JPH0313581B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to photopolymerizable imaging compositions. Conventionally, a composition consisting of a binder made of a polymeric material, a photopolymerizable monomer or oligomer, a photopolymerization initiator, etc. is applied to the surface of a base material, and then light is applied through a negative image, etc., and the parts that are exposed to the light are It is known that an image can be formed on a substrate by polymerizing or crosslinking to make it insolubilized in a solvent and eluting the areas that are not exposed to light.This principle is used for printing plates and printed wiring boards. Applied to manufacturing. It is also possible to add a photochromic agent such as a leuco dye to the above composition to make it possible to clearly distinguish between areas exposed to light and areas not exposed to light, thereby making it possible to perform multiple exposures, etc. Are known. For example, in the publication disclosed in Japanese Patent Publication No. 48-38403, a leuco dye is mixed into a composition in which imidazolyl dimer and P-aminophenyl ketone are added to an ethylene monomer, but it is generally used as a light source. When coloring a dye at the same time as photopolymerization or crosslinking in a composition using an ultraviolet light source such as a high-pressure mercury lamp, the presence of the dye reduces the photopolymerization or crosslinking rate, so the exposure time may be prolonged. This creates disadvantages that make it necessary to do so. This is presumed to be due to the fact that the optical energy absorbed by the photopolymerization initiator and the like is used for both polymerization or crosslinking and coloring of the dye. The present invention solves the above-mentioned conventional drawbacks.The present invention eliminates the color of the dyed area by irradiating it with light so that it can be distinguished from unexposed areas. The purpose of this invention is to provide an image-forming composition that has good workability and is suitable for multiple exposure. The gist of the present invention is (a) a binder made of a polymeric material, (b) a photopolymerizable monomer or oligomer, (c) a photopolymerization initiator, (d) an amino-substituted triarylmethane dye, and (e) a cyanogen selected from the group consisting of a group-substituted naphthalene compound, a cyan group-substituted naphthacene compound, a cyan group-substituted anthracene compound, a cyan group-substituted phenanthrene compound, and a benzonitrile compound, and whose light absorption wavelength range is different from that of the photopolymerization initiator described above. The present invention relates to a photopolymerizable image-forming composition containing a cyanated aromatic compound type photoactivator. The binder used in the present invention is made of a polymer material, and any binder conventionally used as a binder for image-forming compositions can be used. is important. Specific examples include acetylcellulose, acetylbutylcellulose, polymethylacrylate, polymethacrylic acid, methacrylic acid-methylmethacrylate copolymer, and the like. The photopolymerizable monomer or oligomer used in the present invention refers to a monomer or oligomer that is activated by light irradiation to initiate polymerization in the presence of a photopolymerization initiator, and has a boiling point of 100°C or higher at normal pressure. Those having at least one ethylene terminal group are preferably used. Specifically, polyalkylene glycol acrylates such as pentaerythritol acrylate (or methacrylate), polyethylene glycol diacrylate (or methacrylate), diethylene glycol diacrylate (or methacrylate), triethylene glycol diacrylate (or methacrylate), and polymethylene diacrylate. (or methacrylate), trimethylolproban triacrylate (or methacrylate), or oligomerized products thereof. These photopolymerizable monomers or oligomers form strong images by being entangled with the binder and becoming insolubilized by photopolymerization, or by polymerizing or crosslinking with the binder polymeric material having a photosensitive group. As the photopolymerization initiator used in the present invention, conventionally used initiators can be used, and among them, phenylketone-based photopolymerization initiators are preferred. Specific examples of photopolymerization initiators include benzophenone,
(λmax = 330 nm) (λmax indicates the wavelength of the highest peak of the optical absorption spectrum), P-aminophenyl ketone such as P,P'-bis(dimethylamino)benzophenone (hereinafter referred to as Michler ketone) (λmax - 370 nm), Benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin butyl ether, benzoin isopropyl ether (λmax=325nm), benzyl anthraquinone, 2-methyl-anthraquinone, 2-ethyl-
Examples include anthraquine (λmax=325nm), 2-tertbutyl-anthraquine (λmax=325nm), 2-aminoanthraquinone, and most of them are 320~
It absorbs light energy at a wavelength of 370 nm and is used as a polymerization initiator. Moreover, these photopolymerization initiators can also be used in combination of two or more types; for example, a mixture of benzophenone and Michler-Kent has different wavelengths of absorbed light, which improves the efficiency of polymerization initiation by irradiated light. This is preferable because the exposure time is further shortened. Next, in the present invention, a combination of an amino-substituted triarylmethane dye and a cyanated aromatic compound type photoactivator is used as a photodecolorizer. Due to the addition of the amino-substituted triarylmethane dye, the unexposed composition remains colored.
The photoactivator has a light absorption wavelength range different from that of the photopolymerization initiator. It is believed that the amino-substituted triarylmethane dye is reduced to a colorless or light-colored leuco dye by a cyanated aromatic compound type photoactivator. Specific examples of such amino-substituted triarylmethane dyes include: methyl violet, crystal violet, malachite green, bis(4-diethylamino-O-tolyl)phenylmethane, tris(4-diethylamino-O-tolyl)phenylmethane,
-diethylaminoO-tolyl)methane, bis(4
-diethylamino-O-tolyl)(p-benzylthiophenyl)methane, bis(4-diethylamino-O-tolyl)(3,4-dimethoxyphenyl)
Methane, bis(p-diethylamino-O-tolyl)(p-α-methoxyacetamidophenyl)
methane. Among the above dyes, bis(4-diethylamino-
O-tolylphenylmethane and below can be used in the form of hydrochloride, sulfate, oxalate, zinc chloride, double salt. In the present invention, the cyanated aromatic compound type photoactivator having a light absorption wavelength range different from that of the photopolymerization initiator is a cyanide group-substituted naphthalene compound, a cyanide group-substituted naphthacene compound, a cyanide group-substituted anthracene compound, or a cyanide group-substituted anthracene compound. It is a compound selected from the group consisting of group-substituted phenanthrene compounds and benzonitrile compounds, and is activated by irradiation with active light mainly in the wavelength range of 300 to 600 nm to reduce the above amino-substituted triarylmethane dye. It has no leuco body and is bleached to a colorless or light color so that it can be clearly distinguished from the colored non-exposed area.
Specific examples of the cyanated aromatic compound type photoactivator include 9-cyanoanthracene, 9,10-dicyanoanthracene, 1-cyanonaphthacene, and 1-cyanoanthracene.
Cyanonaphthalene, 2-cyanonaphthalene, 4-
Examples include acetylbenzonitrile, 9-cyanophenanthrene, and the like. These cyanide aromatic compound type photoactivators are selected to have a light absorption wavelength range different from that of the above-mentioned photopolymerization initiator, but the difference in light absorption wavelength range between the two is generally due to the absorption The difference in wavelength showing the highest peak of the spectrum is approximately 20 nm or more. However, if the distribution of absorption spectra of the photoactivator and photopolymerization initiator are both narrow, the difference between the highest peaks of the absorption spectra may be a few nanometers, and conversely, if the distributions are wide, for example, a difference of 50 nm or more is required. Therefore, both of them take into consideration the wavelength and distribution of the peak of the absorption spectrum, and the light of the wavelength that is mainly absorbed and used by the photopolymerization initiator activates the photoactivator and works as a reducing agent. The difference in the wavelength range is such that it is also used for decolorizing the amino-substituted triarylmethane dye and does not substantially inhibit the polymerization and curing of the composition. Therefore, in the present invention, the amino-substituted triarylmethane dye is reduced and decolorized using a cyanated aromatic compound photoactivator, but the reaction progresses reliably and rapidly compared to the conventional type in which color is developed by exposure. This has the advantage that only a small amount of photoactivator and dye is required. The aromatic cyanide compound must be mixed in solid form, and if used in large quantities, there is a risk that it may impede the adhesion with the copper-clad laminate, which will be described later. This will prevent such problems from occurring. When the composition of the present invention is used by laminating it on a copper-clad laminate or the like to which a thin copper foil is attached, an adhesion promoter may be mixed therein in order to improve the adhesion. Further, a thermal polymerization inhibitor, a plasticizer, a heat retardant, etc. can be added as necessary. In order to obtain the composition of the present invention, a binder made of the above-described polymeric material, a photopolymerizable monomer or oligomer, a photopolymerization initiator, an amino-substituted triarylmethane dye, and a light absorption wavelength range different from that of the photopolymerization initiator are used. It is sufficient to uniformly mix the cyanide aromatic compound type photoactivator and, if necessary, an adhesion promoter, etc., but usually a thin film is formed on the surface of the base material such as synthetic resin. Therefore, it is preferable to use a liquid composition that has clay that can be mixed with methyl ethyl ketone or other appropriate solvent and applied to a substrate, etc., and that can be dried by volatilization of the solvent. In addition, the quantitative relationship of the components of the above composition is as follows:
A photopolymerizable monomer or oligomer
10 to 300 parts by weight, 0.1 to 20 parts by weight of photopolymerization initiator,
0.01 to 10 parts by weight of amino-substituted triarylmethane dye, and cyanide aromatic complex type photoactivator.
It is preferable to use 0.001 to 1 part by weight. Furthermore, preferably the dye is 0.01 to 0.2 parts by weight and the photoactivator is
0.005-0.1 part by weight is used. The composition of the present invention can be used to create relief printing plates and photoresists, and usually a solution of the composition of the present invention dissolved in a solvent is applied onto a transparent sheet-like substrate and dried. If necessary, a protective film is formed thereon. Then, this is applied to the surface of a member on which an image such as a photoresist image is to be formed, such as a copper-clad laminate with thin copper foil pasted, by heat fusion, etc., after removing the protective film if necessary. Laminate the layers, irradiate the exposed areas with active light through a negative film, etc., and then peel off the transparent sheet-like base material if it remains, and remove the unexposed areas with a solvent, etc. After that, the unprotected portion of the surface (the portion from which the composition of the present invention has been removed by the solvent) is subjected to etching or metal plating treatment. In addition, the composition of the present invention decolorizes the exposed area by photoactivating and reducing the amino-substituted triarylmethane dye by the cyanide aromatic complex type photoactivator contained therein. It is easy to distinguish between exposed areas and non-exposed areas, which is very convenient when performing multiple exposures or checking exposure conditions. In addition, the amino-substituted triarylmethane dye and the cyanated aromatic compound type photoactivator can be used in extremely small amounts compared to conventional color-forming types, saving material and improving adhesion to copper-clad laminates. It has the advantage of not interfering with sexuality. Furthermore, the photoquenching agent, which is a combination of an amino-substituted triarylmethane dye and a cyanated aromatic compound type photoactivator in the composition of the present invention, does not cause the colored image to disappear in a short time after exposure, unlike in the conventional case. Without,
The stability of the decolored image is excellent and the workability is improved. Furthermore, when a leuco dye-based coloring agent is conventionally used, it is presumed that the energy of the irradiated light is divided into both polymerization or crosslinking of the composition and color development, but the polymerization and curing reaction of the composition compared to slower speeds and longer exposure times.
The composition of the present invention does not have such drawbacks, a short exposure time is sufficient, and the exposure workability is excellent. Example 1 Polymethyl methacrylate (=2.0×10 ⁵ )
60g Trimethylolpropane triacrylate 33g Benzophenone (maximum content = 330nm) 3.5g Michler's ketone (maximum content = 370nm) 1.5g Crystal Violet 0.08g 9,10-dicyanoanthracene (maximum content = 380,
400, 425nm) Dissolve 0.02g or more of the compound in methyl ethyl ketone,
A solution with a total amount of 300 g was applied to a polyethylene terephthalate film support so that the thickness after drying was 50 μm, and after drying the film, this was applied.
The above coating was laminated on a glass fiber reinforced epoxy resin plate coated with copper at a temperature of 160°C so as to be in contact with the copper surface. Next, place the above photosensitive laminate at a distance of 1m from a 400W high-pressure mercury lamp, and make a test negative (21√2 step exposure step guide = the negative is gradually made darker from a transparent state to 21 steps in increments of √2). Exposure of 90 millijoules (mj)/cm ² was carried out in vacuum through negative images for printed wiring circuits placed side by side so as not to overlap. The exposure time is
It was hot in 20 seconds. After exposure, the polyethylene terephthalate film support was peeled off, and the exposed layer was immersed in 1,1,1-trichloroethane for development (unexposed areas were removed).
Dry. For test negative images,
A 9-step image remained on the copper coated glass fiber reinforced epoxy resin board, and the resolution in the printed wiring image was 50 μm. Also, before the above development, the unexposed area is deep blue-purple (absorbance 1.0), and the exposed area is pale blue (absorbance 0.4).
The contrast was clear and sufficient for exposure inspection. Furthermore, after this exposure, it was left for a day and night, and the next day it was developed and etched, and a film was further coated to form a printed circuit, but a clear bleached image remained in the exposed area until the film was removed. It was convenient for inspecting the condition of Example 2 As a dye, 0.08 g of malachite green was used instead of crystal violet in Example 1. As a photoactivator, 1-cyanonaphthacene (maximum content = 396n) was used instead of 9,10 dicyanoanthracene in Example 1.
m) In the same manner as in Example 1 except that 0.02 g was used, a test negative image and a printed wiring negative image were exposed and developed to create a printed wiring circuit. The results are the degree of hardening of the exposed area, resolution,
It was observed that the degree of coloring contrast was the same as in Example 1 in all cases. Comparative Examples 1 to 4 Using the compositions shown in the table below, exposure, development, and formation of printed circuits were performed in the same manner as in Example 1. The results were as shown in the table below. 【table】

Claims (1)

[Scope of Claims] 1 (a) a binder made of a polymeric material, (b) a photopolymerizable monomer or oligomer, (c) a photopolymerization initiator, (d) an amino-substituted triarylmethane dye, and (e ) A photopolymerization initiator with a light absorption wavelength range selected from the group consisting of a cyan group-substituted naphthalene compound, a cyan group-substituted naphthacene compound, a cyan group-substituted anthracene compound, a cyan group-substituted phenanthrene compound, and a benzonitrile compound. 1. A photopolymerizable image-forming composition comprising a cyanated aromatic compound type photoactivator different from .