x 2 cm was formed on a recording medium using toner particles 1 to 12, and a fixed toner image having the patch image was output on the recording medium. At this time, New Color R Yuki manufactured by Lintec Corporation was used as the recording medium. Further, at this time, the amount of the toner image (toner) attached as the thermoplastic resin layer was 11.0 g/m ² .

7-3. Formation of Decorated Image A decorated image was obtained by subjecting the toner image outputted using the image forming apparatus shown in FIG. 1 to surface treatment in the surface treatment section 70 shown in FIG. In the surface treatment section 70, the temperature of the image on the recording medium is adjusted to a desired temperature using the heat of the heating member, and the powder holding surface 121 and the recording medium S are brought into contact with each other to transfer the powder P to the image. did. In this example, the decorative image was formed by heating the thermoplastic resin layer (image) on the heating member at 100°C or 80°C.

(Rubbing conditions)
(1) Orientation member: Urethane sponge roller (outer diameter: 25 mm, sponge thickness: 6 mm) (Ruby cell roller: manufactured by Toyo Polymer Co., Ltd., "Ruby cell" is a registered trademark of the company)
(2) Powder: Metashine ME2025PS (manufactured by Nippon Sheet Glass Co., Ltd.)
(3) Pressure force during rubbing [N]: 5kPa
(4) Sliding speed: 180 mm/sec (the rotating direction of the powder holding member and the orientation member are the same, and the relative speed of the contacting surfaces)

(Powder holding member)
The powder holding member had a cylindrical shape with an outer diameter of 75 mm, and the holding surface was made of silicone rubber (adhesive force: 80 kPa).

(Image forming conditions: comparative example)
A toner image (using toner particles 4) was output using the image forming apparatus shown in FIGS. 2 and 3 of JP-A-2019-005965, and a decorated image was obtained.

8. Evaluation of glossiness The glossiness of decorated images produced using toner particles 1 to 12 was evaluated.

(Evaluation method)
Regarding the obtained decorative image, the amount of reflected light at an incident angle of 45° was measured while changing the angle of reflected light (light reception) using a variable angle photometer "GP-5" (manufactured by Murakami Color Research Institute Co., Ltd.). . The measurement was performed in a light receiving angle range of 15 to 75°, and the half width of the peak and the integral value (area) of the peak were determined. The following evaluation criteria (integral value (area)) are relative values when the integral value (area) at the image heating temperature (100°C) when using toner particle 11 (comparative example) is taken as 100. be. Further, the evaluation standard (half-width) is a relative value when the half-width at the image heating temperature (100° C.) when toner particles 11 (comparative example) is used is set to 100.

Here, the larger the integral value (area), the more powder is attached (the higher the transfer rate), and the smaller the half-width, the more uniform the orientation. Therefore, those with a large area and a narrow half width have the strongest metallic feel.

(Evaluation criteria: integral value (area))
◎: 120 or more ○: 90 or more and less than 120 △: 70 or more and less than 90 ×: less than 70

(Evaluation criteria: half width)
◎: Less than 75 ○: 75 or more and less than 85 △: 85 or more and less than 95 ×: 95 or more

Table 5 shows the measurement results of the storage modulus G' and the gloss evaluation results. In Table 5, the image forming apparatus according to the embodiment of the present invention shown in FIG. 1 is device (f), and the image forming device shown in FIGS. ).

As is clear from toner particles 1 to 12 shown in Table 5, the storage elastic modulus G' at 90°C when measured from 30°C to 100°C is 1.0 × 10 ³ Pa or more 1.0 × 10 ⁷ Pa It has been found that the following toner particles 1 to 10 forming the resin layer can be used over a wide temperature range of 70 to 100° C. during powder transfer. In particular, toner particles 7 to 9 containing crystalline polyester resin particles and toner particles 10 containing amorphous polyester resin particles and crystalline polyester resin particles produce decorative images that have excellent gloss in the temperature range of 70 to 100°C. It turns out that you can get . This is thought to be because by including the crystalline polyester resin, the gradient of change in storage elastic modulus G' can be made smaller even when the temperature is changed from 30 to 100°C. Thereby, the surface condition of the thermoplastic resin layer can be adjusted to match the desired gloss of the image.

Also, compared to the case where the powder is supplied to the resin layer and then rubbed to align the direction of the powder adhering to the surface of the resin layer, it is possible to reduce the amount of powder adhering to the powder holding surface of the powder holding member. It has been found that by aligning the orientation of the powder and then transferring it to the resin layer, it is possible to obtain an image with sufficient gloss and metallic feel (mirror tone/pearl tone).

According to the present invention, an image having sufficient gloss and metallic appearance can be easily produced. Therefore, according to the present invention, it is expected that the formation of images exhibiting the above-mentioned special appearance will become more widespread.

10 Image forming device 11 Light source 12 Optical system 13 Imaging device 14 Image processing section 21 Photosensitive drum 22 Charging section 23 Optical writing section 24 Developing device 25 Drum cleaner 26 Intermediate transfer belt 27 Fixing section 31 Sending roller 32 Sorting roller 33 Conveyance roller 34 Loop roller 35 Registration roller 36 Discharge recording medium roller 37 Recording medium reversing section 41 to 43 Feeding recording medium tray 60 Resin image forming section 70 Surface treatment section 100 Thermoplastic resin layer 110 Heating member 120 Powder holding member 121 Powder holding member Surface 130 Storage container 140 Powder supply member 150 Orienting member 160 Opposing member 170 Excess powder collection member P Powder S Recording medium

Claims (10)

An image forming method for forming a decorated image by decorating a resin image including a recording medium and a thermoplastic resin layer formed on the recording medium, the method comprising:
a powder orientation step of orienting the powder held on the powder holding surface;
a powder transfer step of transferring the oriented powder onto the surface of the thermoplastic resin layer;
has
In measuring the viscoelasticity of the thermoplastic resin layer, the storage elastic modulus G' at 90°C when measured from 30°C to 100°C under the measurement conditions of a frequency of 1 Hz and a heating rate of 3°C/min is 1.0 × 10 An image forming method in which the pressure is ³ Pa or more and 1.0×10 ⁷ Pa or less. The image forming method according to claim 1, wherein the powder is transferred onto a softened surface of the thermoplastic resin layer. The image forming method according to claim 1 or 2, wherein the thermoplastic resin layer contains a crystalline resin. The image forming method according to any one of claims 1 to 3, wherein the powder orientation step includes a step of rubbing the powder held on a powder holding surface. 5. The image forming method according to claim 4, wherein the rubbing step is a step of rubbing the powder by rotating a cylindrical orientation member. The image forming method according to any one of claims 1 to 5, wherein the powder holding surface holds the powder by having adhesiveness. The image forming method according to any one of claims 1 to 6, wherein the powder is a non-spherical powder. The image forming method according to any one of claims 1 to 6, wherein the powder has a flat particle shape. The image forming method according to any one of claims 1 to 8, wherein the powder has a thickness of 0.2 μm to 3.0 μm. The image forming method according to any one of claims 1 to 9, wherein the powder is a metal powder and/or a metal oxide powder.

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