JP4251426B2 - Adhesive and method for producing the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention mainly relates to an adhesive capable of bonding a glass member to glass, metal, ceramics, and the like, and more particularly to an adhesive having a heat resistance of 300 ° C. or higher and low gas permeability and a method for manufacturing the same. Is.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, glass and glass-bonded members are excellent in soundproofing, heat insulation, and the like, and thus are used for architectural window glass, vehicle window glass, freezer window glass, and the like. Further, a member obtained by bonding glass and a metal plate or glass and ceramics is often used for a chip package substrate or the like.
Since adhesion of the above members usually requires heat resistance, an epoxy polymer organic adhesive, a frit containing lead glass, alumina, and a heat resistant inorganic adhesive mainly composed of silica are used.
The above-mentioned organic adhesive causes a carbonization phenomenon at a high temperature of 250 ° C. or higher, resulting in a decrease in adhesive strength and airtightness. In some cases, the bonding function is degraded.
On the other hand, in the case of an inorganic adhesive, the frit needs to be treated at a high temperature of 400 ° C. or higher, and when the main component is alumina or silica, a gap is generated between the molecules and the vacuum state is increased. Leakage occurred from the bonding surface, and it was difficult to maintain the desired airtight state at 200 ° C. or higher.
When bonding glass and glass, glass and metal, glass and ceramics, or glass having different thermal expansion coefficients, if the thermal expansion coefficients are different, the glass is broken or the adhesion surface peels off.
[0003]
[Problems to be solved by the invention]
Therefore, the object of the present invention is to bond glass and glass, glass and glass having different thermal expansion coefficients, glass and metal or ceramics, maintain heat resistance strength at a high temperature of 300 ° C. or higher, and at a high temperature of 300 ° C. or higher. An adhesive capable of maintaining airtightness and a method for producing the same are provided.
[0004]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the present inventors have found that siloxane compounds having at least a phenyl group as an adhesive between glass and glass, glass and glass having different thermal expansion coefficients, glass and metal, or ceramics. It was found that a heat-resistant adhesive film having a heat treatment temperature of 200 ° C. to 400 ° C. and a heat-resistant adhesive film having a temperature of 300 ° C. or higher can be obtained in a bonding process at a heat treatment temperature of 200 ° C. to 400 ° C.
[0005]
That is, the present invention
(1) An adhesive comprising a silicon resin containing at least phenylheptamethylcyclotetrasiloxane and 2,6-cis-diphenylhexamethylcyclotetrasiloxane.
(2) The adhesive according to claim 1, which is heat-cured at a temperature of 200 ° C to 400 ° C.
(3) In the process of manufacturing the adhesive, at least once, a vacuum heat treatment is performed at a temperature equal to or lower than a temperature at which the adhesive is cured.
(4) The method for producing an adhesive according to claim 3, wherein the vacuum heat treatment is performed at a temperature of 230 ° C. or lower.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
The adhesive used in the present invention uses phenylheptamethylcyclotetrasiloxane, 2,6-cis-diphenylhexamethylcyclotetrasiloxane, and silicon resin as raw materials, dissolved in an organic solvent such as toluene and xylene, The mixture is heated at ˜150 ° C. for 2 to 5 hours to cause condensation reaction while evaporating the solvent, and further subjected to defoaming treatment under reduced pressure in the range of 100 Pa to 1 Pa while evacuating in a vacuum chamber. Adjust to 10000 cps and paste.
[0007]
Moreover, the adhesive agent which apply | coated the said paste-form adhesive smoothly on the Teflon sheet | seat, and made it the sheet form of thickness 500 micrometers is used as a most preferable example. In the present invention, the sheet-like adhesive mainly composed of silicon resin containing phenylheptamethylcyclotetrasiloxane and 2,6-cis-diphenylhexamethylcyclotetrasiloxane is degassed during the defoaming treatment as compared with other adhesives. There is little, and heat resistance is excellent.
[0008]
Furthermore, the paste adhesive is coated on a glass member by a known coating method such as despancer application, dipping, spraying, and screen printing, and is heated to 300 ° C. in the atmosphere while applying a load to cure the adhesive. . The degree of vacuum during the defoaming treatment is preferably about several Pa, but may be several thousand Pa or high vacuum of 10 to 3 Pa or less as long as the pressure is reduced. The temperature is preferably about 120 ° C. from the viewpoint of safety, but may be any temperature at which the adhesive does not cure.
[0009]
【Example】
Hereinafter, the present invention will be described in more detail with reference to preferred examples. However, the present invention is not limited to these examples, and the substitution and design of each element within a range in which the object of the present invention is achieved. This includes changes and changes in process order.
[0010]
[Example 1]
1 g of phenylheptamethylcyclotetrasiloxane and 59 g of silicon resin are dissolved in 40 g of toluene, and the toluene is evaporated while heating to 100 ° C., followed by a condensation reaction for about 2 hours. Next, this reaction product is transferred onto a hot plate 7 in a vacuum chamber 6 shown in FIG. 4 and evacuated while the hot plate 7 is heated. Defoaming is performed for 10 minutes at a vacuum degree of about 100 Pa in the vacuum chamber 6 and a temperature of 140 ° C. of the hot plate 7. Next, while the hot plate 7 was cooled, the atmosphere was returned to the atmosphere to obtain a paste adhesive having a viscosity of several hundred cps. The reaction product was adjusted to a viscosity of about 200 cps to obtain the adhesive of the present invention.
[0011]
[Example 2]
0.1 g of phenylheptamethylcyclotetrasiloxane, 0.1 g of 2,6-cis-diphenylhexamethylcyclotetrasiloxane and 59.8 g of silicon resin are dissolved in 40 g of toluene, and the toluene is evaporated while heating to 120 ° C. The condensation reaction is performed for 3 hours. Next, this reaction product is transferred onto a hot plate 7 in a vacuum chamber 6 shown in FIG. 4 and evacuated while the hot plate 7 is heated. Defoaming is performed for 60 minutes at a vacuum degree of about 1 Pa in the vacuum chamber 6 and a temperature of 140 ° C. of the hot plate 7. Next, while the hot plate 7 was cooled, the atmosphere was returned to the atmosphere to obtain a paste adhesive having a viscosity of several hundred cps. This paste-like adhesive was applied smoothly on a Teflon sheet, the adhesive was cooled, and returned to room temperature to obtain a sheet-like adhesive having a thickness of 500 μm.
[0012]
[Example 3]
As shown in FIG. 2, a blue plate glass 1 having a 2.8 mm thickness and a φ3 mm hole of 30 mm square and a blue plate glass 2 having a thickness of 2.8 mm and a 30 mm square as an adherend are provided with a thickness of 2.8 mm. A sample for adhesion test was prepared using a soda glass frame 3 having a size of 25 mm and a width of 3 mm. The creation was performed according to the following procedure. As the adhesive, the paste-like adhesive obtained in Example 1 was used.
First, the adhesive 4 obtained in Example 1 was applied to the upper surface of the soda glass frame 3 by softening and applying the adhesive 4 using a dispenser 5 whose periphery was heated to 120 ° C. The blue plate glass frame 3 is overlapped and temporarily bonded. Next, the blue plate glass frame 3 to which the adhesive 4 is temporarily bonded is placed in a baking furnace, a 1 kg weight is placed on it, heated to 300 ° C., and the adhesive is cured and bonded. After cooling, the adhesive 4 is softened and applied to the upper surface of the soda glass frame 3 using a dispenser 5 heated to 120 ° C. in the same process, the soda glass 2 is adhered, and evacuated as a sample for a leak test. A possible chamber 8 was created.
As a result of leak check by connecting the chamber 8 as a leakage test sample to a helium leak detector (Nippon Anelva product) at room temperature and blowing helium gas around the chamber 8, a vacuum tightness below the detection limit was confirmed. .
Furthermore, after this leak test sample was heated to 300 ° C., a leak check was performed again at room temperature. As a result, vacuum tightness below the detection limit could be confirmed as before 300 ° C. heating, and it was confirmed that it was excellent at 300 ° C. It was done.
[0013]
[Example 4]
As the adherend, a 2.8 mm thick, 30 mm square blue plate glass with a hole of φ3 mm and a 2 mm thick, 30 mm square aluminum metal sheet, a 1 mm thick, 20 mm outer dimension, 3 mm wide ceramic ceramic made of alumina. Leak test in the same manner as in Example 3 except that a frame was used and the sheet-like adhesive obtained in Example 2 was cut to about 1 mm as the adhesive, and a clip was used instead of the weight. A sample was prepared.
When this leak test sample was leak checked with a helium leak detector at room temperature in the same manner as in Example 3, a vacuum tightness below the detection limit could be confirmed.
Further, this leakage test sample was heated to 350 ° C., but the sample was not cracked. When the leak check was performed again, it was confirmed that the vacuum tightness was below the detection limit, which was not different from that before heating at 350 ° C. As a result, the adhesion between the ceramic sheet made of alumina and the metal sheet made of Al, which has a different thermal expansion coefficient from that of the blue plate glass, was excellent.
[0014]
[Comparative Example 1]
A leakage test sample similar to that in Example 4 was prepared. However, in this comparative example 1, a glass frit was used as an adhesive, and a process of bonding at a temperature of 410 ° C. was performed.
When the obtained leak test sample was leak checked with a helium leak detector at room temperature in the same manner as in Example 1, a vacuum tightness below the detection limit could be confirmed. Next, the sample was heated to 350 ° C. while connected to a helium leak detector, but a large leak occurred at around 340 ° C. Further, even when cooled to room temperature, the leak did not disappear and the vacuum tightness at 350 ° C. was not satisfactory.
[0015]
[Comparative Example 2]
A leakage test sample similar to that in Example 1 was prepared. However, in the present comparative example 2, a polysulfone adhesive (trade name; product of Staystick 301 Techno Alpha Co., Ltd.) was used as an adhesive. The glass member was coated in an arbitrary shape by a dispenser coating method, defoamed, the solvent was evaporated at 150 ° C., and then a heat treatment temperature of 300 ° C. was used.
When a leak check was performed with a helium leak detector at room temperature in the same manner as in Example 1, vacuum tightness below the detection limit could be confirmed.
Further, heating was attempted up to 350 ° C. with the sample connected to a helium leak detector, but a large leak occurred at around 300 ° C. Even when cooled to room temperature, this leak did not disappear and the vacuum tightness at 350 ° C. was not satisfactory.
[0016]
【The invention's effect】
The adhesive of the present invention is extremely excellent in adhesion at a high temperature of 300 ° C. or higher, such as glass and glass, glass and metal, and glass and ceramics having different thermal expansion coefficients. Moreover, since it is excellent in airtight leakage even at a high temperature of 350 ° C., it is also useful as an airtight member exposed to high temperatures.
[0017]
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of a test chamber.
FIG. 2 is a cross-sectional view taken along the line AA in FIG.
FIG. 3 is a plan view showing an application state of an adhesive by a dispenser.
FIG. 4 is a cross-sectional view showing a defoamed and bonded state in a vacuum chamber.
5 is a cross-sectional view showing a leak detector test state of the leak test chamber obtained in Example 1. FIG.
[Explanation of symbols]
1 Blue plate glass with holes 2 Blue plate glass 3 Blue plate glass frame 4 Adhesive 5 Dispenser 6 Vacuum chamber 7 Hot plate 8 Leak test chamber

Claims (6)

An adhesive comprising heating a mixture containing at least phenylheptamethylcyclotetrasiloxane , 2,6-cis-diphenylhexamethylcyclotetrasiloxane, and silicon resin. The adhesive according to claim 1, wherein the heating temperature is 60 to 150 ° C. The adhesive according to claim 1 or 2, which is in a paste form. The adhesive according to any one of claims 1-3, characterized that you are thermally cured at a temperature of 200 ° C. to 400 ° C.. In the step of producing the adhesive according to any one of claims 1 to 4, after heating a mixture containing at least phenylheptamethylcyclotetrasiloxane, 2,6-cis-diphenylhexamethylcyclotetrasiloxane and silicon resin, At least once, the manufacturing method of the adhesive characterized by performing a vacuum heat treatment below the temperature which the said adhesive hardens | cures. Vacuum heat treatment method of the adhesive according to claim 5, characterized in that at 230 ° C. or lower.

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