JPS6122338A - Light and heat sensitive type dry film and image forming method by using it - Google Patents

Abstract

PURPOSE:To enable an image high in resolution to be formed by forming a photoresist (PR) layer on one side of a plastic film (PR) base, further on this layer, a PF protective layer, and a heat sensitive layer essentially consiting of a heat sensitive polymer on the other side. CONSTITUTION:The PR layer and the plastic protective layer is formed in succession on one side of PF base, and the heat sensitive layer essentially consisting of a heat sensitive polymer to be lowered in water solubility with a light and heat convertible substance and heat is formed on the other side of th PF base. After the protective film is peeled, the face of th PR layer is brought into close contact with a resist image-forming substrate, they are imagewise exposed to laser beams incident from the side of a dry film (DF) to produce the difference of water solubility between the exposed and unexposed areas of the heat sensitive layer and the unexposed areas are removed by dissolving them in water. This layer is used as a mask and the PR layer is exposed to light of the wavelength region to which the PR layer is sensitive, uniformly incident from the DF side, to produce solubility difference between the exposed and unexposed areas, the exposed areas of the PR layer are selectively dissolved, and after the solubility difference of the film base is also produced, it is developed to dissolve off the exposed or unexposed areas of the PR layer together with the film base, resulting in leaving the undissolved unexposed or exposed areas of the PR layer on the substrate as a resist image.

Description

[Detailed description of the invention]

TECHNICAL FIELD The present invention relates to a light- and heat-sensitive dry film for forming a resist image using heat mode Tyzo laser light and ultraviolet light, and an image forming method using the same. Conventional technology Printed wiring board (copper-clad laminate), metal plate chemical etching processing, photoelectro 7 ohming processing,
Conventionally, dry films for forming resist images on substrates that require resist images, such as those related to markings and displays, have been provided with a photoresist layer on a plastic film support, and then covered with a plastic film as a protective film. is used. To directly form a resist image on the substrate using a laser beam using this type of dry film, generally first, the protective film of the dry film is peeled off, and then the photoresist layer surface is brought into close contact with the substrate surface. The photoresist layer in the exposed area is subjected to imagewise exposure to ultraviolet laser light from the side, causing a photoreaction (crosslinking hardening or decomposition), thereby creating a difference in solubility in the developer between the exposed area and the non-exposed area of the photoresist layer. After the formation, the support film is peeled off (without peeling off if the support film is soluble in a developer), and then developed with a developer to selectively remove the exposed or non-exposed areas. This is done by dissolving and removing in a developer (if the support film is soluble in the developer, this film is also dissolved and removed at the same time). However, although conventional dry films have the advantage of being excellent in chemical resistance and being able to form high-resolution images, since image formation using laser light uses ultraviolet laser light, This method requires a high-output W laser, making the device large and expensive. Purpose The purpose of the present invention is to combine a normal ultraviolet-sensitive photoresist layer with a heat-sensitive layer that is sensitive to mW-7-doped type laser light, thereby eliminating the need for a high-power laser and providing chemical resistance. It is an object of the present invention to provide a photosensitive and thermal dry film capable of forming an excellent high-resolution MS and an image forming method using this dry film. Structure: The photosensitive and thermosensitive dry film of the present invention has a photoresist layer on one side of a plastic film support, and further covers the photoresist layer with a plastic film to serve as a protective film.
On the other side, there is a heat-sensitive layer mainly composed of (a) a photothermal converting material that absorbs light and converts it into heat, and (b) a heat-sensitive polymer material whose solubility or redispersibility in water is reduced by heat. It is characterized by one feature. The image forming method of the present invention can be divided into the following two types depending on the type of photoresist. One method is to peel off the protective layer of the dry film, then bring the photoresist layer side into close contact with the substrate on which the resist image is to be formed, and expose the heat-mode type laser beam imagewise from the heat-sensitive layer side. After creating a difference in water solubility or redispersibility between the exposed and non-exposed areas of the heat-sensitive layer, the non-exposed areas of the heat-sensitive layer are selectively dissolved or re-dispersed in water by development with water. Then, using the exposed portion of the undissolved or unredispersed residual heat-sensitive layer as a mask, the entire surface of the photoresist layer is exposed to light in the photosensitive wavelength range from the heat-sensitive layer side to form a gap between the exposed portion and the non-fogged portion of the photoresist layer. After creating a solubility difference in a developer that selectively dissolves the exposed or non-exposed areas of the photoresist layer, the support film is peeled off and developed with the developer to remove the exposed areas of the photoresist layer. Alternatively, the non-exposed portions are selectively dissolved and removed in the developer, thereby leaving the undissolved non-exposed portions or exposed portions of the photoresist layer as a resist image on the substrate, and others. One method is to peel off the retention film of the dry film, then bring the photoresist layer surface into close contact with the substrate on which the resist image is to be formed, and imagewise expose it to a heat mode type laser beam from the heat-sensitive layer side. After creating a difference in water solubility or redispersibility between the exposed and non-exposed areas of the heat-sensitive layer, the non-exposed areas of the heat-sensitive layer are selectively dissolved and removed by water development, and then Using the exposed portion of the undissolved or unredispersed remaining heat-sensitive layer as a mask, the entire surface is exposed from the heat-sensitive layer side to light in the photoresist layer's photosensitive wavelength range to form a photoresist between the exposed portion and the non-exposed portion of the photoresist layer. After creating a solubility difference in a developer that selectively dissolves the exposed or unexposed areas of the layer and dissolves the support film, the exposed or unexposed areas of the photoresist layer are supported by development with the developer. The photoresist layer is selectively dissolved and removed together with the photoresist film in the developing solution, thereby leaving undissolved non-exposed or exposed areas of the photoresist layer on the substrate as a resist image. To explain the materials used in the plate-making material of the present invention, first, the photoresists used for the photoresist layer may be those commonly used in the past, such as compositions consisting of +11, (21 and (, 3) below). or (1
) and (4). (1) Binder resin: Methyl methacrylate β-hydroxyethyl acrylate copolymer, Methyl methacrylate β-hydroxyethyl methacrylate copolymer, Acrylic acid - β-hydroxyethyl acrylate copolymer, Methyl methacrylate Tolbutyl methacrylate copolymer, (2) Photopolymerizable monomer or oligomer; ethylene glycol diacrylate or dimethacrylate, triethylene glycol diacrylate or dimethacrylate, trimethylolpropane triacrylate or trimethacrylate, pentaerythritol triacrylate or trimethacrylate, Tetraethylene glycol diacrylate or dimethacrylate, 2-hydroxyethyl methacrylate, etc. (3) Photopolymerization initiator; benzoin, benzoin ether, benzophenone, benzyl, anthraquinones, thioxanthone, etc. (4) Photopolymerizable condensate: Condensate of 0-naphthoquinonediazide sulfonic acid chloride and amines or phenols (Japanese Patent Publication No. 36-2206
Publication No. 2, Publication No. 37-1953, Publication No. 3B-15665, Publication No. 5゜-5082, Publication No. 5 J-13013
(described in U.S. Pat. No. 3,046,120, etc.). The weight ratio of each component in the composition as described above is (1) +
(2) In the case of a composition of ++31, the binder resin (1) is 10 to 70%, the photopolymerizable monomer or oligomer (2) is 50 to 80%, and the photopolymerization initiator (3) is 5 to 10%.
% is appropriate, and in the case of the composition (1) + (4), it is appropriate that the binder resin of (1) is 10 to 70% and the photopolymerizable condensate of (2) is 20 to 50%. . In addition to the above ingredients, the photoresist layer also contains hydroquinones, phenol derivatives, etc. as thermal polymerization initiators, benzotriazoles, etc. to improve adhesion to the substrate, etc.
Plasticizers such as thiazoles can be added to improve flexibility, and dyes can be added to make images easier to see. On the other hand, light (
Any substance that can absorb heat mode type laser light and convert it into heat can be used, such as carbon black, carbon graphite, phthalocyanine pigments, cyanine pigments, iron powder, graphite powder, iron oxide powder, lead oxide, In addition to inorganic or organic pigments such as silver oxide, chromium oxide, iron sulfide, and chromium sulfide, diamine metal complexes, dithiol metal complexes,
Mercazotophenol-based gold-striped complexes, aluminum salts (described in JP-A-58-16888;
-26293), etc. As a heat-sensitive polymer substance used in combination with these photothermal converting substances,

Examples include thermoplastic resin particles, thermocoagulable proteins, and water-soluble resins as shown below. Thermoplastic resin particles: Those with a minimum film forming temperature MFT of 50 to 150°C, such as polyvinyl acetate, polystyrene, polyvinyl chloride, polyvinylidene chloride, polypropylene, polyethylene, polyacrylic ester, polymethacrylic ester, ethylene-acetic acid Vinyl copolymer, vinyl chloride-vinyl acetate copolymer, styrene acrylic acid copolymer, novolac resin, linear? There are particles of polyester resin, ionomer resin, polyimbutylene, polyisoprene, polybutadiene, styrene-butadiene copolymer, chlorinated polyethylene, chlorinated polypropylene, and the like. Thermocoagulable proteins; albumin, hemoglobin, globulin, promilan,
Single proteins such as glutelin, dried egg white whose main component is albumin, and soybean protein whose main component is hemoglobin (
Alkylation of protein-containing substances such as dried soy milk, concentrated soy protein powder), wheat gluten (active wheat protein) whose main ingredients are promilan and glutelin, and corn protein whose main ingredient is zolomilan, as well as the above-mentioned single proteins and protein-containing substances. , acylation, esterification, amidation, oxidation, reduction, and other chemical modifications. Water bath resin: Acrylic water-soluble polymers such as sodium polyacrylate, partially saponified products of polyacrylic acid ester, polyacrylamide, cellulose-based materials such as methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, hydroxyzorobyl cellulose, and ethyl hydroxyethyl cellulose. Water-soluble polymers, inbutylene water-soluble polymers such as isobutylene/maleic anhydride copolymer, and its esters or salts, styrene/maleic anhydride copolymer, styrene/crotonic acid copolymer, styrene/sulfone Styrene water-soluble polymers such as acid copolymers, vinylpyrrolidone water-soluble polymers such as polyvinyl bitetralidone, polyvinylpyrrolidone/vinyl acetate copolymers, polyvinyl methyl ether, vinyl methyl ether/maleic anhydride copolymers, Vinyl ether water-soluble polymers such as and their esters, vinyl acetate/maleic anhydride copolymers, vinyl acetate/crotonic acid copolymers,
Vinyl acetate/acrylic acid copolymer, vinyl alcohol/
Water-soluble vinyl acetate polymers such as maleic anhydride copolymers, alginic acid polymers such as alginic acid, propylene glycol alginate, ammonium alginate, and sodium alginate, polyethylene oxide, polypropylene oxide, polystyrene oxide, etc. These include ethylene-based polymers. Other examples include ammonium salts or amine salts of water-insoluble resins as shown below. Here, the water-insoluble resin is an unsaturated carboxylic acid copolymer such as acrylic acid, crotonic acid, methacrylic acid, incrotonic acid, maleic acid, fumaric acid, methylmaleic acid, methylfumaric acid, itaconic acid, etc. Copolymers of acids and copolymerizable monomers such as vinyl acetate, styrene, α-methylstyrene, acrylic esters, methacrylic esters, ethylene, propylene, butylene, isobutylene, vinyl chloride; resol type or novolak type phenolic resins; polyvinyl hydroxybenzoate; polyvinyl hydroxybenzal; cellulose acetate hydrogen 7-thale; polyhydroxystyrene; shellac; ossein; monomer-based copolymers containing sulfonic acid groups, such as styrene to p-)luenesulfonic acid copolymers,
Examples of the acrylic acid ester include p-toluenesulfonic acid copolymer. When these water-insoluble resins are used as ammonium salts or amine salts, they are usually prepared by mixing the resin with aqueous ammonia or amine in a heat-sensitive layer forming solution without isolating the resin as a salt. In the case of ammonium or amine salts of these water-insoluble resins, the property of ammonia or amine being volatilized by heat and returning to the original water-insoluble resin is utilized. The above heat-sensitive polymer substances may be used alone or in combination. The ratio of the heat-sensitive polymer material and the photo-PA converting material in the heat-sensitive layer is preferably about 1:0.1 to 0 (k amount). In addition, a water-soluble, alkali-soluble or organic solvent-soluble resin binder may be added to the heat-sensitive layer in an amount of up to about 90% by weight of the layer weight, if necessary. Examples of this type of binder include water-soluble or alkali-soluble ones such as gelatin, starch, polyvinyl alcohol, polyvinylpyrrolidone, methyl cellulose, hydroxyethyl cellulose, vinyl alcohol-maleic acid copolymer, vinyl acetate-crotonic acid copolymer, styrene-malein. Acid copolymers, etc., and those soluble in organic solvents include homopolymers or copolymers such as polyvinyl acetate, polystyrene, polypropylene, polyvinylidene chloride, polyethylene, and acrylic ester (these materials have a minimum film forming temperature of 50 ℃
It is used in the form of an emulsion. ) etc. In addition to the above-mentioned materials, other organic or inorganic pigments, dyes, and ultraviolet absorbers may be added to the heat-sensitive layer as necessary to further increase the optical density. ξ and other organic or inorganic pigments, dyes such as Luxol (registered trademark) Orange 2RX Color Index +2
5 (Solvent Orange), Luxor (Registered Trademark Name) Orange OS Color -] 7- Index φ24 (Solvent Orange), Luxor (Registered Trademark Name) Orange Color Index +20
(Solvent Orange), Plast (registered trademark name) Orange Color Indexna 21 (Solvent Orange), Plast (registered trademark name) Orange MS Cassie Index +22 (Solvent Orange), Grasol (registered trademark name) Fast Orange 2RX Color index -33 (solvent orange), oil orange color index φ12051) (solvent skewer yellow φ14), Sudan orange HA color index ≠12055 (solvent yellow φ14)
), Le/Sole Yellow (tlJ Large Index Φ
16 (Solvent Yellow), Luxor Y4-
T color index ÷ 47 (solvent yellow)
, Shirasto Yellow GR Color Index $39 (
Solvent Yellow), Plast Yellow MG8 Color Indexer 40 (Solvent Yellow), Oil Yellow 3G Color Indexer 29 (Solvent Yellow), Oil Yellow Color Indexer 2 (Solvent Yellow), Sudan Yellow Color index Φ30 (solvent yellow),
Luxor Fast Blue AR Color Index 37 (Nrubento Italian Flu), Luxor Tatami Fast Black L Color Index ÷ 17 (Solbento Flack), Brimrose Yellow Color Index +77603 (Pigment), Chrome Yellow
Light Color Index + 77603 (Pigment), Chrome Yellow Medium Color Index Na 77600 (Pigment), Toluidine Yellow GW Color Index ÷ 71680 (Pigment)
, Moripdate Orange Color Index ÷ 776
05 (Pigment), Dalamar Yellow Color Index Φ11741 (Pigment), Clean Gold Color Index + 12775 (Pigment), Graf d'Or Yellow Color Index Pigment Yellow ÷ 61, Graf d'Or Orange Color Index Pigment Orange + 13, etc. Can be mentioned. As a UV absorber, 2,2'-dihydroxy-4-
Methoxy-benzophenone, 4-dodecyloxy-2-
Hydroxybenzophenone, 44-dihydroxybenzophenone, hydroxyphenylbenzotriazole, 2
-(2'-hydroxy-51-methoxyphenyl)benzotriazole, resorcinol monobenzoate,
2-Hydroxy-4-methoxybenzophenone, 2.2
'-dihydroxy-4,4'-dimethoxy-benzophenone, 2.2', 4.4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxy-benzophenone-5-sulfonic acid, (sodium salt of oak and above) , ethyl-2-cyano-3,3-diphenylacrylate, 2-ethylhexyl-2-cyano-3,3-
1>Phenyl acrylate. Examples of the plastic film for the support include transparent films of polyester, polycarbonate, polyester, polycarbonate, polyethylene, I-lipropylene, I-resulfone, cellulose acetate, polyvinyl butyral, polystyrene, PvA, and the like. Thickness is 10
~100μ is preferable. Plastic films for protective membranes include polyethylene,
polypropylene,? Examples include non-breathable films such as lysobutylene and polyester. Thickness is 10-5
Approximately 0μ is appropriate. To make the dry film of the present invention, for example, a photoresist is coated on a plastic film support, and
A photoresist layer with a thickness of about 10 to 100 μm is formed by drying at a temperature of about 50°C, and then a plastic film is placed on top of it to form a protective film, and then a dispersion containing components for a heat-sensitive layer is formed on the opposite side. Apply a liquid (made by uniformly dispersing each component by stirring, ultrasonic dispersion, etc.) and leave it for 30 to 50 minutes.
A heat-sensitive layer having a thickness of about 1 to 10 μm may be formed by drying at a temperature of 1°C. Next, the image forming method using a dry film of the present invention will be explained. First, the protective film of the dry film is peeled off, and the exposed photoresist layer is brought into close contact with the substrate on which the image is to be formed, and when the dry film side is exposed to the laser beam of the Heat Mode Tyzo in an imagewise manner, that area becomes thermally sensitive. The photothermal converting material in the layer absorbs this light and generates heat,
Heats the coexisting heat-sensitive polymer material. The heat-sensitive polymer substance heated in this way decreases its water solubility or dispersibility due to thermal coagulation, thermal melting (or thermal fusion), deammonia (or deamine), etc., and as a result,
A difference in water solubility or redispersibility occurs between the exposed and non-exposed areas of the heat-sensitive layer. Therefore, if the heat-sensitive layer in such a state is then subjected to water development, the unexposed areas of the heat-sensitive layer containing the original heat-sensitive polymer material whose solubility or redispersibility in water will not change will change. Since it is easier to dissolve or redisperse in water than the exposed area containing a heat-sensitive polymer substance with reduced dispersibility, the non-base part of the heat-sensitive layer is selectively dissolved in water or dispersed and removed. Next, the remaining heat-sensitive layer exposed area t mask is used to illuminate the entire surface of the photoresist layer from the same dry film side with light in the photoresist layer's sensitive wavelength range (usually ultraviolet or near ultraviolet light). The photoresist in the resist layer is structurally cured or decomposed, so that between the exposed and non-exposed areas of the photoresist layer there is a photoresist cross-linked cured product or decomposition product, and thus the exposed area of the photoresist layer or the structure. photoresist before curing or decomposition;
Therefore, a difference in solubility with respect to a developer occurs, which selectively dissolves the non-exposed portions of the photoresist layer. (In this case, the photoresist layer in which exposed areas are selectively dissolved is called positive type, and the photoresist layer in which non-exposed areas are selectively dissolved is called negative type.) Therefore, next, the support film of the dry film is After peeling off, if the photoresist layer in this state is developed with a developer, the exposed areas will be selected if the photoresist layer is positive, and the non-exposed areas will be selected if the photoresist layer is negative. The photoresist layer is then dissolved and removed by the developing solution, and undissolved unexposed or exposed areas of the photoresist layer remain as a resist image on the substrate. Note that if a support film soluble in a developer is used as the support film of the dry film, the step of peeling off the support film can be omitted. That is, in this case, as mentioned above, develop after the entire surface has been turned off.
Thus, the support film is dissolved and removed in a developer together with the exposed or unexposed areas of the photoresist layer. Furthermore, in the image forming method of the present invention, before coating the dry film on the substrate, laser exposure and water development are performed, the protective film is peeled off, and then this dry film is closely attached to the substrate, and the following steps are performed as described above. The entire surface may be exposed and developed. Note that when making a printed wiring board, etching is performed after forming a resist image on the board as described above. In the above image forming method, the laser beam is H.
-N laser, semiconductor laser, YAG laser-,
Ar visible laser, CO laser, etc. can be used. A suitable beam diameter is about 1 to 50 microns. In order to further improve the solubility of the water used for developing the heat-sensitive layer, organic solvents such as alcohols and ketones, surfactants, etc. can be added depending on the material in the layer. On the other hand, as the developer used for developing the photoresist layer, depending on the material in the layer, water, the above-mentioned organic solvent, and a mixture thereof are used. acid,
Alkali, salts, surfactants, etc. can be added. As the developing method, shower development, Sosolet development, immersion development, Wizo development, etc. are adopted. The present invention will be explained below by way of examples. Note that all parts are parts by weight. Example 1 Methyl methacrylate β-hydroxyethyl 100 on one side of a 2.5μ thick polyester film support
parts acrylate (weight ratio 17:3) co-electrolyte tetraethylene glycol diacrylate 100 parts 2-ethylanthraquinone 15 parts p-methoxyphenol 3 parts methyl violet
0.2 parts methyl ethyl ketone
A solution consisting of 800 parts was applied and dried at 70 to 80°C to form a 25 μm thick photoresist layer, which was then cut out with a 20 μm thick polyethylene film to form a protective film. Meanwhile, carbon black 2 parts water
A mixture consisting of 20 parts was dispersed in a bowl for 5 hours, and this dispersion was applied to the opposite side of the polyester film.
A dry film was prepared by drying at 50° C. to form a heat-sensitive layer with a thickness of 2 μm. The protective film of this dry film is peeled off, and the 26-photoresist layer surface is brought into close contact with the copper foil surface of a copper-clad laminate for printed wiring (a board made by laminating copper foil on Bakelite), and an IW is output from the dry film side. Ar town vision laser beam Y 4 m with a beam diameter of 20 μm was fogged into a negative image at a scanning speed of 7 seconds. This was then immersed in Y water and developed by wiping the surface of the heat-sensitive layer with absorbent cotton. When the non-cured portion of the heat-sensitive layer was redispersed and removed in the water, a black negative image appeared on the photoresist layer. Further, after exposing the entire surface of this image surface to ultraviolet rays using a metal halide lamp with an output of 3 KW, the polyester film support was peeled off, and the photoresist layer surface was coated with 1.1. -) When the photoresist layer was immersed in trichloroethane and developed by wiping it with absorbent cotton, the non-extractable portions of the photoresist layer were dissolved and removed by the trichloroethane, leaving a sheer resist image on the substrate. Next, the copper foil surface of this substrate was etched with a 30° Baume aqueous solution of ferric chloride, and then the resist image was swollen and peeled off with methylene chloride to obtain a printed wiring board. On the other hand, for comparison, a dry film was prepared in the same manner except that the heat-sensitive layer was not provided, and after peeling off the protective film, the photoresist layer surface was closely attached to the copper foil surface of the steel-clad laminate.
From the dry film side, the negative film was used as an original and the metal halide lamp was used to irradiate it with ultraviolet rays, as follows.
A printed wiring board was prepared by developing, etching, and removing the resist image in the same manner. The printed wiring board thus obtained was compared with the printed wiring board of this example, and the product of the present invention had a finish with no color loss compared to the comparative product. Example 2 Pentaerythritol triacrylate 4 as a solution for photoresist layer
0 parts trimethylolpropane trimethacrylate
60 parts 2,4-dimethylthioxanthone
15 parts methyl violet
0.2 parts methyl ethyl ketone 8
Solution consisting of 00 parts carbon black 2 parts water
A dry film was prepared in the same manner as in Example 1, except that a dispersion obtained by ultrasonically dispersing a mixture consisting of 21 parts for 5 hours was used. After this dry film was adhered to a copper-clad laminate in the same manner as in Example], it was exposed from the dry film side to a YAG laser beam with an output s ws beam diameter of 20 μm at a scanning speed of 15 m/sec in the form of a negative image. A printed wiring board was produced in the same manner except that a 5% aqueous sodium phosphate solution was used to develop the photoresist layer. Example 3 A dry film was prepared in the same manner as in Example 1 except that a 50μ thick PVA film was used as the support.Hereafter, this dry film was used and instead of peeling the support,
A printed wiring board was prepared in the same manner as in Example 2, except that it was removed by dissolving in this aqueous solution during development with a 5% sodium phosphate aqueous solution.Effects As described above, the dry film of the present invention is a normal ultraviolet-sensitive photoresist layer. Since it is combined with a heat-sensitive layer that is sensitive to heat mode type laser light, medium (sW or less)
It has the advantage of not only being able to form an image using a laser with a power output of Procedural amendments dated July 27, 1980 Manabu Shiga, Commissioner of the Patent Office, 1. Indication of the case and its image formation method 3. Person making the amendment. Relationship with the case. Patent applicant: 1-chome Nakamagome, Ota-ku, Tokyo. 3 No. 6 (674) Ricoh Co., Ltd. Representative Hama 1) Hiro 4, Agent 6, Contents of the amendment 1) Page 30 of the specification, line 6, ``Created.'' and line 7 of the same.
Insert the following token between the line "Effect". Example 4 A dry film was prepared in the same manner as in Example 1 except that a dispersion having the following composition was used as the heat-sensitive liquid. Carbon black 2 parts 10% aqueous solution of dried egg white 20 parts Ionomer resin emulsion (Mitsui Petrochemical Industries, Ltd.) Chemical Pearl 5-too, solid content 27%) 2 parts P
A printed wiring board was prepared in the same manner as in Example 1 using a 10% aqueous solution of VA (degree of saponification 89%, average degree of polymerization 500), 1 part water, 5 parts or less, and this dry film. Example 5 A dry film was prepared in the same manner as in Example 1 except that a dispersion having the following composition was used as the heat-sensitive liquid.

Claims (1)

[Claims] 1. A photoresist layer is provided on one side of the plastic film support, and the top is further covered with a plastic film to serve as a protective film, and the other side is coated with (a) a photoresist layer that absorbs light and heats up. 1. A photothermosensitive dry film comprising: (b) a thermosensitive layer containing a photothermal converting material as a main component; and (b) a thermosensitive polymeric material whose solubility or redispersibility in water is reduced by heat. 2. A photoresist layer is provided on one side of the plastic film support, and the top is further covered with a plastic film to serve as a protective film, and the other side has (a) photothermal conversion property that absorbs light and converts it into heat. The protective film of the photo-thermo-sensitive dry film, which is provided with a heat-sensitive layer mainly composed of a substance and (b) a heat-sensitive polymer substance whose solubility or redispersibility in water is reduced by heat, is peeled off, and then the protective film is removed from the photosensitive layer. The surface of the resist layer is brought into close contact with the substrate on which a resist image is to be formed, and the dry film side is imagewise exposed to heat mode type laser light to detect the difference in solubility in water between the exposed and non-exposed areas of the heat-sensitive layer. Or, after creating a redispersibility difference, develop with water to selectively dissolve or redisperse the non-exposed areas of the heat-sensitive layer in this water, and then mask the remaining undissolved or undispersed exposed areas of the heat-sensitive layer. The entire surface of the dry film is exposed to light in the sensitive wavelength range of the photoresist layer to selectively dissolve the exposed or non-exposed areas of the photoresist layer between the exposed and unexposed areas of the photoresist layer. After creating a solubility difference in the developer, the support film is peeled off and then developed with the developer to selectively dissolve and remove the exposed or non-exposed areas of the photoresist layer in the developer. An image forming method characterized by leaving undissolved non-exposed or exposed areas of the photoresist layer on the substrate as a resist image. 3. A photoresist layer is provided on one side of the plastic film support, and the top is further covered with a plastic film to serve as a protective film, and the other side has (a) photothermal conversion property that absorbs light and converts it into heat. The protective film of the photo-thermo-sensitive dry film, which is provided with a heat-sensitive layer mainly composed of a substance and (b) a heat-sensitive polymer substance whose solubility or redispersibility in water is reduced by heat, is peeled off, and then the protective film is removed from the photosensitive layer. The surface of the resist layer is brought into close contact with the substrate on which a resist image is to be formed, and the dry film side is imagewise exposed to heat mode type laser light to detect the difference in solubility in water between the exposed and non-exposed areas of the heat-sensitive layer. Or, after creating a redispersibility difference, develop with water to selectively dissolve or redisperse the non-exposed areas of the heat-sensitive layer in this water, and then mask the remaining undissolved or undispersed exposed areas of the heat-sensitive layer. The entire surface of the dry film is exposed to light in the sensitive wavelength range of the photoresist layer to selectively dissolve the exposed or non-exposed areas of the photoresist layer between the exposed and unexposed areas of the photoresist layer. After creating a solubility difference in the developer that dissolves the support film together with
By developing with a developer, the exposed or unexposed areas of the photoresist layer are selectively dissolved and removed together with the support film in the developer, whereby the undissolved unexposed or exposed areas of the photoresist layer are removed from the substrate. An image forming method characterized by leaving a resist image on top.