TW201438893A - Glass laminate, optical imaging member, and method of manufacturing the same and glass plate - Google Patents

Abstract

A laminate, which can narrow and uniformize a spacing of a reflecting surface and does not cause rising cost, is provided. By providing the laminate, an optical imaging member, which can form an image in high resolution, can be obtained. A glass laminate 1 of the invention is laminated by a glass plate 10 with a thickness equal to or less than 500 μ m and is characterized by having a reflecting film 11 between the glass plates 10.

Description

Glass laminate, optical imaging member, method for producing glass laminate, and method for producing optical imaging member

The present invention relates to a glass laminate, an optical imaging member, a method for producing a glass laminate, and a method for fabricating an optical imaging member, and is, for example, related to use in a liquid crystal display, organic electroluminescence. (Electroluminescence, EL) A glass laminate produced by a flat panel display such as a flat panel display, an optical imaging member, a method for producing a glass laminate, and a method for producing an optical imaging member.

As is well known, flat panel displays such as liquid crystal displays, plasma displays, and organic EL displays are becoming popular based on the viewpoint of space saving.

Moreover, the development of technology for imaging light generated by flat panel displays in the air is being advanced. Patent Document 1 proposes an optical imaging member in which a plurality of double-sided reflective strips are arranged at regular intervals so that adjacent reflecting surfaces face each other. However, the optical imaging member disclosed in Patent Document 1 has the following problems: After the scattered light passes, it does not necessarily converge at a point.

Prior art literature

Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. SHO 58-21702

In order to solve the above problems, an optical imaging member has been developed in which a plurality of transparent plates having a single reflecting surface are laminated, and then cut so as to form a cut surface perpendicular to each reflecting surface, thereby producing A pair of laminated bodies are formed, and then the pair of laminated bodies are relatively closely contacted so that the reflecting surfaces formed on the other laminated body are orthogonal to each other with respect to the reflecting surface formed on one laminated body. In the optical imaging member, the thickness of the transparent plate corresponds to the interval of the reflecting surface.

In the case of the above-described optical imaging member, in order to obtain high-resolution imaging, it is necessary to make the thickness of the transparent plate uniform and thin, but such a transparent plate is difficult to manufacture, and it is a cause of an increase in cost.

The present invention has been made in view of the above circumstances, and it is possible to obtain an optical imaging member capable of high-resolution imaging by creating a laminated body in which the interval between the reflecting surfaces can be narrowed and uniformized without causing an increase in cost.

As a result of intensive studies, the present inventors have found that a glass laminate which is formed by interposing a reflective film between glass sheets and integrating them is applied to an optical imaging member, thereby solving the above technical problems and as the present invention. And put forward. In other words, the glass laminate of the present invention is a glass laminate obtained by laminating glass sheets having a thickness of 500 μm or less, and has a reflection film between the glass sheets.

In the glass laminate of the present invention, the thickness of the glass plate is 500 μm or less. Here, the glass plate having a thickness of 500 μm or less includes a so-called glass film having a thickness of 300 μm or less (the same applies hereinafter). Thus, the interval of the reflective film is narrowed, and thus high-resolution imaging can be easily obtained. Further, since the glass plate having a thickness of 500 μm or less is easy to improve the surface smoothness and the thickness unevenness can be reduced, the reflective film can be formed on the surface with high precision, and the laminated layer can be appropriately integrated. Thereby, the interval of the reflecting surface can be narrowed and uniformized without causing an increase in cost.

Secondly, in the glass laminate of the present invention, it is preferred to laminate a strip of glass Glass plate. As such, it can be easily applied to an optical imaging member. Here, the "strip-shaped glass plate" means that the ratio of the length dimension/width dimension of the glass plate is 5 or more. Furthermore, "length dimension" refers to the longer of the longitudinal dimension and the lateral dimension, and "width dimension" refers to the shorter of the longitudinal dimension and the lateral dimension.

Thirdly, in the glass laminate of the present invention, it is preferred to laminate a glass plate having a reflection film formed on at least one surface.

Fourthly, in the glass laminate of the present invention, the surface roughness Ra of the surface of the glass plate is preferably 100 Å or less. Here, "surface roughness Ra" means a value measured by a method according to JIS B0601:2001.

Fifth, in the glass laminate of the present invention, it is preferred that the glass sheet has a undulation of 1 μm or less. Here, "undulation" refers to a value obtained by measuring a WCA (filter center line undulation) described in JIS B0601:2001 using a stylus type surface shape measuring device, which is According to SEMI STD D15-1296 The method of "measuring method of surface undulation of a flat panel display (FPD) glass substrate" was measured, and the cutoff at the time of measurement was 0.8 mm - 8 mm, and it was perpendicular with respect to the pull-out direction of a glass plate. The direction was measured at a length of 300 mm.

Sixth, in the glass laminate of the present invention, it is preferable that the difference between the maximum thickness and the minimum thickness of the glass sheet is 20 μm or less. Here, the "difference between the maximum thickness and the minimum thickness of the glass plate" means a value obtained by scanning a laser from either side of the glass plate from the thickness direction using a laser thickness measuring device. Thereby, the maximum thickness and the minimum thickness of the glass sheet are measured, and the value obtained by subtracting the value of the minimum thickness from the value of the maximum thickness.

Seventh, in the glass laminate of the present invention, it is preferred that the glass sheet has an unpolished surface.

Eighth, in the glass laminate of the present invention, it is preferred that the glass sheet has a length of 500 mm or less.

Ninth, in the glass laminate of the present invention, it is preferred that the glass sheet is formed by an overflow down draw method.

Tenth, in the glass laminate of the present invention, it is preferred to have a bonding layer between the glass sheets, and the thickness of the bonding layer is 100 μm or less. If a bonding layer is provided, it is easy to integrate the glass sheets. Further, if the thickness of the adhesive layer is lowered, the interval between the reflective films is easily narrowed.

Eleventh, in the glass laminate of the present invention, it is preferred that the reflective film be Al or Ag. These reflective films are advantageous from the viewpoint of obtaining high-resolution imaging.

Twelfth, the optical imaging member of the present invention includes a pair of glass laminates The optical imaging member is characterized in that each of the pair of glass laminates is any one of the above-mentioned glass laminates, and the pair of glass laminates are disposed such that the surfaces on which the reflection films are formed are orthogonal to each other.

Thirteenth, in the optical imaging member of the present invention, preferably in a pair of glasses The laminated outer surface (usually the end surface side of the glass plate) of the laminated body is disposed with a cover glass plate. Here, the cover glass plate refers to a glass plate (including a so-called glass film) covering the outer surface of the laminated layers of the pair of glass laminates (the same applies hereinafter). Further, the cover glass plate may cover at least one of the laminated outer surfaces of the pair of glass laminates.

Fourteenth, in the optical imaging member of the present invention, preferably in the cover glass An outer surface of the plate is formed with an anti-reflection film.

Fifteenth, the method for producing a glass laminate of the present invention is characterized by The method of preparing a glass plate with a reflective film, wherein the glass plate with a reflective film is formed with a reflective film on at least one surface of a glass plate having a thickness of 500 μm or less; and integrating the glass plate with a reflective film to obtain The step of the glass laminate.

Sixteenth, in the method for producing a glass laminate according to the present invention, it is preferred to borrow The glass sheet with the reflective film is laminated by a binder.

Seventeenth, in the method for producing a glass laminate of the present invention, it is preferably The glass plate with a reflective film is laminated and integrated under pressure.

Eighteenth, the method for producing a glass laminate of the present invention is characterized by A glass laminate in which a glass plate with a reflective film is integrated is formed in a direction orthogonal to a surface on which a reflective film is formed (usually a thickness direction of a glass plate). The step of breaking into strips.

Nineteenth, in the method for producing a glass laminate of the present invention, preferably The glass laminate was cut with a wire saw.

Twentyth, in the method for producing a glass laminate of the present invention, preferably The wire saw was cut in a state where the surface of the glass plate of the glass laminate was limited to an angle of 45 or less.

Twenty-first, the method of manufacturing the optical imaging member of the present invention is characterized by The method includes the steps of: preparing a pair of glass laminates by integrating a glass sheet with a reflective film; and arranging a pair of glass laminates so that surfaces on which the reflective film is formed are orthogonal to each other Thereby obtaining the step of the optical imaging member.

Twenty-second, in the method of manufacturing the optical imaging member of the present invention, preferably It is a strip of a pair of glass laminates. Here, the "strip-shaped glass laminate" refers to a glass plate having a ratio of a length dimension/width dimension of 5 or more laminated on the basis of a glass plate.

Twenty-third, the method of manufacturing the optical imaging member of the present invention is preferably more The method includes the step of disposing a glass plate on a laminated outer surface of a pair of glass laminates.

Twenty-fourth, the method of manufacturing the optical imaging member of the present invention is characterized by The method comprising: forming a reflective film on at least one surface of a glass plate having a thickness of 500 μm or less to obtain a glass plate with a reflective film; and integrating a glass plate with a reflective film to obtain a glass laminate; and The step of forming a pair of glass laminates in such a manner that the faces on which the reflective films are formed are orthogonal to each other, thereby obtaining the optical imaging member.

Twenty-fifth, the glass plate of the present invention is characterized in that the thickness is 500 μm Hereinafter, a reflective film is formed on at least one surface.

Twenty-sixth, the glass plate of the present invention is characterized in that the thickness is 500 μm Hereinafter, the transmittance at a wavelength of 350 nm in terms of a thickness of 500 μm is 70% or more, and the glass plate is used for a glass laminate. Further, the transmittance can be measured by a commercially available transmittance measuring device.

1‧‧‧glass laminate

2‧‧‧glass laminate

3‧‧‧Optical imaging components

4‧‧‧Optical imaging components

10‧‧‧ glass film

11‧‧‧Reflective film

12‧‧‧ glass film

13‧‧‧Reflective film

14‧‧‧Reflective film

15‧‧‧glass plate (glass film)

16‧‧‧Flating glass panels

21‧‧‧Glass film with reflective film

22‧‧‧Attraction device

23‧‧‧ Coating device

24‧‧‧glass laminate

25‧‧‧roll

26‧‧‧Glass film with reflective film

27‧‧‧Glass laminate

31‧‧‧Glass laminate

32‧‧‧ wire saw

33‧‧‧Glass laminate

Fig. 1 is a conceptual perspective view showing an example of a glass laminate according to the present invention.

Fig. 2 is a conceptual perspective view showing an example of a glass laminate according to the present invention.

Fig. 3 is a conceptual perspective view showing an example of an optical imaging member of the present invention.

Fig. 4 is a conceptual perspective view showing an example of an optical imaging member of the present invention.

Fig. 5a is a conceptual cross-sectional view showing an example of a method of integrating a glass sheet with a reflection film.

Fig. 5b is a conceptual cross-sectional view showing an example of a method of integrating a glass sheet with a reflection film.

Fig. 5c is a conceptual cross-sectional view showing an example of a method of integrating a glass plate with a reflection film.

Fig. 6a is a conceptual explanatory view showing an example of a method of cutting a large-sized glass laminate into a strip shape by a wire saw.

Fig. 6b is a conceptual explanatory view showing an example of a method of cutting a large-sized glass laminate into a strip shape by a wire saw.

Fig. 6c is a conceptual explanatory view showing an example of a method of cutting a large-sized glass laminate into a strip shape by a wire saw.

In the glass laminate of the present invention, the glass plate has a thickness of 500 μm or less, preferably 300 μm or less, 200 μm or less, 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, 40 μm or less, and 30 μm. The glass film of the following or 1 μm to 20 μm is particularly preferably a glass film having a thickness of 5 μm to 10 μm. The thinner the thickness of the glass plate, the narrower the interval between the reflective films, and thus it is easy to obtain high-resolution imaging.

The surface roughness Ra of the surface of the glass plate is preferably 100 Å or less, 50 Å or less, 10 Å or less, 8 Å or less, 4 Å or less, or 3 Å or less, and particularly 0.01 Å to 2 Å. When the surface roughness Ra of the surface of the glass plate is too large, the interval of the reflective film tends to become uneven, and in particular, when the glass plate is laminated, the unevenness of the interval of the reflective film is amplified, and it is difficult to obtain a high resolution. Imaging. Further, when the glass plate is laminated, air is easily caught or optical bonding is difficult.

The surface roughness Ra of the end surface of the glass film is preferably 100 Å or less, 50 Å or less, 10 Å or less, 8 Å or less, 4 Å or less, or 3 Å or less, and particularly preferably 0.1 Å to 2 Å. When the surface roughness Ra of the end surface of the glass plate is too large, the glass laminate tends to be easily broken.

The undulation of the glass plate is preferably 1 μm or less, 0.08 μm or less, 0.05 μm or less, 0.03 μm or less, or 0.02 μm or less, and particularly preferably 0.01 μm or less. If the undulation of the glass plate is too large, the interval of the reflective film tends to become uneven, especially in the case of glass. When the laminated layers are integrated, the unevenness of the interval of the reflective film is amplified, so that it is difficult to obtain high-resolution imaging. Further, when the glass plate is laminated, air is easily caught or optical bonding is difficult.

The difference between the maximum thickness and the minimum thickness of the glass plate is preferably 10 μm or less. 5 μm or less or 2 μm or less, particularly preferably 0.01 μm to 1 μm. When the difference is too large, the interval between the reflective films tends to be uneven, and in particular, when the glass sheets are laminated, the unevenness of the interval of the reflective films is amplified, and it is difficult to obtain high-resolution imaging. Further, when the glass plate is laminated, air is easily caught or optical bonding is difficult.

The glass sheet preferably has an unground surface. The theoretical strength of the glass Very high, but many of them cause damage under stresses far below the theoretical strength. This is because, in the post-forming step of the glass, for example, the grinding step or the like, a small defect called a Griffith flaw is generated on the surface of the glass sheet. Therefore, if the surface of the glass plate is not polished, it is difficult to impair the original mechanical strength, and the glass plate becomes difficult to be broken. Moreover, since the polishing step can be omitted, the manufacturing cost of the glass sheet can be reduced. Further, if the entire effective surface of both surfaces of the glass sheet is an unpolished surface, the glass sheet becomes more difficult to be broken.

The length of the glass plate is preferably 500 mm or more and 600 mm or more. 800mm or more, 1000mm or more, 1200mm or more, or 1500mm or more, and more preferably 2000mm or more. In this way, it is easy to increase the size of the optical imaging member. On the other hand, if the length dimension of the glass plate is too large, it is difficult to cut the glass laminate in a direction orthogonal to the surface on which the reflective film is formed. Therefore, the length of the glass plate is preferably 3,500 mm or less or 3,200 mm or less, and more preferably 3,000 mm or less.

The width of the glass plate is not limited to the length dimension. In the case of processing into a strip-shaped glass laminate, the ratio of the length dimension to the width dimension is 5 or more, preferably 10 or more, 20 or more, 30 or more, 40 or more, 50 or more, or 60 or more, and particularly preferably 100~2000. If the ratio of the length dimension/width dimension is too small, the manufacturing efficiency of the optical imaging member is liable to decrease.

The glass sheet is preferably formed by an overflow down-draw method. So, you can make a research A glass plate with a good surface quality. The reason for this is that, in the case of the overflow down-draw method, the surface of the glass sheet to be the surface does not contact the groove-shaped refractory, but is formed in a state of a free surface. Here, the overflow down-draw method refers to a method of causing the molten glass to overflow from both sides of the heat-resistant groove-like structure, so that the overflowed molten glass converges at the lower end of the groove-like structure, and simultaneously The lower extension is formed to produce a glass plate. The structure or material of the groove-like structure is not particularly limited as long as the size or surface precision of the glass plate can be made into a desired state, and the quality of the glass plate can be achieved. Further, in order to perform the stretch forming toward the lower side, it is possible to apply a force to the glass by any method. For example, a method in which a heat-resistant roll having a sufficiently large width is rotated in a state of contacting the glass to extend the glass may be employed, and a plurality of pairs of heat-resistant rolls may be used only in contact with the end face of the glass. A method of extending the glass. Further, in addition to the overflow down-draw method, for example, a forming method such as a slot down method or a redraw method may be employed.

In the case of forming by the overflow down-draw method, the viscosity of the glass which becomes a non-contact portion (lower tip portion) from the groove-shaped refractory is preferably 10 ^3.5 dPa. s~10 ^5.0 dPa. s. If no force is applied to the lower end portion of the groove-like structure, it will shrink while falling due to the surface tension. In order to prevent this, it is necessary to use the components on the roll to sandwich both sides of the glass blank and stretch along the width to prevent the glass blank from shrinking. When a glass plate having a thickness of 500 μ or less is formed, since the heat of the glass itself is small, the cooling rate of the glass is rapidly increased from the moment of leaving the groove-shaped refractory. Therefore, the viscosity of the glass at the lower tip portion is preferably 10 ^5.0 dPa. s below, 10 ^4.8 dPa. s below, 10 ^4.6 dPa. s below, 10 ^4.4 dPa. s below or 10 ^4.2 dPa. Below s, especially good for 10 ^4.0 dPa. s below. In this way, tensile stress can be imparted in the width direction to prevent breakage, and the width can be widened and can be stably extended downward. On the other hand, if the viscosity of the glass at the lower end portion is too low, the glass is easily deformed, and the quality such as warpage and undulation is likely to be lowered. Moreover, the subsequent cooling rate becomes faster, and the heat shrinkage of the glass sheet tends to become large. Therefore, the viscosity of the glass at the lower tip portion is preferably 10 ^3.5 dPa. Above s, 10 ^3.7 dPa. s above or 10 ^3.8 dPa. Above s, especially preferably 10 ^3.9 dPa. s above.

The crack rate of the glass plate is preferably 70% or less and 50%. Lower, 40% or less or 30% or less, and particularly preferably 20% or less. As a result, the glass laminate becomes difficult to break. Here, the "crack generation rate" refers to a value of a Vickers indenter set to a load of 1000 g in a constant temperature and humidity chamber maintained at a humidity of 30% and a temperature of 25 ° C. Pressing into the glass surface (optical grinding equivalent) for 15 seconds, counting the number of cracks generated from the 4 corners of the indentation after 15 seconds (up to 4 cracks per indentation), This operation was repeated 20 times (i.e., the indenter was pressed 20 times), and after the total number of cracks was counted, the value obtained by the total crack generation number /80 was obtained.

The liquidus temperature of the glass plate is preferably 1200 ° C or less, 1150 ° C or less, 1130 ° C or less, 1110 ° C or less, or 1090 ° C or less, and more preferably 700 ° C to 1070 ° C. The liquid viscosity of the glass plate is preferably 10 ^5.0 dPa. Above s, 10 ^5.6 dPa. s above or 10 ^5.8 dPa. Above s, especially preferably 10 ^6.0 dPa. s~10 ^10.0 dPa. s above. Thus, the glass is hard to devitrify during molding. Further, the "liquidus temperature" means a value as follows: a glass powder which has passed through a standard sieve of 30 mesh (500 μm) and remains at 50 mesh (300 μm) is placed in a platinum boat. The value obtained by measuring the temperature at which the crystal was precipitated was maintained in a temperature gradient furnace for 24 hours. The "liquid phase viscosity" refers to a value obtained by measuring the viscosity of glass at a liquidus temperature by a platinum ball pulling method.

The Young's modulus of the glass plate is preferably 65 GPa or more, 67 GPa or more, 68 GPa or more, 69 GPa or more, 70 GPa or more, 71 GPa or more, or 72 GPa or more, and particularly preferably 75 GPa to 100 GPa. As described above, after the reflective film is formed on the surface of the glass plate, the glass plate is less likely to warp, and as a result, the interval between the reflective films is less likely to become uneven, and high-resolution imaging can be easily obtained. In addition, "Young's modulus" means a value measured by a resonance method.

The density of the glass plate is preferably 2.7 g/cm ³ or less, 2.6 g/cm ³ or less, or 2.5 g/cm ³ or less, and particularly preferably 2.0 g/cm ³ to 2.4 g/cm ³ . In this way, it is easy to achieve weight reduction of the optical imaging member.

The thermal expansion coefficient of the glass plate is preferably 25 × 10 ^-7 / ° C ~ 100 × 10 ^-7 / ° C, 30 × 10 ^-7 / ° C ~ 90 × 10 ^-7 / ° C, 30 × 10 ^-7 / ° C ~ 60 × 10 ^-7 /°C or 30×10 ^-7 /°C~45×10 ^-7 /°C, especially preferably 30×10 ^-7 /°C~40×10 ^-7 /°C. Thus, it is easy to match the thermal expansion coefficients of various functional films. In addition, the "thermal expansion coefficient" is a value obtained by measuring the average thermal expansion coefficient at 30 ° C to 380 ° C using a dilatometer, and the sample for measuring the thermal expansion coefficient is chamfered using the end surface. A cylindrical sample of φ 5 mm × 20 mm.

The strain point of the glass plate is preferably 600 ° C or more, and particularly preferably 630 ° C ~ 750 ° C. Thus, it is easy to improve heat resistance. Further, the "strain point" refers to a value measured based on the method of ASTM C336-71.

Transmittance at a wavelength of 300 nm in terms of a thickness of a glass plate of 500 μm It is preferably 30% or more, 50% or more, 70% or more, 80% or more, or 85% or more, and particularly preferably 89% to 99%. Further, the transmittance at a wavelength of 350 nm in terms of a thickness of 500 μm is preferably 50% or more, 70% or more, 80% or more, 85% or more, 89% or more, or 90% or more, and particularly preferably 91% or more. Further, the transmittance at a wavelength of 550 nm in terms of a thickness of 500 μm is 85% or more, 89% or more, or 90% or more, and particularly preferably 91% to 99%. As described above, when applied to an optical imaging member or the like, when light is transmitted while being reflected and reflected, the loss of light is reduced, and high-resolution imaging can be easily obtained.

The haze of the glass plate is preferably 10% or less, 5% or less, and 3%. The following is 1% or less or 0.5% or less, and particularly preferably 0.3% or less. In this way, the diffuse reflection on the surface can be alleviated, and when applied to an optical imaging member or the like, when light is transmitted while being reflected and reflected, the loss of light is reduced, and high-resolution imaging can be easily obtained. Further, "haze" can be measured using a commercially available haze meter.

As the glass composition, the glass plate preferably contains 35% to 80% of SiO ₂ , 0% to 20% of Al ₂ O ₃ , 0% to 17% of B ₂ O ₃ , and 0% to 10% by mass%. MgO, 0% to 15% CaO, 0% to 15% SrO, 0% to 30% BaO. The reason for limiting the content range of each component as described above will be described below. Further, in the description relating to the glass composition, the % symbol means mass%.

The content of SiO ₂ is preferably from 35% to 80%. When the content of SiO ₂ is too large, the meltability and moldability are liable to lower. Therefore, the content of SiO ₂ is preferably 75% or less, 64% or less, or 62% or less, and particularly preferably 61% or less. On the other hand, when the content of SiO ₂ is too small, it is difficult to form a glass network structure, and it becomes difficult to vitrify, or the generation rate of cracks may become high, or acid resistance may fall easily. Therefore, the content of SiO ₂ is preferably 40% or more, 50% or more, or 55% or more, and particularly preferably 57% or more.

The content of Al ₂ O ₃ is preferably from 0% to 20%. When the content of Al ₂ O ₃ is too large, devitrified crystals are precipitated in the glass, and the liquid phase viscosity is liable to lower. The content of Al ₂ O ₃ is preferably 18% or less or 17.5% or less, and particularly preferably 17% or less. On the other hand, when the content of Al ₂ O ₃ is too small, the strain point and the Young's modulus are liable to lower. Therefore, the content of Al ₂ O ₃ is preferably 3% or more, 5% or more, 8.5% or more, 10% or more, 12% or more, 13% or more, 13.5% or more, or 14% or more, and particularly preferably 14.5% or more.

The content of B ₂ O ₃ is preferably from 0% to 17%. When the content of B ₂ O ₃ is too large, the strain point, Young's modulus, and acid resistance are liable to lower. Therefore, the content of B ₂ O ₃ is preferably 15% or less, 13% or less, 12% or less, or 11% or less, and particularly preferably 10.4% or less. On the other hand, when the content of B ₂ O ₃ is too small, the high-temperature viscosity is increased, the meltability is lowered, the crack generation rate is increased, or the liquidus temperature is increased, or the density is likely to be high. Therefore, the content of B ₂ O ₃ is preferably 2% or more, 3% or more, 4% or more, 5% or more, 7% or more, 8.5% or more, or 8.8% or more, and particularly preferably 9% or more.

MgO is to increase Young's modulus, strain point, and reduce high temperature viscosity, crack The composition of the seam production rate. However, when the content of MgO is too large, the liquidus temperature rises, and the devitrification resistance is liable to lower. In addition, the buffered hydrofluoric acid (BHF) is liable to lower. Therefore, the content of MgO is preferably 10% or less, 5% or less, 3% or less, 2% or less, 1.5% or less, or 1% or less, and particularly preferably 0.5% or less.

The content of CaO is preferably from 0% to 15%. If the content of CaO is too much, then The density and thermal expansion coefficient tend to become high. Therefore, the content of CaO is preferably 12% or less, 10% or less, or 9% or less, and particularly preferably 8.5% or less. On the other hand, when the content of CaO is too small, the meltability and the Young's modulus are liable to lower. Therefore, the content of CaO is preferably 2% or more, 3% or more, 5% or more, 6% or more, or 7% or more, and particularly preferably 7.5% or more.

The content of SrO is preferably from 0% to 15%. If the content of SrO is too much, it is dense The degree of thermal expansion is likely to become high. Therefore, the content of SrO is preferably 12% or less, 10% or less, 6% or less, or 5% or less, and particularly preferably 6.5% or less. On the other hand, when the content of SrO is too small, the meltability and chemical resistance are liable to lower. Therefore, the content of SrO is preferably 0.5% or more, 1% or more, 2% or more, or 3% or more, and particularly preferably 3.5% or more.

When the content of BaO is too large, the density and thermal expansion coefficient tend to be high. because Further, the content of BaO is preferably 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, 5% or less, 2% or less or 1% or less, and particularly preferably 0.5% or less.

If a plurality of components of each of MgO, CaO, SrO, and BaO are introduced, Then, the liquidus temperature is lowered, so that it is difficult to generate crystal foreign matter in the glass. On the other hand, when the total content of these components is too small, the function as a flux cannot be sufficiently exhibited, and the meltability is liable to lower. Therefore, the total content of these components is preferably 5% or more, 8% or more, 9% or more, or 11% or more, and particularly preferably 13% or more. On the other hand, when the total content of these components is too large, the density is increased, and it is difficult to reduce the weight of the glass, and the crack occurrence rate tends to be high. Therefore, the total content of the components is preferably 30% or less, 20% or less, or 18% or less, and particularly preferably 15% or less. In particular, when it is desired to lower the density of the glass film, the total content of the components is preferably 5% or more, particularly preferably 8% or more, and preferably 13% or less or 11% or less. Good is less than 10%.

ZnO is a component that increases the meltability and Young's modulus. However, if ZnO If the content is too much, the glass will be devitrified, or the strain point will decrease, or the density will rise easily. Therefore, the content of ZnO is preferably 15% or less, 10% or less, 5% or less, 3% or less, or 1% or less, and particularly preferably 0.5% or less.

ZrO ₂ is a component that increases the Young's modulus. However, when the content of ZrO ₂ is too large, the liquidus temperature rises, and devitrified foreign matter of zircon is likely to be generated. Therefore, the content of ZrO ₂ is preferably 3% or less, 1% or less, or 0.5% or less, and particularly preferably 0.1% or less.

The upper limit content of Fe ₂ O ₃ is preferably 1000 ppm (0.1%) or less, 800 ppm or less, 300 ppm or less, 200 ppm or less, 130 ppm or less, 100 ppm or less, 80 ppm or less, 60 ppm or less, 40 ppm or less, 30 ppm or less, or 20 ppm or less. The content of the lower limit is preferably 1 ppm or more, and more preferably 3 ppm or more. The smaller the content of Fe ₂ O ₃ is, the higher the transmittance is. Therefore, when applied to an optical imaging member or the like, when light is transmitted while being reflected and reflected, the loss of light is reduced, and high resolution is easily obtained. Degree of imaging. Further, in order to lower the content of Fe ₂ O ₃ , it is preferred to use a raw material of high purity.

Y ₂ O ₃ , Nb ₂ O ₃ , and La ₂ O ₃ are components for increasing the strain point, Young's modulus, and the like. However, if the content of these components is too large, the density tends to be high. Therefore, the content of Y ₂ O ₃ , Nb ₂ O ₃ , and La ₂ O ₃ is preferably 3% or less.

As the clarifying agent, one or two or more selected from the group consisting of As ₂ O ₃ , Sb ₂ O ₃ , CeO ₂ , SnO ₂ , F, Cl, and SO ₃ may be added in an amount of 0% to 3%. Among them, from the viewpoint of the environment, it is preferred to control the use of As ₂ O ₃ , Sb ₂ O ₃ and F, especially As ₂ O ₃ and Sb ₂ O ₃ , preferably limiting the respective contents to less than 0.1%. . Preferred fining agents are SnO ₂ , SO ₃ and Cl. The content of SnO ₂ is preferably from 0% to 1% or from 0.01% to 0.5%, particularly preferably from 0.05% to 0.4%. Further, the content of SnO ₂ +SO ₃ +Cl (the total content of SnO ₂ , SO ₃ and Cl) is preferably 0.001% to 1% or 0.01% to 0.5%, particularly preferably 0.01% to 0.3%.

In addition to the above ingredients, other ingredients may be added, including other ingredients. The amount is 10% or less, and particularly preferably 5% or less.

The glass laminate of the present invention is preferably laminated to have at least one surface shape A glass plate having a reflective film. Thus, it is easy to reduce the manufacturing cost of a glass laminated body. Further, from the viewpoint of film formation efficiency, it is more preferable to laminate a glass plate in which a reflection film is formed only on one surface.

Various materials can be used for the reflective film, but among them, high resolution is obtained. From the viewpoint of the image, it is preferably Al or Ag.

There are various methods for forming a reflective film on the surface of a glass plate, and examples thereof include vapor deposition, sputtering, and plating. In particular, from the viewpoint of film formation efficiency, it is preferred to form a reflection film by sputtering.

In the case where a reflective film (particularly, a reflective film of Al) is formed by sputtering or vapor deposition, it is preferred to electrolytically polish the reflective film. Thus, the positive reflectance of the reflective film is improved, and the image quality of the imaged image can be improved.

For the surface of the glass plate, a resin film with a reflective film is also preferred. Thus, the formation cost of the reflective film can be reduced.

After coating a metal paste such as an paste or an Ag paste on a surface of a glass plate and drying it, it is also preferable to laminate and calcine the obtained glass plate, and it is preferable to contain a glass frit in the metal paste ( Glass frit). In this way, the fixation of the glass sheets and the formation of the reflective film can be simultaneously performed.

A protective film such as SiO ₂ may be formed on the reflective film as needed. Thus, the reflective film can be appropriately protected.

In the glass laminate of the present invention, the number of laminated sheets of the glass sheet is preferably 100 sheets or more, 200 sheets or more, 300 sheets or more, 400 sheets or more, 500 sheets or more, or 600 sheets or more, and more preferably 700 sheets or more. The larger the number of laminated sheets of the glass film, the easier it is to produce a large-sized optical imaging member.

The glass laminate of the present invention preferably integrates the glass sheets with each other by a binder. That is, it is preferred to have a bonding layer between the glass sheets. In this way, the glass sheets can be firmly integrated with each other. Moreover, the thickness of the bonding layer is preferably 100 μm. Hereinafter, it is 70 μm or less, 50 μm or less, or 40 μm or less, and particularly preferably 30 μm or less. Thus, it is easy to narrow the interval of the reflective film. Further, as the binder, various materials can be used, but from the viewpoint of optical characteristics, transparent adhesives such as Optical Clear Adhesive (OCA) and Cemedine are preferable, and manufacturing efficiency is high. In view of the above, an ultraviolet (Ultraviolet, UV) hardening resin binder is also preferred.

As the bonding layer, ethylene vinyl acetate (Ethylene Vinyl) is preferred. Acetate (EVA) resin (ethylene-vinyl acetate copolymer resin) adhesive layer, and the EVA resin adhesive layer is preferably disposed after the reflective film is formed on the surface of the glass plate. The thickness of the EVA resin adhesive layer is preferably 0.5 mm or less, 0.4 mm or less, 0.3 mm or less, 0.2 mm or less, 0.1 mm or less, or 0.05 mm or less, and more preferably 0.005 mm to 0.03 mm. Thereby, high-resolution imaging is easily obtained.

When forming a bonding layer, especially an EVA resin bonding layer, it is preferred to The heating is carried out at a temperature of preferably 50 ° C or higher, 70 ° C or higher, 90 ° C or higher, or 100 ° C or higher, and more preferably 110 ° C to 250 ° C. Thereby, the formation time of the EVA resin layer can be shortened. Further, the pressure during heating is preferably 700 torr or less, 70 torr or less, 10 torr or less, 1 torr or less, or 0.1 torr or less, and more preferably 0.01 torr or less. Thereby, foaming at the interface of the adhesive layer, particularly the EVA resin adhesive layer, can be suppressed.

From the viewpoint of production efficiency, the adhesive layer is preferably formed by coating of a binder. Various methods can be used as the coating method of the binder, but among them, dispenser coating and screen printing are preferred from the viewpoint of coating workability.

As a method of integrating glass sheets with each other, it is also possible to consider A method of performing heat treatment in a state in which the glass plates are overlapped. In this method, since the adhesive layer is not required, it is easy to narrow the interval of the reflective film. Further, as long as the adjacent surfaces are smooth with each other, it is possible to integrate the layers at a low temperature (about 250 ° C).

The optical imaging member of the present invention is an optical body including a pair of glass laminates The image forming member is characterized in that each of the pair of glass laminates is the glass laminate, and the pair of glass laminates are disposed such that the surfaces on which the reflection films are formed are orthogonal to each other.

Preferably, the pair of glass laminates are bonded and fixed by a binder. That is, Jiawei has a bonding layer between the glass laminates. In this way, a pair of glass laminates can be firmly bonded and fixed. Further, in order to minimize the optical influence, the thickness of the adhesive layer is preferably 100 μm or less, 70 μm or less, 50 μm or less, or 40 μm or less, and more preferably 1 μm to 30 μm. Further, as the binder, various materials can be used, but a transparent binder such as OCA is preferable.

Preferably, a glass plate is placed on the outermost layer side of the pair of glass laminates, and it is preferable to bond and fix the glass plate and the glass laminate by a bonding layer. Specifically, it is preferable that the first cover glass plate, the adhesive layer, the first glass laminate, the adhesive layer, the second glass laminate, the adhesive layer, and the second cover glass are laminated in this order. Thus, the surface of a pair of glass laminates (preferably a cut surface) is not required to be polished with high precision, and the manufacturing cost of the optical imaging member can be greatly reduced.

The surface roughness Ra of the surface (preferably the cut surface) of the pair of glass laminates is preferably 0.01 μm or more, 0.05 μm or more, 0.1 μm or more, and 0.2 μm. The upper portion is preferably 0.4 μm or more, more preferably 0.7 μm or more, and is preferably 3 μm or less, 2 μm or less, 1.5 μm or less, or 1.2 μm or less, and particularly preferably 1 μm or less. If the surface roughness Ra of the surface of a pair of glass laminates is to be too small, the necessity of polishing the surface becomes high, and as a result, the manufacturing cost of the optical imaging member may increase. On the other hand, if the surface roughness Ra of the surface of the pair of glass laminates is too large, air is likely to be mixed into the binder layer.

Preferably, the refractive index n _d of the adhesive layer for bonding the fixed glass laminate to the laminated glass sheet matches the refractive index of the glass sheet in the glass laminate. The difference between the refractive index n _d of the glass plate and the adhesive layer is preferably 0.2 or less, 0.15 or less, 0.12 or less, 0.1 or less, 0.08 or less, 0.05 or less, 0.02 or less, 0.01 or less, or 0.008 or less, and particularly preferably 0.005 or less. Thereby, even if the surface of the adhesive layer side of the glass laminate is not polished, the diffusion reflection at the interface between the glass laminate and the adhesive layer can be reduced. As a result, the manufacturing cost of the optical imaging member can be greatly reduced. Further, the refractive index n _d can be measured by a precision refractometer.

Preferably, the refractive index of the bonding layer matches the refractive index of the cover glass. The difference in refractive index n _d between the cover glass plate and the adhesive layer is preferably 0.2 or less, 0.15 or less, 0.12 or less, 0.1 or less, 0.08 or less, 0.05 or less, 0.02 or less, 0.01 or less, or 0.008 or less, and particularly preferably 0.005 or less. Thereby, the diffused reflection at the interface between the cover glass plate and the adhesive layer can be reduced.

The refractive index n _{d of the} adhesive layer is preferably 1.60 or less, 1.55 or less, 1.54 or less, 1.52 or less, or 1.51 or less, more preferably 1.50 or less, further preferably 1.45 or more, or 1.48 or more, and particularly preferably 1.49 or more. Thereby, it is easy to match the refractive index of a glass plate or a cover glass plate, and it can suppress the diffuse reflection of the interface of a bonding layer.

The surface roughness Ra of the cover glass plate is preferably 1.0 nm or less and 0.8 nm. Hereinafter, it is 0.6 nm or less, 0.5 nm or less, 0.4 nm or less, 0.3 nm or less, or 0.2 nm or less, and particularly preferably 0.001 nm to 0.1 nm. In this way, the mechanical strength of the optical imaging member can be improved.

The cover glass plate is preferably formed by an overflow down-draw method. So, overlay The surface accuracy of the glass plate is improved, and the grinding step can be omitted.

The cover glass plate is preferably a reinforced glass having a compressive stress layer on the surface. Glass. In this case, the compressive stress value of the compressive stress layer is preferably 200 MPa or more, 400 MPa or more, or 600 MPa or more, more preferably 800 MPa to 1500 MPa, and the stress depth is preferably 10 μm or more, 20 μm or more, or 30 μm or more, and more preferably 40 μm to 80 μm. In this way, the mechanical strength of the optical imaging member can be improved.

The cover glass plate is preferably on the outer side surface (opposite to the glass laminate) Side) has an anti-reflection film (anti-reflection layer). Thereby, the reflection of the outer surface is suppressed, and high-resolution imaging is easily obtained.

The method for producing a glass laminate of the present invention is characterized by comprising: preparing a step of forming a glass plate with a reflective film on which at least one surface of a glass plate having a thickness of 500 μm or less is formed; and integrating a glass plate with a reflective film to obtain a laminated body of the glass laminate Preferably, the glass sheet with the reflective film is laminated by means of a binder. Here, the technical features of the method for producing a glass laminate according to the present invention (for example, preferred characteristics and morphology of a glass plate or a glass laminate) are partially described in the description column of the glass laminate of the present invention. this In the description, the description of the overlapping portions is omitted for convenience.

In the method for producing a glass laminate according to the present invention, it is preferred to reflect the belt The glass plate of the film is laminated and integrated by the pressing force, and more preferably, the pressure is applied to laminate the pressure between the glass plates with the reflective film interposed therebetween. In this way, the binder is easily spread between the glass sheets with the reflection film, and the adhesion of the binder is improved, so that the integration strength of the glass laminate can be improved.

As the apparatus for imparting a pressing force, it is preferred to use a roller. So it's easy The ground is given pressure.

Preferably, the adhesive is applied to the glass with a reflective film by a dispenser or the like. After the surface of the plate is overlapped with another glass plate with a reflective film on the glass plate, the roller is biased against the glass plate with the reflective film while rotating the roller from one end of the glass plate with the reflective film to the other end. . Thus, the deflection of the glass plate with the reflection film is suppressed, and the adhesion of the binder is improved, so that the integration strength of the glass laminate can be improved.

Preferably, the adhesive is applied to the first reflective film by a dispenser or the like. a surface of the glass plate, and after the glass plate of the second reflective film is superposed on the glass plate, the roller is moved from one end of the glass plate of the second reflective film to the other end, and the second reflective film is The glass plate is given a pressing force, and further, the adhesive is applied to the surface of the second glass plate with the reflective film by a dispenser or the like, and after the third glass plate with the reflective film is superposed on the glass plate, In the opposite direction to the case of the glass plate with the second reflective film, the roller is rotated from one end of the glass plate of the third reflective film to the other end, and the glass plate of the third reflective film is pressed. For the force, it is preferred to repeat the step of sequentially integrating the glass sheets with the reflective film. Thus, the glass laminate can be efficiently produced.

Preferably, the step of applying a pressing force to the glass sheet with a reflecting film is performed before the glass laminated body is cut into strips to appropriately apply a pressing force, and the length dimension and the width dimension of the glass sheet in the step are compared. The optimum is 200mm or more, 300mm or more, 500mm or more, 600mm or more, or 800mm or more, and more preferably 1000mm~3000mm.

The method for producing a glass laminate according to the present invention preferably includes a glass laminate in which a glass sheet with a reflection film is integrated, and is cut into strips in a direction orthogonal to a surface on which the reflective film is formed. step. In this way, the strip-shaped glass laminate can be easily produced, and the manufacturing efficiency of the optical imaging member can be improved.

As a method of cutting a glass laminate into a strip shape, various methods can be used. Among them, it is preferable to use a wire saw for cutting, and it is preferable to cut the wire saw while supplying a slurry containing abrasive grains. Further, it is preferable that the surface of the wire saw with respect to the glass laminate is 45° or less, 30° or less, 20° or less, 10° or less, 5° or less, 3° or less, or 1° or less. The cutting is performed in the state of the angle. The cutting of the glass laminate is different from the cutting of a usual glass monomer, and a composite material having a glass plate, a reflective film, a bonding layer, or the like is cut. Therefore, when the glass laminate is cut, if the bonding strength of each constituent member is insufficient, a part of the constituent member may be peeled off. Therefore, when the above method is used as the cutting method, the stress which causes peeling of various members can be reduced, and the above problem can be appropriately prevented.

The line width of the wire saw is preferably 500 μm or less, 300 μm or less, or 200 μm or less, and more preferably 10 μm to 100 μm. If the line width of the wire saw is too large, the yield of the strip-shaped glass laminate tends to decrease. Furthermore, if the line width of the wire saw is too small, the wire may be broken at the time of cutting.

In the case of cutting using a wire saw, it is preferable to provide a circulation device for slurry to precipitate and recover the metal contained in the cut slurry, and it is more preferable to provide a metal sink groove. Further, if metal is mixed into the slurry, the cutting efficiency is liable to lower.

The method of manufacturing an optical imaging member of the present invention is characterized by comprising the steps of: preparing a pair of glass laminates by integrating a glass sheet with a reflection film; and forming a surface of the reflection film with each other The step of obtaining a pair of glass laminates in an orthogonal manner to obtain an optical imaging member is preferably produced by the method for producing a glass laminate according to the present invention. Here, the technical features of the method for producing an optical imaging member of the present invention (for example, a glass plate, a glass laminate, a preferred property and a form of a method for producing a glass laminate) are partially described in the glass laminate and the glass of the present invention. In the description column of the manufacturing method of the laminated body. In the present specification, the description of the overlapping portions will be omitted for convenience.

Preferably, the method for producing an optical imaging member of the present invention further comprises the step of disposing a glass plate on a laminated outer surface (usually a cut surface) of a pair of glass laminates. Thus, the manufacturing cost of the optical imaging member can be greatly reduced without polishing the laminated outer surface of a pair of glass laminates with high precision. Further, in this case, it is preferable that the outer surface of the laminated layer of the pair of glass laminates is not substantially polished.

Next, the glass laminate of the present invention will be described with reference to the accompanying drawings. An example of a member. Fig. 1 is a conceptual perspective view showing an example of a glass laminate 1 of the present invention. The glass laminate 1 is formed by laminating a glass plate 10 having a thickness of 500 μm or less, and each has a reflection film 11 between the glass plates 10. On one surface of the glass plate 10, a reflective film 11 is formed, and on the other surface, a reflective film 11 is not formed. The glass plates 10 are laminated and integrated by a bonding layer (not shown) such that the reflecting films do not overlap each other. Further, in the figure, the thickness of the reflective film 11 is shown exaggeratedly.

Fig. 2 is a conceptual squint showing an example of the glass laminate 2 of the present invention. In the figure, the glass laminate 1 shown in Fig. 1 is cut into strips in a direction orthogonal to the surface on which the reflective film is formed. In this way, the strip-shaped glass laminate 2 can be efficiently produced. Further, the cutting width can be appropriately determined depending on the size of the optical imaging member.

3 is a conceptual squint showing an example of the optical imaging member 3 of the present invention. Figure. The optical imaging member 3 uses a pair of the glass laminate 2 shown in FIG. 2, and the opposing faces (cut faces) of the glass laminate 2 such that the faces of the pair of glass laminates 2 on which the reflective film 13 is formed are orthogonal to each other. ) They are bonded and fixed by a bonding layer (not shown). The optical imaging member 3 narrows and uniformizes the interval between the reflective films 13 by the glass plate 12.

Fig. 4 is a conceptual perspective view showing an example of the optical imaging member 4 of the present invention. The optical imaging member 4 uses a pair of the glass laminate 2 shown in FIG. 2, and the opposing faces (cut faces) of the glass laminate 2 such that the faces of the pair of glass laminates 2 on which the reflective film 14 is formed are orthogonal to each other. ) They are bonded and fixed by a bonding layer (not shown). The optical imaging member 4 narrows and uniformizes the interval between the reflection films 14 by the glass plate 15. On the outer surface of the laminate of the glass laminate 2, a cover glass plate is disposed 16. The pair of glass laminates 2 and the cover glass plate 16 are bonded and fixed by a bonding layer (not shown). Here, the refractive index of the adhesive layer matches the refractive index of the glass plate 15 and the cover glass plate 16.

Further, an example of a method for producing a glass laminate according to the present invention will be described with reference to the drawings. 5(a), 5(b), and 5(c) are conceptual cross-sectional views showing an example of a method of integrating a glass film with a reflection film. Fig. 5(a) shows a state in which the glass sheet 21 with the reflection film is adsorbed and held by the suction device 22, and sequentially laminated, in the laminated glass laminate 24 by the coating device 23 of the adhesive immediately before the lamination. The outermost surface is coated with a binder. Fig. 5(b) shows a state in which the glass plate 21 with a reflection film is superposed on the laminated glass laminate 24, and the roller 25 is rotated by one end of the glass plate 21 with the reflection film to the other end. The glass plate 21 with a reflection film is pressed to integrate the outermost glass plate 21 with a reflection film and the laminated glass laminate 24. Fig. 5(c) shows a state in which after the glass plate 26 with another reflection film is superposed on the laminated glass laminate 26, the glass plate of the roller 25 is provided with a reflection film in the opposite direction to the previous one. When one end of the 26 is rotated to the other end, a pressing force is applied to the glass plate 26 with a reflection film, and the glass plate 26 with a reflection film is laminated and integrated with the laminated glass laminate 27.

6(a), 6(b), and 6(c) show the large size by a wire saw A conceptual explanatory diagram of an example of a method of cutting a glass laminate into strips. (a) of FIG. 6 is a view showing a state before the wire saw 32 is brought into contact with the large glass laminate 31 so that the large glass laminate 31 is cut in a direction orthogonal to the surface on which the reflective film is formed. In the cross-sectional view, the wire saw 32 is in a state in which the surface of the glass film of the large glass laminate 31 is inclined by a degree. (b) of FIG. 6 is a conceptual view showing a state in which the large-sized glass laminate 31 is cut in a direction orthogonal to the surface on which the reflective film is formed. Here, the angle of the wire saw 32 is maintained in a state of being inclined by a degree from the surface of the glass plate of the large glass laminate 31. (c) of FIG. 6 is a conceptual perspective view showing a state in which the large glass laminated body 31 is cut in a direction orthogonal to the surface on which the reflecting film is formed, and is divided into strip-shaped glass laminated bodies 33.

The glass plate of the present invention is characterized in that the thickness is 500 μm or less, and At least one surface is formed with a reflective film. Further, the glass plate of the present invention is characterized in that the thickness is 500 μm or less, and the transmittance at a wavelength of 350 nm is 70% or more in terms of a thickness of 500 μm, and the glass plate is used for a glass laminate. Further, the technical features of the glass plate of the present invention are as described above, and a detailed description thereof will be omitted.

[Example 1]

The invention will be described in detail based on the examples. However, the following examples are merely illustrative. The present invention is not limited by the following examples.

Table 1 shows the glass composition and characteristics of the glass film (sample No. 1 to sample No. 7).

First, the glass raw material is blended so as to have the glass composition described in Table 1, and the obtained glass raw material is supplied to a glass melting furnace and melted at 1500 ° C to 1600 ° C. Then, the obtained molten glass was formed into a thickness of the surface and a length of 1500 mm by an overflow down-draw method. Then, the newly formed glass sheet is moved to a slow cooling area. At this time, at 10 ¹² dPa. s~10 ¹⁴ dPa. The cooling rate in the s temperature was 20 ° C / min, and the temperature in the slow cooling zone and the glass drawing speed were adjusted.

The density is a value measured by the well-known Archimedes method.

The strain point is a value determined based on the method of ASTM C336-71.

The glass transition temperature is a value measured based on the thermal expansion curve and based on the method of JIS R3103-3.

The softening point is a value determined based on the method of ASTM C338-93.

10 ^4.0 dPa. s, 10 ^3.0 dPa. s, 10 ^2.5 dPa. The temperature at s is a value measured by a platinum ball pulling method. The lower the temperature, the more excellent the meltability.

The Young's modulus is a value measured by a resonance method.

The coefficient of thermal expansion is a value obtained by measuring an average coefficient of thermal expansion at 30 ° C to 380 ° C using a dilatometer. As a sample for measuring the thermal expansion coefficient, a cylindrical sample having a diameter of 5 mm × 20 mm which was chamfered on the end surface was used.

The liquidus temperature is a value as follows: a glass powder which passed through a standard sieve of 30 mesh (500 μm) and remained at 50 mesh (300 μm) was placed in a platinum boat and kept in a temperature gradient furnace for 24 hours to precipitate crystals. The measured temperature is measured. The liquidus viscosity is a value obtained by measuring the viscosity of the glass at the liquidus temperature by a platinum ball pulling method.

The HCl resistance and the BHF resistance were evaluated by the following methods. First, after optical polishing of both surfaces of each sample, a part of the surface is masked. Then, the chemical solution prepared to a predetermined concentration is immersed at a predetermined temperature for a predetermined period of time. Subsequently, the mask was removed, and the surface roughness meter was used to measure the step difference between the mask portion and the eroded portion, and this value was taken as the amount of erosion. Further, after optical polishing of both surfaces of each sample, the chemical solution prepared to a predetermined concentration is immersed at a predetermined temperature for a predetermined period of time. Subsequently, the surface of the sample was visually observed, and the case where the surface became cloudy or cracked or cracked was evaluated as "x", and the case where no change was observed was evaluated as "○". In addition, at this time, there was an unmeasured sample, and only "○" was evaluated.

Here, the amount of erosion resistance to BHF was measured using a 130 BHF solution (NH ₄ HF: 4.6 mass%, NH ₄ F: 36 mass%) under the treatment conditions of 20 ° C for 30 minutes. The appearance evaluation was carried out using a 63 BHF solution (HF: 6% by mass, NH ₄ F: 30% by mass) under the treatment conditions of 20 ° C for 30 minutes. Further, the amount of erosion resistance to HCl was measured by using a 10% by mass aqueous hydrochloric acid solution at 80 ° C for 24 hours. The appearance evaluation was carried out using a 10% by mass aqueous hydrochloric acid solution at 80 ° C for 3 hours.

The crack generation rate was in a constant temperature and humidity chamber maintained at a humidity of 30% and a temperature of 25 ° C, and a Vickers indenter set to a load of 1000 g was pressed into the surface of the sample (optical polishing surface) for 15 seconds, in the 15 seconds. The number of cracks generated from the four corners of the indentation is counted (up to four cracks per one indentation). The indenter was pressed 20 times and evaluated in terms of total crack generation number / 80 × 100.

The surface roughness Ra of the surface is based on the square according to JIS B0601:2001. The value measured by the law.

The surface roughness Ra of the end surface is a value measured by a method according to JIS B0601:2001.

The undulation refers to a value obtained by measuring a WCA (filter center line undulation) described in JIS B0601:2001 using a stylus type surface shape measuring device, which is based on SEMI STD D15. -1296 "Measurement method of surface undulation of FPD glass substrate" was measured, and the cut at the time of measurement was 0.8 mm - 8 mm, and it measured on the length of 300 mm in the perpendicular direction with respect to the drawing direction of the glass plate.

The difference between the maximum thickness and the minimum thickness of the glass plate is a value as follows, that is, using a laser thickness measuring device, the laser is scanned from either side of the glass plate in the thickness direction, thereby determining the maximum of the glass plate. The thickness and minimum thickness, and the value obtained by subtracting the value of the minimum thickness from the value of the maximum thickness.

The refractive index n _d is a value measured using a precision refractometer (KPR-2000, manufactured by Shimadzu Corporation).

As is clear from Table 1, the samples No. 1 to No. 7 had small thicknesses and good surface precision. Therefore, if a reflective film is formed on the surface of sample No. 1 to sample No. 7, and then the sample layer is integrated, a glass laminate can be produced without causing an increase in cost. Further, by arranging a pair of glass laminates so that the surfaces on which the reflection films are formed are orthogonal to each other, an optical imaging member capable of high-resolution imaging can be obtained.

For sample No. 1 to sample No. 6, the transmittance was measured at the thickness and wavelength in the table. As the measuring device, use UV-3100PC at the slit width: 2.0 nm, scanning speed: medium speed, sampling pitch: 0.5 nm. The results are shown in Table 2.

It can be clarified from Table 2 that no matter what thickness is in sample No. 1 to sample No. 6 At both the wavelength and the wavelength, the transmittance is high.

Further, the haze was measured by a haze meter (haze meter NDH-5000 manufactured by Nippon Denshi Kogyo Co., Ltd.) for each sample. The results are shown in Table 2. As is clear from Table 2, since the haze of the sample No. 1 to the sample No. 6 was small, the diffusion reflection on the surface was suppressed.

[Embodiment 2]

First, a glass plate (glass film) having a glass composition of sample No. 2 was prepared. The glass film had a thickness of 0.25 mm and a refractive index n _d of 1.50. Then, on one surface of the glass film, an Al film or a SiO ₂ film was sequentially formed, and then 1600 pieces of the obtained glass film layer were integrated by using LOCTITE 454 (manufactured by Henkel Japan Co., Ltd.). A glass laminate is obtained. Then, using a multiwire saw (abrasive grain #600), the glass laminate is cut in a direction orthogonal to the surface on which the reflective film is formed, that is, in the thickness direction of the glass film, and then washed to remove abrasive grains or the like. A glass laminate (400 mm × 400 mm × 0.75 mm) was obtained. Further, at the time of cutting, the angle of the wire saw was adjusted to be parallel to the surface of the glass film of the glass laminate. When the surface roughness of the cut surface of the glass laminate was measured, Ra was 0.7 μm, Rq was 0.89 μm, and Rsm was 63 μm. Furthermore, UV-curable resin (Loctite 3301 manufactured by Henkel Japan Co., Ltd.) was added dropwise to the cut surface of the glass laminate, and then another glass laminate was placed so that the surfaces on which the reflective film was formed were orthogonal to each other, and 365 nm UV was used from above. A lamp (30 mW/cm ² ) was irradiated for 100 seconds to bond and fix a pair of glass laminates. Further, two sheets of glass sheets having a glass composition of sample No. 2 were prepared. The cover glass plate has a thickness of 0.3 mm and is formed by an overflow down-draw method. Finally, a glass plate is placed on the outermost layer side of the pair of glass laminates, and the optical image forming member is obtained by bonding and fixing the same UV curing resin as described above.

1‧‧‧glass laminate

10‧‧‧ glass film

11‧‧‧Reflective film

Claims (26)

A glass laminate in which a glass laminate having a thickness of 500 μm or less is laminated, and a reflective film is provided between the glass sheets. The glass laminate according to claim 1, wherein a laminated glass plate is laminated. The glass laminate according to claim 1 or 2, wherein a glass plate having a reflective film formed on at least one surface thereof is laminated. The glass laminate according to any one of claims 1 to 3, wherein the surface of the glass plate has an average surface roughness Ra of 100 Å or less. The glass laminate according to any one of claims 1 to 4, wherein the glass sheet has an undulation of 1 μm or less. The glass laminate according to any one of claims 1 to 5, wherein a difference between a maximum thickness and a minimum thickness of the glass sheet is 20 μm or less. The glass laminate according to any one of claims 1 to 6, wherein the glass plate has an unpolished surface. The glass laminate according to any one of claims 1 to 7, wherein the glass sheet has a length dimension of 500 mm or more. The glass laminate according to any one of claims 1 to 8, wherein the glass sheet is formed by an overflow down-draw method. The glass laminate according to any one of the preceding claims, wherein the glass sheet has a bonding layer, and the thickness of the bonding layer is 100 μm. the following. The glass laminate according to any one of claims 1 to 10, wherein the reflective film is Al or Ag. An optical imaging member, comprising: a pair of glass laminates, wherein the pair of glass laminates are respectively the glass laminate according to any one of claims 1 to 11, and the pair of glasses The laminated body is disposed such that the surfaces on which the reflective film is formed are orthogonal to each other. The optical imaging member according to claim 12, wherein a laminated glass plate is disposed on an outer surface of the laminated layer of the pair of glass laminates. The optical imaging member according to claim 13, wherein an antireflection film is formed on an outer surface of the cover glass plate. A method for producing a glass laminate, comprising: a step of preparing a glass plate with a reflection film, wherein the glass plate with a reflection film is formed with a reflection film on at least one surface of a glass plate having a thickness of 500 μm or less; The glass sheet with a reflective film is laminated to obtain the above-mentioned glass laminate. The method for producing a glass laminate according to claim 15, wherein the glass sheet with the reflection film is laminated by a binder. The method for producing a glass laminate according to the above aspect of the invention, wherein the glass sheet with a reflection film is laminated and integrated under pressure. A method for producing a glass laminate, comprising: forming a glass laminate in which a glass sheet with a reflection film is integrated, and cutting the strip in a direction orthogonal to a surface on which the reflective film is formed; A step of. The method for producing a glass laminate according to claim 18, wherein the glass laminate is cut by a wire saw. The method for producing a glass laminate according to the above aspect of the invention, wherein the surface of the glass sheet of the glass laminate is limited to an angle of 45 or less with respect to the surface of the glass sheet. , cut off. A method of manufacturing an optical imaging member, comprising: a step of preparing a pair of glass laminates by integrating a glass sheet with a reflection film; and forming a surface of the reflection film with each other The above-described pair of glass laminates are arranged in an orthogonal manner to obtain the above-described optical imaging member. The method of producing an optical imaging member according to claim 21, wherein the pair of glass laminates are strip-shaped. The method for producing an optical imaging member according to claim 21, further comprising the step of disposing a glass plate on the outer surface of the laminated layer of the pair of glass laminates. A method of manufacturing an optical imaging member, comprising: forming a reflective film on at least one surface of a glass plate having a thickness of 500 μm or less, thereby obtaining a glass plate with a reflective film; a step of integrating the glass sheets with a reflection film to obtain a glass laminate; and arranging the pair of glass laminates so that the surfaces on which the reflection films are formed are orthogonal to each other, thereby obtaining the optical imaging member. step. A glass plate characterized by having a thickness of 500 μm or less; and a reflective film formed on at least one surface. A glass plate characterized by having a thickness of 500 μm or less and a transmittance of 70% or more at a wavelength of 500 μm in terms of a thickness of 500 μm; and the above glass plate is used for a glass laminate.