KR20040008817A - Coating solution composition for coating the phosphor screen of the cathode ray tube - Google Patents

Abstract

PURPOSE: A coating solution composition for coating the surface of a fluorescent substance of a color Braun tube is provided, to prevent the residue due to a coating solution composition from being left when an aluminum evaporation-deposition layer is formed on the coating solution and to improve the brightness of a fluorescent surface. CONSTITUTION: The coating solution composition comprises 2-10 wt% of a copolymer as a binder resin; a diluent; and an additive, wherein the copolymer is obtained by copolymerizing 10-50 wt% of vinyl toluene modified acrylate, 10-50 wt% of methyl methacrylate, 10-50 wt% of isobutyl methacrylate, and 5-50 wt% of at least one copolymeric monomer selected from acrylic acid, methacrylic acid, butyl acrylic acid, hydroxy methacrylate, maleic acrylate and t-butyl aminoacyl acrylate preferably in the presence of a catalyst by solution polymerization, and has a molecular weight of 5,000-50,000. Preferably the catalyst is at least one selected from the group consisting of benzyl peroxide, hydrogen peroxide, di-t-butyl peroxide, lauroyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide and azoisobutyronitrile.

Description

Coating solution composition for coating the phosphor screen of the cathode ray tube}

The present invention relates to a coating liquid composition used for coating a phosphor surface of a color brown tube (Cathode Ray Tube), more specifically, containing a copolymer copolymerized using monomers such as vinyl modified acrylate (Vinyl modified acrylate) It relates to a water-soluble coating liquid composition.

In general, the fluorescent film of a color CRT tube converts electron beam energy emitted from an electron gun into light energy, and realizes an image by excitation emission of a phosphor, and is made through a black matrix forming process and a red, green, and blue fluorescent pattern forming process. . The formed fluorescent film improves the brightness of the fluorescent film and prevents the potential drop of the fluorescent film, which forms a thin aluminum film through vacuum deposition of aluminum in order to prevent burning of the fluorescent film which is weak to impact.

However, since the fluorescent film formed directly as described above is not flat in the fluorescent film itself, the effect of aluminum as a mirror upon direct aluminum deposition is reduced. Therefore, in general, a method of improving the transparency and brightness of the fluorescent surface by smoothing an aluminum film by forming an intermediate film by coating and drying a special coating liquid composition on a fluorescent film and then performing aluminum deposition is used.

As described above, a coating liquid composition for forming a film film for improving the properties of an aluminum deposited film is mainly known as a coating liquid composition using an acrylic emulsion as a binder. For example, Korean Patent Laid-Open Publication No. 1994-4684 discloses a coating liquid composition for an aluminum deposition film in which an uniside, hydrogen peroxide solution, colloidal silica, glycerin, ammonia water, pure water and a small amount of anionic surfactant are added with an acrylic emulsion as a main component. Also, Korean Patent Publication No. 2000-34870 discloses a composition comprising an emulsion containing various additives and hydrogen peroxide, using a copolymer obtained by copolymerizing 1 to 13 monomers together with butyl methacrylate as a main component. .

However, as described above, the conventional coating liquid composition using an acrylic emulsion as a binder forms a film film on the surface of the phosphor of the color brown tube due to the polymer properties in the emulsion state, and forms an aluminum deposition film thereon, and finally calcinates at around 400 ° C. In this case, there is a problem that residues tend to remain and the luminance or transparency improvement of the fluorescent screen does not reach a satisfactory level.

The present invention has been made to solve the above problems, in particular, a new film film is formed on the surface of the phosphor of the color CRT tube to form a uniform aluminum deposition film on the film film and the coating liquid composition when firing at 400 ℃ after forming the aluminum deposition film It is an object of the present invention to provide a new coating liquid composition having a characteristic of having no residue (residue) and improving the brightness and transparency of the fluorescent surface after the final aluminum deposition.

The present invention is a coating liquid composition used for the coating on the phosphor surface of the color brown tube, vinyl toluene modified acrylate (Vinyltoluene modified acrylate) 10 to 50% by weight, methyl methacrylate 10 to 50% by weight, isobutyl methacrylate 10-50% by weight and one or two or more copolymerized monomers selected from acrylic acid, methacrylic acid, butyl acrylate, hydroxy acrylate, hydroxy methacrylate, maleic acrylate and t-butylaminoacyl acrylate The present invention relates to a coating liquid composition comprising 2 to 10% by weight of a copolymer having a molecular weight of 5,000 to 50,000 obtained by copolymerizing by weight, and composed of other additives and pure water.

Hereinafter, the present invention will be described in detail.

In the present invention, vinyltoluene-modified acrylate, methyl methacrylate and isobutyl methacrylate are mainly used as binder resins of the coating liquid composition, and acrylic acid, methacrylic acid, butyl acrylate, hydroxy acrylate, and hydroxy are copolymerized monomers. A copolymer obtained by copolymerizing together one or two or more monomers selected from oxy methacrylate, maleic acrylate and t-butylaminoacyl acrylate is used, but another acid or acryl is used in a range that does not impair the physical properties of the copolymer. The use of the monomer of the rate system is also possible. The amount of the monomer used is preferably in the range of 10 to 50% by weight of vinyltoluene-modified acrylate, methyl methacrylate and isobutyl methacrylate, and the use of copolymerized monomers such as acrylic acid in the range of approximately 5 to 50% by weight. desirable.

On the other hand, the above-mentioned patents are carried out emulsion polymerization in the form of copolymerization, in the present invention, the copolymerization is carried out by solution polymerization, the polymerization catalyst used is benzyl peroxide, hydrogen peroxide, DTBP (Di-t-butyl peroxide) ), Lauroyl peroxide, TBHP (t-butyl hydroperoxide), cumenehydroperoxide (Cumenhydroperoxide), t-butyl peroxide, AIBN (Azobisisobutyronitril), etc. can be used alone or in combination of two or more. The amount of use is preferably in the range of about 0.5 to 10% by weight.

In addition, as a solvent participating in the reaction during solution polymerization, water-soluble solvents such as acetone, DMF, IPA (Isopropyl alcohol), cellosolve, NMP, and the like are used, and the solid content is added so that the solid content is 30 to 50% by weight.

In order to improve the coatability and sintering of the composition coated on the phosphor surface of the color CRT in the present invention, the molecular weight of the binder resin obtained above is preferably in the range of approximately 5,000 to 50,000, and thus the molecular weight regulator during copolymerization by solution polymerization. To adjust the molecular weight. At this time, the molecular weight modifiers that can be used include d-mercaptan, t-dodecylmercaptan, p-benzquinone, p-hydroquinone nitrobenzene, dinitrobenzene, allyl Acetate or the like may be used alone, or two or more thereof may be used, and the amount thereof is preferably in the range of about 0.05 to 5% by weight.

When the polymerization is completed by performing the copolymerization reaction under the conditions as described above, the pH of the coating liquid composition is adjusted to a range of about 8 to 10. At this time, pH adjusting agents used include ammonia water, triethylamine, diethylamine, and the like. . Thus, the composition adjusted to pH of 8-10 is diluted with pure water like ion-exchange water so that solid content may be about 2 to 10 weight%.

The coating liquid composition thus obtained is coated on the surface of the phosphor of the color brown tube, but is not particularly limited as a coating method, but a spraying method or a method of injecting a defense is generally used, and the Tg of the coating film after coating drying is approximately 50 to Forming a strong coating film in the range of 90 ℃ to prevent the settlement of the aluminum layer deposited on the coating layer to form a uniform aluminum film. In addition, since the residue of the coating agent is hardly detected when firing at 400 ° C. after the aluminum deposition film is formed, it is possible to obtain advantages such that the screen brightness of the finished color-brown tube is not disturbed.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the protection scope of the present invention is not limited thereto.

Example 1

(1) Coating liquid composition manufacturing process

20 parts by weight of vinyl toluene modified acrylate, 30 parts by weight of methyl methacrylate, 30 parts by weight of isobutyl methacrylate, 10 parts by weight of acrylic acid, 10 parts by weight of butyl acrylate, 0.5 parts by weight of benzyl peroxide, and d-mercaptan 0.1 The weight parts were mixed and added to the separating nipples.

Put 100 parts by weight of IPA in a reaction flask equipped with a stirrer and raise the temperature while stirring to maintain the mixture at 80-90 ° C. while titrating the mixed solution contained in the separatory noodle for 2 hours, and then the reaction was terminated when the solid content was 50 wt%. Cooled. When the temperature of the reaction solution was 50 ° C. or less, ammonia water was added to adjust the pH to 9, and ion-exchanged water was added to make the solid content 6% by weight.

(2) post-treatment process

The coating liquid composition obtained in (1) was coated and dried on the surface of the color CRT phosphor by a spray method, and then an aluminum film was deposited, and then fired at 400 ° C. through a sealing process.

Example 2

The monomer used in the copolymerization in Example 1 is 30 parts by weight of vinyl toluene modified acrylate, 30 parts by weight of methyl methacrylate, 20 parts by weight of isobutyl methacrylate, 10 parts by weight of methacrylic acid, and 5 parts by weight of hydroxy methacrylate. Except for using 5 parts by weight of the portion and maleic acrylate was carried out in the same manner as in Example 1 to prepare a coating solution composition and a post-treatment step.

Comparative Example 1

(1) Coating liquid composition manufacturing process

500 parts by weight of butyl methacrylate, 4 parts by weight of hydroxyethyl methacrylate, 5 parts by weight of methacrylic acid were added 600 g of pure water and 4 g of sodium dodecyl sulfosuccinate as a surfactant, and 15 g of potassium persulfonate as a polymerization initiator. Then, the mixture was heated up and emulsified at 75 ° C. to obtain a butyl methacrylate emulsion.

(2) post-treatment process

The coating liquid composition obtained in (1) was coated on a surface of a color brown tube phosphor by a rotary coating method, and dried, and then an aluminum film was deposited, and then fired at 450 ° C. through a sealing process.

As a result of measuring the luminance of the phosphors obtained in the above Examples and Comparative Examples, those obtained in the Examples according to the present invention showed approximately 110% of the luminance than those obtained in the Comparative Examples, and visually confirmed the residue of the coating liquid composition after firing. No residue was observed in the one obtained in the examples, and a small amount of the residue was observed in the one obtained in the comparative example.

As confirmed in the Examples and Comparative Examples, when the coating liquid composition according to the present invention is used for phosphor coating of a color brown tube, residues due to the coating liquid composition do not remain when the aluminum deposition film is formed on the coating liquid, as compared with the conventional coating liquid composition. In addition, the effect of improving the luminance of the fluorescent surface can be obtained.

Claims (3)

In a coating liquid composition for coating a surface of a phosphor of a conventional color brown tube composed of a copolymer, a diluent, and an additive, which is a binder resin, the copolymer, which is a binder resin, is 10 to 50% by weight of vinyl toluene-modified acrylate, and 10 to 50 methacrylate. Wt%, isobutyl methacrylate 10-50 parts by weight, and copolymerization of one or two or more selected from acrylic acid, methacrylic acid, butyl acrylate, hydroxy methacrylate, maleic acrylate and t-butylaminoacyl acrylate A copolymer having a molecular weight of 5,000 to 50,000 obtained by copolymerization of 5 to 50% by weight of monomers by solution polymerization, wherein the copolymer contains 2 to 10% by weight in the composition. . The method of claim 1, wherein the polymerization catalyst used in solution polymerization is benzyl peroxide, hydrogen peroxide, di-t- butyl peroxide, lauroyl peroxide, t- butyl hydroperoxide, cumene hydro peroxide, azoisobutyronitrile 1 or 2 or more mixed catalysts selected from among, the coating liquid composition for coating the surface of the phosphor of the color brown tube, characterized in that it is added in the range of 0.5 to 10% by weight. The method of claim 1, wherein the copolymer has a molecular weight of at least one molecular weight modifier selected from di-mercaptan, t-dodecylmercaptan, p-benzquinone, p-hydroquinone, nitrobenzene, dantrobenzene and allyl acetate. A coating liquid composition for coating the surface of the phosphor of the color brown tube, characterized in that it is adjusted to use 0.05 to 5% by weight.