JPH0563419B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing photosensitive glass articles. The photosensitive glass article obtained by the present invention is
It is used for applications such as nozzles for inkjet printers, wire guides for dot printers, insulating plates for plasma display panels, head pads for magnetic disks, fluidic devices, vacuum tube spacers, and substrates for thin and thick films.

[Prior art and its problems] Japanese Patent Publication No. 32-5080 describes SiO ₂ −Al ₂ O ₃ −
A photosensitive glass article containing trace amounts of photosensitive metals such as Ag and Au based on Li ₂ O glass is disclosed, and according to the description in the publication, this photosensitive glass article is manufactured by the following procedure. Manufactured. That is, first, photosensitive glass having the above composition is selectively exposed to light using a mask having a predetermined pattern, then developed by heat treatment to precipitate lithium metasilicate crystals, and then etched to remove the precipitated portions of the crystals. By dissolving and removing the resulting photosensitive glass article having a predetermined pattern, the entire photosensitive glass article having a predetermined pattern is exposed and heat treated, thereby obtaining a photosensitive glass article having lithium disilicate as the main crystal phase.

However, when the above-mentioned prior art method is used for manufacturing electronic or precision industrial parts, there are the following problems.

For example, when a wire guide for a dot printer or the like is manufactured using the above-mentioned conventional method, there is a problem in that the thin portion between the holes of the wire guide is damaged due to insufficient strength.

Also, when trying to manufacture insulating plates for plasma display panels, heat treatment in the final process
Since a shrinkage of ~5% occurs, it is not possible to obtain a product with the desired dimensional accuracy.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to overcome the above-mentioned drawbacks of the prior art and to provide a method for producing photosensitive glass articles having improved strength and high dimensional accuracy.

[Means for Solving the Problems] The present invention has been made to achieve the above object, and the method for manufacturing a photosensitive glass article of the present invention includes: (A) forming a predetermined pattern on photosensitive glass; (B) a step of exposing the photosensitive glass through the mask to form a latent image corresponding to the exposed portion in the photosensitive glass; (B) removing the photosensitive glass after forming the latent image; (C) etching the photosensitive glass after crystallizing the exposed portion; (C) etching the photosensitive glass after crystallizing the exposed portion; and (D) immersing the photosensitive glass after etching in a molten salt containing sodium ions and/or potassium ions to dissolve the lithium ions in the photosensitive glass and the sodium ions and ions in the molten salt. The method is characterized by including a step of ion-exchanging potassium ions.

Hereinafter, the method of the present invention will be explained in detail step by step.

Step (A) First, as the photosensitive glass used as a starting material in step (A), any glass that contains a photosensitive component and exhibits photosensitivity can be used, but for example,
SiO ₂ 55-85% by weight, Al ₂ O ₃ 2-20% by weight, Li ₂ O
5-15% by weight, SiO ₂ + Al ₂ O ₃ + Li ₂ O > 85% by weight as basic components, Au 0.001-0.05% by weight, Ag
0.001 to 0.5% by weight, Cu ₂ O 0.001 to 1% by weight as a photosensitive metal component, and further CeO ₂ 0.001 to 0.2% by weight
It is preferable to use a photosensitive glass containing as a photosensitizer.

Furthermore, as a mask used for patterning the photosensitive glass, any mask can be used as long as it has a predetermined pattern, adheres closely to the photosensitive glass, and enables selective exposure of the photosensitive glass. However, for example, a mask in which a pattern made of a chromium film is formed on a transparent glass can also be used.

This mask is brought into close contact with the photosensitive glass,
When photosensitive glass is exposed to light through a mask, nuclei consisting of photosensitive metal (Ag, Au, etc.) particles are generated in the exposed areas, forming a latent image. As this exposure means, for example, a mercury lamp, a mercury-xenon lamp, etc. are used to emit ultraviolet light for a predetermined period of time (for example, 10 seconds to 20 minutes).
Irradiation is preferred.

Step (B) The latent image photosensitive glass obtained in step (A) is then heat treated. This heat treatment is carried out at a temperature between the transition point and the yield point of the glass used. The reason for limiting the temperature to between the transition point and the yielding point is that the temperature at the end of the transition point is too low and heat treatment has no effect.
Moreover, if the bending point is exceeded, shrinkage occurs and dimensional accuracy decreases. Also, the time for this heat treatment is 30 minutes ~
It is preferable to set it as 5 hours.

By this heat treatment, lithium metasilicate crystals, for example, grow using the photosensitive metal particles present in the exposed portion (latent image) as nuclei. Since this lithium methane silicate crystal has the property of being easily dissolved in acid, etching in the subsequent step (C) can be carried out smoothly.

Step (C) The photosensitive glass obtained in step (B), in which readily acid-soluble lithium metasilicate crystals are deposited in the exposed areas, is etched with, for example, diluted hydrofluoric acid to dissolve and remove the exposed areas to obtain the desired shape. A photosensitive glass with a pattern is obtained. The concentration and temperature of dilute hydrofluoric acid, etching time, etc. are appropriately determined depending on the type of glass used and the desired degree of etching.

Step (D) The photosensitive glass having the desired pattern obtained in step (C) is then immersed in a molten salt containing sodium ions and/or potassium ions. As the molten salt, it is preferable to use sodium nitrate alone, potassium nitrate alone, or a mixture of sodium nitrate and potassium nitrate. Also, chlorides, sulfates, etc. can be used instead of nitrates. Further, the temperature of the molten salt is preferably 300 to 600°C. Further, the soaking time is preferably 1 to 16 hours.

Through this molten salt immersion treatment, lithium ions in the photosensitive glass undergo ion exchange with sodium ions and/or potassium ions having a larger ionic radius than the lithium ions, thereby creating an exchange layer, that is, a surface layer of the glass. A compressive stress layer is formed on the glass, and a photosensitive glass article with excellent mechanical strength is finally obtained.

Conventionally, an air-cooling strengthening method has been used as a glass strengthening method, but the photosensitivity of the present invention obtained by sequentially carrying out the above steps (A), (B), (C) and (D) The glass article has high mechanical strength equal to or higher than that obtained by this air-cooling strengthening method.
In addition, according to the air-cooling strengthening method, since the glass is raised to a high temperature close to its breaking point and then rapidly cooled, the glass cannot maintain its initial shape due to the high temperature and distortion, making it difficult to obtain sufficient shape accuracy. In contrast, according to the method of the present invention, the heat treatment temperature in step (B) is low, and the ion exchange temperature in step (D) is also low, so the glass can maintain its initial shape and improve shape accuracy. It's also excellent.

A photosensitive glass article with excellent strength and shape accuracy obtained through steps (A), (B), (C) and (D) in sequence,
For example, when used as an insulating plate for a plasma display panel, cells with high strength and good dimensional accuracy can be formed.

According to the method of the present invention, after carrying out the step (C) and before carrying out the step (D), (E) additionally carrying out the step of exposing the entire photosensitive glass, and then (F) ) It is also possible to carry out an additional step of heat-treating the photosensitive glass at a temperature higher than its yield point to crystallize the entire photosensitive glass.

Further, in the present invention, after performing the step (B) and before implementing the step (C), the step (E) is additionally performed, and the step (C) is performed.
The step (F) can also be additionally performed before performing (D).

In step (E) above, when the entire photosensitive glass is exposed to light, nuclei of photosensitive metal particles are generated throughout the entire photosensitive glass. This step (E) for generating nuclei of photosensitive metal particles may be performed after step (C) and before step (D), as described above, or after step (B), It may be carried out before step (C).

After this step (E), in step (F), when the photosensitive glass is heat-treated at a temperature higher than its yield point, lithium disilicate crystals mainly precipitate throughout the glass, and the glass becomes ceramic. , the mechanical strength is further increased.

Step (F) for crystallizing the entire glass is preferably carried out directly after step (E) when step (E) is carried out between step (D); When carried out between step (B) and step (C), it is preferably carried out after carrying out step (C).

By additionally performing these steps (E) and (F), the resulting photosensitive glass article can be obtained through only the above steps (A), (B), (C) and (D). The strength is further improved than that of the previous one. Therefore, even when used as a wire guide for a dot printer, for example, the thin parts between the holes will not be chipped and can be used for a long period of time.

[Examples] Hereinafter, the present invention will be further explained with reference to Examples.
The present invention is not limited to these examples.

Example 1 [Step (A) → (B) → (C) → (D)] Step (A): As glass raw materials, SiO ₂ , Li ₂ CO ₃ ,
_K2CO3 , Al(OH) ₃ , _{Na2CO3 , ZnO} , _{Sb2O3 ,}
After blending CeO ₃ , AgCl and AuCl ₃ 2H ₂ O in a predetermined ratio, it was melted at a temperature of 135°C, defoamed and clarified, and then formed into a plate shape, with the following composition, and a transition point of 550°C, A mother glass having a yield point of 600°C was obtained.

SiO ₂ 79.5 (wt%) Li ₂ O 10.2 K ₂ O 4.0 Al ₂ O ₃ 4.0 Na ₂ O 1.0 ZnO 1.0 Sb ₂ O ₃ 0.4 CeO ₂ 0.01 Ag 0.08 Au 0.003 This mother glass was cut out and 100 mm x 100 mm x 1.5
A flat plate with a diameter of mm polished on both sides was prepared, and this was used as a photosensitive glass sample plate.

Next, on the photosensitive glass sample piece obtained above,
A 1000W mercury-xenon lamp was applied to the mask with a pattern made of chrome film.
Ultraviolet rays were irradiated for 10 seconds through a mask to generate nuclei consisting of photosensitive metal Ag and Au particles in the exposed areas, forming a latent image.

Step (B): After forming the latent image, the sample piece is heat-treated at 850°C, which is a temperature between its transition point and yield point, for 3 hours to remove photosensitive metal Ag and Au particles in the exposed area (latent image). Lithium metasilicate crystals, which are easily soluble in acids, were precipitated using as a core.

Step (C): After depositing crystals on the exposed areas, the sample piece is treated with dilute hydrofluoric acid to dissolve the crystal parts that are easily soluble in acid, thereby creating a pattern corresponding to the pattern of the mask. 100mm×100mm with
A photosensitive glass sample piece of ×1.5 mm was obtained.

The obtained patterned photosensitive glass sample piece was cut out to create a plurality of patterned sample pieces (hereinafter referred to as sample piece 1a) measuring 40 mm x 5 mm x 1.5 mm. The bending strength of the obtained sample piece 1a was measured using a three-point loading method and was found to be 18 kg/mm ² .

Step (D): Next, the sample piece 1a is placed in a molten salt bath consisting of sodium nitrate and potassium nitrate (NaNO ₃ /
The final sample piece was chemically strengthened by ion-exchanging the lithium ions in the glass with the sodium and potassium ions in the molten salt by immersing it in KNO ₃ = 4/6) and performing ion exchange treatment at 350°C for 1 hour. (hereinafter referred to as sample piece 1b) was obtained.

When the bending strength of this sample piece 1b was similarly measured, it was 39 Kg/mm ² , and the strength ratio was 2.16 times that of sample piece 1a that had not been subjected to ion exchange treatment, indicating a significant improvement in strength. Ta. In addition, the initial shape was maintained and no shrinkage was observed.

Example 2 [Steps (A) → (B) → (C) → (E) → (F) → (D)] Steps (A), (B), (C): Same mother glass as Example 1 was treated in the same manner as steps (A), (B), and (C) of Example 1 to prepare a plurality of patterned sample pieces (hereinafter referred to as sample pieces 2a) measuring 40 mm x 5 mm x 1.5 mm.

The bending strength of the obtained sample piece 2a was measured by the same method as in Example 1, and it was found to be 18 Kg/mm ² similarly to the sample piece 1a.

Step (E): Next, apply 1000W of mercury to the entire sample piece 2a.
Irradiate ultraviolet light for 30 seconds with a xenon lamp,
Nuclei consisting of particles of photosensitive metals Ag and Au were generated throughout the sample piece 2a.

Step (F): Next, 860, which is higher than the yield point of the glass,
A sample piece (hereinafter referred to as sample piece 2b) in which lithium disilicate crystals were precipitated was obtained by heat treatment at ℃ for 2 hours.

When the bending strength of this sample piece 2b was similarly measured, it was 35 Kg/mm ² , and the strength ratio was 1.94 times that of sample piece 2a.

Step (D): Next, the sample piece was treated in the same manner as Step (D) of Example 1 except that the molten salt temperature was changed from 350°C to 450°C and the immersion temperature was changed from 1 hour to 16 hours. A final chemically strengthened sample piece (hereinafter referred to as sample piece 2c) was obtained by ion-exchanging the lithium ions in the glass with sodium ions and potassium ions.

When the bending strength of this specimen 2c was similarly measured, it was found to be 49Kg/ ^mm2 , and the strength ratio was
It showed a high value of 2.72 times compared to 2a (1.26 times compared to final sample piece 1b of Example 1).

Example 3 [Step (A)→(B)→(E)→(C)→(F)→(D)] Step (E) is placed between step (B) and step (C), and step
A final sample piece (hereinafter referred to as sample piece 3) was obtained in the same manner as in Example 2, except that (F) was carried out between step (C) and step (D).

This sample piece 3 had a bending strength of 49 Kg/mm ² , which was the same strength as the final sample piece 2c of Example 2.

[Effects of the Invention] As described above, according to the present invention, improvements have been made by sequentially performing the steps of selective exposure, crystallization of the exposed area by heat treatment, dissolution and removal of the exposed area by etching, and ion exchange. A patterned photosensitive glass article having strength and high dimensional accuracy is obtained.

Further, after the selective exposure step and before the ion exchange step, the strength of the photosensitive glass article can be further improved by additionally exposing the entire photosensitive glass to light and heat treating it.

Claims (1)

[Claims] 1 (A) 55-85% by weight of SiO ₂ and 5-15% by weight
(B) a step of closely contacting a mask having a predetermined pattern on a photosensitive glass containing Li ₂ O, and exposing the photosensitive glass through the mask to form a latent image corresponding to the exposed portion in the photosensitive glass; a step of heat-treating the photosensitive glass after forming the latent image at a temperature between its glass transition point and yield point to crystallize the exposed portion to obtain acid-easily soluble lithium silicate crystals; (C) exposed portion; (D) The photosensitive glass after crystallization is etched to dissolve and remove the exposed portion, and (D) the photosensitive glass after etching is immersed in a molten salt containing sodium ions and/or potassium ions to make it photosensitive. A method for manufacturing a photosensitive glass article having a pattern corresponding to the pattern of the mask, the method comprising a step of ion-exchanging lithium ions in the glass with sodium ions and/or potassium ions in the molten salt. 2 An example of carrying out the above step (C), before carrying out the above step (D), (E) additionally carrying out the step of exposing the entire photosensitive glass, and then (F) subjecting the photosensitive glass to its bending. 2. The method of claim 1, further comprising the step of thermally treating the photosensitive glass at a temperature higher than the point to crystallize the entire photosensitive glass. 3 After performing step (B) and before performing step (C), (E) additionally performing a step of exposing the entire photosensitive glass, and further after performing step (C). , before carrying out the step (D), additionally carrying out the step of (F) heat-treating the photosensitive glass at a temperature higher than its yield point to crystallize the entire photosensitive glass. Method described. 4. A photosensitive glass article obtained by the method according to any one of claims 1 to 3.