KR950013864B1 - Screen manufacture method of crt - Google Patents

Abstract

The method for manufacturing fluorescent plate of a color cathode ray tube comprises the steps of: doping and drying the photosensitive resin composite inside of the face of the color cathode ray tube; detecting ultraviolet ray via a fluorescent plate mask and exposing a predetermined portion thereof; scatteringly attaching fluorescent powder inside of the face and collecting surplus fluorescent powder; and cleaning the inside of the face with purity and processing the formed fluorescent plate pattern with boric acid solution.

Description

Photosensitive resin composition for color cathode ray tube and fluorescent surface manufacturing method using the same

1 is a process diagram showing the method of the present invention.

2 is a photograph showing the stripe shape of the fluorescent film obtained by the present invention.

3 is a photograph showing a stripe shape of a fluorescent film obtained by a conventional slurry coating method.

The present invention relates to a photosensitive resin composition for forming a fluorescent surface of a color cathode ray tube and a fluorescent surface manufacturing method using the same.

On the inner surface of the face of the color cathode ray tube, three-color phosphor patterns of red, blue, and green are arranged to form a fluorescent surface.

As a method of coating these phosphors to form a predetermined pattern on the inner surface of the face, a slurry coating method using a photosensitive resin composition mixed with phosphors, and a mercury-excited ultraviolet ray are decomposed to decompose the diazonium salt, where zinc chloride is in the air. There is a drying method using a photosensitizer made of a diazonium salt that absorbs moisture and exhibits stickiness.

In the former slurry coating method, a phosphor slurry is applied to an inner surface of a face, and only a predetermined portion is exposed through a shadow mask, and then a non-exposed portion is washed and developed. The exposure time is long and exposed due to the low sensitivity. Ultraviolet rays cause light scattering on the surface of the phosphor, and thus there is a problem in that fine and clear phosphor patterns cannot be obtained.

In the latter drying method, the photosensitive agent is applied to the inner surface of the face and dried, followed by exposure, scattering and adhering the phosphors, washing the phosphor remaining in the non-exposed part with air and administering a loading agent to lose the viscosity provided by the exposed photosensitive agent. As a method of forming by forming, it is possible to obtain a phosphor pattern of a higher quality than the slurry coating method described above, but since it must be cleaned with air, it is difficult to cleanly remove the phosphor remaining in the non-exposed part, which causes color gaze upon application of the next phosphor film. have.

The sharpness of the screen in the color cathode ray tube depends on how fine, straight and right the fluorescent film pattern of three colors of red, blue and green can be formed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a photosensitive resin composition having no change in adhesiveness even after exposure and drying and having a wide drying temperature range.

Another object of the present invention is to provide a fluorescent surface forming method which can obtain a square and clear high definition fluorescent film pattern by using the photosensitive resin composition.

Accordingly, the photosensitive resin composition of the present invention is 10-5% pure water, 5-30% polyvinyl alcohol, 0.5-5% dichromate salt, 0.5-5% diethylene glycol, 0.5-5% ethylene glycol, 0.5-5% urea , 0.5-5% acetamide, 0.5-10% butanediol, 0.5-5% paraaldehyde, 0.5-5% dioxane, 0.5-5% surfactant.

In the method for forming a fluorescent surface using the composition, the above-described composition is applied to the inner surface of the face of the color cathode ray tube, exposed and dried, and then the phosphor powder is dispersed and adhered to the exposed portion, and the phosphor of the non-exposed portion is removed with water. Treatment with boric acid solution is carried out in the order of shrinking and fixing the phosphor pattern.

Hereinafter, the present invention will be described with reference to the accompanying drawings.

First, the photosensitive resin composition of the present invention is composed of the following materials.

,

로 응고된 이온화기로서 공유결합을 가진다. 이 공유결합점들은 다음 폴리비닐 알콜체인의 이온화된 기에 의해 포화되어 3차원적 광가교를 이루게 되어 물에 대한 용해도를 상당히 감소시켜 준다.Polyvinyl alcohol: 5-30% is added. It has the property of photocrosslinking due to the reduced trivalent chromium with light having a wavelength of 364nm. That is, the carboxyl group, which is the final decomposed product during the oxidation and reduction reaction, forms a compound of trivalent chromium and an octahedron. This carboxyl group is structurally

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It has a covalent bond as the ionizer solidified with. These covalent bonds are then saturated by the ionized groups of the polyvinyl alcohol chain, resulting in three-dimensional photocrosslinking, which significantly reduces the solubility in water.

Dichromate salt: 0.5-5% is added. Reacts with polyvinyl alcohol to keep photosensitivity stable under heat and other external influences. In the present invention, the dichromate salt showed the best result using potassium dichromate salt.

Diethylene glycol: 0.5-5% is added. Used as a plastic material.

Ethylene glycol: 0.5-5% is added. Determine photosensitivity and dryness. In this experiment, a first-class reagent from a Japanese quasi-standard or higher company was used.

Urea and acetamide: reduced by 0.5-5% These materials, which contain amines, maintain the dry state in the formation of the fluorescent film, and absorb moisture in the air to improve the crystallinity of the fluorescent film. In the present invention, Japanese Hayashi company first grade was used.

Butane diol: 0.5-10% is added. It is included in the overall composition to act as a plasticizer.

Paraaldehyde and dioxane: It acts as a plasticizer to control the evaporation rate of the composition and keeps the dry state of the photosensitive resin film constant.

Surfactant: It is made by dissolving 6 g of Tamok 731SD from Rohm & Hass in USA in 100 ml of hot water and adding 4-5 drops of Triton CF-10.

The composition process of the above-described material is as follows.

First, diethylene glycol and ethylene glycol are added while stirring pure water and polyvinyl alcohol diluent at room temperature. Stir for about 10 minutes, mix well, and then add urea, acetamide, and butanediol in that order. With continued stirring, mix paraaldehyde and dioxane and add surfactant. The resulting composition is used by filtration with 400 mesh. The viscosity of this composition and the addition or subtraction of a solid are adjusted by adding or subtracting polyvinyl alcohol, pure water, etc. according to the distribution density of a fluorescent film.

In addition, the total content of plasticizer is limited to 20-50W / V%.

When the content of the plasticizer is less than 20W / V%, the fluorescent film is easily dried, and the adhesion density is lowered. On the contrary, when the content of the plasticizer is more than 50W / V%, the drying is not good, and thus a pattern is not formed.

In addition, the above-mentioned composition is used as it is when the red and blue fluorescent film is applied, but in the case of a rust fluorescent film, a binder may be added to increase the adhesion to the glass surface.

At this time, the binder is used by using the US DuPont Ludox AM in the range of 0.5-5%.

The method of forming a fluorescent surface as the composition is carried out as shown in FIG.

The composition is applied to the inner side of the face 2 to form the first photosensitive film 4. Subsequently, the green fluorescent film mask 6 is mounted on the face 2 and exposed. Since the exposed portion of the first photosensitive film 4 has adhesiveness and insolubility in water, when the phosphor powder is sprayed, a rust fluorescent film 8 is formed.

Since the content of the plasticizer in the composition is 20-50W / V%, the adhesion density of the phosphor is considerably high.

Subsequently, the over-dispersed phosphor is recovered by a suitable collecting means such as a vacuum inhaler and washed with pure water to remove residual phosphor powder so that subsequent color residue does not occur.

Through the above process, the green fluorescent film pattern 8 ′ remains on the inner surface of the face 2. This is again treated with boric acid water so that the phosphor pattern shrinks and sticks. In the present invention, boric acid water was used as a 2.5% solution. The red and blue fluorescent film patterns are formed using the same composition as they are and are formed in the same process as the formation of the green fluorescent film pattern.

An enlarged image of the fluorescent film pattern thus obtained is shown in FIG. 2.

3 is an enlarged photograph of the fluorescent film pattern obtained by the conventional slurry coating method, and it can be seen that the stripe is coarse with the naked eye in FIG.

As described above, the present invention exhibits an advantage of providing a color cathode ray tube of highly improved image quality because the fluorescent film pattern is remarkably ordered and clearly formed.

Claims (5)

10-50% pure, 5-30% polyvinyl alcohol, 0.5-5% dichromate, 0.5-10% diethylene glycol, 0.5-5% ethylene glycol, 0.5-10% urea, 0.5-5% acetamide, butanediol A photosensitive resin composition for color cathode ray tubes comprising a composition ratio of 0.5-10%, paraaldehyde 0.5-5%, dioxane 0.5-5%, and surfactant 0.5-5%. The photosensitive resin composition for color cathode ray tubes according to claim 1, wherein the total amount of diethylene glycol, ethylene glycol, butanediol, paraaldehyde and dioxane is in a range of 20-5 W / V%. In forming red, blue, and green fluorescent film patterns of color cathode ray tube, pure 10-50%, polyvinyl alcohol 5-30%, potassium dichromate salt 0.5-5%, dieethylene glycol 0.5-10%, ethylene glycol 0.5 -5%, urea 0.5-10%, acetamide 0.5-5%, butanediol 0.5-10%, paraaldehyde 0.5-5%, dioxane 0.5-5%, surfactant 0.5-5% After coating and drying on the inner surface of the face of the color cathode ray tube, irradiating ultraviolet rays through a fluorescent film mask to expose only a predetermined portion, and then spreading the phosphor powder on the inner surface of the face and collecting the excess phosphor powder by the collecting means, A method of forming a fluorescent film of a color cathode ray tube, characterized by shrinking and fixing the fluorescent film pattern formed by washing the inner surface of the face with pure water with boric acid water. 4. The method for forming a fluorescent film of a color cathode ray tube according to claim 3, wherein boric acid is a 2.5-10% solution. The method for forming a fluorescent film of a color cathode ray tube according to claim 3, wherein the excessively dispersed phosphor powder is collected by vacuum suction.

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