JPH07281165A - Method for sticking plane substrate and production of flat plate type lens array - Google Patents

Abstract

PURPOSE:To provide a method for sticking a plane substrate and a thin plane sheet glass substrate to each other without generating microwaving. CONSTITUTION:This method comprises supplying adhesive resin to one surface of the plane substrate 11 and/or the thin plane sheet glass 1, mating and arranging the substrate 11 and the thin plane sheet glass substrate 12, pressurizing these substrates by pressurizing means 31, 32 to develop the resin 21 held therebetween, then curing the resin, thereby sticking the substrate 11 and the thin plane sheet glass substrate 12 to each other. The development of the resin 21 is executed by pressurizing the substrates via a flat pressurizing surface plate. The curing and sticking of the resin 21 are thereafter executed in the state of completely removing the pressurization. The sticking of the substrates is executed by directly using a static pressure or executing pressurization via a high-polymer elastic material in such a manner that uniform pressurization is executed between at least the substrate 11 and the pressurizing means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for laminating a flat substrate and a flat thin glass substrate with an adhesive resin, and more particularly to a flat microlens array for forming a liquid crystal display device and a liquid crystal using the same. When making a display element,
The present invention relates to an effective method for laminating flat substrates.

[0002]

2. Description of the Related Art Conventionally, a method of attaching flat substrates to each other with an adhesive resin, particularly when one of the flat substrates is a thin plate, dropping the adhesive resin on the surface of the flat substrate,
After placing another thin plate on it, press it on a flat press table such as a mirror-polished glass plate, and irradiate light or heat it in the state of close contact pressure to cure the resin. The common method is to bond them.

[0003]

Consider the case where, in the above-mentioned bonding method, at least one of the flat substrates to be bonded is flat thin glass having a plate thickness of 0.5 mm or less. When the pressure platen is pressed and adhered,
The flat thin glass reflects the flatness of the pressure platen, which causes minute waviness. The pressure platen is often finished by polishing, and its flatness depends on the precision of polishing, but it is generally finished to about 10 μm in consideration of cost. Is. This precision is usually sufficient.

When the resin is spread between the flat thin glass sheet and the flat substrate, the minute undulations are directly projected on the resin side surface of the flat thin glass sheet. Therefore, the thickness of the developed resin varies delicately, and the resin is cured in that state. Therefore, the present inventors have found that the variation in the thickness of the resin is reflected as it is on the flat thin glass substrate, and a microwaviness is generated on the surface of the thin glass substrate. Needless to say, the above-mentioned phenomenon has a greater influence as the plate thickness of the flat thin glass substrate to be bonded becomes thinner.

For example, when a flat glass substrate having a thickness of 0.5 mm and a flat thin glass substrate having a thickness of 0.2 mm are bonded by the above method, the amplitude is 2 to 4 μm.
Micro waviness with a m of 10 to 25 mm occurs. Figure 7
See. Such minute waviness does not pose a particular problem in normal use.

However, the above-mentioned flat substrate is a quartz glass substrate having a plurality of array-shaped recesses, and has the function of a flat plate type microlens which becomes a convex lens by filling the recesses with resin or the like. When it is bonded to a flat thin glass substrate and this bonded substrate is used as a substrate for a liquid crystal display element, minute waviness on the substrate surface deteriorates the display quality. This is 2 to 4 μm
This is because the amplitude of is a value that cannot be ignored as compared with the thickness of the liquid crystal layer of 3 to 5 μm.

Therefore, it is an object of the present invention to provide a method for bonding a flat substrate and a flat thin glass substrate without causing microwaviness.

[0008]

In order to solve the above-mentioned problems, in the present invention, after the resin is pressure-developed between the two substrates, the resin is cured and cured while the pressure is completely removed. Stick together.

Further, the thin glass substrate side is hydrostatically pressed directly or through a polymeric elastic body to develop the resin, and the resin is further cured in the pressed state for bonding.

First, examples of the flat substrate that can be used in the present invention include substrates made of materials such as glass, ceramics, metals and resins. In particular, when manufacturing a liquid crystal display element, a glass substrate is used as a flat substrate. Examples of the glass substrate include soda lime glass, alkali aluminosilicate glass, alkali borosilicate glass, non-alkali glass, crystallized glass and quartz glass. The plate thickness is not particularly limited and may be a substrate having a large rigidity of the plate itself or a thin glass substrate having a small rigidity of the plate itself.

On the other hand, as the flat thin glass substrate, the above-mentioned glass substrate can be used. In addition, the plate thickness of the flat thin glass that effectively exhibits the effect of the present invention varies depending on the rigidity of the glass substrate used, but in general, the plate thickness is 0.5 mm or less. The effect is remarkable when the thickness is 0.2 mm or less.

The flat thin glass substrate has a thickness of 0.5 mm.
In the case of exceeding 0.7 mm and more than 0.7 mm, since the plate itself has a large rigidity, when the pressure platen is pressed and brought into close contact with the platen, minute undulations depending on the flatness of the pressure platen are unlikely to occur, and therefore the plate is developed. The variation in resin thickness is reduced, and minute waviness is less likely to occur on the surfaces of the bonded substrates.

As the adhesive resin used in the present invention, polyester resin, epoxy resin, silicone resin, phosphazene resin, phenol resin, polyimide resin, or any other photocurable and thermosetting resin can be used. . Among them, polyester resin, epoxy resin,
A photocurable resin such as a silicone resin is preferable in terms of productivity because it cures in a short time.

From the characteristics of the viscosity of the resin used, 0.1
A wide range of viscosity from Poise to about 100 Poise can be used. When the viscosity of the resin is low, variations in the resin layer thickness are unlikely to occur, but on the other hand, it is difficult to increase the resin layer thickness. On the other hand, when the viscosity of the resin is high, it is possible to increase the thickness of the resin layer, but on the other hand, variations in the thickness of the resin layer tend to occur. 1 in actual work
A resin having a viscosity of about poise to about 50 poise is preferable.

Further, by filling a glass substrate having a plurality of substantially spherical array-shaped concave portions arranged two-dimensionally on its surface and the concave portions of the array with a transparent resin having a refractive index higher than that of the glass substrate, A flat plate microlens array that is a convex lens is formed. Further, consider a case where the quartz substrate of the liquid crystal display device and the flat plate microlens array are bonded together. In this case, the transparent resin used must have a refractive index higher than that of the glass substrate.
Currently, such resins are available only if they have a high viscosity to some extent. Therefore, as described above, variations in the resin layer thickness occur, and minute waviness on the substrate surface deteriorates display quality.

Next, in the method in which the hydrostatic pressure is directly applied, as the hydrostatic pressure, it is possible to use air or nitrogen, helium or the like gas or atoms of a gas at room temperature and a mixture thereof. It is also possible to use liquids such as water and oil.

Further, when pressure is applied through the elastic polymer, the elastic polymer may be rubber such as natural rubber, butadiene rubber, silicon rubber, fluororubber, or polycarbonate, polymethylmethacrylate, polyvinyl chloride. Plastics such as polyethylene can be used.

In general, when the amount of warpage of the flat thin glass sheet to be bonded is small, the method of completely removing the pressure after the resin development is most effective in reducing the microwaviness of the substrate surface. However, if the warpage of the substrate is large and the substrates are separated from the adhesive resin when the pressure is removed, hydrostatic pressure or pressure via a polymer elastic body is used to apply pressure. The method of curing with is effective for preventing the peeling of the substrate before the resin is cured.

[0019]

According to the present invention, when the resin is cured and the substrates are bonded together in the state where the pressure is completely removed after the development of the resin, the resin thickness between the flat substrate and the flat thin glass is not varied. Therefore, the micro-waviness due to the variation in the resin thickness does not occur on the substrates after bonding.

When hydrostatic pressure is applied directly to the resin development, the resin is in a pressurized state, but since it is pressed extremely uniformly, there is no variation in resin thickness, and therefore, after bonding, The substrate does not have minute waviness due to variations in resin thickness. Further, even when pressure is applied to the resin development through the elastic polymer, since the pressure is uniformly applied, there is no variation in the resin thickness, and therefore the variation in the resin thickness on the substrate after bonding is caused. The micro waviness does not occur.

Further, in the case where the obtained bonded substrate is provided with the function of a flat plate type microlens and is used as a counter substrate for a liquid crystal display element, variations in the thickness of the liquid crystal layer can be reduced, so that Color unevenness and the like due to minute waviness are not generated, and display quality is not deteriorated.

[0022]

First, the outline steps of the present invention will be described for each method. (Method of Bonding in Depressurized State) FIG. 1 shows an outline of a bonding process of flat thin glass sheets under the condition that the pressure according to the present invention is completely removed. (1) First, the flat substrate 11 is attached to the lower pressure platen 3 of the pressure device.
1, and the adhesive resin 21 is dropped on the flat substrate 11. (2) Next, in order to prevent air bubbles from entering the flat thin glass sheet 12, the adhesive resin 21 is applied from the central portion of the flat thin glass sheet 12.
To join. (3) Then, the flat substrate 11 and the flat thin glass sheet 1 are gently placed.
The two are bonded by the adhesive resin 21, and this is pressed by the upper pressing platen 32. (4) Furthermore, the pressure-sensitive adhesive resin 21 causes the planar substrate 1 to be pressed.
1 and the flat thin glass plate 12 are spread uniformly, the pressure applied by the upper pressing platen 32 of the pressing device is removed, and the flat thin plate glass substrate 10 is bonded on the lower pressing platen 31.
Then, the adhesive resin is cured by irradiating ultraviolet rays with an ultraviolet ray irradiating device incorporated in the pressure device, or by performing heat treatment with a heating device (not shown) also incorporated in the pressure device. .

The ultraviolet irradiation device is preferably incorporated in either the upper pressure platen or the lower pressure platen of the pressure device, or both. Further, in the above-mentioned method, the resin was cured on the pressure platen, but it is not always necessary, and in the case of curing the resin by heating, it may be cured by heating in another heating furnace or the like. Good.

(Method of Bonding under Pressurization by Hydrostatic Pressure) FIG. 2 shows an outline of a bonding process of flat thin glass sheets using the hydrostatic pressure of the fluid of the present invention for pressurization. (1) First, the flat substrate 11 is placed on the lower pressure platen 31, and the adhesive resin 21 is dropped on the flat substrate 11. (2) Next, the flat thin glass sheet 12 is bonded to the adhesive resin 21 from the center of the flat thin glass sheet 12 so that air bubbles do not enter. (3) Subsequently, the hydrostatic device 40 is lowered to this, and a fluid 42 (for example, gas) is introduced from the outside to pressurize the hydrostatic pressure device 40, so that the hydrostatic pressure exists in the space between the hydrostatic container 41 and the O-ring 43. It directly acts on the substrate 12 held via the. (4) Further, after the adhesive resin 21 is uniformly spread between the flat substrate 11 and the flat thin glass sheet 12 by the above-mentioned pressurization, the flat thin glass sheets bonded together under the condition that hydrostatic pressure is applied. The adhesive resin is cured by irradiating the substrate 10 with ultraviolet rays or performing heat treatment.

When both substrates to be bonded are thin glass substrates, it is necessary to apply a uniform pressure to both substrates. In such a case, it is difficult to use the hydrostatic pressure on both substrate surfaces as the pressing means. It is extremely difficult to balance the pressurization state on both substrate surfaces, and although micro waviness does not occur, it is considered that the entire substrate warps. Therefore, when both substrates are thin glass substrates as described above, it is preferable that at least one of the pressurizing means uses pressurization by a polymer elastic body described later.

The example of the apparatus shown in FIG. 2 is suitable when a gas is used as the fluid. On the other hand, when a liquid is used as the fluid, the device shown in FIG. 3 is suitable. (1) First, the hydrostatic pressure device 4 provided below the pressurizing device.
The flat thin glass substrate 12 is placed at 0, and the adhesive resin 21 is dropped on the flat glass substrate 12. (2) Next, the flat substrate 11 is bonded to the adhesive resin 21 from the center of the flat substrate 11 so that air bubbles do not enter. (3) Further, the upper pressure platen 32 is lowered, and the flat thin glass substrate 12 is added to the fluid 42 (liquid) in the hydrostatic container 41 via the piston 45 provided in the lower pressure platen 31. Press. (4) Further, the adhesive resin 21 is uniformly spread between the flat substrate 11 and the flat thin glass sheet 12 by the above-mentioned pressurization, and then the flat thin glass sheets bonded together under the condition that hydrostatic pressure is applied. The adhesive resin is cured by irradiating the substrate 10 with ultraviolet rays or performing heat treatment. In this case, if the flat substrate 11 is also transparent, a photocurable resin can be used.

(Method of Bonding under Pressure with Polymer Elastic Material) FIG. 4 shows an outline of a bonding process of flat thin glass sheets using the pressure by the polymer elastic material of the present invention. (1) First, the flat substrate 11 is placed on the lower pressure platen 41, and the adhesive resin 21 is dropped on the flat substrate 11. (2) Next, the flat thin glass sheet 12 is bonded to the adhesive resin 21 from the center of the flat thin glass sheet 12 so that air bubbles do not enter. (3) Subsequently, this is applied to the polymer elastic body 5 having a flat surface.
The pressure is applied by the upper pressure platen 42 having the number 1. (4) Furthermore, the pressure-sensitive adhesive resin 21 causes the planar substrate 1 to be pressed.
1 and the flat thin glass sheet 12 are uniformly spread, and then the flat thin glass substrate 10 bonded to the flat thin glass substrate 10 is irradiated with ultraviolet rays or subjected to heat treatment in a state where pressure is applied by an elastic body, so that the adhesive resin Cure.

In this case, if the flat substrate 11 is also transparent, a photocurable resin can be used. When both substrates to be bonded are thin plates, a polymeric elastic body may be provided on both the upper and lower pressing plates.

In the above description, the substrate 11 is not particularly limited to a flat substrate, but the bonded substrate according to the present invention is provided with the function of a flat plate type microlens and is used as a counter substrate for a liquid crystal display element or the like. In this case, the substrate 11 is preferably a low expansion glass substrate such as quartz glass. Further, as described above, the bonding method according to the present invention is effective even when the flat substrate has minute irregularities.

Specific examples will be described below. (Example 1) A specific example of a method of bonding in a depressurized state will be described. First, a quartz glass substrate (outer diameter 125 mm, plate thickness 0.
5 ± 0.01 mm) was used as a flat substrate, and the flat substrate was placed on a surface-polished glass lower pressing platen. Next, 0.5 ml of the epoxy photocurable resin (viscosity 1400 cP) was dropped from the cylinder. Subsequently, a quartz glass substrate (outer diameter 12
5 mm and a plate thickness of 0.2 mm ± 0.01 mm) was used as a flat thin plate substrate and was bonded to the photo-curable resin from the center so as to prevent air bubbles from entering. This was pressed at a pressure of 5 kgf / cm ² by means of a surface-polished glass upper part pressure table. In addition, this pressurizer is manufactured by Nikka Engineering Co., Ltd. 2
A P molding machine was used.

As a result, the photo-curable resin sandwiched between the two quartz substrates was spread on the substrate surface having an outer diameter of 125 mm. After the resin was developed, the pressurization by the glass upper part pressure table was stopped, the pressure was completely removed, and then the ultraviolet irradiation was performed. The ultraviolet irradiation conditions were 53 mW / cm ² and 150 seconds. The resin thickness after curing was about 38 μm. Under the curing conditions of this time, the Shore D hardness of the photocurable resin was about 87, and the adhesive strength to the glass substrate was about 80 kgf / cm ² .

The surface unevenness of the thin laminated substrate obtained in the above-mentioned Example 1 was measured by a stylus type roughness meter (Tokyo Seimitsu: Surfcom model number 1500A) with a vertical magnification of 2000 times, a horizontal magnification of 1 time, and a scanning distance. It was measured at 120 mm. The result is shown in FIG. From the profile shown in the figure, it can be seen that the generation of microwaviness due to bonding is not observed at all.

(Embodiment 2) A specific example of a method for laminating under a hydrostatic pressure is shown. First, a quartz glass substrate (outer diameter 125 mm, plate thickness 0.7 ± 0.01 mm) was used as a flat substrate and placed on a surface-polished glass lower pressing platen. Next, an epoxy photocurable resin (viscosity 14
(00 cP) 0.5 ml was dripped from the cylinder. Subsequently, a quartz glass substrate (outer diameter 125 mm, plate thickness 0.2 mm
± 0.01 mm) was used as a flat thin plate substrate and was bonded to a photo-curable resin from the center so as to prevent air bubbles from entering, and this was pressed at a hydrostatic pressure of 0.2 kgf / cm ² using a pressure device.

As a result, the photo-curable resin sandwiched between the two quartz substrates was spread within the substrate surface having an outer diameter of 125 mm. After the resin was developed, it was irradiated with ultraviolet rays under a hydrostatic pressure. UV irradiation conditions are 53mW
/ Cm ² and 150 seconds. The resin thickness after curing is about 4
It was 0 μm. Under the curing conditions of this time, the Shore D hardness of the photocurable resin was about 87, and the adhesive strength to the glass substrate was about 80 kgf / cm ² .

The surface irregularities of the laminated thin substrate obtained in Example 2 were measured with a stylus roughness meter. The measurement conditions are the same as in Example 1. As a result, the same result as the profile shown in FIG. 5 was obtained, and the generation of microwaviness due to bonding was not observed at all.

(Embodiment 3) A specific example of a method of laminating a polymer elastic body under pressure will be described. First, a quartz glass substrate (outer diameter 125 mm, plate thickness 0.5 ± 0.01 mm) was used as a flat substrate and set on a surface-polished glass lower pressing platen. Next, 0.5 ml of the epoxy photocurable resin (viscosity 1400 cP) was dropped from the cylinder. Subsequently, a quartz glass substrate (outer diameter 125 mm, plate thickness 0.2 m
(m ± 0.01 mm) As a flat thin plate substrate, it is bonded to a photo-curable resin from the center so that air bubbles do not enter, and this is pressed through a silicon rubber having a thickness of 5 mm with an upper pressure platen at a pressure of 10 kgf / cm ^2. Pressurized with.

As a result, the photocurable resin sandwiched between the two quartz substrates was spread on the substrate surface having an outer diameter of 125 mm. After the development of the resin, ultraviolet irradiation was carried out under pressure. The ultraviolet irradiation conditions are 53 mW / cm ²
At 150 seconds. The resin thickness after curing was about 24 μm. Under the curing conditions of this time, the Shore D hardness of the photocurable resin was about 87, and the adhesive strength to the glass substrate was about 80 kgf / cm ² .

The surface irregularities of the laminated thin substrate obtained in Example 3 were measured with a stylus roughness meter. The measurement conditions are the same as in Example 1. As a result, the same result as the profile shown in FIG. 5 was obtained, and the generation of microwaviness due to bonding was not observed at all.

(Embodiment 4) An example of a method for manufacturing a flat lens array using the method of bonding in the depressurized state shown in Embodiment 1 will be described. First, as a hydrofluoric acid-resistant protective film on the surface of the quartz glass substrate by the sputtering method,
A Cr film was formed. Next, by photolithography in which a photoresist is applied, exposed, and developed, Cr
Small openings were formed in the film with a predetermined lens array pattern. The formed small aperture array is a hexagonal lattice array, whereby a honeycomb lens array is obtained. It is desirable that the diameter of the small opening is sufficiently smaller than the diameter of the lens to be finally obtained.

The Cr film-coated substrate having the small openings was immersed in an etchant containing hydrofluoric acid (HF) and sodium dodecylbenzenesulfonate (DBS) as a surfactant to carry out chemical etching. Here, the concentrations of hydrofluoric acid and sodium dodecylbenzene sulfonate are
It was set to 10% by weight and 0.1% by weight, respectively. As a result, the surface of the quartz glass substrate is isotropically etched starting from the small opening of the Cr film, and a concave portion that is substantially a part of a sphere is obtained. This first-stage etching is stopped while leaving a flat boundary portion having a slight width between the adjacent concave portions.

Then, after removing the Cr film from the surface of the quartz glass substrate, it was immersed again in the above etchant to etch the entire surface of the substrate. By this two-step etching,
Etching progressed in the peripheral portion of the recess, and the boundary between adjacent recesses became a ridgeline with a sharp upper end. That is, in a plan view, each has the same hexagonal shape, and the adjacent recesses are in a close-packed arrangement in which the adjacent recesses are in close contact with each other.

The above-mentioned quartz glass substrate was placed on a glass lower pressure platen whose surface was polished. Next, 0.5 ml of the epoxy photocurable resin (viscosity 1400 cP) was dropped from the cylinder. Subsequently, a quartz glass substrate (outer diameter 12
5 mm and a plate thickness of 0.2 mm ± 0.01 mm) was used as a flat thin plate substrate and was bonded to the photo-curable resin from the center so as to prevent air bubbles from entering. This was pressed at a pressure of 5 kgf / cm ² by means of a surface-polished glass upper part pressure table.

As a result, the photocurable resin sandwiched between the two quartz substrates was spread on the substrate surface having an outer diameter of 125 mm. After the resin was developed, the pressurization by the glass upper part pressure table was stopped, the pressure was completely removed, and then the ultraviolet irradiation was performed. The ultraviolet irradiation conditions were 53 mW / cm ² and 150 seconds. The resin thickness after curing was about 38 μm.

The surface roughness of the thin-plate laminated substrate having the microlens function obtained in Example 4 was measured with a stylus roughness meter. The measurement conditions are the same as in Example 1. As a result, even when a flat substrate having concavities and convexities on its surface was attached, the same result as the profile shown in FIG. 5 was obtained, and the generation of microwaviness due to the attachment was not observed at all.

The radius of curvature of the convex portion of the lens of the microlens array manufactured this time is 24.3 μm, the refractive index of quartz glass is 1.46, and the refractive index of the filled epoxy resin is 1.595. It was A He-Ne laser was used to irradiate parallel rays and the focal length of this lens was measured and found to be 180 μm (in air). Furthermore, the spot diameter near the focal position is 5.
It was 3 μm, and it was found that it had an excellent light-condensing property of about the diffraction limit.

Further, a liquid crystal display device can be constructed by using the obtained laminated thin substrate having a microlens function. First, a black matrix (light-shielding layer) and a transparent counter electrode were formed on the bonded substrate by a sputtering method, and a liquid crystal display element as a counter substrate of the liquid crystal display element was prototyped and its optical characteristics were evaluated.

As a result, by using this thin-plate laminated substrate having a microlens function, the brightness of the liquid crystal display element does not use the substrate even when the spread angle of incident white light is ± 6 degrees. It was found to be 2.8 times brighter than that of the case. Further, in this liquid crystal display element, since the liquid crystal layer is sandwiched between the substrate having no minute waviness and the quartz glass substrate for TFT, the variation in the thickness of the liquid crystal layer is suppressed as much as possible. Therefore, no display color unevenness was observed.

In the above example of Example 4, the recess was formed in the quartz glass substrate by the etching method, but the recess is also formed by the method of supplying the sol-gel solution onto the substrate and transferring the stamper shape to the same. be able to.

Although the substrate having the microlens function is formed by the above-described etching method in the example of the fourth embodiment, it may be a substrate having the microlens function using the ion diffusion method. In this case, since the substrate often has a warp due to ion diffusion,
The above method of curing the resin in the depressurized state cannot be used. Therefore, it is preferable to use the method of applying pressure through the elastic polymer as shown in Example 3.

(Comparative Example 1) As a comparative example, an example of curing and bonding under pressure will be shown. First, a quartz glass substrate (outer diameter 125 mm, plate thickness 0.5 ± 0.01 mm) was placed on a surface-polished glass lower pressure platen. next,
Epoxy photocurable resin (viscosity 1400 cP) 0.5 m
1 was dropped from the cylinder. Subsequently, quartz glass substrate (outer diameter 125 mm, plate thickness 0.2 mm ± 0.01 mm)
Was bonded to the photo-curable resin from the center so that air bubbles did not enter, and this was pressed at a pressure of 5 kgf / cm ² by a surface-polished glass upper part pressure table.

As a result, the photocurable resin sandwiched between the two quartz substrates was spread on the substrate surface having an outer diameter of 125 mm. The resin was cured by ultraviolet irradiation while being pressed by the upper press plate made of glass. The ultraviolet irradiation conditions were 53 mW / cm ² and 150 seconds.

The surface roughness of the laminated thin substrate obtained in Comparative Example 1 was measured with a stylus roughness meter. The measurement conditions are the same as in Example 1. As a result, as shown in FIG. 7, it was observed that minute undulations having a short period with an amplitude of 2 μm and a period of about 10 mm were generated. This short cycle of micro waviness
This reflects variations in resin thickness between substrates.

[0053]

According to the present invention, when the resin is photo-cured and the substrates are bonded together after the pressure is completely removed after the resin is developed, the pressure is applied to the upper pressure platen and the lower pressure platen. Also, regardless of the surface irregularities of the flat thin glass to be bonded, uneven resin is not applied to the sandwiched resin, so there is no variation in resin thickness.Therefore, due to variation in resin thickness on the substrates after lamination The micro waviness does not occur.

When hydrostatic pressure is used for pressurization or when a polymer elastic body is used for pressurization, the pressurization works, but since it works extremely uniformly, variations in resin thickness are not caused. Therefore, the micro-waviness due to the variation in the resin thickness does not occur on the substrates after bonding.

Furthermore, when the obtained laminated substrate of flat thin glass is provided with the function of a flat plate type microlens and is used as an opposing substrate for a liquid crystal display element or the like, it is possible to reduce variations in the thickness of the liquid crystal layer and display. It is possible to reduce color unevenness due to variations in the liquid crystal layer of the device.

[Brief description of drawings]

FIG. 1 is an outline of a process for laminating flat thin glass sheets under the condition that pressure is completely removed.

FIG. 2 is a schematic view of a process of laminating flat thin glass sheets using hydrostatic pressure for pressurization.

FIG. 3 shows an example of a flat thin glass laminating apparatus using another hydrostatic pressure for pressurization.

FIG. 4 is a schematic view of a step of laminating flat thin glass sheets using pressure by a polymer elastic body.

FIG. 5 is a surface profile of a laminated glass according to the present invention.

FIG. 6 is a liquid crystal display device using a laminated glass according to the present invention.

FIG. 7 is a surface profile of a laminated glass according to a conventional method.

[Explanation of symbols]

 10 Laminated Flat Substrate 11 Flat Substrate 12 Flat Thin Glass 13 Laminated Substrate with Microlens Function 14 Quartz Glass Substrate with Recesses 15 Thin Quartz Glass Substrate 21 (Transparent) Adhesive Resin 22 (Epoxy) Photocurable Resin 30 Pressurizing Device 31 Lower Pressurizing Surface Plate 32 Upper Pressurizing Surface Plate 33 UV Device 34 UV Ray 40 Hydrostatic Pressure Device 41 Hydrostatic Pressure Container 42 Fluid (Liquid, Gas) 43 O Ring 44 Valve 45 Piston 51 Polymer Elastic Body 61 Black matrix 62 Transparent counter electrode 63 Thin film transistor (p-Si TFT) 64 Transparent pixel electrode 65 Liquid crystal layer 71 Quartz glass substrate for TFT

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ichiro Matsunaka 3-5-11 Doshomachi, Chuo-ku, Osaka-shi, Osaka Inside Nippon Sheet Glass Co., Ltd.

Claims (9)

[Claims] 1. An adhesive resin is supplied to one surface of a flat substrate and / or a flat thin glass substrate, the flat thin glass substrate and the flat glass substrate are arranged so as to sandwich the resin feeding surface, and a pressing means is used to apply the resin. A method of expanding the resin sandwiched by pressing, curing the resin, and bonding the substrate and the flat thin glass substrate to each other, wherein the expansion of the resin is performed by applying a flat pressure platen. It is performed by being pressed, and after that, the pressure is completely removed,
A method for laminating a flat substrate, which comprises curing and laminating a resin. 2. An adhesive resin is supplied to one surface of a flat substrate and / or a flat thin glass substrate, the flat thin glass substrate and the flat glass substrate are arranged so as to sandwich the resin feeding surface, and pressure is applied by a pressing means. A method of adhering the substrate and the flat thin glass substrate after curing the resin sandwiched by pressing, curing the resin, and developing the resin, at least on the flat thin glass substrate surface, a rigid body. A method for laminating a flat substrate, which is carried out by directly acting a pressurized fluid without intervening, and further curing and laminating the resin in the pressurized state. 3. An adhesive resin is supplied to one surface of a flat substrate and / or a flat thin glass substrate, the flat thin glass substrate and the flat glass substrate are arranged so as to sandwich the resin feeding surface, and a pressing means is used to apply the resin. A method of laminating the resin sandwiched by pressing, curing the resin, and bonding the substrate and the flat thin glass substrate to each other. A method for laminating a flat substrate, which is performed by applying pressure through a body, and further curing and laminating the resin in the pressurized state. 4. The method for laminating flat substrates according to claim 1, wherein the substrate is a quartz glass substrate, and the flat thin glass substrate has a thickness of 0.5 mm or less. How to match. 5. The method for laminating a flat substrate according to claim 4, wherein the substrate is a quartz glass substrate, and the surface on the laminating surface side of the substrate has a fine concavo-convex pattern. A method for laminating a flat substrate in which an adhesive resin fills the fine concavo-convex pattern. 6. The method for laminating flat substrates according to claim 1, wherein the adhesive resin is a photocurable resin and has a viscosity of 1
To 50 poise flat substrate bonding method. 7. The method for laminating flat substrates according to claim 1, wherein the adhesive resin is a thermosetting resin and has a viscosity of 1
To 50 poise flat substrate bonding method. 8. A glass substrate having on its surface a plurality of substantially spherical or substantially cylindrical array-shaped recesses arranged one-dimensionally or two-dimensionally, and a transparent resin having a refractive index higher than that of the glass substrate of the array. In the method of manufacturing a flat-plate lens array in which concave portions are filled to form convex or lenticular lenses, (a) the glass substrate is quartz glass, and a hydrofluoric acid-resistant protective film is formed on the substrate (b) A step of forming a desired pattern on the protective film (c) A step of immersing the glass substrate in an etching solution containing hydrofluoric acid (d) A curability having a refractive index larger than that of the substrate on the surface of the substrate where the concave portion is formed Step of supplying transparent resin (e) A flat thin plate quartz glass substrate is bonded to the resin from the center of the thin glass substrate so that air bubbles do not enter, and then a flat pressure platen is attached. (F) After the resin is developed, the resin is cured by irradiating ultraviolet rays or performing heat treatment after the pressure is completely removed. And the process of bonding together The manufacturing method of the flat type lens array characterized by having the above process. 9. A method of manufacturing a flat plate type lens array in which convex or lenticular lenses having a substantially semicircular cross section formed on the surface of a plane substrate by an ion diffusion method are arranged one-dimensionally or two-dimensionally, a) the glass substrate is a glass containing monovalent alkali ions, and a step of forming a titanium film having an ion diffusion blocking function on the substrate. b) a step of forming a desired pattern on the protective film. ) A step of immersing the glass substrate in a molten salt having an ionic radius larger than the alkali ion to form a lens (d) A step of supplying a curable transparent resin onto the surface of the substrate on which the lens is formed (e) ) Bonding the flat thin quartz glass substrate to the resin from the center of the thin glass substrate so that air bubbles do not enter (f) The development of the resin is small. Both are performed by pressing the thin quartz glass substrate through a flat polymer elastic body. (G) After the resin is developed, it is irradiated with ultraviolet rays or is subjected to heat treatment as it is, Steps of curing and bonding resin A method of manufacturing a flat lens array having the above steps.