JP5624587B2 - UV-absorbing colorless and transparent soda-lime silica glass - Google Patents

Description

  The present invention relates to an ultraviolet-absorbing colorless and transparent soda lime silica glass, and a glass container formed by molding the glass. More specifically, the present invention prevents the contents such as soft drinks and alcoholic beverages filled in the glass container from being colored, discolored, discolored or deteriorated in flavor, and the glass has no green color. The present invention relates to a UV-absorbing colorless and transparent soda-lime-silica-based glass in which the color of the beverage or the like of the contents can be clearly seen, and a glass container formed by molding the glass.

  Conventionally, glass bottles such as brown bottles, green bottles, and blue bottles have been widely used for sake and beer in order to suppress the coloring, discoloration, fading, and flavor deterioration of beverages and other contents caused by light. It has been. All of these glass containers were dark colored glass bottles and could not be used for products intended to show the color of their contents. The fact that the color of the contents of the glass container can be seen from the outside increases the value of the product and is closely related to consumers' willingness to purchase, so a transparent and colorless glass container with high brightness is required so that the contents can be seen clearly. It has been. However, many transparent and colorless glass containers with high lightness have high UV transmittance at the same time. When ultraviolet light passes through a glass container, the contents of the glass container are likely to be colored, discolored, and faded. In particular, when the contents contain a blue, red, or yellow pigment, fading due to photodecomposition of the pigment is a problem. It becomes. The content will eventually become nearly colorless as the color fades, and the commercial value will be significantly impaired.

  Moreover, in the field of architectural and vehicle glass, glass that absorbs ultraviolet rays is manufactured for the purpose of preventing sunburn, etc., but these ultraviolet absorbing glasses are colored, so that the field of view becomes slightly dark. There's a problem.

As a method for solving the above problem, the present inventors have proposed an ultraviolet-absorbing colorless and transparent soda-lime-silica glass containing V ₂ O ₅ and Se in JP-A-11-116270 (Patent Document 1). . The soda-lime-silica glass described in the document obtained by containing V ₂ O ₅ and Se in a specific ratio can solve the above-mentioned problem, but this glass is recycled to obtain a normal colorless color. When used as a cullet of transparent glass, it is colored pink due to the reduction coloration of Se, so that a problem remains from the viewpoint of recycling the cullet glass. As a glass in which Se is changed to Mn, there is an ultraviolet-absorbing colorless soda-lime glass containing V ₂ O ₅ and MnO ₂ disclosed in JP-A-52-47811 (Patent Document 2). However, this glass _is very small amounts of MnO ₂ relative to the amount of V 2 _{O 5,} it is difficult to completely decolorized coloration due V 2 _{O 5} in MnO _2. Japanese Patent Laid-Open No. 2002-249338 (Patent Document 3) discloses that the coloration of V ₂ O ₅ is erased by adding MnO ₂ to obtain a colorless and transparent ultraviolet absorbing glass. However, this glass has a high content of expensive V ₂ O _{5 and} is expensive to manufacture. For this reason, the content of V ₂ O ₅ is low, it can be produced at low cost, has a high transmittance in the visible range, and the contents can be clearly seen in stores, and ultraviolet rays are not applied to the contents in the distribution process or stores. There has been a need for a colorless and transparent UV-absorbing glass container that can avoid exposure and can be reused as a cullet for ordinary colorless and transparent glass.

JP-A-11-116270 JP 52-47811 A JP 2002-249338 A

  The present invention increases the ultraviolet absorption rate in a combustion reducing atmosphere in a glass manufacturing process on an actual industrial scale (under a low oxygen atmosphere with an oxygen concentration of about 2% or less), and obtains a highly efficient and stable decoloring effect. In the case of maintaining a high light transmittance in the visible range and making it into a container form, the contents can be seen clearly, and at the same time, the contents can be colored, discolored, discolored or deteriorated in flavor due to ultraviolet rays. An object of the present invention is to provide an ultraviolet-absorbing colorless and transparent soda-lime-silica-based glass that can be prevented and reused as a cullet of ordinary colorless and transparent glass, and a glass container formed by molding the glass.

  As a result of repeated studies to solve the above-mentioned problems, the present inventors have controlled the redox properties by controlling the content of sodium nitrate and carbon in the usual basic constituent materials of soda-lime-silica glass, and In addition, vanadium oxide, manganese oxide, antimony oxide, cobalt oxide-containing colored frit or vanadium oxide, manganese oxide, antimony oxide-containing colored frit and, if necessary, oxidized in a feeder which is an area for supplying glass to the mold. It has been found that by adding a mixture containing a cobalt-containing frit, it is possible to stably produce a UV-absorbing colorless transparent soda-lime-silica glass that has a high UV absorption rate and a high visible light transmittance and is suitable for recycling. Based on this finding, the present invention has been completed. That is, the present invention provides the following.

1. It contains vanadium oxide, manganese oxide, and antimony oxide, the vanadium oxide content is 0.02 to 0.06 wt% in terms of V ₂ O ₅ , and the manganese oxide content is 0.03 to 0.3 in terms of MnO. An ultraviolet-absorbing colorless and transparent soda-lime-silica glass characterized by 20% by weight and an antimony oxide content of 0.005 to 0.06% by weight in terms of Sb ₂ O ₃ .
2. The ultraviolet-absorbing colorless and transparent soda-lime silica glass according to 1 above, wherein the weight ratio of vanadium oxide to manganese oxide is 0.1 or more and less than 0.6 in terms of V ₂ O ₅ / MnO.
3. The ultraviolet absorbing colorless and transparent soda-lime-silica glass according to 1 above, wherein the weight ratio of vanadium oxide to manganese oxide is 0.6 or more and less than 0.9 in terms of V ₂ O ₅ / MnO.
4). The ultraviolet-absorbing colorless and transparent soda-lime-silica glass according to any one of 1 to 3 above, wherein the content of cobalt oxide is 0.0004% by weight or less in terms of CoO.
5. The ultraviolet-absorbing colorless and transparent soda-lime-silica glass according to any one of the above 1 to 4, wherein the content of SO ₃ is 0.15 to 0.30% by weight.
6). In the transmittance curve measured at a thickness of 3.5 mm, the transmittance at a wavelength of 330 nm is 20% or less, and there is no absorption in a specific wavelength region in the visible region of a wavelength of 430 to 780 nm, and the transmittance is 80% or more. , UV absorbing colorless and transparent soda lime silica glass of any one of 1 to 5 above.
7). In the transmittance curve measured at a thickness of 3.5 mm, the transmittance at a wavelength of 330 nm is 10% or less, and there is no absorption in a specific wavelength region in the visible region of a wavelength of 430 to 780 nm, and the transmittance is 80% or more. , UV absorbing colorless and transparent soda lime silica glass of any one of 1 to 5 above.
8). A glass container formed by molding the ultraviolet absorbing colorless and transparent soda-lime-silica glass according to any one of 1 to 7 above.

According to the present invention, V ⁵⁺ ions in vanadium oxide can be increased in a combustion reducing atmosphere (in a low oxygen atmosphere having an oxygen concentration of about 2% or less) in a glass manufacturing process on an actual industrial scale. UV absorption increases, and Mn ³⁺ ions in manganese oxide are also increased efficiently. As a result, highly efficient and stable decoloring effect can be achieved, and high light transmittance is maintained in the visible range. Transparent soda lime silica glass can be obtained. When the glass of the present invention is in the form of a container, the contents can be clearly seen, and at the same time, the contents can be prevented from being colored, discolored, discolored, or deteriorated in flavor due to ultraviolet rays. Moreover, the said glass of this invention can be reused as a cullet of normal colorless and transparent glass.

FIG. 1 is a graph comparing the dominant wavelengths of the glasses of Comparative Example 2, Comparative Example 3, and Examples 1-4.

In this specification, “vanadium oxide” refers to any of V ₂ O ₃ , VO _2, and V ₂ O ₅ , but the weight percentage of the content in the glass indicates all vanadium oxides contained. Is expressed as a value when V is replaced with V ₂ O ₅ . “Manganese oxide” refers to both MnO and Mn ₂ O ₃ , but the weight percentage of the content in the glass is the value when all the manganese oxide contained is replaced with MnO. It is represented by. Further, “antimony oxide” refers to both Sb ₂ O ₃ and Sb ₂ O ₅ , but the weight percentage of the content in the glass indicates that all the antimony oxide contained is Sb ₂ O ₃ . This is the value when it is replaced. Furthermore, for “cobalt oxide”, the weight percentage of the content in the glass is expressed by the value when all the cobalt oxide contained is replaced by CoO.

  Food colorants that are blue, red and yellow pigments contained in contents such as beverages packed in glass containers (for example, Food Red 104, Food Red 105, Food Red 106, Food Yellow 4) , Edible Yellow No. 5, Edible Blue No. 1, Edible Blue No. 2, β-carotene, hibiscus pigment, grape skin pigment, etc. have been investigated. In addition to light having a wavelength at which the extinction coefficient in the visible region is maximum, light having a small extinction coefficient but high energy in the near ultraviolet to visible short wavelength region, that is, light having a wavelength of 450 nm or less, particularly 300 to 400 nm, is also included. It has been elucidated that there is a great influence, and the results are consistent with the results of research on the relationship between the deterioration of various soft drinks and many alcoholic drinks other than beer and the wavelength of the light that causes them. Door has been confirmed. In other words, if the glass container is made of glass that is excellent in absorption from the near ultraviolet region to the visible short wavelength region, and has a high lightness and is almost colorless to the naked eye, the color of the contents of the container can be seen clearly. It is known that photodegradation of contents can be suppressed (Patent Document 3).

The ultraviolet-absorbing colorless and transparent soda-lime-silica glass of the present invention has such characteristics, and the content of vanadium oxide is 0.02 to 0.06% by weight in terms of V ₂ O ₅ , manganese oxide. The content of is 0.03 to 0.20% by weight in terms of MnO, and the content of antimony oxide is 0.005 to 0.06% by weight in terms of Sb ₂ O ₃ . Here, preferably, the weight ratio of vanadium oxide to manganese oxide is preferably 0.1 or more in terms of V ₂ O ₅ / MnO, for example, 0.2 or more, and preferably 0.9 For example, it may be less than 0.6.

Vanadium oxide has an action as an ultraviolet absorber and is contained mainly in the form of V ₂ O ₅ in the glass of the present invention, but does not prevent the presence of V ₂ O ₃ and VO ₂ . The content ratio of V ₂ O ₃ and VO ₂ with respect to V ₂ O ₅ changes depending on the content of SO ₃ and is not clear. However, when V ₂ O ₃ and VO ₂ increase, the glass color becomes green, and it depends on manganese. Since it is difficult to erase the color, it is preferable that these do not exist. If the content of vanadium oxide is less than 0.02% by weight in terms of V ₂ O ₅ , the ultraviolet absorption effect may be insufficient. On the other hand, if it exceeds 0.06% by weight, the production cost becomes expensive, it becomes difficult to decolorize, and there is a possibility that it will be colored green. Considering the ultraviolet absorption effect, decoloration, cost, etc. of the glass, the vanadium oxide content is more preferably 0.03 to 0.05% by weight in terms of V2O5.

Manganese oxide is due to Fe ₂ O _3, which is inevitably introduced from vanadium oxide and the usual raw materials are contained as an ultraviolet absorber, an essential component for decolorizing a yellow-green coloration of the glass, SO _3, oxide Depending on the content of vanadium and iron oxide, 0.03 to 0.20% by weight in terms of MnO is contained. Manganese oxide exists in the glass as MnO and Mn ₂ O ₃ , and the ratio is not clear, but it is Mn ³⁺ ions that have a decoloring effect. If the content of manganese oxide is less than 0.03% by weight in terms of MnO, the decoloring effect may be insufficient. On the other hand, if the content exceeds 0.20% by weight, the reddish purple coloration of excess Mn ³⁺ ions cannot be sufficiently erased even if cobalt oxide (described later) is used for erasing this, or the color disappears. Even if it can, it may reduce the brightness of the glass and impair the transparency. Considering the decoloring effect and the like, the content of manganese oxide is more preferably 0.05% by weight or more in terms of MnO, for example, 0.08% by weight or more. Moreover, it is preferable that it is 0.16 weight% or less, for example, it is good also as 0.14 weight% or less or 0.12 weight% or less.

Antimony oxide has the effect of increasing the V 5 ⁺ ion in vanadium oxide, which is effective for the ultraviolet absorption effect, and increasing the ultraviolet absorption rate. Antimony oxide also has the effect of increasing the decoloring effect by increasing the Mn ³⁺ ions of manganese oxide and shifting the dominant wavelength (λd) of the glass to the longer wavelength side by coloring magenta. The content of antimony oxide is 0.005 to 0.06% by weight in terms of Sb ₂ O ₃ . If the content of antimony oxide is less than 0.005% by weight, the decoloring effect may be insufficient. If it exceeds 0.06% by weight, reddish purple coloring of Mn ³⁺ ions may occur due to excessive oxidation. Even if it contains the later-described cobalt oxide for erasing the color, it cannot be sufficiently erased, or even if it can be erased, the brightness of the glass may be reduced and the transparency may be impaired. Antimony oxide further exhibits a decoloring effect by combining nitrate ions. In that case, the content rate of nitrate ion is 6% or less in terms of sodium nitrate, and more preferably 4 to 6% by weight.

The ultraviolet-absorbing colorless and transparent soda-lime silica glass of the present invention further contains vanadium oxide and manganese oxide in a weight ratio of 0.1 or more and less than 0.9, for example 0.1 or more and 0, in terms of V ₂ O ₅ / MnO. It is preferably contained in a weight ratio of less than .6 or a weight ratio of 0.6 or more and less than 0.9. If V ₂ O ₅ / MnO is less than 0.1, the dominant wavelength (λd) of the glass may shift to the longer wavelength side, and the glass may be colored light pink. Such a fear can be more surely removed by setting V ₂ O ₅ / MnO to 0.1 or more, and further to 0.2 or more, for example. Conversely, if V ₂ O ₅ / MnO is too large, the dominant wavelength (λd) shifts to the short wavelength side and the glass may be colored pale yellowish green, but V ₂ O ₅ / MnO is less than 0.9. Then such a fear can be eliminated. Therefore, V ₂ O ₅ / MnO can be set to less than 0.9, and may be set to less than 0.6, for example. In order to more surely obtain the colorless feeling of the glass, V ₂ O ₅ / MnO is set to 0.30 or more and less than 0.80, for example, 0.30 or more and less than 0.40 or 0.40 or more and 0.8. It is good also as less than.

Cobalt oxide has the effect of decoloring the magenta coloration due to Mn ³⁺ ions. Although the inclusion of cobalt oxide is not essential, the inclusion of cobalt oxide has the effect of reducing the stimulation purity (Pe). When the stimulus purity is reduced, the transparency of the glass increases, and the contents in the glass container appear clearer. At the same time, the dominant wavelength shifts to the short wavelength side, but the brilliance of the glass does not occur because the excitation purity is lowered. The content of cobalt oxide can be contained in an amount of 0.0004% by weight or less in terms of CoO. If the amount of cobalt oxide exceeds 0.0004% by weight, the lightness is lowered and the transparency of the glass may be impaired. Considering the transparency of glass and the like, the content of cobalt oxide is more preferably 0.00035% by weight or less in terms of CoO.

The ultraviolet absorbing colorless and transparent soda lime silica glass of the present invention may contain SO ₃ . When SO ₃ is contained, it is preferably contained in an amount of 0.15 to 0.30% by weight. SO ₃ may be the residue in the glass of the fining agent added to the raw material batch in a combination of mirabilite and carbon, so that the amount is 0.15 to 0.30% by weight. The amount of other raw material batches, oxidizing agents that control the redox properties of the frit, and reducing agents can be determined, and the atmosphere of a furnace such as a continuous melting furnace can be adjusted. When SO ₃ content in the glass is less than 0.15 wt%, the glass is biased to a reducing _side, the ratio of FeO with respect to _{V 2 O} 3, VO 2 ratio and _Fe 2 _{O 3} with respect to V 2 _{O 5} is As the ratio becomes higher and the ratio of Mn ₂ O _{3 to} MnO becomes lower, there is a possibility that green or blue tint is produced in the glass. Conversely, if the SO ₃ content in the glass exceeds 0.30% by weight, bubbles may remain in the glass. Considering prevention of light green to light blue coloring of the glass, seeds in the glass and the like, the SO ₃ content in the glass is more preferably controlled to 0.20 to 0.28% by weight.

The colored frit is preferably produced from a batch composition containing 6 parts by weight or less of nitrate ions (NO ³⁻ ) in terms of sodium nitrate in 100 parts by weight of the raw material mixture for production. However, when the nitrate ion content in 100 parts by weight of the raw material mixture for producing the colored frit is less than 1.5 parts by weight in terms of sodium nitrate, the ratio of Mn ₂ O _{3 to} MnO in the obtained glass becomes low. , There is a risk that sufficient decoloring effect cannot be obtained. Considering the decoloring effect due to Mn ³⁺ ions, the content of nitrate ions in 100 parts by weight of the raw material mixture for producing colored frit is more preferably 4.0 to 6.0 parts by weight in terms of sodium nitrate. An amount of nitrate ion which does not become more oxidizing than necessary can be contained.

The composition of the UV absorbing colorless and transparent soda-lime-silica glass of the present invention is excellent chemical durability, it is no risk of devitrification, and in consideration of the appropriate easiness of melt, SiO ₂ content 65 75 wt%, _Al 2 _{O 3} content of 0-5 wt%, CaO content of 6 to 15 wt%, MgO content of 0-4 wt%, Na ₂ O content of 10 to 17 wt%, _{K 2} O content The amount 0-4% by weight, _Fe 2 _{O 3} content of 0 to 0.08 wt%, FeO content 0-0.01 _wt%, SO 3 0.15 to 0.30 wt%, vanadium oxide _(V 2 O ₅ conversion) 0.02 to 0.06 wt%, manganese oxide content (MnO conversion) 0.03 to 0.20 wt%, antimony oxide content (Sb ₂ O ₃ conversion) 0.005 to 0.06 wt% % And cobalt oxide content (CoO conversion) 0-0.000 It is preferably 4% by weight. SiO ₂ is a glass-forming oxide and is preferably contained in an amount of 65 to 75% by weight. This is because if the content of SiO ₂ is less than 65% by weight, the chemical durability of the glass may be lowered, and if it exceeds 75% by weight, devitrification tends to occur. Considering the chemical durability and devitrification of glass, it is more preferable that SiO ₂ is contained in an amount of 68 to 74% by weight.

Al ₂ O ₃ is a glass intermediate oxide and has an effect of improving the chemical durability of the glass. The content of Al ₂ O ₃ is not essential, but when it is included, it is preferably 5% by weight or less. If the content of Al ₂ O ₃ exceeds 5% by weight, melting may be difficult. Considering the chemical durability, melting property, and the like of glass, it is more preferable to contain 1 to 4% by weight of Al ₂ O ₃ . CaO is a glass-modified oxide and has an effect of improving the chemical durability of glass and improves the meltability. CaO is preferably contained in an amount of 6 to 15% by weight. If the CaO content is less than 6% by weight, chemical durability may be insufficient. Conversely, if it exceeds 15% by weight, devitrification tends to occur. Considering the chemical durability, melting property, devitrification property, etc. of the glass, it is more preferable to contain 8 to 13% by weight of CaO. MgO is a glass-modified oxide, and has the effect of improving the chemical durability of glass as well as CaO, and improves the meltability. The content of MgO is not essential, but when it is included, it is preferably 4% by weight or less. This is because if the content of MgO exceeds 4% by weight, devitrification tends to occur. Considering the chemical durability, meltability, devitrification, etc. of the glass, it is more preferable to contain 0.1 to 3% by weight of MgO. Na ₂ O is a glass-modified oxide and has an effect of promoting dissolution of the raw material. Na ₂ O is preferably contained in an amount of 10 to 17% by weight. If the Na ₂ O content is less than 10% by weight, it becomes difficult to melt the glass. Conversely, if it exceeds 17% by weight, the chemical durability of the glass may be lowered. In consideration of the melting property and chemical durability of the glass, Na ₂ O is more preferably contained in an amount of 11 to 15% by weight.

K ₂ O is a glass-modified oxide and has the effect of promoting the dissolution of the raw material, like Na ₂ O. The content of K ₂ O is not essential, but when it is included, it is preferably 4% by weight or less. When the content of K ₂ O exceeds 4% by weight, devitrification tends to occur. Considering the melting property and devitrification property of the glass, it is more preferable to contain 0.1 to 3% by weight of K ₂ O. Fe ₂ O ₃ is a component that is inevitably generated from iron contained as impurities in the silica raw material batch of glass. It does not need to be contained in the ultraviolet-absorbing colorless and transparent soda-lime silica glass of the present invention, and is preferably not contained at all. The content of Fe ₂ O ₃ is usually 0.08% by weight or less when silica sand sold as a glass raw material is used. When the content of Fe ₂ O ₃ exceeds 0.08% by weight, it becomes difficult to ^{decolor the} yellowish green coloration due to Fe ³⁺ ions with Mn ³⁺ ions. Considering prevention of coloring of the glass and the like, Fe ₂ O ₃ is more preferably 0.06% by weight or less, and further preferably 0.04% by weight or less. FeO is a component inevitably generated in the glass melting process from iron contained as impurities in the silica raw material batch of glass. It is an unnecessary component for obtaining the ultraviolet-absorbing colorless and transparent soda-lime silica glass of the present invention, and its content is preferably 0.01% by weight or less. If the content of FeO exceeds 0.01% by weight, the glass may be bluish. In order to ensure that the glass is colorless and transparent, the content of FeO is more preferably 0.006% by weight or less, and further preferably 0.004% by weight or less.

  By setting the above composition range, in the transmittance curve measured at a thickness of 3.5 mm of the sample, the transmittance at a wavelength of 330 nm is preferably 20% or less, more preferably 10% or less, and a wavelength of 430 to 780 nm. UV-absorbing colorless and transparent soda-lime silica glass having a transmittance of 80% or more, more preferably 83% or more, still more preferably 86% or more, particularly preferably 88% or more without absorption in a specific wavelength region in the visible region. Can be obtained. If the transmittance at a wavelength of 330 nm is 20% or less, particularly 10% or less, when used as a glass container, it is possible to substantially block the penetration of ultraviolet rays that affect the contents of beverages and the like in the container, It is possible to prevent coloring and discoloration of the contents by ultraviolet rays, fading due to decomposition of the pigment, deterioration of flavor, and the like. The transmittance at a wavelength of 330 nm is more preferably 7% or less, and still more preferably 5% or less. Moreover, when it uses as a glass container as the transmittance | permeability is 80% or more without absorption of a specific wavelength range in the visible region of wavelength 430-780 nm, the contents can be shown clearly. If there is a region where the transmittance is less than 80% in the visible range of 430 to 780 nm, the transparency of the glass container may be impaired or the glass container may be colored lightly. Furthermore, when the glass of the present invention is used as a glass sheet for buildings and vehicles, it can sufficiently exhibit an ultraviolet shielding effect such as sun protection. Moreover, the ultraviolet-absorbing colorless and transparent soda-lime-silica glass of the present invention is a value calculated by conversion according to the following method when the sample thickness is 10 mm based on data obtained by measuring a sample having a thickness of 9 to 11 mm. The brightness (Y) is 80% or more, the dominant wavelength (λd) is 540 to 585 nm, and the stimulation purity (Pe) is preferably 2.2% or less. In this type of glass that does not have absorption at a specific wavelength in the visible range, if the dominant wavelength (λd) is less than 540 nm, the glass may be bluish, and conversely if it exceeds 585 nm, the glass may be reddish. . Furthermore, by controlling the content and content ratio of vanadium oxide, manganese oxide and antimony oxide in the glass and the content of cobalt oxide, the value obtained by converting the data obtained at a thickness of 9 to 11 mm to a value at a thickness of 10 mm. As a result, it is possible to obtain a UV-absorbing colorless and transparent soda-lime-silica glass having a more colorless feeling and having a brightness (Y) of 82% or more, a dominant wavelength (λd) of 540 to 575 nm, and an excitation purity (Pe) of 2.0% or less.

  In the above, the lightness (Y) at each wavelength at the reference thickness (10 mm) (Y among the tristimulus values of the object color), the dominant wavelength (λd), and the stimulation purity (Pe) are 9 to 11 mm (t1) in thickness. From the data obtained by measuring the sample of

From the converted transmittance at each wavelength at the standard thickness (10 mm) converted according to JIS Z8701-1995 (the CIE 1931 standard colorimetric system and
the CIE 1964 supplementary standard colorimetric system).

Production of the ultraviolet-absorbing colorless and transparent soda-lime silica glass and glass container of the present invention can be carried out, for example, as follows. That is, with respect to 100 parts by weight of silica sand, 25 to 36 parts by weight of soda ash, 23 to 33 parts by weight of limestone, 0.026 to 0.13 parts by weight of carbon (with a purity of 100% by weight), 1.0 to 3. A batch composition containing each raw material at a ratio of 0 part by weight was melted at 1400-1500 ° C., adjusted to 1200-1350 ° C. in a working room, and then added to vanadium oxide, manganese oxide, Add a colored frit containing cobalt, if necessary, to a colored frit containing antimony oxide or a colored frit containing vanadium oxide, manganese oxide, antimony oxide, cobalt oxide, and stir the gob. Put into a molding machine and mold into a container shape between 700-1000 ° C. The molded glass container is introduced into a slow cooling furnace to remove strain at 500 to 600 ° C., and cooled to room temperature in 30 minutes to 2 hours to obtain a product. In the case of forming a sheet glass from the glass of the present invention, a conventional method such as a casting-press method, a float method, a downdraw method, and a pulling method can be used. The carbon ratio in the batch composition is a numerical value when the carbon purity is 100% by weight. If the purity of the carbon used is different, the ratio is changed accordingly. Moreover, it is more preferable that the amount of carbon (purity 100% by weight) and mirabilite relative to 100 parts by weight of silica sand is 0.03 to 0.07 parts by weight and 1.2 to 2.0 parts by weight, respectively. Soda lime silica glass usually contains about several weight percent of Al ₂ O ₃ component, but when there are few Al ₂ O ₃ components contained as impurities in silica sand, In addition, raw materials such as alumina, aluminum hydroxide, and feldspar can be added to adjust the composition. When cullet is used, the batch preparation ratio and the amount of colored frit added should be adjusted according to the contents of SO ₃ , vanadium oxide, manganese oxide, antimony oxide, iron oxide, cobalt oxide, etc. in the cullet. Can do. Moreover, when cobalt oxide contains in a batch, the addition amount of the coloring frit containing cobalt can be adjusted.

  In the above method, the coloring frit may be a combination of a coloring frit containing vanadium oxide, manganese oxide and antimony oxide and a frit containing no cobalt and containing cobalt oxide. Only one type of frit containing all of vanadium, manganese oxide, antimony oxide, and cobalt oxide may be used. As the colored frit added to the molten glass in the feeder, those made of low melting point glass such as borosilicate containing each colored component can be used.

The colored frit added to the molten glass to which no colored frit is added in the feeder has a vanadium oxide concentration of 1.5 to 5% by weight in terms of V ₂ O ₅ regardless of whether or not it contains cobalt oxide. The manganese oxide concentration is 3 to 11% by weight (for example, 6 to 11% by weight) in terms of MnO, and the antimony oxide concentration is 0.25 to 6% by weight (for example, 0.25 to 5% by weight in terms of Sb ₂ O ₃ ). %), And the total concentration of these three components (or the total concentration of the four components added when cobalt oxide is further added) is 6 to 15% by weight (for example, 11 to 11%). 15% by weight). If it is a colored frit having a total concentration of less than 6% by weight, the amount added to the molten glass must be excessively increased, and the temperature of the molten glass tends to decrease and the bubble breakage tends to deteriorate. If the total concentration is 6% by weight or more, such a tendency can be prevented, and if it is 11% by weight or more, it can be particularly surely prevented. Conversely, colored frit having a total concentration exceeding 15% by weight is difficult to manufacture itself, and the amount added to the molten glass must be reduced accordingly, so that the dispersion of the colored frit in the molten glass is uniform. It is hard to become.

Coloring when trying to obtain the ultraviolet-absorbing colorless transparent soda-lime-silica glass of the present invention by adding a colored frit containing vanadium oxide, manganese oxide, and antimony oxide to 100 parts by weight of molten glass to which no colored frit has been added. The addition range of frit can be easily obtained as follows. That is, for the target glass, the range of the set vanadium oxide content is V _{min to} V _max (wt%), that of manganese oxide is Mn _{min to} Mn _max (wt%), and that of antimony oxide is Sb _min to sb _max and (wt%), the measured vanadium oxide concentration of a% by weight on the colored frit used, manganese oxide concentration b wt%, when antimony oxide concentration is c wt%, the addition amount of the coloring frit W ( Parts by weight), in the glass after addition,
(A) For the vanadium oxide content to fall within the above range, the following formula (1)
V _min / 100 ≦ (a / 100) × W / (100 + W) ≦ V _max / 100 ・ ・ ・ ・ （1）
(B) In order for the manganese oxide content to fall within the above range, the following formula (2):
Mn _min / 100 ≦ (b / 100) × W / (100 + W) ≦ Mn _max / 100 (2)
(C) In order for the content of antimony oxide to fall within the above range, the following formula (3)
Sb _min / 100 ≦ (c / 100) × W / (100 + W) ≦ Sb _max / 100 (3)
Each needs to be satisfied.

When the equations (1) to (3) are modified, the following equations (1 ′) to (3 ′) are obtained, respectively.
100 / {(a / V _min ) -1} ≦ W ≦ 100 / {(a / V _max ) -1} (1 ′)
100 / {(b / Mn _min ) -1} ≦ W ≦ 100 / {(b / Mn _max ) -1} (2 ′)
100 / {(c / Sb _min ) -1} ≦ W ≦ 100 / {(c / Sb _max ) -1} (3 ′)

  Therefore, if the values of a, b, and c in the coloring frit to be used are measured and substituted into the equations (1 ′) to (3 ′), the range of W can be obtained for each equation. , The range of the added amount W of the colored frit is obtained.

  In addition, when adding cobalt oxide to molten glass using a separate colored frit containing no cobalt oxide, manganese oxide and antimony oxide and containing cobalt oxide in the feeder, the concentration of cobalt oxide in the colored frit Is preferably 0.1 to 1% by weight in terms of CoO, and the amount of the colored frit added to 100 parts by weight of the molten glass not containing the colored frit is preferably 0.4 parts by weight or less, more preferably 0 .35 parts by weight or less.

  Further, in the feeder, when cobalt oxide is added to molten glass using a colored frit containing cobalt oxide together with vanadium oxide, manganese oxide, and antimony oxide, the concentration of cobalt oxide in the colored frit is, for example, in terms of CoO. In the case of 0.025% by weight, the amount of the colored frit added to 100 parts by weight of the molten glass to which no colored frit is added is preferably 1.6 parts by weight or less, more preferably, as long as only the amount of cobalt oxide is considered. 1.4 parts by weight or less. For example, when the cobalt oxide concentration in the colored frit is 0.02% by weight in terms of CoO, the amount of the colored frit added to 100 parts by weight of the molten glass not added with the colored frit is only the amount of cobalt oxide. As a result, it is preferably 2.0 parts by weight or less, more preferably 1.75 parts by weight or less.

  EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not intended to be limited by these examples. In the examples and comparative examples, the brightness (Y), the dominant wavelength (λd), and the stimulus purity (Pe) were spectrophotometers obtained from a mirror-polished sample having a thickness of 9 to 11 mm [Hitachi Ltd., U-3010]. Was calculated based on the CIE method described in JIS Z 8701-1995 from the transmittance curve obtained by the measurement and converted to a value at 10 mm. The refractive index n was 1.5. The transmittance in the visible range of 330 nm and 430 to 780 nm was obtained from a transmittance curve obtained by measuring a sample mirror-polished to 3.5 mm thickness with the same spectrophotometer. The analysis of the glass composition was performed using a fluorescent X-ray analyzer [Rigaku Corporation, RIX3100].

[Example 1] Glass melting experiment As a sample, soda-lime-silica glass having the following standard composition was melted by raising the temperature from room temperature to 1450 ° C in an electric furnace, and held for 30 minutes after reaching 1450 ° C. Thereafter, the temperature was lowered to 1280 ° C. and held for 20 minutes. With respect to 100 parts by weight of this molten glass, 3.001% by weight (V ₂ O ₅ equivalent) vanadium oxide, 9.002% by weight (MnO equivalent) manganese oxide, 0.6% by weight (Sb ₂ O ₃ equivalent) 1.333 parts by weight of a colored frit containing the above antimony oxide was charged into the molten glass from the top of the electric furnace and held for 15 minutes. Then, it stirred uniformly for 30 minutes with the glass stirrer in a furnace, and after completion | finish of stirring, after hold | maintaining at 1280 degreeC for 30 minutes, it took out from the furnace, and was shape | molded and annealed. The electric furnace was filled with nitrogen gas, constantly measured with a combustion exhaust gas analyzer [Hodaka Co., Ltd., HT-1600N], and the oxygen concentration was kept at 2%. A measurement sample was cut out from the obtained glass and polished, and a transmittance curve was obtained with a spectrophotometer. This glass had a brightness (Y) of 87.1%, a dominant wavelength (λd) of 565.3 nm, and a stimulation purity (Pe) of 1.87% in terms of a sample thickness of 10 mm. At 330 nm, the transmittance was 6.0%. In the visible range of 430 to 780 nm, the transmittance was 88% or more, and no absorption in a specific wavelength range was observed.

<Standard composition>
SiO ₂ 73 wt%
Al ₂ O ₃ 1.9% by weight
CaO 11.1 wt%
MgO 0.16 wt%
Na ₂ O 12.5% by weight
K ₂ O 1.2 wt%
SO ₃ 0.25% by weight
Fe ₂ O ₃ 0.035 wt%

[Comparative Example 1a] Glass Production under Oxidizing Atmosphere Conditions The melting atmosphere in the electric furnace was set to the oxidizing atmosphere conditions (oxygen concentration 20.9%), and the colored frit containing the components shown in the corresponding column of Table 2 was used. Except for the above, experiments were performed under the same conditions as in Example 1, and physical properties were measured.

[Comparative Example 1b] Glass production under reducing atmosphere condition The melting atmosphere in the electric furnace was the reducing atmosphere condition (oxygen concentration 2.0%), and the colored frit containing the components shown in the corresponding column of Table 2 was used. Except for the above, experiments were performed under the same conditions as in Example 1, and physical properties were measured.

[Examples 2 to 13, Comparative Examples 2 to 3]
The physical properties were measured under the same conditions as in Example 1 except that the type of the colored frit was changed as shown in the corresponding column of Tables 1 and 2 below.

[Comparative Example 4]
The physical properties of the soda lime silica glass having the above standard composition were measured.

〔result〕
The compositions and results of the colored oxide are summarized in Tables 1 and 2 below.

(1) Results of Comparative Examples 1a and 1b The glass of Comparative Example 1b manufactured by melting under a reducing atmosphere condition has a dominant wavelength (λd) of 6 on the short wavelength side compared to the glass of Comparative Example 1a obtained by performing this under oxidizing conditions. Shifted by 6 nm. This is because Mn ³⁺ ions in manganese oxide decreased in a reducing atmosphere, and the decoloring effect decreased. This is because the decoloration effect of manganese oxide is reduced in a reducing atmosphere such as in a feeder. Therefore, if the melting experiment was not performed in a reducing atmosphere (oxygen concentration 2%) close to the actual production conditions, It shows that the obtained data is not reliable.

Results of Comparative Examples 2 and 3 In the glass of Comparative Example 3 in which frit produced by adding sodium nitrate as an oxidizer is added to the glass of Comparative Example 2, the dominant wavelength (λd) is shifted by 1.5 nm to the long wavelength side. did. This means that the oxidizing power of sodium nitrate increases Mn ³⁺ ions in the glass and the decoloring effect increases, and it is considered that sodium nitrate contributes to the coloring of manganese oxide.

(2) Results of Examples 1 to 4 Antimony oxide is added as an oxidizing agent to the glasses of Examples 1 to 4. As summarized in FIG. 1, the glasses of Examples 1 to 4 are all the main wavelengths compared to the glasses of Comparative Example 1b, Comparative Example 2 and Comparative Example 3 despite being manufactured under reducing conditions. As (λd) shifts to the longer wavelength side and the content of antimony oxide increases, the shift to the longer wavelength side increases, and the decoloring effect of manganese oxide increases. Also, the transmittance at 330 nm is low, and the ultraviolet absorption effect is also increasing.

(3) Results of Example 5 In the glass of Example 5, 0.025% of cobalt oxide was contained in the colored frit used for production, and the other colored frit compositions were the same as in Example 4. . Cobalt oxide in the glass of Example 5 is 0.00033% in terms of CoO. Compared to Example 4, the glass of Example 5 has a lightness (Y) of 2.2% lower, a dominant wavelength (λd) of 25.3 nm lower, and a stimulation purity (Pe) of 1.36% lower. Yes. The item that should be noted here is that the purity of stimulation is greatly reduced. The effect of greatly reducing the purity of the stimuli has increased the transparency of the glass and has increased the clearness. Although the dominant wavelength is greatly reduced, there is no blueness.

  In Examples 6 to 28 shown below, experiments were performed under the same conditions as in Example 1 except that the types of colored frit were changed as shown in the corresponding places in Tables 3 to 8, and physical properties were measured. Of these, in Examples 14 and 23 to 25, two types of colored frit were used in combination. The method and result in each Example are shown below.

Example 6
The antimony oxide (in terms of Sb ₂ O ₃ ) in the glass composition (% by weight) was increased to 0.06% by weight with respect to 0.039% by weight in Example 4, but the color tone value and transmittance were the same results. became. The color of the glass is colorless and transparent. Compared to Comparative Example 2 in which the glass compositions (% by weight) of vanadium oxide (V ₂ O ₅ equivalent) and manganese oxide (MnO equivalent) are the same, the dominant wavelength (λd) is shifted to the 5.5 nm long wavelength side, The decoloring effect of manganese oxide is increasing, and the colorless and transparent feeling is also increasing.

[Examples 7 and 8]
In contrast to Example 6, Example 7 and Example 8 lowered the manganese oxide content in the glass composition (% by weight). As a result, the transmittance (Y) increased, the stimulation purity (Pe) decreased, and the colorless and transparent feeling of the glass further increased. The colorless and transparent feeling of the glass is further increased in Example 8, which has a lower manganese oxide content than in Example 7. In addition, the ultraviolet absorption effect at 330 nm is equivalent to that in Example 6.

Example 9
Compared with Example 8, manganese oxide (MnO conversion) in the glass composition (wt%) was reduced to 0.065 wt% and antimony oxide (Sb ₂ O ₃ conversion) was reduced to 0.040 wt%. As a result, the dominant wavelength (λd) was shifted to the 2.5 nm shorter wavelength side than Example 8, but the colorless and transparent feeling of the glass was the same. Compared with Comparative Example 1b in which the green coloration of vanadium oxide remains, in Example 9, the dominant wavelength (λd) shifted to the 4.3 nm long wavelength side, and the glass became colorless and transparent. As a result, it can be seen that the use of antimony oxide in combination is more advantageous in increasing the decoloring effect than the use of only sodium nitrate as an oxidizing agent.

[Examples 10 to 13]
The vanadium oxide (V ₂ O ₅ equivalent) 0.03% by weight and manganese oxide (MnO equivalent) 0.100% by weight in the glass composition (% by weight) were the same, and the antimony oxide weight% was changed. As the content of antimony oxide was increased, λd was shifted to the longer wavelength side, and the ultraviolet transmittance at 330 nm was decreasing. All the glasses of Examples 10 to 13 are colorless and transparent.

Example 14
In the glass of Example 14, the colored frit containing cobalt oxide and the colored frit used in Example 13 were mixed. Cobalt oxide in the glass composition (% by weight) is 0.00025% by weight in terms of CoO. Compared to Example 13, the glass of Example 14 has a lightness (Y) of 2.0% lower, a dominant wavelength (λd) of 15.4 nm lower, and a stimulus purity (Pe) of 1.13% lower. Yes. Similar to the glass of Example 5, the effect of greatly reducing the stimulus purity increases the transparency of the glass and increases the clearness. Although the dominant wavelength is greatly reduced, there is no blueness.

Example 15
For the glass of Example 13, only the manganese oxide (MnO equivalent) in the glass composition (% by weight) was reduced to 0.08% by weight. Compared to Example 13, the glass of Example 15 has a brightness (Y) of 0.8% higher, a dominant wavelength (λd) of 3.5 nm lower, and a stimulus purity (Pe) of 0.2% lower. Yes. Since the brightness (Y) increased and the stimulation purity (Pe) decreased, the transparency of the glass of Example 13 increased. Although the dominant wavelength (λd) is low, the decoloring effect of manganese oxide is sufficient, and the glass is also colorless and transparent.

Example 16
For the glass of Example 15, only manganese oxide (MnO equivalent) in the glass composition (% by weight) was reduced to 0.065% by weight. Compared to Example 15, the glass of Example 16 has a brightness (Y) of 0.2% higher, a dominant wavelength (λd) of 0.4 nm higher, and a stimulus purity (Pe) of 0.08% lower. Yes. Since the brightness (Y) increased and the stimulation purity (Pe) decreased, the transparency of the glass of Example 15 increased. The dominant wavelength (λd) is also the same, the decoloring effect of manganese oxide is sufficient, and the glass is also colorless and transparent.

Example 17
For the glass of Example 16, only manganese oxide (MnO equivalent) in the glass composition (% by weight) was reduced to 0.055% by weight. Compared to Example 16, the glass of Example 17 has a brightness (Y) of 0.2% higher, a dominant wavelength (λd) of 3.0 nm lower, and a stimulus purity (Pe) of 0.05% lower. Yes. Since the brightness (Y) increased and the stimulation purity (Pe) decreased, the transparency of the glass of Example 16 increased. Although the dominant wavelength (λd) is low, the decoloring effect of manganese oxide is still sufficient, and the glass is also colorless and transparent. Antimony oxide and sodium nitrate, an oxidizing agent, can maintain the transparency and decoloring effect of glass even when manganese oxide (MnO equivalent) in the glass composition (% by weight) is reduced to 0.055% by weight. It is thought that it may be due to some synergistic effect by the combination.

Example 18
For the glass of Example 17, only antimony oxide (in terms of Sb ₂ O ₃ ) in the glass composition (wt%) was reduced to 0.040 wt%. Compared to Example 17, the glass of Example 18 has a brightness (Y) of 0.1% higher, a dominant wavelength (λd) of 1.0 nm lower, and a stimulus purity (Pe) of 0.01% lower. Yes. The brightness (Y) and the stimulation purity (Pe) are the same as in Example 17, and the transparency is also the same. Although the dominant wavelength (λd) is low, the decoloring effect of manganese oxide is still sufficient, the glass is also colorless and transparent, and the ultraviolet light transmittance effect is also sufficient.

[Examples 19 and 20]
In Examples 19 and 20, vanadium oxide (V ₂ O ₅ conversion) in the glass composition (% by weight) is 0.02%, and manganese oxide (MnO conversion) is 0.03% by weight. Only antimony oxide in the glass composition (wt%) was changed. The antimony oxide (converted to Sb ₂ O ₃ ) of 0.04% by weight of Example 20 was 1.3 nm higher at λd, and the decolorization effect of manganese oxide was higher. Even at the ultraviolet transmittance of 330 nm, the absorption effect of Example 20 is increased by 2.6%. In both Examples 19 and 20, the color tone is colorless and transparent, and the ultraviolet transmittance is 20% or less. Manganese oxide still has sufficient decoloring effect, and the glass is also colorless and transparent. Even if the manganese oxide (MnO equivalent) is reduced to 0.03% by weight, the transparency and decoloring effect of the glass can be maintained due to some synergistic effect due to the combination of antimony oxide and sodium nitrate, an oxidizing agent. It may be a thing.

[Example 21]
Vanadium oxide (V ₂ O ₅ conversion) in the glass composition (wt%) was 0.025 wt%, and the V ₂ O ₅ / MnO ratio was 0.73. The glass was colorless and transparent, and the ultraviolet transmittance at 330 nm was 14.2%. Even if the manganese oxide (MnO conversion) in the glass composition (% by weight) was lowered to 0.035%, the decoloring effect was maintained.

[Example 22]
Compared to Example 21, manganese oxide and antimony oxide in the glass composition (% by weight) were increased. The glass was colorless and transparent, and the ultraviolet transmittance at 330 nm was 12.5%. Compared with Example 21, the ultraviolet transmittance at 330 nm decreased by 1.7%. The decrease in UV transmittance is due to the effect of increasing antimony oxide.

[Examples 23 and 24]
The glass of Example 23 and Example 24 is a glass obtained by mixing a frit containing vanadium oxide, manganese oxide and antimony oxide and a frit containing cobalt oxide. Glass of Example 23, antimony oxide in the glass composition (wt%) _(Sb 2 _{O 3} equivalent) of 0.005%, the glass of Example 24 is 0.06%. In other respects, both glass compositions are the same. The color tone values of the glass of Example 23 and the glass of Example 24 are substantially the same. This seems to be largely influenced by cobalt oxide (0.0003 wt%) in the glass composition (wt%). The UV transmittance at 330 nm is about 2%, which is almost the same. However, the glass of Example 23 and the glass of Example 24 are colorless and transparent and have a clear feeling of glass. The ultraviolet transmittance at 330 nm is very low at 2% or less in both Example 23 and Example 24.

Example 25
For the glass of Example 24, only the manganese oxide (MnO equivalent) in the glass composition (% by weight) was increased to 0.16% by weight. Compared to Example 24, the glass of Example 25 has a lightness (Y) of 1.5% lower, a dominant wavelength (λd) of 8.5 nm higher, and a stimulus purity (Pe) of 0.37% higher. However, it is colorless and transparent. The ultraviolet transmittance at 330 nm is very low at 1.8%.

Example 26
The vanadium oxide (V ₂ O ₅ conversion) in the glass composition (wt%) was 0.06 wt%, the manganese oxide (MnO conversion) was 0.085 wt%, and the V ₂ O ₅ / MnO ratio was 0.71. Antimony oxide (Sb ₂ O ₃ conversion) was 0.04% by weight. It is colorless and transparent, and its ultraviolet transmittance at 330 nm is as low as 1.9%.

Example 27
For the glass of Example 26, only the manganese oxide (MnO equivalent) in the glass composition (% by weight) was reduced to 0.075% by weight, and the V ₂ O ₅ / MnO ratio was 0.80. Compared to Example 26, the glass of Example 27 has a brightness (Y) of 0.3% higher, a dominant wavelength (λd) of 0.9 nm lower, and a stimulus purity (Pe) of 0.11% lower. Yes. The glass of Example 27 became a colorless transparent glass having a clearer feeling than that of the glass of Example 26. The ultraviolet transmittance at 330 nm is very low at 1.9%.

Example 28
For the glass of Example 27, only antimony oxide (in terms of Sb ₂ O ₃ ) in the glass composition (% by weight) was reduced to 0.020% by weight. Compared to the glass of Example 27, the glass of Example 28 has a brightness (Y) of 0.3% higher, a dominant wavelength (λd) of 2.4 nm lower, and a stimulus purity (Pe) of 0.13% lower. Thus, a clear and colorless glass having a clearer feeling than that of the glass of Example 27 was obtained.

The conditions and results of Examples 6 to 28 are summarized in Tables 3 to 8 below.

According to the present invention, in order to obtain an ultraviolet-absorbing colorless and transparent soda-lime-silica glass that can achieve a highly efficient and stable decoloring effect and maintain a high light transmittance in the visible range in a glass manufacturing process on an industrial scale. Can be used. The glass of the present invention is useful in that it can show the contents clearly when it is in the form of a container, and at the same time, it can prevent coloring, discoloration, discoloration, flavor deterioration, etc. of the contents due to ultraviolet rays. high. In addition, the glass of the present invention has an advantage that it can be reused as a cullet of ordinary colorless and transparent glass.

Claims (8)

It contains vanadium oxide, manganese oxide, and antimony oxide, the vanadium oxide content is 0.02 to 0.06 wt% in terms of V ₂ O ₅ , and the manganese oxide content is 0.03 to 0.3 in terms of MnO. An ultraviolet-absorbing colorless and transparent soda-lime-silica glass characterized by 20% by weight and an antimony oxide content of 0.005 to 0.06% by weight in terms of Sb ₂ O ₃ . The ultraviolet-absorbing colorless and transparent soda-lime-silica glass according to claim 1, wherein the weight ratio of vanadium oxide and manganese oxide is 0.1 or more and less than 0.6 in terms of V ₂ O ₅ / MnO. The ultraviolet-absorbing colorless and transparent soda-lime-silica glass according to claim 1, wherein the weight ratio of vanadium oxide to manganese oxide is 0.6 or more and less than 0.9 in terms of V ₂ O ₅ / MnO.   The ultraviolet-absorbing colorless and transparent soda-lime silica glass according to any one of claims 1 to 3, wherein the content of cobalt oxide is 0.0004 wt% or less in terms of CoO. The ultraviolet-absorbing colorless and transparent soda-lime-silica glass according to any one of claims 1 to 4, wherein the content of SO ₃ is 0.15 to 0.30% by weight.   In the transmittance curve measured at a thickness of 3.5 mm, the transmittance at a wavelength of 330 nm is 20% or less, and there is no absorption in a specific wavelength region in the visible region of a wavelength of 430 to 780 nm, and the transmittance is 80% or more. The ultraviolet-absorbing colorless and transparent soda-lime-silica glass according to any one of claims 1 to 5.   In the transmittance curve measured at a thickness of 3.5 mm, the transmittance at a wavelength of 330 nm is 10% or less, and there is no absorption in a specific wavelength region in the visible region of a wavelength of 430 to 780 nm, and the transmittance is 80% or more. The ultraviolet-absorbing colorless and transparent soda-lime-silica glass according to any one of claims 1 to 5. A glass container formed by molding the ultraviolet-absorbing colorless and transparent soda-lime-silica glass according to claim 1.

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