JP2000185469A - Image forming material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive image forming material than can obtain an image of high density and high resolution, avoid the occurrence of flaws during manufacturing, has high sensitivity during the image forming period, and has no deterioration of an image quality in an image forming process. SOLUTION: The image forming material has a coloring agent layer containing needle ferromagnetic powder A and spherical ferromagnetic powder B as a coloring agent no the carrier, wherein in a ratio between the powder A and the powder B, the powder B is 1 pts.wt. or more and 30 pts.wt. or less with respect to the powder A of 100 pts.wt., and a principal component of the powder B is in a Fe system, and a principal component of the powder B is γ-Fe2O3 or Co-containing iron oxide, and a ratio of the length of a particle major axis is B>A between the powder A and the powder B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus which can obtain a high-density, high-resolution image, is hardly damaged at the time of manufacturing, has high sensitivity at the time of forming an image, and does not involve image quality deterioration in the image forming process. About the material.

[0002]

2. Description of the Related Art Heretofore, there has been known a recording method in which light energy such as a laser beam is focused and irradiated on a recording material to melt or deform a part of the material, or to scatter, burn or evaporate. These are dry treatments that do not require treatment liquids such as chemicals, and have the advantage that a high contrast can be obtained by melting and deforming, scattering and / or evaporating and removing only the light irradiation part (ablation). It is used as a resist material, an optical recording material such as an optical disk, and an image forming material that makes itself a visible image.

[0003] For example, Japanese Patent Application Laid-Open Nos.
JP-A-105638 and JP-A-62-115153 disclose a method of forming a resist pattern by photodecomposing a binder resin by pattern exposure and materials for the same, which are disclosed in JP-A-55-132536, JP-A-57-27788, and JP-A-57-27788. 57
JP-A-103137 discloses that an inorganic compound thin film provided by a vapor deposition method is exposed to light to record information by melting deformation of the film.
No. 87, No. 6-40163 and the like, a material for information recording by removing a colored binder layer by photothermal conversion,
U.S. Pat. No. 4,245,003 and the like each disclose an image forming material having an image forming layer containing graphite or carbon black.

[0004]

When the image forming method described in the above-mentioned U.S. Patent is used, a high-density and high-resolution image can be obtained, but it is effective in increasing sensitivity, improving image quality and preventing scratches during manufacturing. There was no means. In the past, coating properties were improved by changing the coating method, transportability was improved, stains were reduced by using an undercoat layer, high image quality was reduced by additives, and scratches were reduced by various fillers. There were difficulties in adopting them, as they were too crowded and affected other performance.

The present invention has been made in view of the above circumstances, and an object of the present invention is to obtain a high-density, high-resolution image by exposure to high-density energy light, to prevent scratches from being produced during manufacturing, and to form an image. An object of the present invention is to provide an inexpensive image forming material which has high sensitivity at the time and does not involve deterioration of image quality in an image forming step.

[0006]

An object of the present invention is to provide an image having a colorant layer containing a needle-like ferromagnetic powder (A) and a spherical ferromagnetic powder (B) as a colorant on a support. The forming material, the ratio of the powder (A) to the powder (B) is not less than 1 part by weight and not more than 30 parts by weight based on 100 parts by weight of the powder (A); Is Fe-based, and the main component of powder (B) is γ-Fe ₂ O ₃ or Co.
Containing iron oxide, and powder (A) and powder (B)
In which the length ratio of the major axis of the particles is (B)> (A).

Hereinafter, the present invention will be described in detail.

[0008] The image forming material of the present invention is characterized in that a colorant layer coated on a (transparent) support contains acicular ferromagnetic powder and spherical or amorphous ferromagnetic powder.

As the support, acrylates, methacrylates, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyarylate, polyvinyl chloride, polyethylene, polypropylene, polystyrene, nylon, aromatic polyamide, polyether Examples of the transparent support include resin films of ether ketone, polysulfone, polyether sulfone, polyimide, and polyetherimide, and further, a resin film obtained by laminating two or more layers of the resin. In the present invention, the transparent support is a support capable of transmitting light of the wavelength of the exposure light source, and is preferably stretched into a film and heat-set in terms of dimensional stability, and does not impair the effects of the present invention. Fillers such as titanium oxide, zinc oxide, barium sulfate, and calcium carbonate may be added within the range, and when used for medical purposes, a dye may be added for coloring blue. The thickness of the transparent support is about 10 to 500 μm, preferably 25 to 250 μm.

The support of the present invention is modified using a known surface modification technique such as corona discharge treatment and anchor coat treatment in order to improve the adhesiveness and coatability within a range not to impair the effects of the present invention. The backing layer may have a layer such as a back coat layer for preventing static electricity, preventing scratches, transporting properties, and preventing a plurality of sheets from being fed. When an anchor coat or a back coat layer is provided, the thickness is preferably about 0.001 to 10 μm, more preferably 0.005 to 5 μm.

In the following, in the present invention, the layers including the overcoat layer, the colorant layer, the anchor coat layer, etc. on the image forming side are collectively referred to as an image forming layer.

In the image forming layer, a light-to-heat conversion layer and a colorant layer may be laminated, and a plurality of each may be provided.
Further, the colorant layer may also serve as the light-to-heat conversion layer. It is characterized in that acicular ferromagnetic powder (A) and spherical ferromagnetic powder (B) are used as the coloring agent contained in the image forming layer.

The acicular shape in the ferromagnetic powder (A) means that the ratio of the major axis length to the minor axis length of the powder is 2.0 or more, preferably 2.0 or more and 20.0 or less.

[0014] Such ferromagnetic metal powders include Fe,
Co, Fe-Al system, Fe-Al-Ni system, Fe
-Al-Zn system, Fe-Al-Co system, Fe-Al-C
a-based, Fe-Ni-based, Fe-Ni-Al-based, Fe-Ni
-Co system, Fe-Ni-Zn system, Fe-Ni-Mn system,
Fe-Ni-Si system, Fe-Ni-Si-Al-Mn
System, Fe-Ni-Si-Al-Zn system, Fe-Ni-S
i-Al-Co system, Fe-Al-Si system, Fe-Al-
Zn-based, Fe-Co-Ni-P-based, Fe-Co-Al-
Ferromagnetic metal powders such as Ca-based and Fe-based metal magnetic powders can be used. The present invention is characterized by using such Fe-based metal powder.

From the viewpoint of corrosion resistance and dispersibility, F
Among the e-based metal powders, Fe-Al-based, Fe-Al-Ca
System, Fe-Al-Ni system, Fe-Al-Zn system, Fe-
Al-Co system, Fe-Ni-Si-Al-Co system, Fe
-Fe-Al based ferromagnetic powder such as -Co-Al-Ca based is preferable, and among these, Fe contained in the ferromagnetic powder is preferable.
The content ratio between the atoms and the Al atoms is expressed as Fe: Al =
100: 1 to 100: 20 and the ferromagnetic powder E
Analysis depth of 10 by SCA (X-ray photoelectron spectroscopy)
The content ratio between Fe atoms and Al atoms existing in the surface region of 0 ° or less is expressed as Fe: Al = 30: 70 to 70: 3 in atomic ratio.
0, or Fe, Ni, Al, and Si atoms, and at least one of Co and Ca atoms are contained in the ferromagnetic powder, and the content of Fe atoms is 90 atomic% or more; Ni atom content is 1 to 10 atomic%, Al atom content is 0.1 to 5 atomic%, Si atom content is 0.1 to 5 atomic%, Co atom or Ca atom content (both And Fe atoms and Ni atoms present in a surface area of 100 ° or less at an analysis depth of the ferromagnetic powder by ESCA (X-ray photoelectron spectroscopy) of 0.1 to 13 atomic%. , Al atoms, Si atoms, and C
The content ratio of o atoms and / or Ca atoms is F
e: Ni: Al: Si: (Co and / or Ca) = 10
0: (4 or less): (10 to 60): (10 to 70):
Those having a structure of (20 to 80) are preferable.

The ferromagnetic powder (A) has a major axis diameter of 0.30 μm or less, preferably 0.20 μm or less.

The spherical shape in the ferromagnetic powder (B) means that the ratio of the major axis length to the minor axis length of the powder is less than 1.5. If the axial ratio is less than 1.5, the powder becomes round. Or square.

As the ferromagnetic powder (B), γ-Fe
FeOx with ₂ O ₃ , Fe ₃ O ₄ or their intermediate iron oxide
(1.33 <x <1.50), for example, Co-containing γ-Fe ₂ O ₃ , Co-coated γ-Fe ₂ O ₃ , Co-containing Fe ₃ O ₄ , and Co-coated Fe ₃ O ₄ , Co-containing magnetic FeOx
(4/3 <x <3/2) Cobalt-containing iron oxide-based magnetic powder such as powder.

The shape of the ferromagnetic powder (B), whether spherical or amorphous, has a particle diameter of 0.40 μm or less, preferably 0.1 μm or less.
It is preferably 30 μm or less, and the ratio of the major axis of the particles in the powder (A) and the powder (B) is preferably (B)> (A).

By using such a ferromagnetic powder, the sensitivity of the ablation portion can be increased, and not only an image having a small residual ratio of the coloring agent can be obtained, but also the surface property of the image forming layer is improved. The content of the colorant contained in the colorant layer is about 10 to 99% by weight of the components forming the colorant layer,
Preferably it is 30 to 95% by weight.

As the binder, any resin can be used without particular limitation as long as it is a resin that can sufficiently hold the coloring material.

Representative examples of such binder resins include vinyl chloride resins such as polyurethane, polyester, and vinyl chloride copolymers. These resins include -SO ₃ M, -OSO ₃ M, and -SO ₃ M. COOM and -PO (OM
₁ ) ₂ [where M is a hydrogen atom or an alkali metal, M ₁
Represents a hydrogen atom, an alkali metal or an alkyl group. ] It is preferable to include a repeating unit having at least one type of polar group selected from the above], and the dispersibility of the magnetic powder can be improved by using a resin into which such a polar group is introduced. Incidentally, the content ratio of this polar group in each resin is about 0.1 to 8.0 mol%, preferably 0.2 to 6.0 mol%.
0 mol%.

The binder resin may be used alone or in combination of two or more kinds. When two or more kinds are used in combination, for example, the ratio of polyurethane and / or polyester to vinyl chloride resin is 90:10. 10:90, preferably 70:30 to 30:70.

Examples of the polar group-containing vinyl chloride include, for example,
Vinyl chloride - a resin having a vinyl alcohol copolymer _{hydroxyl, Cl-CH 2 CH 2 SO} 3 M, Cl-CH 2 CH
_{2 OSO 3 M, Cl-CH} 2 C0 2 M, Cl-CH 2 P (=
O) It can be synthesized by an addition reaction with a compound having a polar group such as (OM ₁ ) ₂ and a chlorine atom. One example is shown below.

-CH ₂ C (OH) H- + Cl-CH ₂
CH ₂ SO ₃ Na → —CH ₂ C (OCH ₂ CH ₂ SO ₃ N
a) H-Polar group-containing vinyl chloride resin is prepared by charging a predetermined amount of a reactive monomer having an unsaturated bond into which a repeating unit containing a polar group is introduced into a reaction vessel such as an autoclave, and adding benzoyl peroxide and azobisisobutyrate. General radical polymerization initiator such as lonitrile, redox polymerization initiator,
It can be obtained by polymerization using a cationic polymerization initiator or the like. Specific examples of the reactive monomer for introducing sulfonic acid or a salt thereof include vinyl sulfonic acid, allyl sulfonic acid, methacryl sulfonic acid, p- Examples include unsaturated hydrocarbon sulfonic acids such as styrene sulfonic acid and salts thereof. When a carboxylic acid or a salt thereof is introduced, for example, (meth) acrylic acid or maleic acid is used, and when a phosphoric acid or a salt thereof is introduced, (meth) acryl-2-phosphate may be used.

Further, in order to improve the thermal stability of the binder resin, it is preferable to introduce an epoxy group into the vinyl chloride copolymer. In this case, the content of the repeating unit having an epoxy group in the copolymer is about 1 to 30 mol%, preferably 1 to 20 mol%, and glycidyl acrylate or the like is used as a monomer for introducing an epoxy group. be able to.

The polyester having a polar group can be synthesized by a dehydration condensation reaction between a polyol and a polybasic acid partially having a polar group. Examples of the polybasic acid having a polar group include 5-sulfoisophthalic acid, -Sulfoisophthalic acid, 4-sulfoisophthalic acid, 3-sulfophthalic acid, 5
-Dialkyl sulfoisophthalate, dialkyl 2-sulfoisophthalate, dialkyl 4-sulfoisophthalate,
Examples thereof include dialkyl 3-sulfophthalates and alkali metal salts thereof. Examples of the polyol include trimethylolpropane, hexanetriol, glycerin, trimethylolethane, neopentyl glycol, pentaerythritol, ethylene glycol, propylene glycol, and 1,3-butane. Examples thereof include diol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, and cyclohexanedimethanol.

The polyurethane having a polar group can be synthesized by reacting a polyol with a polyisocyanate. Specifically, a polyurethane obtained by reacting a polyol with a polybasic acid partially having a polar group as the polyol is obtained. It is synthesized by using the obtained polyester polyol as a raw material. Examples of the polyisocyanate include diphenylmethane-4,4'-diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,5-naphthalene diisocyanate, and lysine isocyanate methyl ester. As the other synthetic methods of the polyurethane having a polar _{group, Cl-CH 2 CH 2 SO} 3 M with polyurethane and polar group and a chlorine atom with a hydroxyl group, Cl-CH ₂ CH
_{2 OSO 3 M, Cl-CH} 2 C0 2 M, Cl-CH 2 P (=
An addition reaction with a compound such as O) (OM ₁ ) ₂ is also effective.

Other binder resins include vinyl chloride resins such as vinyl chloride-vinyl acetate copolymer, polyolefin resins such as butadiene-acrylonitrile copolymer, polyvinyl acetal resins such as polyvinyl butyral, and celluloses such as nitrocellulose. Resin, styrene resin such as styrene-butadiene copolymer, acrylic resin such as polymethyl methacrylate, polyamide,
A phenol resin, an epoxy resin, a phenoxy resin, or the like may be used in combination, but when these are used in combination, the content is preferably 20% by weight or less of the total binder resin.

The coating solution for forming an image forming layer containing the above-mentioned colorant is applied on a transparent support, and then cured. As the curing agent, an isocyanate-based curing agent mainly containing isocyanate is used. Curing can be performed by a conventionally known curing method such as thermal curing, active energy curing, and moisture curing. To sufficiently perform curing, the image forming layer is cured by thermal curing and / or active energy ray curing. It is preferred that Examples of the aromatic isocyanate include tolylene diisocyanate (TDI), 4,4'-
Diphenylmethane diisocyanate (MDI), xylene diisocyanate (XDI), naphthylene diisocyanate (NDI) and the like can be used. As the thermosetting binder resin used for the thermosetting described above, and a curing agent added as necessary, a binder resin having a hydroxyl group, a carboxyl group or a sulfonic acid group and a curing agent having an isocyanate group, containing an epoxy group are included. A binder resin or a curing agent, an amino group-containing binder resin or a curing agent or a binder resin containing an acid anhydride or a curing agent, and the like.A resin that can be thermoset using a catalyst or the like may be appropriately selected. Can be used.

The content of the binder resin contained in the image forming layer is about 1 to 90% by weight of the components for forming the image forming layer.
Preferably it is 5-70% by weight. The curing agent or catalyst is used in an amount of usually 0.1 to 200 parts by weight, more preferably 0.5 to 1 part by weight, per 100 parts by weight of the thermosetting binder resin.
It is preferred to add and mix in a range of 00 parts by weight.

In the active energy ray curing, a combination of a conventionally known compound having an ethylenically unsaturated double bond or a compound having an epoxy group with a polymerization initiator can be used. The image forming layer may contain additives such as a lubricant, a durability improver, a dispersant, and an antistatic agent, in addition to the above components, as long as the effects of the present invention are not impaired.

Examples of the lubricant include fatty acid, fatty acid ester, fatty acid amide, (modified) silicone oil, (modified) silicone resin, and carbon fluoride, and examples of the durability improver include polyisocyanate. Can be. Examples of the dispersant include fatty acids having 12 to 18 carbon atoms, such as lauric acid and stearic acid, and amides, alkali metal salts, and alkaline earth metal salts thereof; polyalkylene oxide alkyl phosphates, lecithin, trialkyl polyolefinoxy Quaternary ammonium salts;
Examples include an azo compound having a carboxyl group and a sulfone group. In the above-described thermosetting binder resin, active energy ray-curable compound or binder resin, -SO ₃ M, -OSO ₃ M , -COOM and -PO (OM ₁ ) ₂ wherein M represents a hydrogen atom or an alkali metal, and M ₁ represents a hydrogen atom, an alkali metal or an alkyl group. Can also be used as a dispersant for improving dispersibility.

Examples of the antistatic agent include cationic surfactants, anionic surfactants, nonionic surfactants, polymer antistatic agents, conductive fine particles, and the like. , P. And the compounds described in 875-876 and the like.

In the present invention, an overcoat layer mainly composed of a resin binder may be provided. This binder resin can be used without any particular limitation as long as it can sufficiently hold the fine particles. In particular,
Polyurethane, polyester, vinyl chloride resin such as vinyl chloride copolymer, vinyl chloride resin such as vinyl chloride-vinyl acetate copolymer, polyolefin resin such as butadiene-acrylonitrile copolymer, polyvinyl acetal such as polyvinyl butyral Resin, cellulose resin such as nitrocellulose, styrene resin such as styrene-butadiene copolymer, acrylic resin such as polymethyl methacrylate, polyamide, phenol resin, epoxy resin, phenoxy resin, polyvinyl butyral, polyvinyl acetoacetal, Examples include acetal resins such as polyvinyl formal, and water-soluble resins such as polyvinyl alcohol and gelatin. The binder resin may be used alone or in combination of two or more.

In order to enhance the durability of the overcoat layer, it is preferable to add a curing agent such as polyisocyanate.

In the image forming step, the overcoat layer is imagewise exposed by irradiating it with heat energy imagewise.
Ablation occurs in the exposed portion of the colorant layer, and when the unnecessary colorant layer is transferred onto the transfer sheet, the overcoat layer on the exposed portion of the colorant layer is transferred onto the transfer sheet together. .

The above image forming layer includes, for example, a colorant, a binder resin, and if necessary, a durability improver, a dispersant,
A coating is prepared by kneading an antistatic agent, a filler, a filler, a curing agent, and the like with a solvent, and then the coating is diluted, coated on a support, and dried to form a coating.

As the solvent, alcohols (ethanol, propanol, etc.), cellosolves (methyl cellosolve, ethyl cellosolve), aromatics (toluene, xylene, chlorobenzene, etc.), ketones (acetone, methyl ethyl ketone, etc.), ester-based Use of solvents (such as ethyl acetate and butyl acetate), ethers (such as tetrahydrofuran and dioxane), halogen solvents (such as chloroform and dichlorobenzene), and amide solvents (such as dimethylformamide and N-methylpyrrolidone). Can be. Further, for kneading and dispersing the components of the image forming layer, a two-roll mill, a three-roll mill, a ball mill, a pebble mill, a cobol mill, a tron mill, a sand mill, a sand grinder,
Sqegvari Attritor, High Speed Impeller Disperser, High Speed Stone Mill, High Speed Impact Mill, Disper,
A high-speed mixer, a homogenizer, an ultrasonic disperser, a Henschel mixer, an open kneader, a pressure kneader, a continuous kneader, and the like can be used.

The formation of the image forming layer on the support is performed, for example, by coating and drying with an extrusion-type extrusion coater. If necessary, the magnetic powder may be subjected to a calendering treatment in order to make the orientation thereof uniform or to make the surface properties of the image forming layer uniform. In particular, in order to obtain a high-resolution image, it is preferable to orient the magnetic powder because the cohesive force in the layer can be easily controlled.

When the image forming layer is composed of a plurality of layers,
The coating and drying may be repeated for each layer, or may be performed by multi-layer coating by a wet-on-wet method and dried. In that case, it can be applied by a combination of a reverse roll, a gravure roll, an air doctor coater, a blade coater, an air knife coater, a squeeze coater, an impregnation coater, a bar coater, a transfer roll coater, a kiss coater, a cast coater or a spray coater and an extrusion coater. it can.

In the multi-layer coating in the wet-on-wet system, the upper layer is coated while the lower layer is kept wet, so that the adhesion between the upper and lower layers is improved.

In the present invention, the surface of the image forming layer is preferably subjected to a calendering treatment.

The calendering treatment means that after an image forming layer is laminated on a support, a temperature and a pressure are applied between a nip roller having high smoothness and a heatable nip roller and a roller facing the nip roller, usually having a diameter of 1 cm to 100 cm. By processing
This is a step of reducing the voids of the image forming layer generated in the steps of applying and drying the image forming layer coating solution, and increasing the density of the image forming layer itself.

The conditions for the calendering treatment are as follows. In order to reduce the porosity of the image forming layer, the linear pressure is usually 5
~ 500 kg / cm, preferably 10-400 kg / c
It is preferable to apply a nip pressure of m. The heating temperature is usually 40 ° C to 200 ° C, preferably 50 ° C.
Although it is from 120 ° C. to 120 ° C., the optimum heating temperature varies depending on the conveying speed, so that the maximum instantaneous temperature at which the temperature of the image forming layer rises during the calendering process is usually set from about 30 ° C. to about 100 ° C. When the linear pressure and the heating temperature of the calendering treatment are lower than the above ranges, the effects aimed at by the present invention are small, and when the linear pressure and the heating temperature are high, defects such as deformation, cracks and the like may occur in the support of the image forming material and the image forming layer itself. Is not preferred.

The calendering treatment is preferably carried out immediately after the application of the image forming layer regardless of the presence or absence of the curing treatment of the image forming layer. However, if necessary, the calendering treatment may be carried out after coating and laminating up to the overcoat layer.

In an image forming method to be described later, a transfer sheet provided for receiving an image after peeling after image exposure is formed by forming a layer with a resin having a self-supporting property or a resin film used as the support. Is used as a transfer sheet support, and a layer containing a thermoplastic resin is laminated thereon.

In the present invention, a method of forming an image after laser exposure by adhering a transfer sheet for receiving the ablated image forming layer without adhering the transfer receiving sheet to the image forming layer (hereinafter referred to as a two-sheet type), The sheet to be transferred is bonded to the image forming layer and supplied in two forms: an integrated image forming sheet (hereinafter referred to as an integrated type). The two-sheet type and the integrated type can be properly used depending on the application.

As the transfer sheet used in the present invention, a commercially available adhesive sheet, heat seal material or laminate material can be used as it is, or a sheet provided with an adhesive layer described later can be used as the transfer sheet. You can also.

When the transfer sheet is brought into contact with the colorant layer or overcoat layer of the image forming material, if the transfer sheet is a self-supporting resin, the transfer sheet formation resin is dissolved in a solvent to be colored. It can be provided by coating and drying like the agent layer. In addition, when a resin film such as that used for a support is used as a sheet to be transferred, if the film has heat sealing properties such as polypropylene, a colorant layer surface and a film are laminated and a heat roll or hot stamp is used. By subjecting the sheet to heat and pressure treatment, a sheet to be transferred can be obtained.

When a film having no heat sealing property is used, an adhesive layer is provided on the colorant layer (image forming layer) and the films are laminated. That is, the adhesive layer-forming composition is applied and dried on the colorant layer to laminate the resin film, or the adhesive layer-forming composition is applied and dried on the resin film, or the adhesive layer-forming composition is heated and melted, and extruded. After the lamination, the surface of the adhesive layer is superimposed on the colorant layer, and bonded by heat / pressure treatment using a heat roll or a hot stamp to provide a transfer-receiving sheet.

In the case where the image forming material and the sheet to be transferred face each other and are subjected to pressure or heat / pressure treatment, the pressure or heat / pressure treatment can be performed without increasing air bubbles and the like. If it is pressurized, a pressure roll or a stamper can be used, and if heat and pressure treatment is performed, a thermal head, a heat roll, a hot stamp, or the like can be used.

When a pressure roll is used, the pressure is usually preferably 0.1 to 20 kg / cm, more preferably 0.5 to 10 kg / cm, and the transfer speed is usually 0.1 to 100 mm / sec. Preferably, the pressure is more preferably 0.5 to 50 mm / sec, and the pressure when using a stamper is usually 0.05 to 10 kg / c.
m ² is preferred, and more preferably 0.5 to 5 kg / c.
m ² , and the pressurization time is usually preferably 0.1 to 50 seconds,
More preferably, it is 0.5 to 20 seconds. When using a heat roll, the heating temperature is usually preferably from 60 to 200 ° C, more preferably from 80 to 180 ° C, and the pressure is usually preferably from 0.1 to 20 kg / cm, more preferably from 0.5 to 20 kg / cm. -10 kg / cm, and the conveying speed is usually preferably 0.1-100 mm / sec, more preferably 0.5-50 mm / sec, and the heating temperature when using a hot stamp is:
Usually, the temperature is preferably from 60 to 200 ° C, more preferably from 80 to 200 ° C.
To 150 ° C., and the pressure is usually 0.05
It is preferably from 10 to 10 kg / cm ² , more preferably from 0.1 to 0.1 kg / cm ² .
5-5 kg / cm ² , and the heating time is usually 0.1-5
0 second is preferable, and more preferably 0.5 to 20 seconds.

(The heat treatment is performed at room temperature to about 180 ° C. with a heat roll, preferably at 30 to 160 ° C. for 0.1 hour.
About 20 kg / cm, preferably 0.5 to 10 kg / cm
1 to 500 mm / sec at a pressure of 5 cm, preferably 5 to 30 mm / sec.
This is performed while conveying at a speed of 0 mm / sec. The hardness of the rubber used for the roller is 40 to 90 degrees (JIS-6301A).
Type). When using a hot stamp, room temperature to 1
About 80 ° C., preferably 0.05 to 1 at 30 to 150 ° C.
About 0 kg / cm ² , preferably 0.5 to ⁵ kg / cm ²
At a pressure of about 0.1 to 50 seconds, preferably 0.5 to 20 seconds.
Heat for 2 seconds. ) The thickness of the sheet to be transferred is 5 to 300 μm.
m, more preferably 10 to 100 μm.

Examples of the method of peeling include a peeling plate, a method of fixing a peeling angle by a peeling roll, a hand peeling method of peeling off a transfer receiving sheet and an image forming material without fixing them by hand, and the like.
Various peeling methods can be used as long as they do not affect image formation.

The adhesive layer may be formed of any of those having adhesiveness or tackiness at room temperature, and those exhibiting adhesiveness or tackiness by applying heat or pressure.
For example, it can be formed by appropriately selecting a resin having a low softening point, an adhesion-imparting agent, and a thermal solvent.

Examples of the resin having a low softening point include ethylene copolymers such as ethylene-vinyl acetate and ethylene-ethyl acrylate; polystyrene resins such as styrene-butadiene, styrene-isoprene and styrene-ethylene-butylene; polyester resins; Polyolefin resins such as polyethylene and polypropylene; polyvinyl ether resins; acrylic resins such as polybutyl methacrylate;
Ionomer resins; cellulosic resins; epoxy resins; vinyl chloride resins such as vinyl chloride-vinyl acetate copolymers, and the like. Examples of the adhesion-imparting agent include rosin, hydrogenated rosin, rosin maleic acid, polymerized rosin and Unmodified or modified products such as rosin phenol, terpenes, petroleum resins and modified products thereof, and the like. Examples of the heat solvent include compounds which are solid at ordinary temperature and which reversibly liquefy or soften when heated, and specifically, terpineol, menthol, acetamide, benzamide, coumarin, benzyl cinnamate, diphenyl ether, crown ether, Monomolecular compounds such as camphor, p-methylacetophenone, vanillin, dimethoxybenzaldehyde, p-benzylbifevir, stilbene, margaric acid, eicosanol, cetyl palmitate, stearamide, behenylamine, beeswax, candelilla wax, paraffin wax , Ester wax, montan wax, carnauba wax, amide wax, polyethylene wax, microcrystalline wax and other waxes, ester gum, rosin maleic resin, rosin pheno Rosin derivatives such as Le resin, phenol resin,
Ketone resin, epoxy resin, diallyl phthalate resin,
Examples include terpene hydrocarbon resins, cyclopentadiene resins, polyolefin resins, polycaprolactone resins, and high molecular compounds represented by polyolefin oxides such as polyethylene glycol and polypropylene glycol.

The thickness of the adhesive layer is about 0.1 to 40 μm, preferably 0.3 to 30 μm, and the thickness of the whole transfer receiving sheet including the support is about 0.1 to 200 μm, preferably 0.5 to 200 μm. 100 μm.

The coating solution is prepared by dispersing or dissolving the components to be formed in a solvent, and the solvent used in the coating method of coating and drying this coating solution is water, alcohols (eg, ethanol, propanol), cellosolves (eg, Methyl cellosolve, ethyl cellosolve), aromatics (eg, toluene, xylene, chlorobenzene), ketones (eg, acetone, methyl ethyl ketone), ester solvents (eg, ethyl acetate, butyl acetate, etc.), ethers (eg, tetrahydrofuran, dioxane) , Chlorinated solvents (eg, chloroform, trichloroethylene), amide solvents (eg, dimethylformamide, N-methylpyrrolidone), dimethylsulfoxide, and the like. Alternatively, a layer can be formed by melting a forming component with a hot melt and extruding.

Using the above-described image forming material in which a colorant layer is laminated on a support, a transfer-receiving sheet is brought into intimate contact with the colorant layer surface before exposure, and image-exposed to the exposed portion of the colorant layer. After the ablation occurs, the transfer sheet is peeled off, and only the ablated portion of the colorant layer is transferred to the transfer sheet side to form an image.

The image exposure can be used without any particular limitation as long as it is a light source that causes ablation. However, in order to obtain high resolution, an electromagnetic wave whose energy application area can be narrowed down, in particular, ultraviolet light having a wavelength of 1 nm to 1 mm, visible light , Infrared rays are preferred, and light sources that can apply such light energy include lasers, light-emitting diodes, xenon flash lamps, halogen lamps, carbon arc lamps,
Examples include a metal halide lamp, a tungsten lamp, a quartz mercury lamp, a high-pressure mercury lamp, and the like. At this time, the energy to be applied can appropriately select an exposure distance, time, and intensity depending on the type of the image forming material.

When a laser beam is used as a light source, a wavelength of 60 is required for efficient ablation.
It is preferable in terms of sensitivity to use a laser in the range from visible light of 0 to 1200 nm to a near infrared region since light energy can be efficiently converted to heat energy.

For the purpose of efficiently removing the unnecessary colorant layer which has been ablated in the exposed area, the image forming material and the sheet to be transferred are faced to each other, and before or after exposure, pressure or heat / pressure treatment is performed. Then, the image quality is further improved.

[0064]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto. In the following, “parts” means “parts by weight as active ingredients” unless otherwise specified.

Example 1 The following composition was kneaded and dispersed using an open kneader on a transparent polyethylene terephthalate (PET) film (T-60, manufactured by Toray Industries Co., Ltd.) having a thickness of 100 μm and having one surface subjected to corona discharge treatment. After preparing a colorant layer coating solution containing a magnetic powder composed of a metal, applying the solution by extrusion coating, performing a magnetic field orientation treatment while the coating film is not dried, then drying, and then calendering the surface with a calender. Processing, then 6
Heat treated at 0 ° C for 72 hours to obtain a thickness of 0.8 μm
Were formed respectively.

<Colorant Layer Coating Solution 1> Powder (A): 100 parts of Fe—Al-based ferromagnetic powder (major axis diameter: 0.14 μm, BET: 53 m ² / g) Powder (B): γ-Fe ₂ O ₃ ferromagnetic powder 1 part (average particle size: 0.20 μm, BET: 30 m ² / g) Polyurethane resin 10 parts (Toyobo Co., Ltd., UR-8200) Polyester resin 5 parts (Toyobo Co., Ltd.) Dispersant: Toho Chemical Co., Ltd., Phosphanol RE-610 2 parts Isocyanate compound 4 parts (Nippon Polyurethane Industry Co., Ltd., Coronate HX) Cyclohexanone 100 parts Methyl ethyl ketone 100 parts Toluene 100 parts <Colorant layer Coating liquid 2> Same as coating liquid 1 except that powder (B) was changed to 5 parts.

<Colorant Layer Coating Solution 3> The same as the coating solution 1 except that the amount of the powder (B) was 10 parts.

<Coating solution 4 for colorant layer> The same as the coating solution 1 except that the amount of the powder (B) was 30 parts.

<Colorant Layer Coating Solution 5> The powder (B) was mixed with Fe ₃
Same as coating solution 3 except that O ₄ was used.

<Colorant Layer Coating Solution 6> The powder (B) was coated with Co-
Same as coating solution 3 except that γ-Fe ₂ O ₃ was used.

<Colorant Layer Coating Solution 7> The powder (B) was
Same as coating solution 3 except that Fe ₃ O ₄ was used.

<Colorant Layer Coating Liquid 8> The same as the coating liquid 3 except that the powder (A) had a major axis length of 0.08 μm.

<Colorant Layer Coating Liquid 9> The same as the coating liquid 3 except that the powder (A) had a major axis length of 0.19 μm.

<Colorant Layer Coating Solution 10>
The same as the coating liquid 3 except that the amount was 5 parts.

<Colorant Layer Coating Solution 11>
The same as the coating liquid 3 except for the parts.

<Colorant Layer Coating Solution 12> γ-Fe ₂ O ₃ is converted to α
Identical to the coating liquid 3 except for using the -fe ₂ O _3.

<Colorant Layer Coating Solution 13> γ-Fe ₂ O ₃
l ₂ O ₃ (Sumitomo Chemical Co., Ltd., HIT-60G), except that the same coating solution 3.

<Colorant Layer Coating Solution 14> γ-Fe ₂ O ₃ was converted to carbon black (Colombian Carbon Japan Co., Ltd.)
The same as the coating liquid 3 except that Raven MT-P BEADS was used.

<Coloring Layer Coating Solution 15> Same as Coating Solution 3 except that the powder (A) had a major axis length of 0.20 μm.

<Colorant Layer Coating Liquid 16> The same as the coating liquid 3 except that the powder (A) had a major axis length of 0.25 μm.

However, in each of the coating solutions, the ratio of the powder (A) and the powder (B) to the binder, so-called B / P, is 14.85%, which is the same as that of the coating solution 1.

Next, an overcoat layer coating solution composed of the following composition is prepared, and is coated and dried by wire bar coating so that the coating solution before drying is 10 g / m ² on the colorant layer surface. Thus, an overcoat layer having a coverage of 0.1 g / m ² was formed.

<Coating Solution for Overcoat Layer> Phenoxy resin (Phenoxy Associates: PKHH) 1 part Cyclohexanone 250 parts Toluene 749 parts As a transfer-receiving sheet, a transparent PET film (diafoil hoechst) having a thickness of 24 μm and having a 24 μm-thick surface that has been easily bonded Co., Ltd .: T-100E) Using a support, prepare an adhesive layer coating solution composed of the following composition, and apply a wire bar on the easy-adhesive surface of the support to a coating weight of 1.5 g / m 2 after drying. ^The resultant was coated and dried to obtain a transfer-receiving sheet.

<Coating solution for adhesive layer> Polyurethane resin 115 parts (Nippon Polyurethane Industry Co., Ltd .: Nipporan 3116, solid content 21%) Silicone fine particles 1 part (Toshiba Silicone Co., Ltd .: Tospearl 120) Cyclohexanone 24 parts Toluene 36 parts Methyl ethyl ketone 30 parts 《Evaluation of bar scratches》 On a substrate coated with a colorant layer,
The degree of scratching when the overcoat layer was applied on the colorant layer using a wire bar was evaluated in four stages. 2 or less shall be rejected.

4: 0 pieces 3: 1 piece 2: several pieces on a part of the coating surface 1: whole surface of the coating surface Next, a semiconductor laser (LT090, manufactured by Sharp Corporation)
(MD, main wavelength: 830 nm), the image was exposed by focusing on the surface of the image forming layer and performing scanning exposure from the support side. The release sheet of the image forming material was peeled off to form an image. The sensitivity, the resolution of the formed image, and the stain on the solid exposed portion were evaluated according to the following criteria.

<Sensitivity> 0.5 mm × 4 μm beam diameter
Solid scanning exposure such that a 0.5 mm image was formed was performed, and the average exposure amount (E: mJ / cm ² ) on the surface of the image forming material on which the image was formed was evaluated in four steps. 3: 100 ≦ E ≦ 250 2: 250 <E ≦ 400 1: 400 <E <Resolution> Scanning exposure is performed with a beam diameter of 4 μm and a scanning pitch of 4 μm.
The number (N) of confirmable lines per mm when an image was formed with the average exposure amount of the image forming material surface at m was evaluated on a four-point scale. 3 or less shall be rejected.

4: 125 = N 3: 120 ≦ N <125 2: 110 ≦ N <120 1: 110> N <Solid exposure portion contamination> 10 mm × 10 m at a beam diameter of 4 μm
After performing a solid scanning exposure of m and removing the release sheet, the visual density (OD) was measured with an optical densitometer (X-rite 310, manufactured by X-rite), the density of the support was subtracted, and the density of the support was subtracted. Was evaluated. 2 or less shall be rejected.

4: 0.001 ≧ OD 3: 0.005 ≧ OD> 0.0012: 0.010 ≧ OD> 0.0051 1: 0.030 ≧ OD> 0.010 The evaluation results are shown in Table 1. .

[0089]

[Table 1]

[0090]

According to the present invention, it is possible to obtain an image forming material which is hardly damaged during manufacturing, has a high sensitivity at the time of forming an image, and is not accompanied by deterioration of image quality in an image forming step.

Claims (4)

[Claims] 1. An image forming material comprising a support having thereon a colorant layer containing a needle-like ferromagnetic powder (A) and a spherical ferromagnetic powder (B) as a colorant. 2. The method according to claim 1, wherein the ratio of the powder (A) to the powder (B) is 1 part by weight or more and 30 parts by weight or less based on 100 parts by weight of the powder (A). The image forming material according to claim 1, 3. The method according to claim 1, wherein the main component of the powder (A) is Fe-based, and the main component of the powder (B) is γ-Fe ₂ O ₃ or Co-containing iron oxide. The image forming material as described in the above. 4. The image forming material according to claim 3, wherein the ratio of the major axis length of the particles in the powder (A) and the powder (B) is (B)> (A).