JPH02309358A - Positive type photosensitive resin composition - Google Patents

Abstract

PURPOSE:To increase the sensitivity of a compsn. by using a specified acrylic copolymer. CONSTITUTION:This compsn. contains an acrylic copolymer consisting of 30-70 wt.% t-butyl acrylate and other acrylic monomer (A) stable to acids and a compd. (B) generating an acid when irradiated with rays of active light. A combination of n-butyl acrylate with methyl methacrylate may be used as the component A, triphenylsulfonium hexafluoro arsenate as the component B and a desired dye may be added to this compsn. A mercury lamp may be used as a light source and an aq. soln. of sodium metasilicate as a developing soln.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a positive photosensitive resin composition.

(Prior Art) There are two types of photosensitive resin compositions: negative type (the area irradiated with light hardens) and positive type (the area irradiated with light dissolves in a developer). Positive type has higher resolution than negative type, and is widely used in lithographic printing and as a resist material.

This positive type photosensitive resin composition generally utilizes a reaction in which a quinone diazide group is decomposed by light and converted into an indenecarboxylic acid via a ketene compound. This generated indenecarboxylic acid group makes it possible to elute in alkaline water. However, this quinonediazide type has low sensitivity, long exposure time, and poor working efficiency.

JP-A-59-45439 discloses a resist composition containing a compound that generates an acid when irradiated with light and a polymer that releases free carboxylic acid groups when exposed to the acid.

(Problems to be Solved by the Invention) The present inventors have studied the compositions described in the above-mentioned Japanese Patent Application Laid-Open No. 59-45439, but none of the compositions actually disclosed in this publication have been used for printing purposes. I realized what I wasn't doing with enough sensitivity. The present invention aims to improve this composition and obtain a new composition that has higher sensitivity and can be used for printing.

(Means for Solving the Problems) That is, the present invention consists of (a) t-butyl acrylate and an acrylic monomer stable against other acids, and t-butyl acrylate is 30 to 70% by weight of the total monomer weight. Provided is a positive photosensitive resin composition containing an acrylic copolymer having the following properties and (b) a compound that generates an acid upon irradiation with actinic rays.

The composition of the present invention has a light wavelength of 254 to 365 nm, compared to the composition described in JP-A-59-45439.
It has 0 times higher sensitivity and is suitable for printing. Japanese Unexamined Patent Publication 1983
The polymer of No. 45439 is, for example, poly-(tert-butyl methacrylate), that is, a methyl group A is always present on the α-carbon atom on the polymer backbone to which a tert-butyl group is pendant, as shown in have.

The compound of the present invention does not have a methyl group, but has a hydrogen atom. It is completely unexpected that this difference would result in a sensitivity that is approximately 40 times higher.

The acrylic copolymer of the present invention consists of 30 to 70 weight percent t-butyl acrylate and the remaining amount of acrylic monomers that are stable against other acids. (-butyl acrylate is 30
If the amount is outside the range of 70% by weight, the sensitivity will be significantly reduced. Acrylic monomers copolymerized with t-butyl acrylate monomer and stable to filtrate include acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, and acrylic. Examples include hexyl acid, 2-ethylhexyl acrylate, isooctyl acrylate, lauryl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, and 2-hydroquinepropyl methacrylate. The copolymerization of these monomers is carried out in a manner known per se. For example, rancal polymerization may be performed in a suitable solvent.

Examples of compounds that generate acid upon irradiation with actinic rays include diazonium, sulfonium, phosphonium, and iodonium S bFe''-, AsF 1l-1P
Examples include salts such as F, -1BF', and -. Specific examples of these compounds include 4-(di-n-propylamino)-benzezonoazonium tetrafluoroborate, 4-p-
Tolyl-mercapto-2,5-jethoxybenzenediazonium hexafluorophosphate, triallylsulfonium tetrafluoroborate and hexafluoroarsenate, trianisylsulfonium tetrafluoroarsenate, diphenyl(4-thiophenylphenyl)sulfonium hexafluoro Arsenate, diphenyliodonium tetrafluoroborate and hexafluoroarsenate, bis(p-chlorophenyl)
These include iodonium tetrafluoroborate and hexafluoroarsenate. The amount of acid-generating compounds is from 0.1 to 50% by weight, preferably from 0.2 to 20% by weight of the total composition. When the amount is less than 0.2% by weight, the amount of protons (H+) generated is small, so that sufficient hydrolysis of the ester group does not occur. If the amount exceeds 20% by weight, the compatibility with the acrylic copolymer becomes poor and precipitation occurs during long-term storage.

The composition of the present invention is prepared by mixing the acrylic copolymer and the acid-generating compound, either as such or in a solvent if necessary, in a cool, dark place. Solvents that can be used include ketones such as acetone, methyl ethyl ketone, cyclohexanone, etc.; esters,
For example, ethyl acetate, butyl acetate, ethylene glycol acetate, etc.; ethers, such as tetrahydrofuran,
Examples include dioxane.

If necessary, a dye pigment may be added to the photosensitive resin composition of the present invention for the purpose of sensitization. Examples of such dyes and pigments include perylene, pyrene, phenodeazine, anthracene, coronene, 1°2-benzanthracene, and the like.

The positive photosensitive resin composition of the present invention is coated on a support and dried, then exposed and developed using a positive film. Coating is performed by spin coating, wire bar coating, dip coating, or roll coating. Light sources used to solubilize the photosensitive layer by light irradiation include ultra-high pressure mercury lamps, metal halide lamps, xenon lamps, low-pressure mercury lamps, and the like. For development, use a hydrogen-alkaline developer such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate,
Sodium metasilicate, potassium metasilicate, etc. are used. The agricultural product of this product is used in the range of o, t-to weight percent. If it is less than 0.1% by weight, it will take a long time to elute and 10% by weight.
Above this, the remaining film will be adversely affected and handling will become difficult.

(Effects of the Invention) The positive photosensitive resin composition of the present invention has high sensitivity and is suitably used for various uses, particularly for printing.

(Example) The present invention will be explained in more detail with reference to Examples. The invention is not limited to these examples.

Synthesis Example 1 Tert-butyl acrylate 15. After adding Og, 1-butyl acrylate and 260 g of methyl methacrylate, the mixture was heated and stirred at 60° C. for 10 hours in a nitrogen stream. After cooling, the reaction product was diluted with THP and petroleum ether was added to precipitate the resin. The white resin was washed with petroleum ether methanol.

The polymer was 20.6 g (854% yield) and had a number average molecular weight (GPC) of 51,000.

Synthesis Example 2 Tertiary butyl acrylate 25. The process was carried out in the same manner as in Synthesis Example 1, except that Og, 5.0 g of 1-butyl acrylate I, and 100 g of methyl methacrylate were used.

The obtained polymer had 21.6 g (86.4% yield) and a number average molecular weight (CI) of 46,000.

Synthesis Example 3 Tertiary butyl acrylate 35. Og and acrylic acid No.
The same procedure as in Synthesis Example 1 was carried out except that 15.0 g of butyl was used. The obtained polymer was 21.5g (yield 86.0%)
, number average molecular ff1 (GPC) was 54,000.

Treatment was carried out in the same manner as in Synthesis Example I except that tert-butyl acrylate lO,Og, 1-butyl acrylate l 5.0 g and methyl methacrylate 300 g were used.

The obtained polymer was 20.8 g (yield 83.4%) and had a number average molecular weight (GPC) of 42.000.

Synthesis Example 5 Tertiary butyl acrylate 50. The process was carried out in the same manner as in Synthesis Example 1 except that Og was used. The obtained polymer was 20.9 g (yield 83.6%), number average molecular weight (G P C) 39.0
It was 00.

Synthesis Example 6 15.0 g of tert-butyl methacrylate, 1-1 butyl acrylate 5. Og and methyl methacrylate 20, Og
was treated in the same manner as in Synthesis Example 1. The obtained polymer was 21.
3g (yield 85%), number average molecular weight (GPC) 36.0
It was 00.

Example 1 The copolymer of Synthesis Example 1 was TI (solid matter in P was 20f)
Fiff is dissolved to 1% and triphenylsulfonium hexafluoroarsenate is added in an amount of 5% by weight based on the polymer. This solution is coated onto a metal support with a wire bar to a thickness of 5.0 microns. Thereafter, it was dried at 80° C. for 10 minutes. Using a low-pressure mercury lamp as a light source, light with a wavelength of 254 nm was exposed through a quartz mask at 10xJ/cta'. After further heating at 90° C. for 1 minute, the film was developed in a 1% sodium metasilicate aqueous solution at 20° C. for 60 seconds to obtain a box-shaped image.

The same operations as in Example I were performed on the copolymer of Senkigeki Main Synthesis Example 2. Exposure to light of 8 rJ/cm'' and heating at 90° C. for 1 minute yielded a box-shaped elephant.

Example 3 The copolymer of Synthesis Example 2 was mixed with 'l' I (solid matter in F or 20
Dissolve diphenyliodonium hexafluoroarsenate in an amount of 5% by weight and add 1X10-'M of acridine orange to the polymer. This solution is coated onto a metal support to a thickness of 5.0 microns. Thereafter, it was dried at 80° C. for 10 minutes, and exposed to light with a wavelength of 365 nI11 at 15 zJ/am' through a mask using a high-pressure mercury lamp as a light source. After further heating at 90°C for 1 minute, a positive image was obtained by developing in a 1% sodium metasilicate aqueous solution at 20°C for 60 seconds.

Example 4 The copolymer of Synthesis Example 3 was operated in the same manner as in Example 1, and a positive image was obtained by exposing it to 5 x J/cm' and heating at 90°C for 1 minute.

Comparative Example 1 The copolymer of Synthesis Example 4 was subjected to the same operation as in Example 1, or an image could not be obtained even though it was heated with 100 iJ/c♂ light and 90° C. for 1 minute.

Comparative Example 2 The copolymer of Synthesis Example 5 was subjected to the same operation as in Example 1, except that the copolymer of Synthesis Example 5 was treated with 1
No image could be obtained even after heating for several minutes.

Comparative Example 3 The copolymer of Synthesis Example 6 was subjected to the same operation as in Example 1, but a positive image was obtained only by heating at 150° C. for 2 minutes with exposure of 360 ffJ/cm”.

Claims (1)

[Claims] 1. (a) An acrylic copolymer consisting of t-butyl acrylate and another acid-stable acrylic monomer, in which t-butyl acrylate accounts for 30 to 70% by weight of the total monomer weight. , and (b) a positive photosensitive resin composition containing a compound that generates an acid upon irradiation with actinic rays.