WO2011122500A1 - Procédé de production d'un verre polarisant - Google Patents

Procédé de production d'un verre polarisant Download PDF

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Publication number
WO2011122500A1
WO2011122500A1 PCT/JP2011/057472 JP2011057472W WO2011122500A1 WO 2011122500 A1 WO2011122500 A1 WO 2011122500A1 JP 2011057472 W JP2011057472 W JP 2011057472W WO 2011122500 A1 WO2011122500 A1 WO 2011122500A1
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WO
WIPO (PCT)
Prior art keywords
glass
stretching
manufacturing
polarizing glass
polarizing
Prior art date
Application number
PCT/JP2011/057472
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English (en)
Japanese (ja)
Inventor
拓朗 池田
浩三 前田
ひとみ 松本
Original Assignee
日本山村硝子株式会社
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Application filed by 日本山村硝子株式会社 filed Critical 日本山村硝子株式会社
Publication of WO2011122500A1 publication Critical patent/WO2011122500A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C4/00—Compositions for glass with special properties
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B23/00—Re-forming shaped glass
    • C03B23/02—Re-forming glass sheets
    • C03B23/037—Re-forming glass sheets by drawing
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B23/00—Re-forming shaped glass
    • C03B23/04—Re-forming tubes or rods
    • C03B23/047—Re-forming tubes or rods by drawing
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C14/00—Glass compositions containing a non-glass component, e.g. compositions containing fibres, filaments, whiskers, platelets, or the like, dispersed in a glass matrix
    • C03C14/004—Glass compositions containing a non-glass component, e.g. compositions containing fibres, filaments, whiskers, platelets, or the like, dispersed in a glass matrix the non-glass component being in the form of particles or flakes
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C2214/00—Nature of the non-vitreous component
    • C03C2214/04—Particles; Flakes

Definitions

  • the present invention relates to a method of manufacturing a polarizer used for an optical isolator, a liquid crystal display element or the like.
  • Patent Documents 1 and 2 disclose basic methods for producing a polarizer containing dispersed metallic silver particles having shape anisotropy.
  • shape-anisotropic silver halide grains are obtained by precipitating silver halide grains by heat treating glass containing Ag and halogen (Cl, Br or I) as components, and then extruding or stretching the glass. Then, the glass is dispersed and contained, and then is subjected to a reduction treatment to obtain a polarizing glass containing dispersed shape anisotropic metallic silver particles.
  • Patent Documents 3 and 4 show that the polarizing glass thus produced has a deviation in the angle of the polarization axis in the glass plate surface. However, Patent Documents 3 and 4 describe that the stretching stress and the temperature should be adjusted, but do not describe how to do it specifically.
  • Patent Document 5 in the stretching process, the temperature distribution of the heating furnace used for stretching is set so that the temperature becomes lower at both ends in the direction perpendicular to the stretching direction, so that the glass at the end in the width direction during stretching is set. A method for relatively increasing the cooling rate from the center is described.
  • Patent Document 6 describes a method of controlling the output of the heater in the stretching process so that the outer shape of the preform contracts at an inclination angle of 5 ° to 20 ° with respect to the longitudinal direction of the preform. Has been. In such a method, the heater device becomes long, the end portion of the preform cannot be effectively used, and the yield deteriorates.
  • Patent Document 7 in the stretching step, the stretching speed is maintained so that the angle formed by the side edges of the plate during stretching with respect to the stretching direction is less than 0.075 ° so that the width of the stretched glass becomes substantially constant. It describes that the film is stretched while being controlled. However, as specific means for that purpose, it is only described to synchronize the rotation of a pair of rollers for stretching and to change the rotation speed of the rollers according to the amount of the base glass.
  • Patent Document 8 describes a method of forcibly cooling only a central portion in the width direction by blowing a cooling gas from a nozzle on a glass sheet that is being stretched in a stretching process.
  • forced cooling has the problem of complicating the control of the device if heating and cooling are performed simultaneously.
  • the preform thickness is 3 mm or more
  • the movement speed of the preform is set to 15 mm / min or less
  • the take-up speed of the stretched glass sheet is set to 300 mm / min or less.
  • a production method characterized by heating and drawing is described. This method is a method of preventing the bending of the plate and does not reduce the in-plane distribution.
  • a glass composition containing Ag for manufacturing a polarizer for example, a glass containing, as a main component, SiO 2 , B 2 O 3 , Al 2 O 3 , alkali metal oxide (R 2 O), or the like is used. It is known to use a material to which halogen is added, for example, to use a glass in which metal halide particles are dispersed and contained (Patent Documents 1, 2, 10 to 14).
  • Patent Documents 3 to 9 are disclosed as methods for reducing the deviation of the angle of the polarization axis, but these require special temperature control or the like to be applied to the manufacturing process. Therefore, there is a problem that the process becomes complicated and the manufacturing cost is increased.
  • an object of the present invention is to provide a simpler method for reducing the deviation of the angle of the polarization axis in the obtained polarizing glass in the production of the polarizing glass.
  • the polarizing axis (absorption axis) of the stretched glass is in the stretching direction (that is, the direction in which the stretching load acts on the glass preform) as it is away from the center line as shown in FIG.
  • the present inventor confirmed that it shifted so as to spread obliquely outward.
  • the inventor further divides the stretching process into two or more stages as shown in FIG. 2, and stretches in the direction opposite to the stretching direction of the first stage in at least one of the plurality of stretching processes.
  • the deviation of the angle of the polarization axis can be eliminated or reduced.
  • the present invention has been completed by further studies based on this discovery.
  • Step (b) is repeated at least once, and in at least one of the repeated steps (b), the direction in which the glass is deformed is the first time in step (b) that the glass is deformed.
  • step (b) 2. 2. The production method according to 1 above, wherein the deformation of the glass in step (b) is performed by stretching. 3. 3. The production method according to 1 or 2 above, wherein step (b) is repeated once. 4). 4. In step (b), when the first draw ratio of the glass is n 1 and the second draw ratio is n 2 , n 1 / n 2 is 0.05 to 3.0. 4. Manufacturing method 5. The production method according to 4 above, wherein n 1 ⁇ n 2 is 5 or more. 6. The production method according to 4 or 5 above, wherein n 1 is 20 or less. 7). 7. The production method according to any one of 4 to 6 above, wherein the initial stretching stress in step (b) is 10 kgf / cm 2 or more. 8). 8.
  • the “polarization axis angle shift” means that the polarization at the portion of the polarizing glass increases as it moves away from the center line of the polarizing glass in the lateral direction (plus or minus direction) as shown in FIG. This means that the direction of the axis (absorption axis) is shifted obliquely with respect to the stretching direction.
  • FIG. 3 for the sake of convenience, the horizontal position from the center line of the polarizing glass is displayed with the right side of the drawing as plus and the left side as minus.
  • the magnitude [ ⁇ ] of the deviation of the angle of the polarization axis is indicated by the angle formed by the polarization axis with respect to the stretching direction. , Displays counterclockwise as positive and clockwise as negative.
  • the deviation of the angle of the polarization axis is a problem because there is a “variation” in the angle of the polarization axis depending on the position on the polarizing glass surface. Because. Therefore, the difference (absolute value) existing between the angles of the respective polarization axes at two distant points on the polarizing glass surface, or the polarization per unit length obtained by dividing this by the distance between the two points. The change in the angle of the axis is the actual object of evaluation.
  • various glass containing metal halide particles that can be reduced to metal particles can be used as the base glass.
  • a glass mainly composed of SiO 2 , B 2 O 3 , Al 2 O 3 , alkali metal oxide (R 2 O) or the like with Ag and halogen added can be used.
  • R 2 O alkali metal oxide
  • Patent Document 1 US Pat. No. 4,282,202
  • Patent Document 2 US Pat. No. 4,479,819
  • Patent Document 10 US Pat. No. 5,252,524
  • Patent Document 11 US Pat. No.
  • Patent Document 12 6,777,359 (Patent Document 12), US Pat. No. 7,468,148 (Patent Document 13), or US Pat. No. 7510989 (Patent Document 14), and used as the composition of the base glass in the present invention. However, it is not limited to them.
  • SiO 2 20 to 67% by weight
  • B 2 O 3 14 to 35% by weight
  • Al 2 O 3 0 to 25% by weight
  • P 2 O 5 0 to 25% by weight
  • Li 2 O + Na 2 O + K 2 O + Cs 2 O: 4 to 20% by weight can be suitably used as a base.
  • silver and halogen contained in these glasses include: Ag: 0.05 to 1.5% by weight, Cl + Br: more than the chemical equivalent of Ag, However, it is not limited to this range.
  • the applicant of the present application in an unpublished patent application (Japanese Patent Application No. 2009-136209), can use a glass having the following composition suitably for manufacturing a polarizer, and in particular, after stretching the glass, It has been confirmed that the reduction treatment can be performed in a short time in a hydrogen atmosphere of 1 atm.
  • R 1 represents Li, Na, K and Cs comprehensively, provided that Li 2 O: 0 to 5 wt%, Na 2 O: 0 to 9 wt%, K 2 O: 0 to 12 wt%, Cs 2 O: 0 to 6% by weight.
  • Cl 0.1 to 1.0% by weight
  • Br 0.01 to 0.5% by weight
  • F 0 to
  • the raw materials such as various oxides, halides, hydroxides, nitrates, sulfates and carbonates are prepared and melted using a known method so that the glass composition of the base material is in the above composition range.
  • the glass melt can be poured into a mold, molded, and heat treated to precipitate silver halide grains.
  • the step of deforming the glass is sufficient only two times, but the same effect can be obtained even if it is performed three times or more.
  • the last of the deformation steps has the greatest effect on the absorption maximum wavelength of the polarizing glass.
  • the stretching in the final stage is preferably performed at a temperature at which the glass has a viscosity of 10 6 to 10 9 Poise and a stress of 50 to 500 kgf / cm 2 .
  • the stretching is preferably performed so that the average aspect ratio (number average) of silver halide grains is at least 2: 1. There is no particular upper limit to the aspect ratio, and it can be set appropriately according to the purpose.
  • n 1 / n 2 is 0.05 to 3 when the stretching ratio in the first stretching is n 1 and the stretching ratio in the second stretching is n 2 .
  • 0 is preferable, 0.1 to 2.0 is more preferable, and 0.15 to 1.5 is still more preferable.
  • the stretching stress in the first stretching is small, the amount of deformation of the silver halide grains is small and the effect of stretching several times cannot be obtained, so the stretching stress in the first stretching (vertical stress in the stretching direction) is 10 kgf / cm 2 The above is preferable.
  • n 1 is preferably 1.25 or more, and 1.5 The above is more preferable, and 2.0 or more is still more preferable.
  • n 1 ⁇ n 2 is preferably 5 or more, more preferably 10 or more, and still more preferably 20 or more.
  • n 1 is preferably 20 or less, more preferably 15 or less, and even more preferably 10 or less.
  • FIG. 7 also shows the maximum value of the angle deviation of the polarization axis between various points in the plane of the polarizing glass thus superposed, and an element (optical isolator, liquid crystal) using the polarizing glass. It also shows the relationship with the limit value of the contrast ratio that can be secured over the entire surface of the display element or the like.
  • the absolute value of the difference in polarization axis angle between two points on the polarizing glass is preferably within 0.20 °, and is within 0.16 °. Is more preferable, and it is still more preferable that it is within 0.10 °. When these are converted into angles per unit length, they are within 0.01 ° / mm, within 0.008 ° / mm, and within 0.005 ° / mm, respectively.
  • the absolute value of the difference in the angle of the polarization axis between two points 20 mm apart is preferably 0.20 ° or less, and it is 0.16 ° between two points 15 mm apart. More preferably, it is more preferably 0.10 ° or less between two points 10 mm apart.
  • Example 1 ⁇ Manufacture of base glass> 49.8, B 2 O 3:: 21.3, Al 2 O 3: SiO 2 weight% 6.9, ZrO 2: 8.5, Li 2 O: 5.0, Na 2 O: 5.0 , K 2 O: 4.2, Ag: 0.43, Cl: 0.30, Br: 0.13, a base glass was prepared (represented as composition A in Table 1). That is, the raw materials mixed so as to give the respective compositions were melted at 1450 ° C. in a 2000 cc platinum crucible, then poured into a mold, and once cooled to below the glass transition point, a base glass block was obtained. The produced glass had a glass transition point of 503 ° C., a load softening point of 557 ° C. (measured by TMA), and a refractive index nd of 1.527.
  • the base glass block was heat-treated in an electric furnace maintained at 720 ° C. for 4 hours to produce a heat-treated base glass block.
  • This heat-treated base glass was cloudy white due to the precipitation of silver halide crystals.
  • the grain size of the precipitated silver halide crystals was measured for the heat-treated base glass.
  • the measurement procedure is as follows. That is, the heat-treated base glass was broken to obtain a smooth surface. The resulting smooth surface was etched with a 5 wt% HF aqueous solution for 15 seconds. A spherical hole formed by selectively dissolving the precipitated particle portion was observed with a scanning electron microscope (SEM). The average particle size (number average particle size) at this time was 130 nm.
  • the preform glass was processed into a plate shape having a width of 100 mm, a thickness of 4 mm, and a length of 800 mm.
  • ⁇ Reduction treatment> The stretched glass was cut into a length direction of 10 mm, precisely polished to a thickness of 0.2 mm, and subjected to hydrogen reduction treatment.
  • the reduction treatment was performed at 480 ° C. for 4 hours while flowing 100% hydrogen gas at a flow rate of 10 ml / min under atmospheric pressure.
  • ⁇ Evaluation of deviation of polarization axis angle> A collimator beam, which was linearly polarized through a Glan-Thompson prism, was incident on the polarizing glass, and the polarizing glass was rotated to record the angle at which the amount of transmitted light was minimized.
  • the polarization axis angle at the center of the plate is defined as 0 °, and the relative value of the polarization axis angle at each position in the width direction of the plate is defined as described above with reference to FIG.
  • stretching direction in FIG. 3 is an extending
  • Example 2 After the same preform as in Example 1 was stretched under the conditions shown in Table 1, reduction treatment and evaluation were performed in the same manner as in Example 1.
  • Tables 1 to 3 and FIGS. 4 to 6 show the stretching conditions and optical characteristics of Examples 1 to 6 and Comparative Examples 1 to 5 described above.
  • the present invention makes it easier to manufacture a polarizing glass with a significantly reduced polarization axis deviation as compared with the prior art, a polarizing glass with less deviation in the angle of the polarization axis is provided at a lower cost than before. enable.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Ceramic Engineering (AREA)
  • Dispersion Chemistry (AREA)
  • Polarising Elements (AREA)
  • Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)
  • Glass Compositions (AREA)

Abstract

Cette invention concerne un procédé de production d'un verre polarisant qui réduit la déviance de l'angle de l'axe de polarisation dans un verre polarisant, et qui est plus simple que le procédé classique. Le procédé selon l'invention comprend une étape (a) consistant à préparer un verre qui contient des particules dispersées d'halogénure métallique, une étape (b) consistant à obtenir un verre qui contient des particules dispersées et organisées d'un halogénure métallique à anisotropie de texture qui sont transformées dans une direction préconisée par application d'une charge sur ledit verre quand ce dernier est à l'état chauffé et ramolli, et une étape (c) consistant à réduire lesdites particules d'halogénure métallique à anisotropie de texture contenues dans le verre pour obtenir des particules métalliques à anisotropie de texture, l'étape (b) étant répétée au moins une fois, et lors au moins d'une répétition de ladite étape (b), la direction de transformation dudit verre est la direction opposée à celle dans laquelle ledit verre a été transformé la première fois que l'étape (b) a été mise en œuvre.
PCT/JP2011/057472 2010-03-29 2011-03-25 Procédé de production d'un verre polarisant WO2011122500A1 (fr)

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JP2010-075660 2010-03-29
JP2010075660A JP2013126921A (ja) 2010-03-29 2010-03-29 偏光ガラスの製造方法

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015198934A1 (fr) * 2014-06-26 2015-12-30 日本電気硝子株式会社 Plaque de verre polarisant et son procédé de fabrication, ensemble de plaque de verre polarisant pour isolateur optique et procédé de fabrication d'un élément optique pour isolateur optique
JP2016009164A (ja) * 2014-06-26 2016-01-18 日本電気硝子株式会社 偏光ガラス板、光アイソレータ用偏光ガラス板セット及び光アイソレータ用光学素子の製造方法
JP2016038500A (ja) * 2014-08-08 2016-03-22 日本電気硝子株式会社 偏光ガラス板の製造方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106320345A (zh) * 2015-06-30 2017-01-11 上海勘测设计研究院有限公司 基坑围护结构

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003261357A (ja) * 2002-01-24 2003-09-16 Corning Inc 偏光ガラスの製造方法
JP2006221166A (ja) * 2005-02-11 2006-08-24 Arisawa Mfg Co Ltd 偏光ガラス、及び偏光ガラスの製造方法
JP2008299329A (ja) * 2007-05-29 2008-12-11 Ｈｏｙａ Ｃａｎｄｅｏ Ｏｐｔｒｏｎｉｃｓ株式会社 偏光ガラスの製造方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003261357A (ja) * 2002-01-24 2003-09-16 Corning Inc 偏光ガラスの製造方法
JP2006221166A (ja) * 2005-02-11 2006-08-24 Arisawa Mfg Co Ltd 偏光ガラス、及び偏光ガラスの製造方法
JP2008299329A (ja) * 2007-05-29 2008-12-11 Ｈｏｙａ Ｃａｎｄｅｏ Ｏｐｔｒｏｎｉｃｓ株式会社 偏光ガラスの製造方法

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015198934A1 (fr) * 2014-06-26 2015-12-30 日本電気硝子株式会社 Plaque de verre polarisant et son procédé de fabrication, ensemble de plaque de verre polarisant pour isolateur optique et procédé de fabrication d'un élément optique pour isolateur optique
JP2016009164A (ja) * 2014-06-26 2016-01-18 日本電気硝子株式会社 偏光ガラス板、光アイソレータ用偏光ガラス板セット及び光アイソレータ用光学素子の製造方法
CN106461849A (zh) * 2014-06-26 2017-02-22 日本电气硝子株式会社 偏振玻璃板及其制造方法、光隔离器用偏振玻璃板组以及光隔离器用光学元件的制造方法
US10202298B2 (en) 2014-06-26 2019-02-12 Nippon Electric Glass Co., Ltd. Polarizing glass plate and method for manufacturing same, polarizing glass plate set for optical isolator, and method for manufacturing optical element for optical isolator
CN106461849B (zh) * 2014-06-26 2019-04-19 日本电气硝子株式会社 偏振玻璃板的制造方法
US11365145B2 (en) 2014-06-26 2022-06-21 Nippon Electric Glass Co., Ltd. Polarizing glass sheet set for optical isolator and method for manufacturing optical element for optical isolator
JP2016038500A (ja) * 2014-08-08 2016-03-22 日本電気硝子株式会社 偏光ガラス板の製造方法

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