Radiation imagery chemistry: process – composition – or product th – Diazo reproduction – process – composition – or product – Composition or product which contains radiation sensitive...
Reexamination Certificate
2001-01-02
2002-01-29
Chu, John S. (Department: 1752)
Radiation imagery chemistry: process, composition, or product th
Diazo reproduction, process, composition, or product
Composition or product which contains radiation sensitive...
C430S007000, C430S167000, C430S196000, C430S325000
Reexamination Certificate
active
06342330
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to photosensitive compositions, more particularly to water-soluble photosensitive compositions suitably used for the formation of color filters, phosphor patterns, and black matrices of color cathode-ray tubes.
2. Description of Conventional Art
Conventionally, negative-type photoresists used for the formation of black matrices and phosphor patterns of color cathode-ray tubes, etc., have made use of resists composed of a water-soluble polymer such as polyvinyl alcohol and a bichromate salt (called PVA-ADC-based resists). Photoresists of this type have a fundamental disadvantage in that they require a special treatment facility for preventing environmental pollution, which is otherwise caused due to the presence of bichromate salts.
As photoresists that are free from the above problem, there have been known photosensitive compositions containing a water-soluble diazide compound, e.g., sodium 4,4′-diazidostilbene-2,2′-disulfonate (hereinafter abbreviated DAS), which serves as a photocrosslinking agent, and a water-soluble polymer that is photocrosslinkable in the presence of the water-soluble diazide compound. For example, there are proposed photosensitive compositions containing, as polymer matrices, vinyl alcohol-maleic acid copolymers or salts thereof (Japanese Patent Application Laid-Open (kokai) No. 48-97602), vinyl alcohol-acrylamide copolymers (Japanese Patent Application Laid-Open (kokai) No. 48-97603), or water-soluble polyvinylbutyrals (Japanese Patent Application Laid-Open (kokai) No. 48-98905). In practice, however, these compositions cannot be used because of their low sensitivity. At present, known compositions having sufficient sensitivity in practice include those containing polyvinylpyrrolidone (hereinafter abbreviated PVP) and a water-soluble diazide compound serving as an additive (hereafter, compositions of this type will be referred to as PVP-DAS-based resists; see, for example, Japanese Patent Application Laid-Open (kokai) No. 48-90185), as well as those containing an acrylamide-diacetoneacrylamide copolymer (hereinafter abbreviated PAD) and water-soluble diazide serving as an additive (hereafter, compositions of this type will be referred to as PAD-DAS-based resists; see, for example, Japanese Patent Application Laid-Open (kokai) No. 50-33764).
When used for the formation of black matrices of color cathode-ray tubes, PVA-ADC-based resists have a drawback of poor resolution, in addition to the aforementioned problem of environmental pollution, due to low oxygen permeability and lack of reciprocity-law failure characteristics. In contrast, when PVP-DAS-based resists are used, due to their excessively high oxygen permeability, proper sensitivity cannot be obtained unless the thickness of coating film is increased, which in turn reduces resolution. PAD-DAS-based resists, on the other hand, are endowed with excellent sensitivity and resolution, but after they have undergone formation of resist patterns and coating with graphite they provide poor etching characteristics, and, depending on the type of graphite, etching cannot be effected.
With regard to use for the formation of phosphor patterns, PVA-ADC-based resists are unsatisfactory in terms of both environmental pollution and sensitivity, and in addition, chromium oxide which remains after firing degrades the luminance of the phosphor. In this respect, PVP-DAS-based resists and PAD-DAS-based resists have drawbacks in terms of sensitivity, and therefore cannot be used.
Meanwhile, there are known non-chromium resists which are used for the formation of phosphor patterns and which contain as a photosensitive unit a photosensitive resin obtained through a condensation reaction between unmodified polyvinyl alcohol and a quaternary ammonium salt (e.g., a styrylpyridinium salt or a styrylquinolinium salt) (Japanese Patent Application Laid-Open (kokai) Nos. 55-23163, 55-62905, and 56-11906). However, these resists are also unsatisfactory in terms of resolution.
As described above, there exist no conventional photoresists that simultaneously satisfy requirements with respect to environmental pollution, sensitivity, and resolution. Therefore, there is still need for novel resist materials that exhibit excellent characteristics.
SUMMARY OF THE INVENTION
In view of the foregoing, an object of the present invention is to provide photosensitive compositions which do not cause environmental pollution and which exhibit high resolution and satisfactory sensitivity.
In order to overcome the above-described drawbacks, a first mode of the present invention is directed to a photosensitive composition which contains a water-soluble azide compound serving as a-photocrosslinking agent and poly(N-vinylacetamide) that is photocrosslinkable in the presence of the water-soluble azide compound.
In a second mode of the present invention, the photosensitive composition according to the first mode further contains another water-soluble polymer that is photocrosslinkable in the presence of the above-described water-soluble azide compound.
In a third mode of the present invention, the photosensitive composition according to the second mode contains the water-soluble polymer which comprises at least one species selected from the group consisting of polyvinylpyrrolidone, acrylamide-diacetoneacrylamide copolymers, poly (N,N-dimethylacrylamide), and N,N-dimethylacrylamide-acrylamide copolymers.
In a fourth mode of the present invention, the photosensitive composition according to any of the first through third modes further contains additives and at least one species of water-soluble polymers.
In a fifth mode of the present invention, there is provided a pattern formation method which comprises forming a photosensitive composition layer on a substrate by applying a photosensitive composition according to any of the first through fourth modes; to a substrate performing a pattern exposure on the photosensitive composition layer; and subsequently developing the resulting exposed layer with water or an aqueous developer.
In a sixth mode of the present invention, the above-described substrate employed in the method according to the fifth mode serves as an inner surface of a face plate of a color cathode-ray tube.
A seventh mode of the present invention is directed to a photosensitive composition for the formation of a black matrix, wherein the composition is used for the formation of a black matrix of color cathode-ray tubes and which contains a water-soluble azide compound serving as a photocrosslinking agent and a water-soluble polymer which is photocrosslinkable in the presence of the water-soluble azide compound, wherein the above-described photocrosslinkable water-soluble polymer predominantly contains poly(N-vinylacetamide) and further contains another water-soluble polymer having reciprocity-law failure characteristics more prominent than those of the corresponding poly(N-vinylacetamide).
In an eighth mode of the present invention, the water-soluble polymer contained in the photosensitive composition according to the seventh mode is at least one species selected from the group consisting of polyvinylpyrrolidone, acrylamide-diacetoneacrylamide copolymers, poly(N,N-dimethylacrylamide), and N,N-dimethylacrylamide-acrylamide copolymers.
A ninth mode of the present invention is directed to a photosensitive composition for the formation of a phosphor pattern, wherein the composition contains a water-soluble azide compound serving as a photocrosslinking agent; a water-soluble polymer which is photocrosslinkable in the presence of the water-soluble azide compound; and a phosphor; and which is prepared by dissolving or dispersing these in an aqueous medium, wherein the above-described. photocrosslinkable water-soluble polymer contains poly(N-vinylacetamide).
In a tenth mode of the present invention, the photosensitive composition for the formation of a phosphor pattern according to the ninth mode further contains at least one species selected from among sap
Tagoshi Hirotaka
Tochizawa Noriaki
Watanabe Masaharu
Yamaguchi Tetsuhiko
Chu John S.
Sughrue & Mion, PLLC
Toyo Gosei Kogyo Co. Ltd.
LandOfFree
Photosensitive compositions and pattern formation method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Photosensitive compositions and pattern formation method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photosensitive compositions and pattern formation method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2856687