JP2000119029A - Heating of glass substrate for forming gap and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly heat a glass substrate change the heating temperature and heat-up speed and heat the substrate with a high energy efficiency by heating the lower part of a substrate holding plate carrying a glass substrate temporarily joined thereto with a thermosetting resin at a temperature for softening the resin, then bringing a hot plate heated at a high temperature into close contact therewith, heating the resin and curing the resin. SOLUTION: A step for softening a resin is carried out by heating the resin with infrared radiations and a curing step is performed by heat conduction with a hot plate H. A vacuum pad 10 and a substrate holding plate 5 are kept in a separated state and the surface temperature of the hot plate H is regulated to a temperature for curing the resin. The substrate holding plate 5 is lowered and made to communicate with the vacuum pad 10. The undersurface of the plate 5 is brought into pressure contact with an annular packing 22 in the upper part of a heat shielding cover 21. The resin is then heated to a softening temperature with far infrared radiations from the plate H. A lifting and lowering cylinder 15 is extended to bring the plate H into close contact with the plate 5 to provide a curing temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for applying a thermosetting resin between two glass plates having a transparent electrode disposed on the inner surface thereof, and temporarily pressing the glass substrates to form a uniform gap. The present invention relates to a method and an apparatus for heating a gapped glass substrate, wherein the glass substrate is ejected and heated to heat and cure the thermosetting resin.

[0002]

2. Description of the Related Art Conventionally, as a method of heating a glass substrate having a gap as described above, a method of assembling a gap forming jig having a pressurizing mechanism, placing the jig in a hot air circulating furnace, and heat-curing a thermosetting resin is known. It is publicly known, for example, from Japanese Unexamined Patent Publication No. 10-39319. On the other hand, from the user who manufactures the liquid crystal cell, the heating of the glass substrate can be performed 1) The entire surface of the glass substrate can be heated at a uniform temperature, 2) The heating temperature and the heating rate can be changed according to the characteristics of the thermosetting resin. And so on.

[0003]

However, in order to meet the needs of the user with the above-described heating method using a hot-air circulating furnace, it is necessary to equip an expensive temperature controller and the mechanism of the apparatus becomes complicated. There was a problem that the price became high. In addition, in the heating with the hot-air circulation furnace, in addition to the gap setting jig and the glass substrate, it is necessary to heat the furnace components, the furnace atmosphere, and other extraneous materials. There was also a problem that energy efficiency could not be improved because the object had to be cooled. The present invention has been made in view of the above-mentioned problems, and is capable of heating the entire surface of a glass substrate at a uniform temperature, changing a heating temperature and a heating rate, and inexpensive gapping glass capable of heating with high energy efficiency. It is an object of the present invention to provide a method and an apparatus for heating a substrate.

[0004]

In order to achieve the above object, a method for heating a glass substrate with a gap according to the present invention comprises the steps of: heating a lower portion of a substrate holding plate on which a glass substrate temporarily bonded by a thermosetting resin is placed; A resin softening step in which the thermosetting resin is heated by far-infrared radiation at a temperature at which the thermosetting resin softens, and a hot plate heated to a high temperature at which the thermosetting resin is hardened to adhere to the lower surface of the substrate holding plate. And a resin curing step of heating by heat conduction.

[0005] In the heating apparatus of the present invention, a lifting cylinder is provided below a vertically movable support for supporting a substrate holding plate on which a glass substrate temporarily joined by a thermosetting resin is placed. A rubber heater divided into a central zone and an outer zone and having a heat insulating material adhered to the lower surface is fixed to the end of the piston rod of the elevating cylinder, and the upper surface of the rubber heater has a smooth surface. A thermocouple for forming a hot plate as a whole by bonding a heating plate in which ceramics are welded to the surface of a stainless plate or an aluminum plate, and detecting respective temperatures at positions corresponding to the central zone and the outer zone of the heating plate And the thermocouples are electrically connected to the rubber heater via a temperature controller. Than it is.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. In FIG. 1, cylinders 3 and 3 are attached to the center of the inner surface of a box-shaped frame 1 via brackets 2 and 2 with brackets 2 and 2 facing upward. The bodies 4, 4 are mounted facing each other. The cross section
Both ends of a substrate holding plate 5 on which a glass substrate P temporarily aligned on the upper surface is placed are supported on the L-shaped supports 4, 4. Further, on the upper part of the substrate holding plate 5, a pressing body 6 whose central part is formed of a pressing sheet and whose peripheral part is formed of a frame is placed.
Is placed.

A plurality of through holes 8, 8 are provided at positions on the substrate holding plate 5 corresponding to the frame portion of the pressing body 6.
A vacuum pad 10, which is always pushed upward by springs 9, 9, is provided below the through holes 8, 8.
10 is pressed. The vacuum pads 10, 1
0 is connected to a vacuum pump 12 having a pressure regulator, a pressure sensor, and the like via the air hoses 11, 11, and the air hoses 11, 11, the vacuum pad 10,
Attachment pipes 13, 13 and bracket 14,
14 is fixed to the inner surface of the box-shaped frame 1.

Further, an elevating cylinder 15 is provided at the inner bottom of the box-shaped frame 1 (an intermediate position between the supports 4 and 4).
At the tip of the piston rod of the elevating cylinder 15, a central portion is divided into a central zone A and a peripheral portion is divided into an outer zone B (see a plan view portion in FIG. 2).
A rubber heater 16 is fixed to a lower surface of the rubber heater 16 by attaching a heat insulating plate 17 thereto. On the upper surface of the rubber heater 16, a heating plate 18 in which ceramics are welded to the surface of a stainless steel plate or an aluminum plate whose surface is smoothed is bonded. That is, the lower surface of the rubber heater 16 is the heat insulating plate 11,
The hot plate H has a sandwich structure with the upper surface sandwiched between the heating plates 18.

The rubber heater 16 in the heating plate 18
Thermocouples 19A and 19B are inserted from the heat insulating plate 17 side at positions corresponding to the central zone A and the outer zone B, respectively, and the thermocouples 19A and 19B are connected to the temperature controllers 20A and 20B.
OB is electrically connected to the center zone A and the outer zone B of the rubber heater 16. (See FIG. 2) Therefore, when the temperature detected by the thermocouples 19A, 19B is not the target temperature, the temperature controller 20A,
20B is operated to adjust the temperature of each of the zones A and B of the rubber heater 16. Further, the upper portion of the lift cylinder 15 surrounds the lift cylinder 15 and the hot plate H and has an opening 21 at the upper end thereof.
A heat shield cover 21 in which A is at the same level as the rising end of the heating plate 18 is attached. An annular packing 22 is attached to the upper part of the periphery of the opening 21A of the heat shield cover 21.

Next, the operation of the above configuration will be described with reference to FIG. FIG. 3A shows a state in which the cylinders 3, 3 are extended and the supports 4, 4 are raised, and the substrate holding plate 5, the glass substrate P
(See FIG. 1), a state in which the pressing body 6 and the heat shield plate 7 are placed, and the vacuum pads 10, 10 and the substrate holding plate 5 are in a state of being separated. At this time, the surface temperature of the hot plate H is previously set by the thermocouples 19A and 19B and the temperature controllers 20A and 20B.
Is adjusted so that the temperature of the center zone A and the outer zone B becomes 160 ° C. Next, the cylinders 3 and 3 are contracted to lower the substrate holding plate 5 and lower the substrate holding plate 5.
The through holes 8, 8 communicate with the vacuum pads 10, 10 and the springs 9, 9 are depressed to press the lower surface of the substrate holding plate 5 against the annular packing 22 above the opening 21A of the heat shield cover 21 and stop. The state is as shown in FIG.

In this state, the vacuum pump 12 shown in FIG. 1 is operated to gap the glass substrate P through the vacuum pads 10, 10, and the like. The glass substrate P is heated. At this time, the heating target temperature (softening temperature of the thermosetting resin) of the glass substrate P is set to 110 ° C., and the surface temperature of the hot plate H is set to 160 ° C., which is the curing temperature of the thermosetting resin.
When set to ° C., the distance between the upper surface of the hot plate H and the lower surface of the substrate holding plate 5 needs to be about 20 mm. Radiation of far-infrared rays is performed in a closed chamber formed by the elevating cylinder 15, the heat shield cover 21, and the substrate holding plate 5, so that uniform radiation heating is performed without being affected by outside air.

When the above-described heating by the far-infrared radiation is performed for a certain period of time, the elevating cylinder 15 is extended to bring the upper surface of the hot plate H into close contact with the lower surface of the substrate holding plate 5 (the state of FIG. 3 (3)). Thereby, the substrate holding plate 5
Further, the glass substrate P (see FIG. 1) is heated by heat conduction from the hot plate H. Since the hot plate H at this time is heated to 160 ° C., which is the resin curing temperature of the thermosetting resin, the glass substrate P is also heated to 160 ° C. By maintaining this state for a predetermined time, the thermosetting resin of the glass substrate P is cured, and the gap is completed. In this way, uniform pressurization by the vacuum action of the vacuum pump 12 and heat hardening of the resin by the hot plate H are performed, and when the gap is completed, the vacuum action by the vacuum pump 12 is shut off, and the elevating cylinder 15 is contracted. At the same time, the cylinders 3 and 3 are extended to return to the state shown in FIG. 3 (1), the substrate holding plate 5 and the like are removed, and preparation for the next gap setting is made.

In the above embodiment, the hot plate H is surrounded by the heat shield cover 21. However, the heat shield cover 21 may be omitted in a place where the influence of the outside air is small. Further, in the above-described embodiment, an example is shown in which the glass substrate P is vacuum-pressed by the pressurizing member 6 whose central portion is formed of a pressing sheet material and whose peripheral portion is formed of a frame. May be used as long as it can perform vacuum pressurization in cooperation with the substrate holding plate 5.

[0014]

According to the present invention, as is apparent from the above description, the substrate holding plate is heated by far-infrared radiation while the preliminarily aligned glass substrate is set on the substrate holding plate so that a gap can be formed. After softening the thermosetting resin, the heated hot plate is brought into close contact with the substrate holding plate and heated by heat conduction to cure the thermosetting resin, so that the device structure is simplified and The glass substrate can be uniformly heated without using an expensive temperature controller, and the heating temperature and the temperature rising speed can be changed by adding a simple temperature control mechanism. The effect of the heating energy is remarkable. For example, there is no waste in heating other members as in the hot air circulation furnace, and high-energy efficiency heating can be performed.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view showing an embodiment of the present invention.

FIG. 2 is a development explanatory view showing a heating mechanism of a hot plate.

FIG. 3 is a step-by-step process diagram of a main part showing a state of gap setting of a glass substrate.

[Explanation of symbols]

 Reference Signs List 4 support 5 substrate holding plate 15 elevating cylinder 16 rubber heater 17 heat insulating plate 18 heating plate 19A 19B thermocouple 20A 20B temperature controller 21 heat shield cover H hot plate P glass substrate

Claims (4)

[Claims] 1. A resin softening step of heating a lower portion of a substrate holding plate on which a glass substrate temporarily joined by a thermosetting resin is mounted by far-infrared radiation for a certain time at a temperature at which the thermosetting resin softens; Heating the gapped glass substrate, comprising: a resin curing step in which a hot plate heated to a high temperature at which the thermosetting resin is cured is brought into close contact with the lower surface of the substrate holding plate and heated by heat conduction. Method. 2. The method according to claim 1, wherein the far-infrared radiation is emitted by the hot plate spaced from the substrate holding plate. 3. An elevating cylinder 15 is disposed below a vertically movable support member 4 supporting a substrate holding plate 5 on which a glass substrate P provisionally joined by a thermosetting resin is placed, and At the tip of the piston rod of the lift cylinder 15,
A rubber heater 16 which is divided into a center zone A and an outer zone B and has a heat insulating material 17 adhered to the lower surface is fixed to the lower surface, and a ceramic plate is formed on the upper surface of the rubber heater 16 on a stainless steel plate or an aluminum plate having a smooth surface. The heating plate 18 on which the hot plate H is welded is bonded as a whole.
The thermocouples 19A, 19B for detecting the respective temperatures are inserted into the heating plate 18 at positions corresponding to the central zone A and the outer zone B from the heat insulating material 17 side, and the thermocouples 19A, 19B Temperature controllers 20A, 20B
A heating device for a glass substrate having a gap, wherein the heating device is electrically connected to the rubber heater 16 through a gap. 4. A heat shield cover 21 surrounding the elevating cylinder 15 and the hot plate H and having an upper opening 21A at the same level as the rising end of the heating plate 18 is provided. 3. The heating device for a glass substrate with a gap according to 3.