JP2608535B2 - Amber colored borosilicate glass - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an amber-colored borosilicate glass used for ampoules, bottles and the like for medicines requiring light-shielding properties.

[Prior art and its problems] In general, borosilicate glass is used as an ampoule tube or the like for enclosing a medicinal solution, and BaO, Al ₂ O ₃ , CaO, etc. are used to improve chemical durability. but also Na ₂ O in order to improve the meltability and workability, K alkaline component such as ₂ O is contained, further glass such as an ampoule tube light shielding property is required TiO ₂ and Fe ₂ O _3, etc. Is added.

The light-shielding glass is required, the light-shielding properties prescribed in the Japanese Pharmacopoeia, that is, the light transmittance when measured at a wavelength interval of 20 nm at 290 to 450 nm 50% or less,
It has a light-shielding property of 60% or more in each of 590 to 610 nm, and has sufficient chemical durability against medicinal chemicals. For example, an alkali elution amount of 0.02N sulfuric acid by a test method defined by the Japanese Pharmacopoeia is required. Conditions such as consumption of 0.30 ml or less and iron elution of 0.5 ppm or less must be satisfied.

However, the amber-colored borosilicate glass composed of the above components has a low heat ray transmittance because a coloring component such as TiO ₂ or Fe ₂ O ₃ is added, and as a result, the interface temperature between the glass and the refractory at the time of melting or molding is sufficient. The barium component in the glass and the refractory react to generate barium feldspar crystals,
Devitrification due to BaO is easily generated in the glass tube forming process.

More generally, the specific gravity increases when a coloring component such as TiO ₂ , Fe ₂ O ₃ or the like is contained in the glass, and BaO, CaO, but the glass composed of the above components is compared with a color-oriented transparent glass containing no coloring component. When the specific gravity of the glass is increased, when amber is changed from amber-colored borosilicate glass to colorless and transparent borosilicate glass or vice versa in a continuous glass melting furnace, the defect generation period due to the cloth change becomes longer and the production volume increases. There is a disadvantage that it decreases.

[Object of the Invention] The present invention can suppress the generation of barium feldspar crystals during melting of glass, and can reduce the specific gravity of glass to 2.35 to 2.35.
The purpose is to provide an amber-colored borosilicate glass that has a high yield of fabric replacement with colorless and transparent borosilicate glass due to its small size of 2.37, and has excellent light-shielding properties, chemical durability, workability, and meltability. is there.

[Constitution of the Invention] The amber-colored borosilicate glass of the present invention is expressed in terms of weight percentage.
_{SiO 2 67.0~70.0, B 2 O 3} 9.0~12.0, Al 2 O 3 5.0~8.0, Na 2 O
_{5.0~8.0, K 2 O0.2~3.5, CaO0.1~2.5,} TiO 2 1.5~4.0,
Consists Fe ₂ O ₃ 0.4~1.0, preferably SiO ₂ from 67.5 to 69.5, B
₂ O ₃ 9.5 to 11.5, Al ₂ O ₃ 5.5 to 7.5, Na ₂ O 5.5 to 7.5, K ₂ O 1.0
~3.0, CaO0.3~2.0, TiO ₂ 2.0~3.5, consists Fe ₂ O ₃ 0.5~0.9, essentially contains no BaO, specific gravity, characterized in that it is from 2.35 to 2.37.

The amber-colored borosilicate glass of the present invention is essentially made of BaO
Since barium is not contained, barium feldspar is not generated when the glass is melted even when a coloring component is contained, and has the same specific gravity as colorless and transparent glass.

The reasons for limiting the content of each component of the glass of the present invention as described above are as follows.

SiO ₂ is the main glass-forming oxide, but if it is more than 70.0%, the meltability of the glass will be poor, and if it is less than 67.0%, the chemical durability will be poor and the glass components will be easily mixed into chemicals. Become.

B ₂ O ₃ improves the melting property of the glass, but if it is more than 12.0%, the chemical durability deteriorates, and if it is less than 9.0%, the above effects cannot be obtained, and the melting property of the glass deteriorates.

Al ₂ O ₃ suppresses the devitrification of the glass and improves the chemical durability. However, if it is more than 8.0%, the meltability of the glass is deteriorated, and striae and bubbles are easily generated. If the amount is small, the chemical durability becomes poor.

Na ₂ O has the effect of improving the melting property of glass and improving the coefficient of thermal expansion. However, if it is more than 8.0%, the chemical durability is reduced and the coefficient of thermal expansion is too high, and the processed glass is damaged. When the content is less than 5.0%, the above effect cannot be obtained.

In addition, the chemical durability is improved by replacing a part of Na ₂ O with K ₂ O, but when K ₂ O is more than 3.5%, the viscosity of the glass is increased and the melting property is deteriorated, and when less than 0.2% Does not provide the above effect.

CaO improves the melting property and chemical durability of the glass, but if it is more than 2.5%, the thermal expansion coefficient becomes too high and the specific gravity becomes large, and if it is less than 0.1%, the above effects cannot be obtained.

TiO ₂ is used as a coloring component and has the effect of lowering the light transmittance at wavelengths of 290 to 450 nm. However, if it is more than 4.0%, TiO ₂ devitrification tends to occur, and if it is less than 1.5%, the above effect is obtained. Can not be obtained.

Fe ₂ O _{3 is} also used as a coloring component, but if it is more than 1.0%, the light transmittance at a wavelength of 590 to 610 nm is reduced, and the amount of iron eluted increases, making it easier to mix in chemicals.
%, The light transmittance at a wavelength of 290 to 450 nm increases and the light-shielding property decreases.

EXAMPLES The present invention will be described below based on examples.

The table shows the compositions of the glass of the present invention (samples Nos. 1 to 4) and the glass of the comparative example (samples Nos. 5 and 6), the thermal expansion coefficient, specific gravity, softening point, working point, and precipitation of barium feldspar crystals of each sample. It shows temperature, alkali elution amount, iron elution amount, and light transmittance.

The sample of No. 5 is a conventional amber-colored borosilicate glass containing BaO, and the sample of No. 6 is a colorless and transparent borosilicate glass containing BaO.

The precipitation temperature of barium feldspar crystals in the table is as follows: put glass and silyminate refractory pieces in a platinum boat, melt them at 1300 degrees for 5 hours, and heat them at 1300 degrees in an electric furnace with a temperature gradient.
The maximum temperature at which barium feldspar crystals precipitated at the interface between the glass and the refractory was held for 72 hours.

The alkali elution amount was measured by the alkali elution test according to the Japanese Pharmacopoeia General Test Method for Glass Container for Injection Test, the iron elution amount was measured by the iron elution test, and the light transmittance was measured by the light-shielding test.

As can be seen from the table, since the barium feldspar crystal does not precipitate in the glass of the present invention, no devitrification due to BaO is generated in the tube forming process of the glass, and the specific gravity is lower than that of the sample No. 5, and it is colorless and transparent. As the glass is the same as the sample No. 6, the yield of fabric change is high.

[Effect of the Invention] The amber-colored borosilicate glass of the present invention has no devitrification due to BaO in the tube forming process, has a high fabric replacement yield, and has a light-shielding property prescribed in the Japanese Pharmacopoeia. Since it satisfies the properties and chemical durability, and is excellent in workability and meltability, it is suitable as an ampule tube for enclosing a medicinal liquid or glass for a bottle.

Claims (2)

(57) [Claims] 1. A SiO ₂ 67.0-70.0 in weight percent, B ₂ O ₃ 9.0~1
_{2.0, Al 2 O 3 5.0~8.0,} Na 2 O5.0~8.0, K 2 O0.2~3.5, CaO
0.1~2.5, TiO ₂ 1.5~4.0, consists Fe ₂ O ₃ 0.4~1.0, essentially contains no BaO, amber colored borosilicate glass specific gravity, characterized in that a 2.35 to 2.37. (2) SiO ₂ 67.5-69.5, B ₂ O ₃ 9.5-1 in weight percentage
_{1.5, Al 2 O 3 5.5~7.5,} Na 2 O5.5~7.5, K 2 O1.0~3.0, CaO
0.3~2.0, TiO ₂ 2.0~3.5, consists Fe ₂ O ₃ 0.5~0.9, essentially contains no BaO, specific gravity of Claims paragraph 1, wherein it is 2.35 to 2.37 Amber colored borosilicate glass.