JPH06298539A - Bonding of glass material - Google Patents

Abstract

PURPOSE:To provide a method for adhesively bonding glass materials with each other without using an adhesive material and to realize the bonding of glass materials without lowering the transparency. CONSTITUTION:The bonding faces of glass materials are mirror-polished and washed with cleaning water. The wet glass materials are closely contacted with each other, dried at 40-90 deg.C, preheated at 100-150 deg.C and heat-treated at >=400 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass material adhering method for adhering a glass material such as quartz glass without using an adhesive.

[0002]

2. Description of the Related Art Conventionally, a method of using an adhesive has been known as a method of bonding glass materials such as quartz glass to each other. To bond glass materials to each other using an adhesive material, crush the adhesive with a milkbag, sandwich the adhesive between the glass materials, and heat at a temperature of 700 ° C or higher to bond the adhesive surfaces. The adhesive is melted to bond the glass materials together.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide an adhesive method for adhering glass materials to each other without using an adhesive material, and to realize adhesion in which the transparency of the adhesive surface does not decrease.

[0004]

In order to solve the above-mentioned problems, a method for adhering glass materials according to the present invention is a method in which the adhering surfaces of glass materials are polished and mirror-finished, followed by washing with washing water. After making the adhesive surfaces of the glass materials wetted with each other adhere to each other, it is dried at a temperature of 40 to 90 ° C., and 100 to 1
After preheating at a temperature of 50 ° C, heat treatment is performed at a temperature of 400 ° C or higher. It is preferable that the washing water contains 30 mg / l or more of an alkali metal salt.

[0005]

The exact bonding mechanism of the bonding method of the present invention has not been clarified yet. However, from the experimental results that the bonding surfaces of the mirror-finished glass materials adhere to each other under certain conditions, the components and impurities contained in tap water, pure water, etc.
Also, it is considered that a thin adhesive film serving as an adhesion medium is formed on the adhesive surface by heating the additive chemicals, and the adhesive surfaces of the glass materials adhere to each other via the adhesive film.

[0006]

As described above, according to the present invention, the mirror-finished glass materials are brought into close contact with each other through the cleaning water of a specific component without using an adhesive, and dried and heated to adhere. It can be bonded without lowering the transparency of the bonding surface, and can be used for the purpose where transparency is important. For example, it becomes possible to form a complicated optical element by bonding a plurality of optical components having a simple structure, and the substantial effect is large. Further, since the bonding is not performed through the adhesive, the adhesive film is not deteriorated and the durability is improved. Further, it can be used for glass materials other than quartz glass.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The bonding method of the present invention can bond soda glass or potassium glass in addition to bonding quartz glass. The following description will be made on the case of bonding quartz plates to each other.

The bonding method of the present invention includes a mirror finishing step of mirror-finishing the bonding surface of the quartz plate, a cleaning step of cleaning the quartz plate with cleaning water, and a drying process in which the cleaned bonding surfaces of the quartz plates are brought into close contact with each other and heated and dried. And a heating step of heating the quartz plate to be in close contact.

In the mirror finishing step, the adhered surface of the quartz plate to be adhered is polished and polished to a mirror finish of, for example, about 100 Å. In addition, it is necessary to consider the waviness of the adhesive surface, and it is necessary to maintain the accuracy of each unevenness to 0.5 μm or less.

In the washing step, the mirror-finished quartz plate is washed with tap water, pure water, or washing water obtained by adding an additive chemical to these water, and impurities attached to the quartz plate are washed away at the same time. Cleaning water is attached to the surface of the quartz plate. The components of the washing water are important factors that influence the adhesion result. The components of the cleaning water used for the adhesion test and the adhesion results are summarized in Table 1. The components of tap water and pure water are shown in Table 2.

[0011]

[Table 1]

[0012]

[Table 2] The quartz plates that have been washed with the washing water are adhered to each other by adhering the adhering surfaces to each other in a wet state. Then, the surfaces of the bonded quartz plates are thoroughly wiped, and the water in the bonded surface is naturally dried for about 30 minutes.

The drying process is performed in two stages.
First, a quartz plate bonded by a hot plate is dried at 60 ° C. for 1 hour, and then at 120 ° C. for 1 hour.
Allow to dry for 20 minutes. The drying process is preferably performed stepwise while controlling the temperature and the heating time as described above. The reason why the quartz plate is dried in 60 ° / 60 minutes and 120 ° C / 120 minutes as described above is as follows. In the above-mentioned bonding method, two glass sheets are stuck together with water, and then heated at 600 ° C. to be bonded as described later. If the water is not sufficiently dehydrated before being heated to 600 ° C, water will become steam during heating to 600 ° C. The two sheets of glass stuck together by this water vapor pressure are peeled off before they are bonded. 60 ° C ・ 60 minutes and 120 ° C
・ 120 minute heating is equivalent to dehydration processing work,
It was gained by repeating experience and numerous tests. The reason is 1. Most of the water is evaporated at 60 ° C where it hardly boils when heated with a heater. 2. The temperature transmitted to the water remaining on the adhesive surface is 100 ° C
The temperature was higher than 100 ° C. and not higher than 100 ° C., and the temperature was 120 ° C. However, the temperature may change depending on the thickness of the work, the thermal conductivity and the heater used. However, if it is too high, it will come off during dehydration. Dehydration at a preheating temperature of 150 ° C or higher often causes peeling.

The heating step is a step of adhering the dried quartz plate by heating at a relatively high temperature as described above, and is gradually heated in an electric furnace from room temperature to 600 ° C. at a constant temperature rising rate, Heat as it is for a predetermined time. The quartz plate after the heating process is naturally cooled in the electric furnace. still,
The rate of temperature rise during heating is controlled to 5 ° C. per minute using a temperature controller. The heating temperature and the heating time are important factors that influence the adhesion result together with the components of the washing water described above. The test results for each condition are summarized in Table 3.

[0015]

[Table 3] The quartz plate bonded in the above process has a very high transparency on the bonding surface, and it looks as if the bonded quartz plate is made of one piece of quartz. In the bonding method of the present application, the transparency of the bonded glass material bonding surface can be maintained high, and a plurality of glass materials can be bonded in the same manner as a single glass material, and thus is widely applied to the bonding of optical components and the like. It is possible.

The applicant of the present application has been able to clarify the bonding condition of the quartz glass as a result of conducting many experiments as shown in Tables 4 and 5 for completing the bonding method of the present invention.

[0017]

[Table 4]

[0018]

[Table 5]

The essential points of the adhesion conditions obtained by the experiment will be listed below.

1) Heating conditions 1-1. Since the bonding method of the present invention performs bonding by heating, the combination conditions of heating temperature and heating time for which quartz does not deform its shape and the bonding surface can be bonded evenly are known. There is a need. As a result of the test, it was found that the temperature condition was at least 400 ° C. for 30 minutes. In addition, when the temperature was 600 ° C. or higher, heating was carried out for 30 minutes, and then the entire surface adhesion was obtained.

1-2. As a result of conducting a test under a wide variety of condition settings, it was confirmed that partial adhesion was possible even at a low temperature of 180 ° C. for 2 hours.

2) Conditions for washing water 2-1. Quartz can be bonded with tap water. Table 2 shows the results of water quality analysis of tap water.

2-2. Does not adhere even when HCl, HNO ₃ or the like is placed in pure water.

2-3. Reagents containing sodium can adhere.
This is probably because sodium metasilicate was formed on the adhesive surface. However, if the amount of sodium metasilicate contained in pure water is more than necessary, adhesion cannot be achieved.

2-4. CaCl ₂ or MgCl ₂ against pure water
Partly adheres by adding. It is considered that this is due to the influence of Ca or Mg or that impurities were mixed in during the test.

Further, when a 20 mm square quartz block was bonded with tap water, only the central area having a diameter of 10 mm was bonded. When the adhesive surface of the block was measured, it was considered that there was undulation of 2.5 μm on the surface and a gap was formed on the outer periphery of the convex portion, and the block was not bonded. From this, it is considered that the waviness of the adhesive surface requires an accuracy of 0.5 μm or less.

Claims (2)

[Claims] 1. After polishing the mirror-finished surfaces of the glass materials to be bonded to each other and then washing them with cleaning water to bring the bonding surfaces of the glass materials which have been wet with cleaning water into close contact with each other, and then at a temperature of 40 to 90 ° C. A method for adhering a glass material, which comprises: drying at 40 ° C., preheating at a temperature of 100 to 150 ° C., and then heat-treating at a temperature of 400 ° C. or higher. 2. 30 mg / ml of an alkali metal salt in the wash water
2. The method for adhering a glass material according to claim 1, wherein the glass material is included in the above range.