JP2000192036A - Etching agent and method for forming pattern film using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a pattern with a distinct border to be formed on the surface of a metal oxide coating film mainly comprising silica by using an etching agent comprising a paste or a water solution containing a specified amount of an alkaline compound. SOLUTION: This etching agent contains 3-60 wt.% at least one alkaline compound selected from among sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, etc., together with glycerin and at least one inorganic powder selected from among cerium oxide, lanthanum oxide, aluminum oxide, etc., having a particle size of 1 μm or lower and is a paste or a water solution adjusted to a viscosity of 0.01-4 P. The etching agent is applied to a metal oxide coating film which mainly comprises silica and contains a colorant dispersed therein and comprising an oxide of a transition metal such as Co, Mn, or Cr; then, the substrate coated with the film is heated at 60-300 deg.C for 30-120 sec or is left standing at room temperature for at least 2 hr to etch the coating film; and the substrate is washed with water to remove the film, thus forming a patterning.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an etching agent and an etching agent useful for patterning a metal oxide film coated on a transparent substrate such as a glass plate used for architectural, industrial and automotive uses. The present invention relates to a method for forming a pattern film using the method.

[0002]

2. Description of the Related Art In recent years, for example, in glass for architectural or automobile use, ultraviolet shielding, infrared shielding, visible light reflection,
For the purpose of electromagnetic wave shielding, decoration, privacy protection, etc.
High-performance colored metal oxide-coated glass in which a coating made of various colored metal oxides or the like is formed on the glass surface has been widely used. In order to add another function to the colored film, the colored metal oxide-coated glass may be provided with a patterning portion for giving a part of the colored film a different color tone or making it non-colored. It is becoming.

For example, in the case of a recent automobile rear glass, in a vehicle using a glass in which a rear metal rear glass is coated with a metal oxide film having a deep color in order to protect privacy inside the vehicle, a driver applies a brake. In order to notify the rear vehicle of the step, a stop lamp warning lamp is often installed inside the rear glass. However, when the above-described dark glass is used for the rear glass, even if the stop lamp is turned on, the visibility of the stop lamp from the rear vehicle deteriorates. In order to enhance the performance, it is possible to pattern a non-film-coated portion on a part of the dark-colored metal oxide-coated glass, thereby increasing the transmittance when the stop lamp is turned on, and improving the visibility from behind. Is being done.

Further, in the case of architectural glass, it has been practiced to pattern a glass with a colored film for decoration such as an opening of a building or a partition of a store or the like, and to bring out a more decorative effect.

Many conventional methods for patterning a metal oxide film relate to the formation of a pattern film by etching removal. For example, a method of etching a tin oxide thin film having a resist pattern formed thereon using a mixed aqueous solution of hydrochloric acid and nitric acid. JP-A-8-81787 discloses a method of forming a transparent electrode having a fine pattern from an ITO thin film formed on a glass substrate by sputtering using a mixed acid of hydrobromic acid and phosphoric acid. JP-A-153332, JP-A-61-91042 as a method of forming fine irregularities by etching the surface of an inorganic oxide thin film such as silica or titania formed on a glass surface with hydrofluoric acid, and adhering to a substrate. A desired portion of the metal oxide film is coated with an aqueous solution containing at least one of sulfuric acid, nitric acid, hydrochloric acid and phosphoric acid in an amount of 4% by weight or more. Removed conductivity, color properties, JP as a method for imparting decorative mirror effect, etc. 57-1403
No. 39, as a method of forming a dry gel film obtained from a mixture of titanium alkoxide and silicon alkoxide on a plate glass substrate, screen printing an aqueous paste on the film, and eluting unnecessary portions by washing after heating at low temperature. Japanese Patent Publication No. 1-151238 is known.

[0006]

However, the above-mentioned Japanese Patent Application Laid-Open Nos. 8-81787 and 7-153332 disclose the above problems.
JP, JP-A-61-91042, JP-A-57-91042
The etching with an acid described in Japanese Patent No. 140339 or the like is not preferable because it causes severe corrosion of the apparatus and makes it difficult to form an etching agent into a paste. In addition,
When glass is used as the substrate in the case of hydrofluoric acid, the glass may be eroded. Also,
The method disclosed in Japanese Patent Publication No. 1-151238 has a problem that etching becomes difficult when the ratio of silicon alkoxide to titanium alkoxide is increased.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above points, and utilizes a property in which a silica film is soluble in a hot alkali to obtain a specific concentration of sodium hydroxide or potassium hydroxide. An etching agent consisting of a paste or an aqueous solution containing an alkaline salt of the above, and the etching agent is applied to obtain a desired pattern film, which is transmitted through a metal oxide film formed on the surface of a transparent substrate such as a glass plate. Patterning method capable of patterning with control of differences in various functions such as reflectance, reflectance, and color tone by a simple method at a low cost and capable of sharpening the boundary between a patterning portion and a metal oxide film portion. The purpose is to provide.

[0008] That is, the present invention provides an alkaline salt
The present invention relates to an etching agent for a metal oxide film surface containing silica as a main component, comprising a paste-like or aqueous solution composition containing from 60 to 60% by weight.

Further, the present invention provides an etching agent comprising a paste or an aqueous solution containing 3 to 60% by weight of an alkaline salt on a part of a surface of a metal oxide film mainly composed of silica formed on a substrate. The present invention relates to a method for forming a pattern film, characterized by forming a pattern portion by removing the coating at a portion where the etching agent is applied by heating or leaving at room temperature to wash with water after application.

The etching agent of the present invention preferably contains at least one of glycerin and inorganic fine powder, and the alkaline salts contained in the etching agent include sodium hydroxide, potassium hydroxide, calcium hydroxide, It is preferably at least one alkaline salt of lithium hydroxide, barium hydroxide, lanthanum hydroxide, and magnesium hydroxide.

The metal oxide film containing silica as a main component contains Co, Mn, Cu, Cr, Fe, Ni
It is preferable that a colorant composed of at least one transition metal oxide of a transition metal is dispersed, and the coating is more preferably made of silicon alkoxide or silica sol as a starting material.

Further, the substrate coated with the etching agent can be etched sharply by heating the substrate at a temperature of 60 to 300 ° C. for 30 to 120 seconds or by leaving it at room temperature for 2 hours or more.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described.

The metal oxide film containing silica as a main component of the present invention is formed by a dry method such as a vacuum evaporation method, a sputtering method, a CVD method, or a wet method such as a sol-gel method or a spray pyrolysis method. The method for forming the film is not limited. For example, in the case of the sol-gel method, Co, M is contained in a silica raw material such as silicon alkoxide or silica sol.
n, at least one of transition metals of Cu, Cr, Fe, Ni
A colored metal oxide film in which a coloring agent composed of a seed transition metal oxide or the like is mixed and dispersed can be used for protecting privacy of glass for vehicles and for decoration of architectural glass. In addition, the metal oxide film containing silica as a main component, silica alone or silica to titania,
A composite oxide film with silica can be formed by adding a metal oxide such as alumina and zirconia.

[0015] The etchant used in the present invention is an alkaline salt comprising at least one of sodium hydroxide, potassium hydroxide, calcium hydroxide, lithium hydroxide, barium hydroxide, lanthanum hydroxide and magnesium hydroxide. The concentration of alkaline salts contained as a main component and contained in the etching agent is limited to the range of 3 to 60% by weight, and if the concentration is less than 3% by weight, desired etching performance cannot be obtained. If it exceeds, gelation or foaming occurs when glycerin is added.

The glycerin contained in the etching agent has a moisturizing effect of preventing sodium hydroxide and the like from being easily dissolved in the etching agent and preventing the etching agent from drying during the coating operation, and a fluidity suitable for applying the etching agent. For this reason, it is preferable to use it when forming a film by screen printing, but it is not always necessary to use it when using another film forming method.

As the alkaline salt used in the present invention, any alkaline salt may be used as long as it shows alkaline in an aqueous solution. In particular, sodium hydroxide is inexpensive and easily available, and a small amount exhibits strong alkaline. It is preferably used because it is sharply etched.

The etching agent contains inorganic fine powder such as cerium oxide, lanthanum oxide, aluminum oxide, or a combination of two or more of barium sulfate, particularly for adjusting viscosity. Is preferred. The viscosity of the etching agent is 0.01 to 4
When it is in the range of 00p (poise), film formation is easy.

The inorganic fine powder contained in the etching agent is effective for adjusting the viscosity in accordance with the application method and as a fixing agent after application, and has a particle size of 1 μm or less, which does not easily damage the glass substrate when removing the etching agent. Fine particles can be used. In particular, when applying by screen printing, excellent paste rheological properties can be obtained by using a commercially available mixture of cerium oxide and lanthanum oxide as a polishing agent, MIRAKE A.

The method of applying the etching agent to the surface of the metal oxide film containing silica as a main component includes, for example, a screen printing method, a brush coating method, a spray method, a roll coating method, a spin coating method, and a flexographic printing method. It is not something to be done. After applying the etching agent, the coating is etched (eluted) by heating the substrate coated with the etching agent at a temperature of 60 to 300 ° C. for 30 to 120 seconds or by leaving it at room temperature for 2 hours or more, and then washing with water. This makes it possible to completely and easily remove the coating on the etching agent-applied portion, and to form a patterned portion from which the film has been removed on the metal oxide coating surface.

The temperature of the substrate on which the etching agent is applied is 6
Heat at 0-300 ° C for 30-120 seconds or at room temperature for 2
The reason for leaving for more than 60 hours is that the desired etching performance cannot be obtained if the temperature is less than 60 ° C. for 30 seconds or less than 2 hours at room temperature, and if the temperature exceeds 300 ° C. for more than 120 seconds, the etching agent adheres strongly to the glass substrate. This is because it is difficult to remove.

As the transparent substrate of the present invention, glass is preferable in terms of heat resistance, light transmittance and the like. If it is a transparent glass, it may be colorless or colored. That is, for example, blue, bronze, gray or green glass may be used, and especially for automotive window materials, the heat ray / ultraviolet absorption performance is improved in blue or gold color, green color, especially green or gold color tone. It is more preferable if it is easy to obtain. In addition to being able to be used as a single plate, glass with a functional film such as ultraviolet blocking glass or heat ray reflective glass, double or laminated glass or tempered glass or strengthened glass, bent glass,
It goes without saying that it can also be used as glass with a glass antenna. Further, the transparent substrate is not particularly limited, such as a glass substrate and a plastic substrate.

In addition, applications include fronts for vehicles,
Various types of glass for side, rear, sunroof etc.
There is no particular limitation on mirrors or industrial use. Hereinafter, an embodiment of the present invention will be described.

[0024]

The present invention will be described below in detail with reference to examples. However, the present invention is not limited to such an embodiment.

[0025]

Example 1 Coating of a Colored Metal Oxide Film An inorganic pigment dispersion in which a CuO—Fe ₂ O ₃ —Mn ₂ O ₃ type inorganic pigment was dispersed in ethanol at a concentration of 18.5%, and a SiO ₂ equivalent amount A mixture of methanol and silica sol solution dispersed in ethanol at 16.0 wt% was mixed with CuO.
-Fe ₂ O ₃ -Mn ₂ O ₃ -based inorganic pigment weight and silica sol S
A solution having a ratio of iO ₂ conversion amount of 1.00 and a total solid content of 17.3 wt% was prepared. (Viscosity: 5mPa.
s) Next, the film forming speed was set to 1.00 m by the dipping method.
A glass substrate having a size of 100 mm x 100 mm x 100 mm was coated on the entire surface of one side of the glass substrate at a rate of m / sec (the non-coated side of the substrate was masked with a masking film). A colored coating made of a colored metal oxide was covered.

With respect to the obtained glass with a colored coating portion,
The film thickness was measured. The thickness of the film was measured by using a surface shape measuring device (Dektak 3030, manufactured by Sloan Co.), and a part of the film was scraped off immediately after coating with a cutter, and the step was measured by contact scanning with a needle. 330n
m.

Preparation of Etching Agent and Etching 21.0 wt% of sodium hydroxide, 13.0 wt% of water, 7.0 wt% of glycerin, MIRAKE A (manufactured by Mitsui Mining & Smelting Co., Ltd.) 5
9.0 wt% was sufficiently mixed and stirred to prepare a paste-like etching agent having a viscosity of 200 p. Paste 18
Using a 0-mesh screen made of Tetron, a squeegee blade with a Shore hardness of Hs60 is used to apply about 2 mm on the colored film.
Printing was performed at a thickness of 0 μm. After printing, the glass substrate was dried so that the temperature reached 100 ° C. in 30 seconds, and then washed with water to remove the etching agent. As a result, the colored silica coating was eluted only in the portion where the etching agent was applied, and a colored silica coating in which a patterned portion was clearly formed was obtained.

[0028]

Example 2 In the same manner as in Example 1, a paste-like etching agent was screen-printed on the colored silica coating, and then left standing at room temperature (25 ° C.) for 2 hours. I washed it off. As a result, the colored silica coating was eluted only in the portion where the etching agent was applied in the same manner as in Example 1, and a colored silica coating on which a clear patterned portion was formed was obtained.

[0029]

Example 3 As in Example 1, 10.0% by weight of sodium hydroxide, 80.0% by weight of water and 10.1% of glycerin were formed on the colored film.
A mixture sufficiently mixed and stirred at 0 wt% was applied by air spray. After the application, the glass substrate was dried such that the temperature of the glass substrate reached 100 ° C. in 30 seconds. After drying, the substrate was washed with water to remove the etching agent. As in Example 1, the colored silica film was eluted only at the portion where the etching agent was applied, and a colored film with clear patterning was obtained.

[0030]

Comparative Example 1 Compared with Example 1, the composition of the etching agent was 2.5 wt% of sodium hydroxide, 23.5 wt% of water,
Example 1 was prepared by changing the glycerin to 16.2 wt% and the mille A (Mitsui Metal Mining Co., Ltd.) to 57.8 wt%.
The mixture was sufficiently mixed and stirred in the same manner as described above to obtain a paste-like etching agent having a viscosity of 180P. When the etching performance was examined in the same manner as in Example 1, the colored silica film was not completely removed but remained in an uneven state.

[0031]

Comparative Example 2 Compared with Example 1, the composition of the etching agent was 61.0% by weight of sodium hydroxide and 30.0% by weight of water.
% And glycerin 9.0 wt%,
The mixture was sufficiently mixed and stirred in the same manner as in Example 1. As a result, the etching agent gelled and fluidity that could be applied to the colored film was not obtained.

[0032]

According to the present invention, a metal oxide film having a sharp patterning portion which can be suitably used for architectural and vehicle window glass can be easily stabilized by a relatively simple method such as screen printing. In addition, there is an advantage that a pattern film capable of sharpening the boundary between the patterning portion and the metal oxide film portion can be obtained.

Claims (5)

[Claims] 1. An etching agent for a metal oxide coating surface containing silica as a main component, comprising a paste or aqueous composition containing 3 to 60% by weight of an alkaline salt. 2. A method according to claim 1, wherein the surface of the metal oxide film containing silica as a main component formed on the substrate is partially coated with an alkaline salt in an amount of 3 to 60 parts.
After applying an etching agent consisting of a paste or an aqueous solution containing by weight, the film is heated or allowed to stand at room temperature and washed with water to remove the coating on the portion where the etching agent is applied and form a pattern portion. Method for forming a patterned film. 3. The method according to claim 2, wherein the etching agent contains at least one of glycerin and inorganic fine powder. 4. A metal oxide film containing silica as a main component,
4. The pattern film according to claim 2, wherein a colorant comprising at least one transition metal oxide of transition metals of Co, Mn, Cu, Cr, Fe and Ni is dispersed in the coating. Formation method. 5. The method according to claim 2, wherein the substrate coated with the etching agent is heated at a temperature of 60 to 300 ° C. for 30 to 120 seconds or left at room temperature for 2 hours or more. Method for forming a pattern film.