JP2678022B2 - Laminate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a laminate comprising three layers of a glass sheet layer, a heat adhesive resin sheet layer and a polycarbonate resin sheet layer.

In particular, public facilities for the purpose of weight reduction, safety improvement, etc.
The present invention relates to a laminate that can be favorably used as a safety glazing material for sports facilities or the like, or as a safety glazing material for vehicles.

[Conventional technology and its problems]

Glass sheets are widely used as glazing materials. Although glass is excellent in rigidity, hardness, weather resistance, chemical resistance, etc., on the other hand, it is heavy and is inferior in safety when broken due to a collision or an earthquake. Has difficult drawbacks.

On the other hand, a polycarbonate resin sheet is lighter than a glass sheet, has excellent impact resistance, and is also easy to carry out an ultraviolet ray blocking process and an infrared ray blocking process by blending various additives.

Currently, in order to improve the safety of glass, especially impact resistance and penetration resistance, laminated glass with a polyvinyl butyral resin (hereinafter abbreviated as PVB) sheet sandwiched in between is used as a safety glazing material for public facilities and exercise. Facility,
It is used in various fields such as automobiles, but this is insufficient and improvement is required.

Particularly, in recent years, glazing materials have been used in large quantities and have a large area in buildings such as public facilities and exercise facilities, and as a result, improvement in abrasion resistance to humans has been demanded.
In addition, even in glazing materials for automobiles, it is required to improve scratch resistance to passengers at the time of collision.
nical Paper Sevies 840391 includes Anti-Lacerative Wi
As ndshield Maferials, glass (2.29mm) / PVB (0.
95mm) / Glass (2.29mm) / Polyurethane (0.51mm) 4-layer structure and Glass (2.29mm) / PVB (0.95mm)
/ Glass (2.29mm) / PVB (0.38mm) / Polyester (0.
13mm) / hard coat 6 layer structure has been announced. However, these are conventional laminated glass to which polyurethane, polyester, etc. are added, and are high in cost. Therefore, there is a demand for a simple structure with improved abrasion resistance to humans.

As a glazing material for improving safety and lightness, many laminates of glass sheets and transparent synthetic resin sheets have been reported. However, these are not yet fully developed.

[Problems to be solved by the invention]

The problem with the laminated body of the glass sheet layer and the polycarbonate resin sheet layer is that the bimetal at the time of the thermal cycle test is caused by the adhesion of the glass sheet layer and the polycarbonate resin sheet layer and the difference in the thermal expansion coefficient between the glass sheet layer and the polycarbonate resin sheet layer. Glass sheet cracks due to effects,
It has impact resistance. The present invention solves these problems,
It is a laminate basically composed of three layers of a glass sheet layer, a heat adhesive resin sheet layer and a carbonate resin sheet layer.

[Means and Actions for Solving Problems]

The present invention is a laminate in which a glass sheet layer and a polycarbonate resin sheet layer are adhered via a heat-adhesive resin sheet layer, and the temperature at which the internal stress of the laminate is substantially 0 is -10. Exists in the temperature range from ℃ to less than 50 ℃,
The glass sheet layer has a thickness of 1 to 10 mm, the heat-adhesive resin sheet layer has a thickness of 0.05 mm or more and less than 0.4 mm, and the polycarbonate resin sheet layer has a thickness of 0.1 to 4 mm, (glass sheet layer thickness) / ( The laminated body is characterized in that the ratio of the thickness of the polycarbonate resin sheet layer) is 1 or more.

Further, the above three layers are basic, but as long as the above requirements are satisfied, a laminate having more than three layers including a sheet layer made of the same material as the sheet layer or a sheet material made of another material may be used if necessary.

The glass described in the present invention is a glass mainly composed of silicate glass, and sodium, potassium, lithium, calcium, magnesium, in the network structure of the polymerized silicate group,
It is stabilized by the entry of ions such as strontium. Soda-lime glass is a typical glass. Phosphorus silicate glass, borosilicate glass, etc. having a network copolymerized with silicate can also be used. Lead-alkali glass, alumina silicate glass, and quartz glass consisting only of SiO ₂ can also be used.

As the glass, tempered glass, semi-tempered glass, partially tempered glass, unstrengthened glass and the like can be used as necessary.

The polycarbonate resin described in the present invention is one of the most excellent glazing materials among synthetic resins in terms of transparency, weather resistance, hardness, bending strength, bending rigidity and the like. As the polycarbonate resin, an aromatic polycarbonate resin can be favorably used in the present invention, and a polycarbonate resin synthesized from bisphenol A can be particularly favorably used.

Various additives can be added to the polycarbonate resin within a range that does not significantly reduce the transparency. For example, UV absorbers, dyes and pigments, stabilizers and the like can be added.

The ultraviolet absorber referred to herein is a benzophenone-based compound represented by 2,2'-dihydroxy-4-methoxybenzophenone or 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2- (2 ′ -Hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenol) 5-
Chlorobenzotriazole, 2- (2-hydroxy-
3 ', 5-di-tert-butylphenol) benzotriazole type represented by 5-chlorobenzotriazole and substituted acrylonitrile type. Among them, the triazole type is particularly effective, and for example, 2- (2-hydroxy-5 '
-Methylphenyl) benzotriazole, 2- (2'-
The effect of hydroxy-3'-tert-butyl-5'-methylphenol) 5-chlorobenzotriazole is great.

The heat-adhesive resin sheet of the present invention is a transparent layer for adhering a glass sheet layer and a polycarbonate resin sheet layer by heating at a temperature of 80 ° C. or higher, and a preferable adhesive layer is composed of a tough soft resin layer. Polyvinyl butyral (abbreviated as PVB), ethylene-vinyl acetate copolymer (abbreviated as EVA), thermoplastic polyurethane, or modified products thereof can be preferably used. For PVB, PVB film that is generally used as an interlayer film for laminated glass can be used, and PVB having a molar ratio of hydroxyl group, acetyl group and butyral group of 25 to 50: 1 to 5:40 to 70 is most suitable. It can be used well. As a thermoplastic polyurethane, JP-A-60-80
The polyurethane interlayer shown in 59 can be used favorably. As a modified product of the partially saponified EVA, "Deumilan" (manufactured by Takeda Pharmaceutical Co., Ltd.) containing a hydroxyl group, an acetyl group, a carboxyl group and the like can be favorably used. The heat-adhesive resin sheet layer has a function of adhering the glass sheet layer and the polycarbonate resin sheet layer, and prevents cracking due to a bimetal effect during a cooling / heating cycle test caused by a difference in thermal expansion coefficient between the glass sheet layer and the polycarbonate resin sheet layer. And has the function of improving the impact resistance of the laminate of the present invention.

In order to obtain good impact resistance of the laminated product by adhering the glass sheet layer and the polycarbonate resin sheet layer through the heat-adhesive resin sheet layer, the heat-adhesive resin sheet layer is used in the adhering step. It is necessary that the temperature is 80 ° C or higher, more preferably 90 ° C or higher.
If the temperature is lower than 80 ° C, the adhesion is insufficient and the impact absorption performance is poor.

As a method for satisfactorily adhering the glass sheet layer and the polycarbonate resin sheet layer via the heat-adhesive resin sheet layer, after laminating the glass sheet layer, the heat-adhesive resin sheet layer and the polycarbonate resin sheet layer, the lamination Put the body under reduced pressure, after thoroughly removing the air between layers,
There is a method of bonding under heat and pressure conditions.

Various studies were conducted on the method of bonding under the above heating and pressurizing conditions. A method using a pinch roll, a method using a press device, and a method using an autoclave were examined. It was difficult to uniformly apply pressure to the adherend by the method of. Especially in the case of, it was impossible to deal with a curved surface. In that case, it is necessary to use an accurate mold corresponding to the shape of the adherend, and the glass is easily broken. On the other hand, in the case of this, it was found that the pressure can be uniformly applied without being influenced by the shape of the adherend, and the molding can be favorably performed.

In this heating and pressure-bonding step, since the heat-adhesive oil-contacting sheet exhibits adhesive performance in a temperature range of 50 ° C or higher, the laminate obtained by the above-mentioned step has a temperature range of 50 ° C or higher. When the temperature is changed to room temperature after completion of the bonding process, the shrinkage amount is different due to the difference in the thermal expansion coefficient between the glass sheet layer and the polycarbonate resin sheet layer, resulting in the bimetal. Due to the effect, internal stress is generated in the laminate. When the temperature is further lowered, the internal stress is increased and the glass sheet is cracked.

When the present invention is used as a safety glazing material for buildings, automobiles, etc., it may be placed in a temperature range of −40 to 80 ° C. in consideration of the temperature change of the outside air and the influence of direct sunlight. In the temperature range, it is necessary to suppress the generation of internal stress of the laminated body to a minimum, especially to suppress the internal stress generated in the glass sheet to a low level. In order to prevent the glass sheet from cracking, the internal stress of the laminated body is The temperature at which the temperature becomes substantially 0 is the central temperature range of the temperature range, that is, -10 ° C to 50 ° C.
It is necessary to exist in the range below.

When the laminated body of the glass sheet layer / heat-adhesive resin sheet layer / polycarbonate resin sheet layer, which is fixed in the temperature range of 50 ° C or more, is placed in the temperature range of -10 ° C or more and less than 50 ° C during bonding. Since the polycarbonate resin sheet layer has a larger shrinkage amount than the glass sheet layer, the following phenomenon occurs. The phenomenon is that when the laminated body is a laminate of flat ones, the glass sheet is a curved laminated body positioned on the convex surface side, and the layered body is a curved surface laminated shape in which the glass sheet is positioned on the convex surface side. In the case of the laminated body, the radius of curvature becomes small, and when the laminated body has a curved surface with the glass sheet positioned on the concave side, the radius of curvature becomes large. As a result, tensile internal stress is generated in the glass sheet in any case. When the temperature further decreases to -40 ° C, the above tendency becomes more remarkable.

In order for the glass sheet layer and the polycarbonate resin sheet layer to be satisfactorily adhered to each other via the heat-adhesive resin sheet layer so that the laminated product has good impact resistance, the heat-adhesive resin sheet is used in the adhering step. It is necessary that the temperature of the layer is preferably 80 ° C or higher, more preferably 90 ° C or higher.
If the temperature is lower than 80 ° C, the adhesion is insufficient and the impact absorption performance is poor. However, under these conditions, the temperature at which the internal stress of the finished laminated body becomes substantially 0 when it is adhered by the usual method, exists within the temperature range of -10 ° C to less than 50 ° C. Is difficult.

Here, in the bonding step, the temperature at which the internal stress of the finished laminate is substantially 0 while maintaining the heat-adhesive resin sheet layer at a preferable temperature in the bonding step is from -10 ° C to 50 ° C.
The present invention has been accomplished by finding a method of allowing the temperature to be lower than 0 ° C.

That is, as one method, when the glass sheet layer and the polycarbonate resin sheet layer are adhered to each other via the heat-adhesive resin sheet layer, an external force is applied in advance to fix the glass sheet layer and the polycarbonate resin sheet layer in a temperature range of 50 ° C. or more, and the planar shape is obtained. In the case of a laminated body, fix it with the glass sheet positioned on the concave side of the curved surface,
In the case of a curved laminated body such that the glass sheet is located on the convex side of the curved surface, fix the glass sheet with the radius of curvature larger than the specified radius of curvature, and place the glass sheet on the concave side of the curved surface. In the case of the laminated body of, the temperature at which the internal stress of the finished laminated body becomes substantially 0 by fixing it with the radius of curvature smaller than the predetermined radius of curvature is -10 ° C or more and less than 50 ° C. It was possible to exist in the temperature range of.

As another method, when the glass sheet layer and the polycarbonate resin sheet layer are bonded via the heat-adhesive resin sheet layer, the polycarbonate resin sheet layer is cooled by some method, and when the laminate is fixed, the polycarbonate resin sheet By fixing the temperature of the sheet layer at a temperature lower than the temperature of the glass sheet layer, the temperature at which the internal stress of the finished laminate becomes substantially 0 is -10 ° C or higher and 50 ° C or higher.
It was possible to exist in a temperature range of less than ° C.

In the present invention, the glass sheet layer 1 (eg, the first
The thickness shown in the figure is preferably 1 to 10 mm, more preferably 2 to 6 mm. Further, 3 to 5 mm is particularly preferable. If it is less than 1 mm, it breaks easily, and if it exceeds 10 mm, there is no weight reduction effect. The heat-adhesive resin sheet layer 2 aims to improve the impact resistance of the laminate of the present invention due to its impact absorption performance and to reduce the occurrence of internal stress of the laminate due to the temperature change. As such, the thickness is preferably 0.05 mm or more and less than 0.4 mm. The heat-adhesive resin sheet layer 2 is expensive such as PVB and thermoplastic polyurethane, and it is preferable that the heat-adhesive resin sheet layer 2 is thin and can achieve the purpose as far as possible. It was found that the purpose can be sufficiently achieved even in the range of 0.05 mm or more and less than 0.4 mm.

When it is less than 0.05 mm, the impact absorption performance and the performance to relieve the generation of internal stress are small. More preferably, it is 0.1 mm or more and less than 0.4 mm.

The thickness of the polycarbonate resin sheet layer 3 is 0.1 to 4 mm
Is preferred. When it is less than 0.1 mm, the impact resistance of the laminate of the present invention is low, and when it exceeds 4 mm, the internal stress of the laminate is increased due to the temperature change, and the laminate easily cracks at low temperature. More preferably, it is 0.2 to 2 mm.

Further, when comparing the glass sheet layer and the polycarbonate resin sheet layer, the glass sheet layer having a small elongation at break is easily broken. Therefore, when the ratio of (glass sheet layer 1) / (polycarbonate resin sheet layer 3) is preferably 1 or more, more preferably 3 or more, cracking does not easily occur when internal stress occurs.

The present invention basically comprises three layers of a glass sheet layer, a heat-adhesive resin sheet layer, and a polycarbonate resin sheet layer, but it can be further multilayered if necessary. In particular, it is preferable to provide a rigid coat layer on the surface of the polycarbonate resin sheet layer. The rigid coat layer is generally a thin transparent cured layer with a thickness of 1 to 50 μm that is coated on the surface of a transparent synthetic resin to harden the surface of the synthetic resin and improve scratch resistance, and is a polyfunctional acrylate rigid coat layer or polyorganosiloxane. The rigid resin coat layer is generally widely used and can be favorably used in the present invention. The rigid coat layer has a pencil hardness of preferably 4H or more, more preferably 5H or more.

The multifunctional acrylate rigid coat layer described here is a multifunctional acrylate rigid coat coating containing a multifunctional acrylate compound as a main component on a synthetic resin substrate surface by a method such as a dipping method, a spin method, a spray method, or a curtain flow method. After being coated, it is formed mainly by curing with ultraviolet irradiation.

A polyfunctional acrylate compound is a compound having a plurality of acryloyloxy or methacryloyloxy groups (CH ₂ = CR-COO-, R is H or CH ₃ ) at the terminal or side chain of the molecule, and is generally called an oligoacrylate. It is a thing. Examples of polyfunctional acrylate compounds are shown in the following table.

Among these polyfunctional acrylate compounds, compounds having excellent ultraviolet curability in air such as pentaerythritol acrylate can be particularly favorably used.

A photopolymerization initiator or a photosensitizer represented by a benzophenone-based or acetophenone-based substance is added to the polyfunctional acrylate-based hard coat coating for ultraviolet curing. Also, if necessary, various additives such as antioxidants,
A small amount of a light stabilizer, a thermal polymerization inhibitor, a stabilizer such as an ultraviolet absorber, a colorant, a fluorine-based or silicon-based surfactant for imparting smoothness to the coating film, and the like are added.

Examples of the polyorganosiloxane rigid coat layer include those starting from methyltrialkoxysilane and phenyltrialkoxysilane, those in which tetraalkoxysilane is combined, or mixtures with other resin paints such as methyltrialkoxy. Ethoxysilane / phenyltriethoxysilane reaction mixture (USP3451838), partial hydrolysis product of methyltriethoxysilane / acetic acid / sodium naphthenate (JP-A-50-143822), methyltrimethoxysilane / tetraethoxysilane / hydroxy groups at both ends Dimethylpolysiloxane / acidic catalytic reaction mixture (JP-A-50-11
6600), tetraalkoxysilane hydrolyzate / alkyltrialkoxysilane hydrolyzate / organic carboxylic acid alkali metal salt mixture (JP-A-48-56230), and the like.
In addition, those starting from polyorganosiloxane having a functional group such as vinyl group, epoxy group, amino group, for example, hydrolyzate of copolymer of vinylalkoxysilane and vinyl acetate / hydrolyzate of alkyl silicate / Vinyl acetate or acrylic acid, methacrylic acid, esters thereof / boron trifluoride monoethylamine complex (JP-A-48-26221), γ-glycidoxyalkyltrialkoxysilane ring-opening polymer (JP-A-50- 40674), β−
One or more reaction mixtures of (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane (JP-A-50-69174), β- (3,3, 4-epoxycyclohexyl) ethyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, and a reaction mixture of one or more of them with an epoxy prepolymer, diallyl phthalate, glycidyl methacrylate, etc. -69184), (2,3-epoxypropoxy) methyltrimethoxysilane / glycidyl methacrylate reaction mixture (JP-A-50-78639), aminoalkylalkoxysilane / epoxyalkylalkoxysilane partial hydrolysis reaction mixture (JP-A-48- 8487
8) etc. are used.

 Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 schematically shows a part of the cross section of the laminate of the present invention. 1-1 and 1-2 are planar laminates, FIGS. 1-3 and 1-4 are curved laminates in which the glass sheet layer is located on the convex side of the curved surface, FIGS. 1-5 and 1- 6
Is a curved laminated body in which the glass sheet layer is located on the concave side of the curved surface. Thus, the present invention also includes a curved laminate.

In FIG. 1, 1 is a glass sheet layer, 2 is a heat-adhesive resin sheet layer, 3 is a polycarbonate resin sheet layer,
4 is a rigid coat layer.

2 to 5 schematically show the manufacturing process of the laminated body manufactured by the present invention.

Method I-1 In FIG. 2, a flat glass sheet 5, a heat-adhesive resin sheet 6 and a polycarbonate resin sheet 7 are laminated as shown in FIG. 2-1. Further, as shown in FIG. 2-2, the laminated body 8 of the glass sheet 5 / heat-adhesive resin sheet 6 / polycarbonate resin sheet 7 is provided between a pair of hard bodies 9 and 10 having a certain radius of curvature, The glass sheet is inserted in such a state that it comes into contact with the convex surface side of the convex hard body 9. Then, the laminate obtained in the above step is put into a vacuum pack bag 11, the inside of the vacuum pack bag is evacuated, and then the vacuum pack is sealed to pre-compress the laminate 8. At this time, the laminated body 8
Is fixed in the radius of curvature of the hard bodies 9 and 10, that is, in the state of a curved laminated body in which the glass sheet is located on the concave side of the curved surface (Fig. 2-3). When this is heated and pressure-bonded using an autoclave under the condition that a good laminated body is obtained, the laminated body 12 obtained when returned to room temperature after the bonding step becomes flat (Fig. 2-4). . As a result, the temperature at which the internal stress of the laminate obtained by this method becomes substantially 0 exists in the temperature range of -10 ° C or higher and lower than 50 ° C.

Method I-2 In FIG. 3, as shown in FIG. 3-1, a curved glass sheet 13, a heat-adhesive resin sheet 14, a polycarbonate resin sheet 15, the glass sheet 13 being the convex side of the curved surface of 15 above. Stack so that it is located at. Further, as shown in FIG. 3-2, the above-mentioned glass sheet 13 / heat-adhesive resin sheet 14 / polycarbonate resin sheet is provided between a pair of hard bodies 17 and 18 having a slightly larger radius of curvature than the glass sheet 13. Insert 15 stacks 16. After that, the laminate obtained in the above step is put into a vacuum pack bag 19, the inside of the vacuum pack bag is evacuated, the vacuum pack is sealed, and the laminate 16 is pre-compressed. At this time, the laminated body 15 is in a state of being fixed to a radius of curvature of the hard bodies 17 and 18, that is, a radius of curvature slightly larger than a predetermined radius of curvature of the glass sheet 13 (FIG. 3-).
3) When this is heated and pressure-bonded by using an autoclave under the condition that a good laminated body is obtained, the radius of curvature of the laminated body 20 obtained when the temperature is returned to room temperature after the completion of the adhesion step is the glass before lamination. It has the same radius of curvature as the seat 13 (Fig. 3-
4). As a result, the temperature at which the internal stress of the curved layered body obtained by this method becomes substantially 0 is -10 ° C to 50 ° C.
Will be in the temperature range below.

Method I-3 In FIG. 4, as shown in FIG. 4-1, a curved glass sheet 21, a heat-adhesive resin sheet 22, and a polycarbonate resin sheet 23 are used, the glass sheet 21 being the concave side of the curved surface of the laminate. Stack so that it is located at. Further, as shown in FIG. 4-2, the glass sheet 21 / heat-adhesive resin sheet 22 / polycarbonate resin sheet is provided between a pair of hard bodies 25 and 26 having a slightly smaller radius of curvature than the glass sheet 21. Insert the stack 24 of 23. After that, the laminate obtained in the above step is put into a vacuum pack bag 27, the inside of the vacuum pack bag is evacuated, the vacuum pack is sealed, and the laminate 24 is pre-compressed. At this time, the laminated body 24 is fixed to a radius of curvature of the hard bodies 25 and 26, that is, a radius of curvature slightly smaller than a predetermined radius of curvature of the glass sheet 21 (FIG. 4).
3). When this is heated and pressure-bonded under a condition that a good laminate is obtained using an autoclave, the radius of curvature of the laminate 28 obtained when the temperature is returned to room temperature after the completion of the adhesion step is the glass sheet 21 before lamination. It is the same as the radius of curvature (Fig. 4-
4). As a result, the temperature at which the internal stress of the curved layered body obtained by this method becomes substantially 0 is -10 ° C to 50 ° C.
Will be in the temperature range below.

Method II In FIG. 5, as shown in FIG. 5-1, a curved glass sheet 29, a heat-adhesive resin sheet 30, and a polycarbonate resin sheet 31 are placed so that the glass sheet 29 is located on the convex side of the curved surface. To stack. The laminated body 32 of the glass sheet 29 / heat-adhesive resin sheet 30 / polycarbonate resin sheet 31 thus obtained is put into a vacuum pack bag 34, and the inside of the vacuum pack bag is evacuated, and then the vacuum pack. Seal the
The laminated body 32 is pre-compressed. Next, the laminated body 32 is placed on the convex hard body 33 whose surface temperature can be arbitrarily controlled in the autoclave so that the surface of the polycarbonate resin sheet layer side is in contact with the hard body 33 (FIG. 5). -2). This is heated and pressure-bonded using an autoclave under the condition that a good laminate is obtained. At this time, by setting the surface temperature of the hard body 33 to a temperature lower than the internal temperature of the autoclave, the temperature of the polycarbonate resin sheet 31 is lower than the temperature of the glass sheet 29, and the laminated body 32 is
Since they are bonded and fixed, the radius of curvature of the laminated body 35 obtained when returning to room temperature after the bonding process is the same as the radius of curvature of the glass sheet 29 before lamination (FIG. 5-3). As a result, the temperature at which the internal stress of the laminate obtained by this method becomes 0 is in the temperature range of -10 ° C or higher and lower than 50 ° C.

The present method can be similarly applied to a curved surface-shaped laminate in which the flat laminated body and the glass sheet are located on the concave side of the curved surface. In the case of a planar laminated body, the surface of the polycarbonate resin sheet of the laminated body is A hard body that has a corresponding flat surface and whose surface temperature can be arbitrarily controlled in the autoclave may be used, and in the case of a curved laminated body such that the glass sheet is located on the concave side of the curved surface, Has a concave curved surface that corresponds to the radius of curvature of the polycarbonate resin sheet,
A hard body whose temperature on the concave side surface can be arbitrarily controlled in the autoclave may be used.

As a result, the radius of curvature of the curved laminate obtained by returning to room temperature after the bonding step is the same as the radius of curvature of the glass sheet before lamination, and the internal stress of the curved laminate is substantially The temperature which becomes 0 exists in the temperature range of -10 ° C or higher and lower than 50 ° C.

The internal stress of a laminate basically composed of three layers of glass sheet layer / heat-adhesive resin sheet layer / polycarbonate resin sheet layer can be measured by various methods, but we measure it using a photoelastic method experimental device. did.

The photoelastic method experimental device means that when an external force is applied to an isotropic, isotropic and transparent elastic body, stress is generated in the elastic body and the birefringence, that is, the photoelastic effect is optically exhibited by the temporary anisotropy. This is a device for measuring this photoelastic effect by utilizing, and it is possible to similarly measure the occurrence of internal stress due to the bimetal effect of the laminated body.

When polarized light is vertically incident on a sample in which internal stress is generated, the light ray traveling in the sample becomes two plane polarized light oscillating in the principal stress direction, and these two light rays are proportional to the difference in principal stress. Phase difference occurs. This is observed as a fringe due to interference of light through the analyzer (polarizing plate).
Whether or not internal stress is generated will be observed depending on whether or not this interference fringe is generated.

The relationship between the change in shape of the laminate of the present invention and the internal stress will be described below.

When a laminated body is manufactured using a flat glass sheet and a transparent hard synthetic resin sheet, when the finished laminated body has a planar shape, internal stress is applied to the glass sheet layer of the laminated body. It is shown that no fringes due to light interference are observed in the image obtained by the photoelasticity test device, and the internal stress is 0.

The same applies to the curved surface laminated body, and when the curvature radius R of the finished curved surface laminated body is R = R _{0 with} respect to the curvature radius R ₀ of the glass sheet used as the material. , Showing that no internal stress is applied to the glass sheet layer of the curved surface laminate, no fringes due to light interference were observed in the image by the photoelasticity test device, and internal stress was not observed. Is 0.

If internal stress is generated in the polycarbonate resin sheet layer of the laminate of the present invention, stress is also applied to the glass sheet layer by its influence, resulting in a change in the shape of the glass sheet layer. It will be. Therefore, when the shape of the glass sheet layer in the laminated body and the shape of the glass sheet before laminating are the same, it can be considered that the generation of internal stress is zero.

〔Example〕

First, the method for measuring the impact resistance of the laminate of the present invention will be described.

The impact resistance of the laminate can be measured by various methods,
We carried out drop weight impact tests on small sample (10 cm ^square ) of various laminated structures using Drop weight impact tester manufactured by Rheometrics, and compared the measurement results.

This device has a load cell embedded in the tip of the missile of the drop weight impact tester, which can measure the time change of the impact force when the missile collides with the sample, and the computer process processes the impact absorption energy. You can also know the changes over time.

In the following examples, a quadric curved surface laminated body is described for the purpose of clarifying the content of the present invention, but the present invention can be sufficiently applied to a planar laminated body and a cubic curved surface laminated body. .

The glass sheet used in this example is an unstrengthened glass sheet. The PVB sheet used was "Esretck Film" HI type manufactured by Sekisui Chemical Co., Ltd. As the polycarbonate resin sheet, "Sunloid Polycaace" manufactured by Simplified Plastics Co., Ltd. was used.

Example 1.1 Secondary curved glass sheet having a radius of curvature of 2500 mm ^R and a thickness of 5 mm
13, 0.38 mm thick PVB sheet 14 and 1 mm thick polycarbonate resin sheet 15 are laminated so that the glass sheet 13 is located on the convex side of the curved surface, as shown in FIG. Next curvature radius 2700mm ^R of the secondary curved and the concave rigid body 17 and the curvature radius of 2700mm convex rigid bodies were secondary curved ^R 18,
The glass sheet / PVB sheet / polycarbonate resin sheet laminate 16 is inserted between them (Fig. 3-2). Next, the whole body including the hard body is put in a vacuum pack bag 19, a vacuum is applied in the vacuum pack bag, the vacuum pack is sealed, and the laminate 16 is pre-compressed (FIG. 3-3). Using an autoclave, this was treated and bonded under the conditions of a temperature of 120 ° C. and a pressure of 10 kg / cm ² for 10 minutes. Thereafter, the vacuum pack bag 19 and the hard bodies 17 and 18 were removed to obtain a quadric curved surface laminated body 20 (Fig. 3-4). Table 1 shows the evaluation results of the quadratic curved surface layered body 20 during the thermal cycle test.

Example 1.2 Secondary curved glass sheet having a radius of curvature of 2500 mm ^R and a thickness of 3 mm
13, 0.38 mm thick PVB sheet 14, 1 mm thick polycarbonate resin sheet 15, using the concave hard body 17 and the convex hard body 18 having a quadric curved surface with a radius of curvature of 3000 mm ^R. The secondary curved surface layered body 20 was obtained by bonding in the same manner as in (1). Table 1 shows the evaluation results of the quadratic curved surface layered body 20 during the thermal cycle test.

Example 2 A quadric curved glass sheet having a radius of curvature of 2500 mm ^R and a thickness of 5 mm
As shown in FIG. 5A, a PVB sheet 30 having a thickness of 29, 0.38 mm and a polycarbonate resin sheet 31 having a thickness of 1 mm are laminated so that the glass sheet 29 is located on the convex side of the curved surface of the laminate.
This is put in a vacuum pack bag 34, the inside of the vacuum pack bag is evacuated, the vacuum pack is sealed, and the laminate 32 is pre-compressed. This is a convex hard body having a quadric surface with a radius of curvature of 2500 mm ^R , and is placed on the convex hard body 32 whose temperature on the convex surface can be arbitrarily controlled in the autoclave (Fig. 5-2). Place these in an autoclave, treat them for 10 minutes under the conditions of an autoclave temperature of 120 ° C, a pressure of 10 kg / cm ² , and a convex surface temperature of the convex hard body of 20 ° C.
A next curved surface-shaped laminate 35 was obtained (Fig. 5-3). Table 1 shows the evaluation results of the quadratic curved surface laminated body 35 during the thermal cycle test.

Comparative Example 1 Curvature radius 2500 mm ^R , thickness 5 mm secondary curved glass sheet
36, a PVB sheet 37 having a thickness of 0.38 mm and a polycarbonate resin sheet 38 having a thickness of 1 mm are laminated so that the glass sheet 36 is positioned on the convex side of the curved surface of the laminate as shown in FIG.
This is put in a vacuum pack bag 40, the inside of the vacuum pack bag is evacuated, the vacuum pack is sealed, and the laminate 39 is pre-compressed (FIG. 6-2). This was treated by using an autoclave under the conditions of a temperature of 120 ° C. and a pressure of 10 kg / cm ² for 10 minutes to bond them to obtain a quadric curved surface layered body 41 (FIG. 6-3). Said 2
Table 1 shows the evaluation results of the next curved surface layered body 41 during the thermal cycle test.

In Example 3 and Comparative Example 2 shown below, a flat sample having a size of 10 cm ^square was manufactured, and an impact resistance test was carried out for comparison.

Example 3.1 10 cm ^□ , a flat glass sheet 42 having a thickness of 3 mm, a PVB sheet 43 having a thickness of 0.38 mm, a polycarbonate resin sheet 44 having a thickness of 1 mm, by the above method II using an autoclave, a temperature of 120 ° C., a pressure of 10 kg / cm ² Treated for 10 minutes under the conditions of laminate 4
Got 7. Table 2 shows the results of the impact resistance test of the laminate 47.

Example 3.2 10 cm ^□ , a flat glass sheet 42 having a thickness of 5 mm, a PVB sheet 43 having a thickness of 0.38 mm, and a polycarbonate resin sheet 44 having a thickness of 1 mm were adhered by the same method as in Example 3.1 to obtain a laminate 47. . Table 2 shows the results of the impact resistance test of the laminate 47.

Comparative Example 2.1 10 cm ^□, laminated PVB sheet 49 of flat glass sheets 48 and 0.38mm thicknesses of 2mm as shown in Figure 8-1. The laminated body 50 is placed in a vacuum pack bag 51, the inside of the vacuum pack bag is evacuated, and then the vacuum pack is sealed to obtain the above laminated body.
Pre-press 50 (Fig. 8-2). This was treated with an autoclave under the conditions of a temperature of 100 ° C. and a pressure of 10 kg / cm ² for 10 minutes to bond them. Then, the vacuum pack bag 51 was removed to obtain a laminated glass 52. Table 2 shows the results of the impact resistance test of the laminated glass 52.

Comparative Example 2.2 10 mm ^□, the PVB sheets 49 of planar glass sheets 48 and 0.38mm thicknesses of 3 mm, is by connexion bonded to the same manner as in Comparative Example 2.1, to give a laminated glass 52. Table 2 shows the results of the impact resistance test of the laminated glass 52.

An impact resistance test of the laminate of the present invention was conducted using the Drop weight impact tester manufactured by Rheometrics. An impact test was conducted from the polycarbonate resin sheet side of the laminate for the purpose of evaluating the abrasion resistance to humans when the laminate of the present invention is used as various safety glazing materials.

Test conditions: Sample presser diameter: 3 inch φ Missile diameter: 1/2 inch φ Missile weight: 3.75 kg Collision speed: 10 m / sec Laminated glass with the same total thickness (glass sheet / P
A comparison of the impact test results of the VB sheet / glass sheet and the laminate of the present invention is shown in FIG. A large difference is seen in the time change of the impact force, and in the case of the laminated glass (Comparative Example 2), there is one sharp impact force peak.
In the case of the laminate of the present invention (Example 3), there are two sharp impact force peaks. This is a phenomenon caused by a difference between the time of destruction of the glass sheet and the time of destruction of the polycarbonate resin sheet upon impact. Comparing the total amount of absorbed energy, the laminated body of the present invention is higher than the laminated glass, and the laminated body of the present invention has a sufficiently improved impact resistance performance than the laminated glass.

[Brief description of the drawings]

FIG. 1 schematically shows a part of the cross section of the laminate of the present invention. 2 to 5 are cross-sectional views of the curved surface layered body manufactured by the present invention for each step. FIG. 6 shows a cross-section of a curved layered body manufactured by a comparative example of the present invention for each step. FIG. 7 and FIG. 8 show cross-sections of test pieces used for impact resistance test and the like for each step. FIG. 9 shows the results measured by the impact resistance test. In FIG. 1, 1: glass sheet layer, 2: adhesive sheet layer,
3: Polycarbonate resin sheet layer, 4: Rigid coat layer

Claims (1)

(57) [Claims] 1. A laminate comprising a glass sheet layer and a polycarbonate resin sheet layer adhered to each other via a heat-adhesive resin sheet layer, and the internal stress of the laminate is substantially zero.
The temperature to be present in the temperature range of -10 ℃ or more and less than 50 ℃, the thickness of the glass sheet layer is 1 to 10 mm, the thickness of the heat-adhesive resin sheet layer is 0.05 mm or more and less than 0.4 mm, the polycarbonate resin sheet layer A laminate having a thickness of 0.1 to 4 mm and a ratio of (glass sheet layer thickness) / (polycarbonate resin sheet layer thickness) of 1 or more.