JP2019094244A - Green blue soda lime-silica-based glass, manufacturing method therefor, and green blue glass container - Google Patents

Abstract

To provide a composition capable of stably and efficiently manufacturing a green blue soda lime-silica-based glass having a calm color tone with more bluish than emerald green color with depth by suppressing content of an iron component as a blue tone component as much as possible.SOLUTION: There is provided a green blue soda lime-silica-based glass containing, by mass%, 0.13 to 0.23%(in terms of FeO), SO0.07 to 0.17%, chromium oxide 0.17 to 0.23% (in terms of CrO), cobalt oxide 0.0023 to 0.010% (in terms of CoO) in a composition, and having cobalt oxide (in terms of CoO)/chromium oxide (in terms of CrO) of 0.013 to 0.045.SELECTED DRAWING: None

Description

  The present invention relates to a soda lime silica glass having a greenish-blue color tone that is bluish than EG (emerald green) color, a method for producing the same, and a glass container having a green-blue color tone. More specifically, the present invention is a green-blue soda lime silica glass having a deep and calm color, which can be found in overseas-made beer bottles, etc. Manufacturing method in a range that does not cause excessive influence of

  Soda-lime-silica glass, which has a greenish-blue color tone, uses the green and copper (II) ions exhibited by the chromium ions in the glass in Europe and the United States of America, and the light blue to pale blue color exhibited by the iron (II) ions. It is manufactured. However, if the glass contains a large amount of copper ions and iron ions, the color tone is likely to change due to the glass redox (redox state) and the atmosphere (oxygen concentration etc.) of the melting furnace. It is also difficult to produce soda-lime-silica-based glass having a greenish-blue color tone because of the possibility of precipitation of copper).

  In particular, when a change in color tone or occurrence of a stone is observed in one lot in a manufactured glass container, the glass container of the lot is a nonconforming item that can not be delivered to the user. For this reason, it is extremely important that the state of the glass during melting be stable.

  In addition, even if it is possible to control the redox of the glass and the atmosphere of the melting furnace and to stabilize the color tone, it is possible to produce a glass rich in iron as it is a glass of various color tone other than colorless (flint) and brown (amber) In a melting furnace called a color kiln, it takes a long time to adjust the color tone and color composition during color change, which may adversely affect the productivity of subsequently produced glass of different color tone.

  In the glass manufacturing line, the melting furnace is operated continuously for 24 hours. For this reason, in the transition step (color change of glass) when producing glass containers of different colors following a glass container of a certain color, the raw material of the subsequent glass follows the preceding melt present in the furnace. While being fed, the melt in the furnace is gradually replaced by the melt of the subsequent glass while being fed. Therefore, when the preceding glass is likely to affect the physical properties such as the color tone of the subsequent glass at the time of color change, it takes a long time for sufficient color change, and in the meanwhile, it results in mass production of glass that can not be made into products Manufacturing costs are significantly increased.

  Furthermore, there is also a problem that since the amount of iron (II) ions increases as the amount of iron in the whole increases and the glass melt absorbs infrared rays, much energy is required to raise the temperature of the furnace bottom.

  The method of manufacturing dark green glass is disclosed by Unexamined-Japanese-Patent No. 2001-58847 (patent document 1). However, since this glass contains a large amount of hexavalent chromium that absorbs light on the short wavelength side, it tends to have a yellowish color, and the proportion of embedded cullet is extremely high at 80 to 95%. “Incl cullet” refers to cullet of colors other than colorless (flint) and brown (amber) recovered from the market, in principle, for example, emerald green (EG), blue, dead leaf color, black, french green, It contains mixed cullet such as smoke color. For this reason, the composition and the redox change, and it is difficult to increase the amount of embedded cullet used. Although the glass disclosed in Patent Document 1 has such a high proportion of embedded cullet as described above, the proportion of potassium dichromate in the raw batch also increases accordingly, and a chromium stone is generated, It has been difficult to stably and efficiently produce a deep blue, soda-lime-silica-based glass with a calm color tone.

JP 2001-058847 A

  Under the above background, the present invention is a greenish blue soda lime silica glass having a deep and calm color, which is bluish than EG (emerald green) color, and has an iron content as a bluish component as much as possible. An object of the present invention is to obtain a composition which can be stably, efficiently and efficiently manufactured.

  Another object of the present invention is to make it possible to use a large amount of embedded cullet, which exists in the market, in a range that does not excessively affect the color tone and the productivity of glass.

In view of the above problems, the present inventors pay attention to cobalt which is not easily affected by the color change due to the redox of the glass or the change of the melting furnace atmosphere, and it is contained as a component to make bluish color, iron, chromium, By controlling the content of SO ₃ and specifying the ratio of cobalt to chromium, it is found that green-blue soda lime silica glass can be obtained stably even if the inclusion cullet is used a lot, and the present invention is completed. I did.

That is, according to the present invention, iron oxide 0.13 to 0.23% (Fe ₂ O ₃ equivalent), SO ₃ 0.07 to 0.17%, chromium oxide 0.17 to 0 in mass% in composition. .23% (Cr ₂ O ₃ equivalent), containing 0.0023 to 0.010% cobalt oxide (CoO equivalent), and cobalt oxide (CoO equivalent) / chromium oxide (Cr ₂ O ₃ equivalent) 0.013 to 10 The present invention provides a green-blue soda lime silica glass characterized by being 0.045.

In addition, the green-blue soda lime silica glass of the present invention is represented by mass% in the composition, iron oxide 0.15 to 0.22% (Fe ₂ O ₃ equivalent), SO ₃ 0.08 to 0.13 %, Chromium oxide 0.18 to 0.22% (Cr ₂ O ₃ equivalent), cobalt oxide 0.003 to 0.007% (CoO equivalent), and cobalt oxide (CoO equivalent) / chromium oxide (Cr ₂₎ it is preferable O ₃ basis) is from 0.015 to 0.040.

Note that the iron oxide referred to any of the Fe ₂ O ₃ and FeO, but its mass percentages are those obtained by converting all of the iron oxide contained in the glass as Fe ₂ O _3. Similarly, although chromium oxide and cobalt oxide having different valences in glass may exist, they are represented as Cr ₂ O ₃ and CoO, respectively.

In addition, the green-blue soda lime silica glass of the present invention is typically represented by mass%, SiO ₂ 65-75%, Al ₂ O ₃ 0.5-5%, CaO 6-15%, MgO 0 to 4%, Na ₂ O 10 to 17%, K ₂ O 0 to 4%, iron oxide 0.13 to 0.23% (Fe ₂ O ₃ conversion), SO ₃ 0.07 to 0.17%, Containing chromium oxide 0.17 to 0.23% (Cr ₂ O ₃ equivalent), cobalt oxide 0.0023 to 0.010% (CoO equivalent), and cobalt oxide (CoO equivalent) / chromium oxide (Cr ₂ O ₃₎ Preferably, it is 0.013 to 0.045.

In addition, the green-blue soda lime silica glass of the present invention is represented by mass% as SiO ₂ 68-74%, Al ₂ O ₃ 1-4%, CaO 8-13%, MgO 0.1-3%, 11 to 15% of Na ₂ O, 0.1 to 3% of K ₂ O, 0.15 to 0.22% of iron oxide (Fe ₂ O ₃ equivalent), 0.08 to 0.13% of SO ₃ , chromium oxide 0 .18 to 0.22% (Cr ₂ O ₃ equivalent), cobalt oxide 0.003 to 0.007% (CoO equivalent) included, and cobalt oxide (CoO equivalent) / chromium oxide (Cr ₂ O ₃ equivalent) More preferably, it is 0.015 to 0.040.

  The color tone of the greenish blue soda lime silica glass of the present invention is CIE indication (thickness 2 mm conversion), lightness (Y) = 60 to 71%, main wavelength (λ d) = 546 to 556 nm, stimulation purity (Pe) = It is preferably 10 to 21%.

  In addition, the color tone of the greenish blue soda lime silica glass of the present invention is CIE indication (thickness 2 mm conversion), lightness (Y) = 62 to 70%, main wavelength (λ d) = 548 to 555 nm, stimulation purity (Pe It is more preferable that it is = 12 to 18%.

  Here, the color tone parameter is based on the CIE method described in JIS Z8781-3: 2016 (old JIS Z8701-1999).

  A greenish blue glass container can be obtained by molding the greenish blue soda lime silica glass of the present invention having the above composition and characteristics.

  The term "glass container" as used herein includes glass bottles, glass dishes, glass vases and the like.

In the method for producing green-blue soda lime silica glass of the present invention, when the total amount after vitrification is 100 parts by mass, the amount of embedded cullet used is 50 to 80 parts by mass and the total cullet (the source and type are different) Prepare the cullet in such a way that the total amount of cullet used is 70 to 95 parts by mass, and 0.10 to 0.25 parts by mass of potassium dichromate and 0.0011 to 0.010 parts by mass to the prepared cullet It is characterized by adding a raw batch composition containing cobalt oxide (Co ₃ O ₄ ). Here, "raw batch" refers to other than cullet in the glass material composition.

In the method of the present invention for producing green-blue soda lime silica glass, the amount of embedded cullet used is 55 to 75 parts by mass, and the total amount of cullet used is 80, based on 100 parts by mass of the total amount after vitrification. Add a batch composition containing 0.11 to 0.24 parts by weight of potassium dichromate and 0.0020 to 0.0075 parts by weight of cobalt oxide (Co ₃ O ₄ ) to cullet which is ̃93 parts by weight It is preferable to do.

  With the above-mentioned configuration, the greenish-blue soda lime silica glass having a deep and calm color, which is bluish than EG (emerald green) color, is a reducing cullet which has conventionally been used at a low rate. , It can be manufactured by using it in a range where the influence on the color tone and productivity of glass is not excessive.

SiO ₂ is a glass-forming oxide, and it is generally preferable to contain it in a proportion of 65 to 75% by mass. This is because if the content of SiO ₂ is less than 65% by mass, the chemical durability of the glass may be lowered, and if it exceeds 75% by mass, it tends to be easily devitrified. In consideration of the chemical durability and the devitrification of the glass, SiO ₂ is more preferably contained in a proportion of 68 to 74% by mass.

Al ₂ O ₃ is a glass intermediate oxide and has the effect of improving the chemical durability of the glass. It is generally preferred to contain Al ₂ O ₃ in a proportion of 0.5 to 5% by mass. This is because if the content of Al ₂ O ₃ is less than 0.5% by mass, chemical durability may be insufficient, and if it exceeds 5% by mass, melting of the glass may be difficult. It is. In consideration of the chemical durability, the meltability and the like of the glass, Al ₂ O ₃ is more preferably contained in a ratio of 1 to 4% by mass. When the amount of alumina component contained in the raw material silica sand is small, the content of Al ₂ O ₃ can be adjusted by adding raw materials such as alumina, aluminum hydroxide, feldspar and the like.

  CaO is a glass-modified oxide, and has the effect of improving the chemical durability of the glass, as well as improving the meltability. It is generally preferred that CaO be contained in a proportion of 6 to 15% by mass. This is because if the content of CaO is less than 6% by mass, chemical durability may be insufficient, and if it exceeds 15% by mass, devitrification tends to occur. In consideration of the chemical durability, meltability, devitrification and the like of the glass, CaO is more preferably contained at a ratio of 8 to 13% by mass.

  MgO is a glass-modified oxide and, like CaO, has the effect of improving the chemical durability of the glass and also improves the meltability. Although the content of MgO is not essential, when it is contained, it is generally preferable to use a ratio of 4% by mass or less. This is because if the content of MgO exceeds 4% by mass, devitrification tends to occur. In consideration of the chemical durability, meltability, devitrification and the like of the glass, MgO is more preferably contained in a ratio of 0.1 to 3% by mass.

Na ₂ O is a glass-modified oxide and has the effect of promoting the melting of the raw material, and it is generally preferred to be contained in a proportion of 10 to 17% by mass. This is because if the content of Na ₂ O is less than 10% by mass, melting of the glass becomes difficult, and conversely, if it exceeds 17% by mass, the chemical durability of the glass may be reduced. In consideration of the meltability, chemical durability and the like of the glass, Na ₂ O is more preferably contained in a proportion of 11 to 15% by mass.

K ₂ O is a glass-modified oxide and, like Na ₂ O, has the effect of promoting the melting of the raw material. Although the content of K ₂ O is not essential, when it is contained, it is generally preferable to use a ratio of 4% by mass or less. This is because devitrification tends to occur when the content of K ₂ O exceeds 4% by mass. In consideration of the meltability, devitrification and the like of the glass, K ₂ O is more preferably contained at a ratio of 0.1 to 3% by mass.

Iron oxide is a total of iron added in the form of iron contained in silica sand of glass material batch as impurities or in the form of Fe ₂ O ₃ , the content in glass is 0.23 mass% or less in terms of Fe ₂ O ₃ It is essential that If it exceeds 0.23% by mass, the amount of divalent iron ions will increase, making it difficult to control bluishness, and the energy efficiency of the melting furnace may deteriorate. Further, if the content in the glass is less than 0.13% by mass in terms of Fe ₂ O ₃ , the absorption of infrared rays decreases, so the furnace bottom temperature rises and temperature control becomes difficult. In addition, when soda lime silica glass added with iron oxide, mirabilite, and carbon is melted in an atmosphere with low oxygen concentration, it tends to exhibit an amber color, which also causes defects such as color streaks. Furthermore, there is a possibility that the productivity of the glass of different color tone to be manufactured next may be adversely affected, for example, it takes a long time for color tone adjustment and composition adjustment at the time of color change. The content of iron oxide is preferably 0.15 to 0.22% by mass in terms of Fe ₂ O ₃ in consideration of protection of the contents from ultraviolet light when used as a container, control of color tone, productivity, etc. .

SO ₃ is the residue in the glass and the residue derived from cullet of the fining agent added to the raw material batch by the combination of sodium sulfate and carbon, and it is essential to make the amount 0.07 to 0.17% by mass It is. Within this range, the amounts of oxidizing agent, reducing agent and cullet that govern the redox of mirabilite, carbon and other raw material batches can be determined. The lower limit of 0.07% by mass is that if the SO ₃ content in the glass is less than this, the glass is biased to the reducing side, the ratio of FeO to Fe ₂ O ₃ becomes high, and the amount of CoO depends on It is because there is a possibility that it becomes difficult to control the bluish taste and the energy efficiency of the melting furnace may deteriorate. If the content of SO ₃ exceeds 0.17% by mass, the glass is biased to the oxidizing side, and there is a possibility that yellow color may be exhibited due to absorption centered on 375 nm by the CrO ₄ ^2- group. In consideration of ease of color tone control, energy efficiency of the melting furnace, influence on the quality of the glass substrate, etc., the content of SO ₃ is preferably 0.08 to 0.13% by mass.

Chromium oxide is a component that causes the glass to be colored green, and it is essential that 0.17 to 0.23% by mass in terms of Cr ₂ O ₃ be contained in the glass. When the content of chromium oxide is less than 0.17% by mass in terms of Cr ₂ O ₃ , the color tone becomes too light and it becomes difficult to exhibit a vivid green-blue color tone, and when it is used as a glass container There is a possibility that the protection effect against light of objects may deteriorate. In addition, if the content of chromium oxide exceeds 0.23 mass%, the color tone becomes too deep, and when it is used as a glass container, there is a possibility that foreign substance inspection (actual bottle inspection) after filling the contents becomes difficult. It also leads to the generation of The content of chromium oxide is preferably 0.18 to 0.22% by mass in terms of Cr ₂ O ₃ from the viewpoints of vivid color tone, protection of contents, foreign matter inspection, prevention of chromium stone formation, and the like.

  Cobalt oxide is a component that imparts bluish taste to glass, and is characterized by being less susceptible to oxidation reduction and heat treatment, and not to change the color tone of the glass. It is essential that cobalt oxide is contained in the glass in an amount of 0.0023 to 0.010% by mass in terms of CoO. When the content of cobalt oxide is less than 0.0023% by mass in terms of CoO, it becomes difficult to obtain a greenish blue glass having a deep and calm color tone, and it becomes difficult to recognize a difference from EG color glass There is a fear. On the other hand, if it exceeds 0.010% by mass, bluishness may be too strong. The content of cobalt oxide is preferably 0.003 to 0.007% by mass in terms of CoO in order to obtain a greenish blue glass having a desired deep and stable color tone more stably.

Moreover, it is essential that the mass ratio of cobalt oxide to chromium oxide in the glass is 0.013 to 0.045 in terms of CoO / Cr ₂ O ₃ . When the mass ratio of cobalt oxide to chromium oxide is in the above-mentioned range, it is possible to obtain a green-blue soda lime silica glass having a well-balanced, deep and calm color tone. If the mass ratio is less than 0.013, bluing may be insufficient, and if it exceeds 0.045, bluing may be excessive, and it may be difficult to obtain a greenish blue glass having a desired color tone. The mass ratio of cobalt oxide to chromium oxide in the glass is more preferably 0.015 to 0.040 in terms of CoO / Cr ₂ O ₃ .

  The color tone of the greenish blue soda lime silica glass according to the present invention is CIE indication (thick 2 mm equivalent) described in JIS Z 8781-3: 2016, lightness (Y) = 60 to 71%, dominant wavelength (λd) = It is preferable that it is 546-556 nm and stimulation purity (Pe) = 10-21%. If the lightness (Y) is less than 60%, the color becomes too deep, and if it exceeds 71%, the color may become too thin. If the dominant wavelength (λd) is less than 546 nm, bluing may be too strong, and if it exceeds 556 nm, bluing may be too weak to make it difficult to recognize a difference from EG color glass. When the stimulation purity (Pe) is less than 10%, the color becomes hazy and inferior in luxury feeling, and when it exceeds 21%, the color becomes too vivid and a difference with EG color glass is hardly recognized. In order to obtain a greenish blue soda lime silica glass with a well-balanced deep and calm color and good recyclability, lightness (Y) = 62 to 70%, dominant wavelength (λd) = 548 to 555 nm, stimulation Preferably, the purity (Pe) is 12 to 18%.

  The green-blue soda lime silica glass of the above composition is melted for about 24 hours at a glass melting temperature of about 1500 ° C. in a continuous melting furnace with a melting capacity of 100 tons / day, and further passed through a feeder of about 1270 ° C. Green-blue-based glass containers can be obtained by molding with an IS machine (automatic furnace).

According to the present invention, it is possible to obtain a desired green-blue soda lime silica glass while using a large amount of cullet conventionally used in a small amount. Generally the composition of the write _cullet, SiO 2 70 to 73 _wt%, Al ₂ O 3 _1~3 wt%, CaO 9 to 12 wt%, MgO 0.3 to 1.5 _wt%, Na 2 O _12~14 mass _%, K 2 O 0.5 to 2 wt%, iron oxide _(Fe 2 _{O 3} basis) 0.2-0.3 _wt%, SO 3 0.06 to 0.25 wt%, chromium oxide _(Cr 2 O ₃ ) 0.08 to 0.16% by mass, cobalt oxide (CoO equivalent) 0.0003 to 0.0005% by mass.

In addition, in order to increase the usage rate of the entire cullet, EG-based glass cullet (called factory cullet) generated in its own factory is also used, but iron oxide (Fe ₂ O ₃ equivalent) is about 0.17 mass%, It is almost the same as the above-mentioned embedded cullet except that the content of cobalt oxide (in terms of CoO) is about 0.002 mass% and the content of copper oxide (in terms of CuO) is about 0.007 mass%. It should be noted that factory cullet is easier to use because it has a known identity compared to the incullet collected from the market.

In the method for producing green-blue soda lime silica glass according to the present invention, when the total amount after vitrification is 100 parts by mass, the used amount of embedded cullet is 50 to 80 parts by mass, and the total amount of cullet used is 75 to 5 Raw batch containing 0.10 to 0.25 parts by weight of potassium dichromate and 0.0011 to 0.010 parts by weight of cobalt oxide (Co ₃ O ₄ ) in cullet prepared to be 95 parts by weight Add the composition. If the amount of the incorporated cullet used is less than 50 parts by mass, the incorporated cullet recovered from the market can not be used sufficiently. Conversely if it exceeds 80 parts by mass, it may be difficult to control the color tone. Further, if the total amount of cullet is less than 75 parts by mass, it is necessary to increase the addition amount of potassium dichromate and cobalt oxide, which may lead to cost increase. Conversely, if the total amount of cullet exceeds 95 parts by mass, it may be difficult to control the color tone. In order to stably produce a deep blue green-blue soda lime silica glass having a calm color, the amount of embedded cullet used is 55 to 75 parts by mass, assuming that the total amount after vitrification is 100 parts by mass, and The total cullet amount used is 80 to 93 parts by mass of cullet, containing 0.11 to 0.24 parts by mass of potassium dichromate and 0.0020 to 0.0075 parts by mass of cobalt oxide (Co ₃ O ₄ ) It is more preferred to add the raw batch composition.

  EXAMPLES Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited by these examples.

  In the examples and comparative examples, a spectrophotometer equipped with an integrating sphere (sample with both surfaces mirror-polished so that the lightness (Y), the dominant wavelength (λd), and the excitation purity (Pe) become about 2 mm thick From the transmittance curve obtained by measurement using U-3010) manufactured by Hitachi, Ltd., it is calculated based on the CIE method described in JIS Z 8781-3: 2016, and converted to a value at a thickness of 2 mm.

  The analysis of the glass composition was performed using a fluorescent X-ray analyzer (ZSX Primus II, manufactured by Rigaku Corporation) according to a calibration curve method (analytical diameter: 30 mm) prepared in advance using standard sample glass.

Comparative Example 1
A green-blue beer bottle made overseas was obtained, and a sample for measurement was cut out from the bottom and polished. The transmittance curve of this measurement sample was determined using a spectrophotometer, and the lightness (Y), dominant wavelength (λd), and excitation purity (Pe) in terms of 2 mm thickness were determined. Y = 66.8%, λd = 555.8 nm, Pe = 18.2%.

Moreover, when the glass composition was calculated | required with the fluorescent-X-ray-analysis apparatus by the calibration curve method using the disk of this glass, it was the following composition ratio (mass%). SiO ₂ : 71.6% by mass, Al ₂ O ₃ : 1.9% by mass, TiO ₂ : 0.058% by mass, CaO: 10.5% by mass, MgO: 0.57% by mass, Na ₂ O: 13 .4 mass%, K ₂ O: 0.5 mass%, iron oxide (Fe ₂ O ₃ conversion): 0.355 mass%, SO ₃ : 0.111 mass%, chromium oxide (Cr ₂ O ₃ conversion): 0.233 mass%. The results are summarized in Table 2A. Greenish blue soda lime silica glass made in foreign countries has high iron oxide content and is bluish colored by divalent iron ions, making it difficult to control color tone, low energy efficiency, and color change Difficulty is expected.

Example 1
The following raw materials were weighed and mixed to prepare a batch composition.
Kemerton silica sand: 100 parts by mass, lime: 27.5 parts by mass, soda ash: 27.6 parts by mass, Fe ₂ O ₃ : 0, mirabilite: 2.5 parts by mass, carbon (coel coke carbon having a purity of 85%): 0.05 parts by mass, potassium dichromate: 1.8 parts by mass, Co ₃ O ₄ : 0.025 parts by mass, embedded cullet: 550 parts by mass, factory cullet (excrement ECEG): 200 parts by mass. The usage rate of embedded cullet is 62.3%, and the usage rate of total cullet is 84.9%. When the total amount of glass after vitrification is 100 parts by mass, 0.20 parts by mass of potassium dichromate added in the form of a raw batch composition and 0.0028 of cobalt oxide (Co ₃ O ₄ ) are added. It is a mass part.

The obtained batch composition was charged into a 100 mL Pt-Rh crucible, placed in an electric furnace (SUPERBURN manufactured by Motoyama), melted at 1450 ° C. for 2 hours, and molded into a disc shape. The oxygen concentration in the electric furnace was about 20%. The obtained glass was processed in the same manner as in Comparative Example 1 to obtain color tone data and a glass composition. The lightness (Y), dominant wavelength (λd), and stimulation purity (Pe) in terms of 2 mm thickness were Y = 67.2%, λd = 554.9 nm, and Pe = 14.8%. In addition, the glass composition (analytical value) is SiO ₂ : 71.6% by mass, Al ₂ O ₃ : 1.9% by mass, TiO ₂ : 0.042% by mass, CaO: 10.8% by mass, MgO: 0 .70 mass%, Na ₂ O: 12.8 mass%, K ₂ O: 1.1 mass%, iron oxide (Fe ₂ O ₃ equivalent): 0.186 mass%, SO ₃ : 0.119 mass%, It was 0.202 mass% of chromium oxide (Cr ₂ O ₃ conversion), and 0.0036 mass% of cobalt oxide (CoO conversion). Cobalt oxide (CoO equivalent) / chromium oxide (Cr ₂ O ₃ equivalent) was 0.018. The results are summarized in Table 1A.

  From the color tone data, it is understood that the glass of Example 1 is a greenish blue soda lime silica glass having a deep and calm color. Further, the glass of Example 1 has iron content which is 1/2 or less of that of the same color glass made in Comparative Example 1 of Comparative Example 1, which can increase the usage rate of the embedded cullet, and control of color tone, productivity, cost It is also advantageous in point.

[Examples 2 to 7]
In the same manner as in Example 1, the glass of each example was produced using an electric furnace at the raw material mixing ratio shown in Tables 1A to 1C, and was formed into a disc shape. Subsequently, the color tone data and the glass composition were determined in the same manner as in Example 1. The results are also shown in Tables 1A-1C.

  In Tables 1A to 1C, “excrement (ECEG)” indicates a factory cullet of emerald green of the ecology bottle, and “exclusion (green-blue)” indicates a factory cullet of green-blue.

  The results shown in Tables 1A to 1C indicate that the greenish blue soda lime silica glass of Examples 2 to 7 exhibits a deep and calm color tone.

[Examples 8 to 14]
In the glass bottle manufacturing line, a batch consisting of inset cullet, factory cullet, and raw batch is prepared at the blending ratio of raw materials shown in Tables 1C to 1E, introduced into a continuous melting furnace with a melting capacity of 100 t / day, and glass melting temperature approx. The mixture was melted at 1500 ° C. for about 24 hours, passed through a feeder at about 1270 ° C., molded and gradually cooled to produce a glass bottle with an inner volume of 330 mL. The concentration of SO ₃ changes with the oxygen concentration in the glass melting furnace, which affects the color tone of the glass. The oxygen concentration in the glass melting furnace in actual production was less than 5%. A sample for measurement was prepared in the same manner as Comparative Example 1, and the glass composition and color tone data were determined. The results are also shown in Tables 1C-1E. The results show that the greenish blue soda lime silica glass of Examples 8 to 14 exhibits a deep and calm color tone.

Comparative Examples 2 to 4
The glass of each comparative example was manufactured using the electric furnace with the raw material mixture ratio shown to Tables 2A-2B like Example 1, the sample for measurement was produced, and glass composition and color tone data were calculated | required. The results are also summarized in Tables 2A-2B. The results show that, compared to the glass of the present invention, the glasses of Comparative Examples 2 to 4 are close to the conventional EG color or are bluish in excess.

Comparative Example 57
In the same manner as in Examples 8 to 14, glass bottles of each comparative example are manufactured using a continuous melting furnace with raw material mixing ratios shown in Tables 2B to 2C, samples for measurement are prepared, and glass compositions and color tone data I asked. The results are also summarized in Tables 2B-2C. The results show that, compared to the glass of the present invention, the glasses of Comparative Examples 5 to 7 are close to the conventional EG color.

From the results of the above example, in the continuous melting furnace of an electric furnace and a plant using gas fuel, although the amount of SO ₃ in glass obtained by the difference of the atmosphere (oxygen concentration) in the furnace is different as a whole, the manufacturing method of the present invention According to the above, it was confirmed that even if there is such a difference, it is possible to obtain a greenish-blue soda lime silica-based glass having a similar deep color and calm color.

According to the present invention, it is possible to stably and efficiently produce a greenish blue soda lime silica glass having a deep and calm color tone. In addition, the present invention provides a method of producing a greenish blue glass bottle, which enables utilization of up to 80% of cullet which has conventionally low recyclability, and further enables utilization of cullet in a total of 95%.

Claims (9)

In composition, in mass% indication,
Iron oxide 0.13-0.23% (Fe ₂ O ₃ conversion)
SO ₃ 0.07 to 0.17%
Chromium oxide 0.17 to 0.23% (Cr ₂ O ₃ equivalent)
Cobalt oxide 0.0023 to 0.010% (CoO conversion)
And cobalt oxide (CoO equivalent) / chromium oxide (Cr ₂ O ₃ equivalent) is 0.013 to 0.045.
Green-blue soda lime silica glass characterized in that In composition, in mass% indication,
Iron oxide 0.15 to 0.22% (Fe ₂ O ₃ conversion)
SO ₃ 0.08 to 0.13%
Chromium oxide 0.18 to 0.22% (Cr ₂ O ₃ equivalent)
Cobalt oxide 0.003 to 0.007% (CoO conversion)
And cobalt oxide (CoO equivalent) / chromium oxide (Cr ₂ O ₃ equivalent) is 0.015 to 0.040.
The green-blue soda lime silica glass according to claim 1, which is characterized in that In mass% display,
SiO ₂ 65-75%
Al ₂ O ₃ 0.5 to 5%
CaO 6-15%
MgO 0 to 4%
Na ₂ O 10 to 17%
K ₂ O 0 to 4%
Iron oxide 0.13-0.23% (Fe ₂ O ₃ conversion)
SO ₃ 0.07 to 0.17%
Chromium oxide 0.17 to 0.23% (Cr ₂ O ₃ equivalent)
Cobalt oxide 0.0023 to 0.010% (CoO conversion)
And cobalt oxide (CoO equivalent) / chromium oxide (Cr ₂ O ₃ equivalent) is 0.013 to 0.045.
The green-blue soda lime silica glass according to claim 1, which is characterized in that In mass% display,
SiO ₂ 68 to 74%
Al ₂ O ₃ 1 to 4%
CaO 8 to 13%
MgO 0.1 to 3%
Na ₂ O 11 to 15%
K ₂ O 0.1 to 3%
Iron oxide 0.15 to 0.22% (Fe ₂ O ₃ conversion)
SO ₃ 0.08 to 0.13%
Chromium oxide 0.18 to 0.22% (Cr ₂ O ₃ equivalent)
Cobalt oxide 0.003 to 0.007% (CoO conversion)
And cobalt oxide (CoO equivalent) / chromium oxide (Cr ₂ O ₃ equivalent) is 0.015 to 0.040.
The green-blue soda lime silica glass according to claim 1 or 2, characterized in that   The light emitting device according to any one of claims 1 to 4, wherein the lightness (Y) is 60 to 71%, the main wavelength (λd) is 546 to 556 nm, and the stimulation purity (Pe) is 10 to 21% in CIE indication (thickness 2 mm equivalent). Greenish blue soda lime silica glass.   The light emitting device according to any one of claims 1 to 4, wherein the lightness (Y) is 62 to 70%, the main wavelength (λd) is 548 to 555 nm, and the stimulation purity (Pe) is 12 to 18% in CIE indication (thickness 2 mm equivalent). Greenish blue soda lime silica glass.   A glass container formed by molding the greenish blue soda lime silica glass according to any one of claims 1 to 6. The cullet is prepared so that the total amount after vitrification is 100 parts by mass so that the used amount of cullet is 50 to 80 parts by mass and the total amount of cullet used is 75 to 95 parts by mass. A green-blue color characterized by adding a raw batch composition containing 10 to 0.25 parts by mass of potassium dichromate and 0.001 to 0.010 parts by mass of cobalt oxide (Co ₃ O ₄ ) Method of producing soda lime silica-based glass. The cullet is prepared so that the total amount after vitrification is 100 parts by mass so that the used amount of cullet used is 55 to 75 parts by mass and the total cullet used amount is 80 to 93 parts by mass. Claims: A raw batch composition comprising 11 to 0.24 parts by weight of potassium dichromate and 0.0020 to 0.0075 parts by weight of cobalt oxide (Co ₃ O ₄ ) is added. 8. A method of producing a greenish blue soda lime silica glass according to claim 8.