JPH0432013B2 - - Google Patents

Description

[Detailed description of the invention]

Purpose of the Invention Industrial Field of Application The present invention is directed to a dark green glass, particularly a glass with lower transmittance from the near ultraviolet region to the short wavelength range of the visible region (near 380 to 550 nm), and which has a conventional green glass color tone. Regarding the frit suitable for obtaining. Prior Art Conventional frits of this type used chromium, cobalt, and copper as coloring elements, but the frit addition rate was about 3%. However, the conventional green glass that is intended for this purpose has a Y (brightness) of 30 to 40% and a λd (dominant wavelength) according to the CIE (International Commission on Illumination) method when converted to a thickness of 10 mm.
It was required to fall within the color tone range of 554-558 mμ, Pe (stimulus purity) 58-74%. The applicant's patent (Japanese Patent Publication No. 38-16016 Ultraviolet Blocking Green Glass) improves the ultraviolet transmittance of this glass. Furthermore, conventional production of dark green glass has been carried out in kilns or crucibles. Problems to be Solved by the Invention At present, the ultraviolet-blocking green glass as seen in the above-mentioned applicant's patent is no longer satisfactory from the viewpoint of protecting the food contents. In other words, 400nm in the visible range
There was a strong demand to lower the transmittance in the vicinity of ~550 nm. Moreover, there is a strong demand to maintain the conventional green (emerald green) color tone of the glass. In addition, with the recent diversification of product types, the production of dark green glass in a highly mobile colorant floor is extremely advantageous and has become a common demand. However, in order to obtain the dark green glass of the present invention using a conventional green glass frit, the frit addition rate had to reach as high as 50%. This presents not only the difficulty of dissolution but also many other problems, and the addition rate is never more than low. Composition of the Invention Means for Solving the Problems The present invention has been made to solve the above conventional problems, and the first invention consists of 100% silica sand, 30-90% soda ash, 12-50% lime, Borax 1-20, potassium dichromate 5-20, nickel oxide 0.5-2.5, cobalt oxide 0.1-0.4, cupric oxide 0.5-4.0, sodium nitrate sand
The second invention is a frit for producing dark green glass that has a composition range of 0.01 to 5.0 and has excellent absorption in the near-ultraviolet to visible short wavelength ranges and is added in the colorant core. ~90,
Lime 12-50, Borax 1-20, Lithium carbonate 0.001-
1. Potassium dichromate 5~20, nickel oxide 0.5~
2.5, cobalt oxide 0.1-0.4, cupric oxide 0.5-4.0,
This frit has a composition range of 0.01 to 5.0% sodium nitrate and is used in the production of dark green glass, which is added to the colorant core and has excellent absorption in the near-ultraviolet to visible short wavelength ranges. Function In recent years, glass containers have been used to store food, food, etc.
In order to more completely protect beverages, compared to conventional green glass that blocks UV rays, we have added 400n in the visible range.
Although there is a strong demand for lowering the transmittance in the vicinity of m to 550 nm, the present invention makes it possible to maintain the conventional green (emerald green) color tone of the glass. That is,
In CIE display, assuming a glass thickness of 10 mm, λd = 552 ~
558nm can be maintained. Conventional example: λd=555nm, Pe=93%, Y=1.9
% (glass thickness 10 mm) and to keep the frit addition rate to 15% or less, Cr ₂ O ₃ = 6.
% or higher concentration of frit is required, but such frit is substantially difficult to melt. The present invention suppresses the use of chromium by newly adding nickel to the conventional chromium, cobalt, and copper as a coloring agent, and the frit addition rate can be reduced to 11.5% in the example described below. Furthermore, in the case of the frit of the present invention, instead of the conventional kiln unit or crucible unit, it is added continuously in the colorant forehearth, making it possible to operate in response to product diversification and production flexibility. be. The second invention of the present application further adds lithium carbonate to the composition of the first invention, but this has a relatively high concentration of Cr ₂ O ₃ , for example, and seems to have some difficulty in dissolving the frit. It can be used in such cases. Example Example of the frit of the first invention of the present application

【table】

[Table] The color tone of dark green glass obtained by adding the flits of Examples 1 to 3 shown in the above table to the base glass flint (transparent glass) in the colorant forehearth, and the color tone of the dark green glass obtained. The amount of colorant in the glass is shown in the table below. The frit addition rate at this time, ie, the ratio of the added frit to the base glass, was 11.5%.

【table】

[Table] Effects of the invention Conventional green frit uses chromium, cobalt, and copper as coloring elements, and in order to produce the desired dark green glass using this combination, the addition rate of the frit must be increased to 50%. Must be. This is because the maximum amount of chromium that can be practically dissolved into frit glass industrially is about 3% as Cr ₂ O ₃ . In the present invention, by using nickel in addition to the conventional coloring agent mentioned above, the frit addition rate can be increased.
They were able to reduce it to 15% or less, for example, to 11.5%. Furthermore, we were able to significantly lower the transmittance in the visible range of around 400 nm to 550 nm while maintaining the color tone of conventional glass. All drawings show transmittance curves with transmittance on the vertical axis and wavelength on the horizontal axis. Figure 1 shows a glass thickness of 10 mm.
Conversion, Figure 2 shows the transmittance curve in 2.5mm conversion, but especially in the case of Figure 2, from near ultraviolet to 550nm.
A dark green glass with excellent near absorption has been obtained.

[Brief explanation of drawings]

The drawings are graphs showing the relationship between the wavelength and transmittance of glass using the frit of the present invention; FIG. 1 is based on a glass thickness of 10 mm, and FIG. 2 is based on a glass thickness of 2.5 mm. 1...Glass according to Example 1, 2...Example 2
Glass according to Example 3, 3...Glass according to Example 3, 4
...Conventional UV-absorbing green glass.

Claims (1)

[Claims] 1 Silica sand 100, soda ash 30-90, lime 12-50, borax 1-20, potassium dichromate 5-20, nickel oxide
0.5-2.5, cobalt oxide 0.1-0.4, cupric oxide 0.5
~ 4.0, sodium nitrate 0.01 ~ 5.0, added in the currant core, dark green glass manufacturing frit with excellent absorption from the near ultraviolet region to the visible short wavelength region 2 Silica sand 100, soda ash 30 ~ 90, Lime 12-50, Borax 1-20, Lithium carbonate 0.001-1, Potassium dichromate 5-20, Nickel oxide 0.5-2.5, Cobalt oxide 0.1-0.4, Cupric oxide 0.5-4.0, Sodium nitrate 0.01
A frit for producing dark green glass that has a composition range of ~5.0 and has excellent absorption in the near-ultraviolet to visible short wavelength ranges and is added to the colorant core.