JPH0432012B2 - - Google Patents

Description

[Detailed description of the invention]

Purpose of the Invention Industrial Field of Application The present invention relates to a dark green glass, particularly a glass having low transmittance in the near ultraviolet to visible short wavelength range (near 380 to 550 nm) and having the color tone of conventional green glass. Regarding. Conventional technology Conventional dark green glass that absorbs ultraviolet rays, that is, Y (brightness) 30 to 40% and λd (dominant wavelength) 552 to 558 m according to the CIE (International Commission on Illumination) method when converted to a thickness of 10 mm.
When producing glass with a color tone range of 58 to 74% μ, Pe (stimulus purity), the applicant's patent (Japanese Patent Publication No. 38
As seen in -16016 UV-blocking green glass), the coloring element was mainly chromium, with copper and cobalt added to adjust the hue. Problems to be Solved by the Invention In recent years, ultraviolet-blocking green glass as seen in the above-mentioned applicant's patent has been developed to
This has become unsatisfactory from the perspective of protecting beverages. In other words, it lowers the transmittance from the near-ultraviolet region to the visible region of around 400 nm to 550 nm,
Moreover, there has been a growing demand for glass to maintain its traditional green (emerald green) hue. When attempting to manufacture glass that satisfies this requirement using conventional manufacturing methods using chromium, copper, and cobalt, the colorant concentration (the total amount of chromium, copper, and cobalt) becomes extremely high, making it difficult to melt the glass. In other words, increasing the amount of colorant impedes the transmission of heat rays through the glass, preventing the temperature of the glass in areas far from the heat source from rising, leading to problems such as an increase in stone bubbles and devitrification. Means for Solving the Constituent Problems of the Invention The present invention has been made in order to solve the above-mentioned problems of the conventional art.
_Cr2O3 from 0.12 _to 0.48%, NiO from 0.03 to 0.12%,
CuO from 0.01 to 0.16%, _Co3O4 from _0.001 to 0.02%
The color tone is CIE display brightness (Y) = 0.5 to 15%, dominant wavelength (λd) = 550 to 562 nm,
Pertains to green glass with a concentration of excitation purity (Pe) = 80% or more. 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.
There is a strong demand for lowering the transmittance in the vicinity of m ~ 550 nm, but conventional green glass using chromium, copper, and cobalt as colorants is called dark green glass, that is, according to the CIE standard, and the glass thickness is 10 mm. , Y=0.5~15%, λd=550~
To obtain glass with 562nm and Pe=80% or more
The total amount of Cr ₂ O ₃ , CuO, Co ₃ O ₄ is 0.4 to 1.1 wt%
It was necessary to make it moderate. The present invention suppresses the use of chromium by using nickel in addition to conventional chromium, cobalt, and copper as colorants, and increases the colorant concentration.
That is, it was possible to produce dark green glass with a total amount of Cr ₂ O ₃ , NiO, CuO, and Co ₃ O ₄ of 0.2% to 0.5%, about half of the conventional amount. Examples The color tones and glass compositions according to the CIE glass indication (glass thickness equivalent to 10 mm) of the first to fifth examples of the dark green glass of the present invention are shown in Tables 1 and 2 along with those of conventional ultraviolet absorbing green glass. show.

【table】

[Table] The amount of coloring agent in conventional UV-absorbing green glass shown in Table 2 is 0.146% Cr ₂ O ₃ and 0.041% CuO, but in addition to these, Co ₃ O ₄ is used as a coloring agent. In order to obtain the dark green glass of the present invention, the total amount of colorant will necessarily be 0.4 to 1.1wt% as mentioned above, and the increase in colorant in the furnace will reduce the heat ray transmission of the glass. This can cause various problems, such as blocking the heat source, or preventing the temperature of glass in areas far from the heat source from rising. In the glass of the above example, by adding NiO to the conventional colorant, the total amount of all colorants from Cr ₂ O ₃ to Co ₃ O ₄ is within about 0.2 to 0.49%. . Effects of the Invention As seen in the above examples, the glass of the present invention is easy to manufacture because only a very small amount of coloring agent is used. When compared with the transmittance curve of glass, the glass of the present invention has a significantly higher transmittance than conventional ultraviolet-absorbing green glass over all wavelengths from the near-ultraviolet region to the short wavelength side of the visible region (wavelengths of 380 to 550 nm). It is getting lower. Therefore, this food and drink container prevents the contents from deterioration and deterioration due to various types of light rays and significantly improves the shelf life of food and drink, and its industrial effects must be considered to be extremely great.

[Brief explanation of drawings]

The drawing is a graph (converted to a glass thickness of 10 mm) showing the relationship between the wavelength and the transmittance of the glass of the present invention and the conventional green glass, that is, the transmittance curve. 1...Glass of Example 1, 2...Glass of Example 2, 3...Glass of Example 3, 4...Example 4
5...Glass of Example 5, 6...Conventional green glass.

Claims (1)

[Claims] 1 Cr ₂ O ₃ as a coloring element in glass from 0.12
0.48%, NiO from 0.03 to 0.12%, CuO from 0.01
Contains 0.16% _{, Co3O4} from 0.001 to 0.02%,
The color tone is CIE display brightness (Y) = 0.5-15%,
Dominant wavelength (λd) = 550-562nm, excitation purity (Pe) = 80
% or more of dark green glass.