JP5813475B2 - Foamed laminated glass and method for producing the same - Google Patents

Description

  The present invention relates to foamed laminated glass and a method for producing the same.

  For laminated glass, PVB (polyvinyl butyral resin) or other film is used as an adhesive film, and heat and pressure are used to make the film (film alignment), and two glass plates with a width of about 1mm to 4mm are created. There is a method of bonding two glass plates by pouring a liquid resin into the space and causing a chemical reaction (resin combination).

In resin matching, a manufacturing method is known in which a spacer is mounted between two glass plates, an acrylic monomer and a polymerization initiator are injected into the gap, and then polymerization is performed (for example, see Patent Document 1). .
On the other hand, as a method for producing a resin foam, there is a method in which a polymerization initiator of an acrylic acid monomer partially made into an alkali metal salt is foamed using an azo polymerization initiator that decomposes during polymerization and generates nitrogen gas. Yes (see, for example, Patent Document 2).

Japanese Patent No. 2619288 JP-A-8-253615

  In the laminated glass described in Patent Document 1, it is not desirable that bubbles are generated between the glass plates, and thus those that generate bubbles have not been used as products. Conventionally, a laminated glass in which bubbles are generated between glass plates is only a defective product, and there has been no idea to produce a product by generating a large number of bubbles. When considering the production of a laminated glass having a large number of bubbles, it is conceivable to use the resin foam described in Patent Document 2 as the resin, but in the resin foam described in Patent Document 2, the amount of generated foam Therefore, it was not suitable for laminated glass provided in a thin gap.

  The present invention has been made paying attention to such a problem, and an object of the present invention is to provide a novel laminated glass containing a large number of bubbles between glass plates and a method for producing the same.

The method for producing foamed laminated glass according to the present invention comprises providing a mixture of acrylic syrup containing at least an acrylic monomer or an acrylic oligomer and an azo polymer polymerization initiator between two glass plates, and the acrylic syrup. And the azo polymer polymerization initiator is heated at a temperature of 75 to 85 ° C. for 2 to 12 hours and then cured by heating at a temperature of 90 to 100 ° C. for 4 to 12 hours and contained in the acrylic syrup. The acrylic monomer or acrylic oligomer is polymerized with the azo polymer polymerization initiator to form a cured acrylic syrup containing nitrogen gas bubbles between the glass plates, and the cured acrylic syrup is used to bond the glass plates together. It is characterized by doing.
In the method for producing foamed laminated glass according to the present invention, a large amount of nitrogen gas bubbles are generated from the azo polymer polymerization initiator when the acrylic monomer or acrylic oligomer contained in the acrylic syrup is polymerized. A cured acrylic syrup containing nitrogen gas bubbles is formed between the plates. Each glass plate is bonded by a cured acrylic syrup containing foam. Foamed laminated glass containing a large number of bubbles between glass plates is new and highly designable, and can broaden the application of laminated glass.
In the present invention, the acrylic syrup means a substance that contains at least an acrylic monomer or an acrylic oligomer, is liquid at normal temperature, and is cured by a polymerization initiator.

In the method for producing foamed laminated glass according to the present invention, a spacer is provided between each glass plate so as to surround the space and hermetically close the space excluding the injection hole, and the acrylic syrup and the space from the injection hole to the space. It is preferable to inject a mixture with an azo polymer polymerization initiator and provide between each glass plate.
In this case, as the polymerization of the acrylic syrup proceeds, the generated foam is blocked by the surrounding spacer and does not escape to the outside, so that the foam can be efficiently contained in the cured acrylic syrup.

The spacer is composed of a double-sided adhesive tape, and the spacer is arranged in a ring on one side of one glass plate and attached, and the spacer is attached to one side of the other glass plate and a release paper is attached to a part of the one side It is preferable that the space is formed between each glass plate and the spacer with the position of the release paper as the injection hole.
In this case, the formation of the injection hole and the space for injecting the mixture of acrylic syrup and the azo polymer polymerization initiator can be facilitated.

In the method for producing foamed laminated glass according to the present invention, the mixture of the acrylic syrup and the azo polymer polymerization initiator is heated at a temperature of 75 to 85 ° C. for 2 to 12 hours, and then a temperature of 90 to 100 ° C. By heating and curing for 4 to 12 hours , the generation of bubbles is stabilized, the unevenness of the bubbles is reduced, the bubbles are uniformly generated throughout the cured acrylic syrup, and the variation in the size of the bubbles is reduced. be able to.

The foamed laminated glass according to the present invention has two glass plates and an acrylic syrup cured product, and the acrylic syrup cured product contains an azo polymer polymerization initiator and nitrogen gas bubbles inside, Provided between the glass plates, the glass plates are bonded to each other, and the bubbles are uniformly generated in the entire cured acrylic syrup and have a size within a range of 2 mm to 10 mm.
The foamed laminated glass according to the present invention can be suitably produced by the method for producing a foamed laminated glass according to the present invention. Since the foamed laminated glass according to the present invention includes a large number of bubbles between the glass plates, it is novel and has high design properties. In the present invention, the cured acrylic syrup means a product obtained by curing at least a liquid acrylic syrup at room temperature with a polymerization initiator, which contains at least an acrylic monomer or an acrylic oligomer.

  ADVANTAGE OF THE INVENTION According to this invention, the novel foamed laminated glass containing many bubbles between glass plates and its manufacturing method can be provided.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 and 2 show the temperature conditions of the method for producing foamed laminated glass according to the embodiment of the present invention.
In the method for producing foamed laminated glass according to the embodiment of the present invention, a spacer is provided between two glass plates so as to surround the space and hermetically close the space except for the injection hole. The spacer is made of double-sided adhesive tape. A spacer is annularly arranged on one side of one glass plate and attached. The annular arrangement may be a square shape or a circular shape as long as it is a closed shape. A spacer is attached to one side of the other glass plate with a release paper attached to a part of the one side. Thus, a space is formed between each glass plate and the spacer using the position of the release paper as the injection hole.

  A mixture of acrylic syrup and an azo polymer polymerization initiator is injected into the space from the injection hole at the position of the release paper and provided between the glass plates. After the injection, the release paper at the position of the injection hole is removed, and a spacer is attached to the glass plate to close the injection hole. A mixture of acrylic syrup and an azo polymer polymerization initiator is heated at a temperature of 75 to 100 ° C. to be cured. Preferably, the mixture of acrylic syrup and azo polymer polymerization initiator is heated at a temperature of 75 to 85 ° C. for 2 to 12 hours, and then heated at a temperature of 90 to 100 ° C. for 4 to 12 hours. The acrylic monomer or acrylic oligomer contained in the acrylic syrup is polymerized by the azo polymer polymerization initiator to form a cured acrylic syrup containing nitrogen gas bubbles between the glass plates. Each glass plate is bonded with a cured acrylic syrup.

The two glass plates are not limited in size, thickness, color, nature, etc. In addition, one or more glass plates are further stacked on two glass plates, an acrylic syrup cured product containing nitrogen gas bubbles is formed between the glass plates, and each glass plate is bonded with the acrylic syrup cured product. Also good. As the spacer, an airtight pressure-sensitive adhesive material can be preferably used. In addition to an airtight double-sided adhesive tape, elastic butyl rubber, thermoplastic rubber, or the like can be used.
The gap between the two glass plates is not limited, but is preferably in the range of about 1 mm to 4 mm. The injection hole may be provided without completely closing the space when the spacer is disposed on the glass plate, or may be provided after the space is completely closed.

  Acrylic syrup comprises at least an acrylic monomer or an acrylic oligomer, is liquid at normal temperature, and is cured by a polymerization initiator. As the acrylic monomer or acrylic oligomer contained in the acrylic syrup, an acrylic ester monomer or oligomer, a derivative thereof, or a mixture of two or more thereof can be used. For example, methyl (meth) acrylate, Ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylic Lauryl acid, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-propyl (meth) acrylate, chloro-2-hydroxyethyl (meth) acrylate, Mono (meth) acrylic acid diethylene glycol, (meth) acrylic Methoxyethyl acrylate, and (meth) acrylate, glycidyl (meth) acrylate, dicyclopentanyl (meth) acrylate and dicyclopentenyl and (meth) Isoboronoru acrylic acid. The acrylic syrup may contain a monomer other than acrylic or a rubbery polymer. Examples of rubber-like polymers include acrylic rubber, polybutadiene, polyisoprene, butadiene-isoprene copolymer, polychloroprene, styrene-butadiene copolymer, conjugated diene rubbers or hydrogenated products thereof, and ethylene-propylene copolymers. Examples thereof include olefin rubbers such as rubber, ethylene-propylene-diene copolymer rubber, ethylene-vinyl acetate copolymer rubber, polyisobutylene rubber, thermoplastic elastomers such as silicon rubber, fluorine rubber, polyurethane elastomer, and polyester elastomer. .

By adjusting the viscosity of the acrylic syrup to be used, the shape of bubbles at the time of curing can be changed to various shapes such as a shape close to a perfect circle or a shape in which an ellipse is distorted in a complicated manner like an amoeba. When the viscosity is reduced, the shape of the bubble at the time of curing becomes a shape close to a perfect circle or an ellipse, and when the viscosity is increased, it becomes a complicated shape like an amoeba. The viscosity can be adjusted by mixing acrylic syrups having different viscosities in an arbitrary ratio. The cured acrylic syrup can be colored with pigments, dyes and the like.
As the azo polymerization initiator, known azo polymerization initiators can be used, such as azobisisobutyronitrile (AIBN), 2,2′-azobis (2-methylpropionitrile), 2,2 ′. -Azobis (2-methylbutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2-cyclopropylpropionitrile), 1,1'-azobis ( Cyclohexane-1-carbonitrile), dimethyl-2,2′-azobis (2-methylpropionate), and the like.

  Such azo polymerization initiators may be used alone or in combination, or an azo polymerization initiator and a polymerization initiator other than azo may be used in combination. In the present invention, such an azo polymerization initiator is used in an amount of 0.1 to 10 parts by weight, preferably 0.5 to 2 parts by weight, particularly preferably 0.65 to 1 part by weight, based on 100 parts by weight of acrylic syrup. Can do. If the amount of the azo polymerization initiator is small, the generation of bubbles becomes insufficient, which is not preferable.

The temperature and time for heating and polymerizing acrylic syrup are 2 to 12 hours at a temperature of 75 to 85 ° C. in the first stage, preferably 6 hours at 80 ° C., and 4 to 12 hours at a temperature of 90 to 100 ° C. in the second stage. , Preferably at 90 ° C. for 6 hours.
It is preferable to stir and degas for several minutes before injecting the mixture of acrylic syrup and azo polymer polymerization initiator into the space. Thereby, it becomes easy to generate a bubble uniformly in the whole acrylic syrup hardened | cured material.

  When the acrylic syrup is polymerized, a large amount of nitrogen gas bubbles are generated from the azo polymer polymerization initiator, and a cured product of acrylic syrup containing nitrogen gas bubbles is formed between the glass plates. Since the foam contained in the cured acrylic syrup is blocked by the surrounding spacer and does not escape to the outside, the foam can be efficiently contained in the cured acrylic syrup. Bubbles are generated by heating a mixture of acrylic syrup and azo polymer polymerization initiator in two stages at a temperature of 75 to 85 ° C. for 2 to 12 hours and at a temperature of 90 to 100 ° C. for 4 to 12 hours. Can be stabilized, foam unevenness can be reduced, foam can be uniformly generated in the entire cured acrylic syrup, and variation in foam size can be reduced. For this reason, it looks good. By heating in two stages under the above conditions, the foam can be substantially contained in the range of 2 mm to 10 mm.

Injection hole for injecting a mixture of acrylic syrup and azo polymer polymerization initiator by using the double-sided adhesive tape as a spacer and the position of the release paper of the spacer with the release paper attached to a part as the injection hole And space formation can be facilitated.
Foamed laminated glass containing a large number of bubbles between glass plates is new and highly designable, and can broaden the application of laminated glass. Foamed laminated glass can be used, for example, as partition glass or design glass.

<Glass tape pasting>
A double-sided adhesive tape serving as a spacer was attached to four sides of a single glass plate (500 mm × 1000 mm). A double-sided adhesive tape having a thickness of 1 mm to 4 mm was used. Another glass of the same size was bonded to the glass on which the spacer was installed, and the three sides were bonded to create a space between the two glass plates. The spacer on one side of the four sides had a release paper on one side, and the position was used as a resin injection hole.

<Resin preparation>
100 parts by mass of a commercially available acrylic syrup having a viscosity of 10 mPa · s based on 40% by mass of methyl methacrylate and 26% by mass of n-butyl acrylate, and an azo polymer polymerization initiator (azobisisobutyronitrile (AIBN )) 0.75 part by mass was stirred and mixed for 8 minutes to defoam and prepare a resin.

<Resin injection>
After injecting the prepared resin into the space between the injection hole and the glass plate, the release paper at the position of the injection hole was removed, and a spacer was attached to the glass plate to close the injection hole. At this time, a syringe equipped with an injection needle having an outer diameter of 0.5 to 1.2 mm was used, and the injection needle was inserted into the spacer portion to remove excess air.

<Heat curing>
The glass plate with the resin injected in between was put into a heating furnace set at 80 ° C. The temperature conditions of the heating furnace were changed as in the following (1) to (9), and acrylic syrup was heated and polymerized to produce foamed laminated glass.
(1) After heating at 60 ° C. for 12 hours, the temperature was lowered to room temperature in 2 hours.
(2) After heating at 70 ° C. for 12 hours, the temperature was lowered to room temperature in 2 hours.
(3) After heating at 80 ° C. for 12 hours, the temperature was lowered to room temperature in 2 hours.
(4) After heating at 90 ° C. for 12 hours, the temperature was lowered to room temperature in 2 hours.
(5) After heating at 100 ° C. for 12 hours, the temperature was lowered to room temperature in 2 hours.
(6) After heating at 80 ° C. for 6 hours, the temperature was raised to 90 ° C. for 1 hour, heated at 90 ° C. for 6 hours, and then cooled to room temperature in 2 hours.
(7) After heating at 80 ° C. for 2 hours, the temperature was raised to 90 ° C. for 1 hour, heated at 90 ° C. for 9 hours, and then cooled to room temperature in 2 hours.
(8) After heating at 80 ° C. for 2 hours, the temperature was lowered to 70 ° C. for 1 hour, heated at 70 ° C. for 9 hours, and then lowered to room temperature in 2 hours.
(9) After heating at 80 ° C. for 6 hours, the temperature was raised to 90 ° C. for 1 hour, heated at 90 ° C. for 3 hours, and then lowered to room temperature in 2 hours.

<Result>
When it was cured at a temperature in the vicinity of 75 ° C. to 100 ° C. as in (3), (4), and (5), countless bubbles were generated. However, when cured at a relatively low temperature of 60 ° C. or 70 ° C. as in (1) and (2), the gas tends to concentrate on the glass-resin interface, and the resin is peeled off from the glass plate. It became. (6) When heating at 75 to 85 ° C. for 2 to 12 hours and then heating at 90 to 100 ° C. for 4 to 12 hours and performing two-stage heating as in (6) and (7), Compared with (3), (4), and (5), the generation of bubbles was stable, the bubbles were uniformly generated throughout the cured acrylic syrup, and there was little variation in the size of the bubbles. The generated bubbles were large enough to fit within the range of 2 mm to 10 mm and looked good. However, when the temperature was lowered to 70 ° C. and cured as in (8), the generation of bubbles was insufficient. When the curing time after raising the temperature to 90 ° C. as in (9) was 3 hours or less, a part where foaming was insufficient was generated.

Claims (4)

An acrylic syrup containing at least an acrylic monomer or an acrylic oligomer and an azo polymer polymerization initiator are provided between two glass plates, and the mixture of the acrylic syrup and the azo polymer polymerization initiator is provided. After heating at a temperature of 75 to 85 ° C. for 2 to 12 hours and curing at a temperature of 90 to 100 ° C. for 4 to 12 hours, the acrylic monomer or acrylic oligomer contained in the acrylic syrup is converted to the azo-based polymer. A method for producing a laminated glass with foam comprising polymerizing with a molecular polymerization initiator to form a cured acrylic syrup containing bubbles of nitrogen gas between each glass plate, and bonding each glass plate with the cured acrylic syrup .   A spacer is provided between each glass plate so as to surround the space and airtightly close the space except for the injection hole, and the mixture of the acrylic syrup and the azo polymer polymerization initiator is injected into the space from the injection hole. The method for producing a laminated glass with bubbles according to claim 1, wherein the method is provided between the glass plates.   The spacer is composed of a double-sided adhesive tape, and the spacer is arranged in a ring on one side of one glass plate and attached, and the spacer is attached to one side of the other glass plate and a release paper is attached to a part of the one side 3. The method for producing foamed laminated glass according to claim 2, wherein the space is formed between each glass plate and the spacer with the position of the release paper used as the injection hole by pasting with a sheet. Two glass plates and an acrylic syrup cured product, the acrylic syrup cured product includes an azo polymer polymerization initiator and a nitrogen gas bubble inside, and is provided between the glass plates. A foamed laminated glass characterized in that the foam is a size that is uniformly generated throughout the cured acrylic syrup and is within a range of 2 mm to 10 mm.