JP2000044280A - Red glass and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily develop a sharp red color in a soda lime glass at low cost without reheating and to obtain copper-red glass. SOLUTION: This red glass is produced by beating and melting a source material containing silica sand, lime, soda ash, copper oxide or metal oxide as a coloring agent, a reducing agent such as cokes, and salt cake as a clarifying agent by 0 to 0.3 kg/100 kg sand, and then forming. In this method, by specifying the salt cake as a clarifying agent to 0 to 0.3 kg/100 kg sand to suppress the sulfur content in the glass to the min., amber color in the reduced state is suppressed to develop a red color. Thus, glass having a sharp red color can be obtd. without reheating treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a red soda-lime glass which can be used as a glass bottle, tableware, vases, flat glass and the like, and a method for producing the same.

[0002]

2. Description of the Related Art Glass containing PbO, such as high-lead crystal glass, or glass containing SnO or BiO2 is added with copper as a coloring agent, melted and then reheated to uniform the particle size of the metal colloid. It is known that the so-called copper red glass is colored. The most versatile soda lime glass, such as glass bottles, tableware, vases, and flat glass, can be added with a reducing agent such as copper and coke as a coloring agent, melted and then reheated to make copper-red glass. Are known.

[0003]

For high lead crystal glass, copper red glass can be obtained by adding copper as a colorant and reheating, but the most versatile soda-lime glass requires clear copper red glass. It was very difficult to get. In soda-lime glass, copper as a colorant becomes blue when the glass is in an oxidized state, and absorbs copper red when the glass is in a reduced state, but almost becomes amber in appearance. Therefore, the glass must be brought to a neutral range within a predetermined range, and it is difficult to mix the amount of the reducing agent and the like. Further, when the glass was in a neutral state, the coloration of copper red was insufficient, and a reheating treatment was indispensable. The present invention makes it possible to produce soda lime glass in a vivid red color and inexpensively and easily, without reheating, to obtain a copper red glass.This makes it possible to use a vivid red glass for various applications. It is possible.

[0004]

According to the present invention, silica sand, lime, soda ash, copper oxide or metallic copper as a colorant, a reducing agent such as coke and a clarifying agent of 0 to 0.3 kg / 100 kg of sand are used. It is a red glass characterized by being obtained by heating and melting a raw material containing the raw material and molding.

[0005] In the production of soda-lime glass, usually, sodium sulfate (Na2SO4) of about 0.8 kg / sand 100 kg is used as a fining agent. Glauber's salt is decomposed in the molten glass to generate sulfur, but due to the presence of this sulfur and iron contained in the main raw material of soda-lime glass, copper is added as a coloring agent to reduce it (in the oxidized state, copper develops a blue color) Do)
Although the molten glass has a copper red absorption area,
It develops amber color. Therefore, the present invention limits the amount of sodium sulfate, which is a fining agent, to 0 to 0.3 kg / 100 kg of sand and minimizes the sulfur content in the glass,
It succeeded in suppressing the amber color in the reduced state and developing red. Moreover, in the present invention, clear red glass can be obtained without performing reheating treatment.

[0006] By reducing the amount of sodium sulfate as a fining agent, the removal of bubbles in the glass is hindered, but the melting time of the glass is slightly increased, and if necessary, a fining agent containing no sulfur component such as antimony oxide. The problem of air bubbles can be solved without disturbing the development of red color.

[0007] A reducing agent such as coke is added to bring the glass into a reduced state. Since there is no need to bring the concentration to neutral as in the conventional case, there is no need to strictly examine and control the amount of addition.

In addition, in the present invention, it has been discovered that it is not necessary to reheat the molten glass when the glass is colored with copper red. Usually, when coloring glass with a metal colloid, reheating treatment is often required in order to obtain a pyrosol having a particle size suitable for coloring, but in the case of the present invention, it is clear without performing this treatment. Red glass can be obtained.

[0009] Copper components such as copper oxide and metallic copper, which are coloring agents, can be mixed in advance in a batch and melted in a kiln to obtain red glass. In the kiln, flint glass (colorless transparent glass) raw material is melted. Alternatively, the mixture can be mixed with a colorant foreheart. As the copper component, copper oxide or metallic copper may be directly mixed into the main glass material, or a processed frit may be mixed.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION 100 parts of silica sand, 26 parts of lime, 32 parts of soda ash, 2.5 parts of aluminum hydroxide, 0.2 parts of coke, and 0.675 parts of cupric oxide powder are mixed together.
Stir for 0 minutes, melt in a kiln at 1450 ° C for 3 hours,
After being formed into a plate having a thickness of 4 mm, it was put into a slow cooling furnace at 600 ° C., and then allowed to cool naturally to room temperature to obtain a clear red glass. This red glass has a lightness of 9.8% and a main wavelength of 606n.
m, the stimulus purity was 86.80%, and the transmittance curve was as shown in FIG.

100 parts of silica sand, 26 parts of lime, 32 parts of soda ash
Parts, aluminum hydroxide 2.5 parts, coke 0.2 part,
1.350 parts of cupric oxide powder and 1.0 part of antimony oxide were mixed, stirred for 20 minutes, melted in a kiln at a temperature of 1450 ° C. for 3 hours, formed into a plate having a thickness of 4 mm, and then heated to 600 ° C.
And then allowed to cool naturally to room temperature to obtain a clear red glass.

[0012] Silica sand 100 parts, lime 26 parts, soda ash 32
Part, aluminum hydroxide 2.5 parts, sodium sulfate 0.
3 parts, 0.2 parts of coke, and 1.350 parts of cupric oxide powder were mixed, stirred for 20 minutes, melted in a kiln at a temperature of 1450 ° C. for 3 hours, and formed into a plate having a thickness of 4 mm. 600 ° C
And then allowed to cool naturally to room temperature to obtain a clear red glass.

[0013]

Since the present invention uses soda-lime glass as copper red glass, inexpensive copper red glass can be used for various uses such as glass bottles, tableware, vases, and flat glass. Further, in the production, a reheating treatment is not required, and the compounding amount of the reducing agent does not need to be as strict as in the past, so that red soda-lime glass can be easily produced.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a transmittance curve of red glass of an example.

Claims (4)

[Claims] A raw material containing silica sand, lime, soda ash, copper oxide or copper as a colorant, a reducing agent such as coke, and a refining agent of 0 to 0.3 kg of mirabilite / 100 kg of sand is heated and melted. Red glass characterized by obtaining 2. A material containing silica sand, lime, soda ash, copper oxide or copper as a colorant, a reducing agent such as coke, and a fining agent containing no sulfur component such as antimony oxide, is heated and melted, and is molded. Red glass characterized by obtaining 3. A raw material containing silica sand, lime, soda ash, copper oxide or metallic copper as a coloring agent, a reducing agent such as coke, and 0 to 0.3 kg of sodium sulfate as a fining agent / 100 kg of sand is heated and melted. Method for producing red glass 4. A raw material containing silica sand, lime, soda ash, copper oxide or copper as a colorant, a reducing agent such as coke, and a fining agent containing no sulfur component such as sodium antimonate, is heated and melted, and is formed. Method for producing red glass