JP3318301B2 - jig - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jig used for heating a liquid crystal substrate and sealing a liquid crystal display element with the substrate in a process of manufacturing a liquid crystal display panel or the like.

[0002]

2. Description of the Related Art A jig used for heat-treating a liquid crystal substrate is required to have uniformity of heat, suppression of dust, and adhesion during vacuum adsorption and desorption.

[0003] As a graphite-like jig having a uniform temperature and a reduced dust, there is, for example, a graphite jig impregnated with glassy carbon and coated as disclosed in JP-A-5-262510. Here, the heat uniformity at 800 ° C. is high,
In addition, the amount of generated dust is reduced, and solar cells and
It is disclosed that it is suitable for a jig used when a thin film semiconductor element is formed on a substrate surface by a method such as CVD in a manufacturing process of a liquid crystal display panel or the like.

In the process of manufacturing a liquid crystal display panel, the temperature is about 200 ° C. in a process of putting a liquid crystal display element in a cell formed by a substrate and a sealing material and performing baking and sealing. The temperature distribution on the surface of the jig to be formed is required to be within ± 2 ° C. within a plane of 600 × 600 mm.

[0005]

However, the graphite impregnated and coated with glassy carbon disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 5-262510 has excellent heat uniformity at 800 ° C. When the temperature is around 200 ° C., there is a problem that the temperature distribution condition is not satisfied.

Further, the flatness of a liquid crystal display panel is determined by the adhesion between the substrate and the jig for heating the liquid crystal substrate when the liquid crystal display element is sealed in the substrate. However, when graphite is impregnated with glassy carbon and coated, the pores existing in the graphite cannot be sufficiently sealed, and therefore, when the substrate is vacuum-adsorbed to the jig, it does not contact the substrate of the jig. There is also a problem that it leaks from the pores of the surface and it is difficult to sufficiently enhance the adhesion.

In view of the above, the present invention has been made in view of the above-mentioned problems. In a manufacturing process of a liquid crystal display panel, a liquid crystal substrate is subjected to heat treatment, and a liquid crystal display element is put into a cell formed by the substrate and a sealing material. A jig for heat treatment of a liquid crystal substrate, which is used in a process of baking and confining and has a temperature distribution within a plane of 600 × 600 mm within ± 2 ° C. at around 200 ° C. and having improved adhesion to a liquid crystal substrate. The purpose is to provide.

[0008]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have conducted intensive studies, and coated a graphite substrate with a thermosetting resin or impregnated or impregnated with a coating. By stopping the resin in a cured state, it has been found that the surface uniformity at around 200 ° C. can be improved, the gas permeability can be reduced, and the adhesion to the article to be treated can be increased, and the present invention has been completed.

That is, the jig of the present invention is a jig used for heat-treating a liquid crystal substrate, and is made of a cured thermosetting resin and made of graphite coated or impregnated or impregnated. It is. Preferably, the curing treatment is performed at a temperature of 400 ° C. or less. Further, the nitrogen gas permeability at room temperature is 1.0 × 10 ⁻⁸ m ²
/ S is preferred.

The graphite substrate used in the present invention is preferably high-purity isotropic graphite produced by a general production method. In particular,
Bulk density 1.7 to 1.9 g / cm ³ , open porosity of 5 to 20
% Is preferred. If the open porosity is less than 5%,
If the effect of impregnating and coating the thermosetting resin is not sufficiently obtained, and if the open porosity is more than 20%, the amount of the thermosetting resin to be impregnated becomes large and the heat conduction becomes low, so that the surface It is not preferable because the heat uniformity is deteriorated.

Examples of the thermosetting resin that covers, impregnates, or impregnates the graphite substrate include resins such as phenolic resins, epoxy resins, polyimide resins, and polycarbodiimide resins. Here, the term “coating” refers to a state in which a part of the thermosetting resin is impregnated in the graphite base material, and most of the other parts cover the surface of the graphite base material. .
1 mm to 1 mm, and the thickness of the surface layer is 1 μm to 20 μm. Further, impregnation refers to a state in which the thermosetting resin is deeply impregnated inside the graphite base material, and the graphite base material surface is thinly coated, and the impregnation depth into the graphite base material is 0.1 mm to 50 mm.
mm, meaning that the surface layer thickness is 1 μm or less. In addition, impregnation coating refers to a state in which the thermosetting resin is deeply impregnated inside the graphite base material, and the graphite base material surface is thickly coated, and the impregnation depth of the graphite base material is 0.1 mm to 50mm,
This means that the surface layer thickness is 20 μm or less. Here, if the coating thickness on the surface exceeds 20 μm, the properties of the thermosetting resin, which is inferior in thermal properties to graphite, become stronger and the heat uniformity of the surface becomes worse, which is not preferable.

The method of coating, impregnating, or impregnating the thermosetting resin is not particularly limited. For example, a jig made of the graphite material processed into an arbitrary size and shape is heat-cured. Examples of the method include immersion in a conductive resin, impregnation with a thermosetting resin under pressure, and application to an arbitrary surface with a brush or a spray. Then, by appropriately combining these methods, the thermosetting resin is impregnated into the graphite substrate from a depth of 50 mm to a coating thickness of 20 μm on the surface, and the impregnation depth and the coating thickness are adjusted. It becomes possible.

After the thermosetting resin is coated, impregnated or impregnated with a coating, the temperature is 400 ° C. or less, preferably 200 to 400 ° C.
The thermosetting resin is cured at 300 ° C. This is because if the thermosetting resin is completely carbonized, the pores of the graphite base material cannot be completely filled in the carbonization stage due to shrinkage of the thermosetting resin or generation of gas. Therefore, by stopping in a hardened state, gas permeation can be reduced, and gas permeability can be less than 1.0 × 10 ⁻⁸ m ² / s. As a result, when used as a jig, when the liquid crystal substrate to be processed is vacuum-adsorbed, no gas leaks from the pores except at the surface in contact with the liquid crystal substrate. Is improved. Here, the gas permeability is 1.0 × 10 ^-8 m ² / s or more, jigs and the adhesion between the liquid crystal substrate is deteriorated, the gas permeability 1.0 × 10 ^-8 m ² / S, preferably 1.0 × 10
It is preferably at most ^-9 m ² / s.

Further, since the thermosetting resin has a heat retaining property, the heat retaining property can be utilized by stopping at a curing stage without completely carbonizing the resin, thereby improving the uniformity of the surface. be able to.

[0015]

The present invention will be described more specifically with reference to the following examples. Example 1 An isotropic graphite material having a bulk density of 1.8 g / cm ³ was processed into 600 × 600 × 35 mm, immersed in a polycarbodiimide resin solution (manufactured by Nisshinbo Co., Ltd.) for 1 hour, and Impregnated with a polycarbodiimide resin solution, and then
A hardening treatment was performed at 50 ° C. to obtain a specimen. The temperature distribution of the surface of the specimen was measured at 200 ° C. in the air, and the center and the end of the specimen were measured with a contact thermocouple at the surface. In addition, the liquid crystal substrate was vacuum-sucked through the specimen, and the adhesion at that time was determined.
Further, a sample of φ30 × 10 mm was cut out for measuring gas permeability, and gas permeability was measured. Similarly, 50 ×
A sample of 50 × 10 mm was cut out, and the number of fine particles having a size of 5 μm or more was measured by a method of measuring fine particles in liquid, and the amount was defined as dust generation.

Example 2 An isotropic graphite material having a bulk density of 1.8 g / cm ³ was processed into 600 × 600 × 35 mm and immersed in a polycarbodiimide resin solution (manufactured by Nisshinbo Co., Ltd.) for 1 hour. After impregnating the graphite material with the polycarbodiimide resin liquid, it was applied to the surface by spraying, and then subjected to a curing treatment at 250 ° C. to obtain a specimen. Thereafter, in the same manner as in Example 1, the temperature distribution on the surface, the adhesion to the liquid crystal substrate, the gas permeability, and the amount of generated dust were determined.

Example 3 An isotropic graphite material having a bulk density of 1.8 g / cm ³ was processed into 600 × 600 × 35 mm and placed in a phenol resin solution (Lignite Co., Ltd.) for 1 hour.
It was immersed, a graphite material was impregnated with a phenol resin solution, and then a curing treatment was performed at 250 ° C. to obtain a specimen. Thereafter, in the same manner as in Example 1, the temperature distribution on the surface, the adhesion to the liquid crystal substrate, the gas permeability, and the amount of generated dust were determined.

Example 4 An isotropic graphite material having a bulk density of 1.8 g / cm ³ was processed into 600 × 600 × 35 mm and placed in a phenol resin solution (Lignite Co., Ltd.) for 1 hour.
After immersion, the graphite material was impregnated with a phenolic resin solution, applied to the surface by spraying, and then subjected to a curing treatment at 250 ° C. to obtain a specimen. Thereafter, in the same manner as in Example 1, the temperature distribution on the surface, the adhesion to the liquid crystal substrate, the gas permeability, and the amount of generated dust were determined.

Example 5 An isotropic graphite material having a bulk density of 1.8 g / cm ³ was processed into 600 × 600 × 35 mm and immersed in a polycarbodiimide resin solution (manufactured by Nisshinbo Co., Ltd.) for 1 hour. A graphite material was impregnated with a polycarbodiimide resin solution, and then subjected to a curing treatment at 400 ° C. to obtain a specimen. Then, in the same manner as in Example 1, the surface temperature distribution,
The adhesion to the liquid crystal substrate, the gas permeability, and the amount of dust generated were determined.

Example 6 An isotropic graphite material having a bulk density of 1.8 g / cm ³ was processed into 600 × 600 × 35 mm and placed in a phenol resin solution (Lignite Co., Ltd.) for 1 hour.
It was immersed, a graphite material was impregnated with a phenol resin solution, and then a curing treatment was performed at 350 ° C. to obtain a test sample. Thereafter, in the same manner as in Example 1, the temperature distribution on the surface, the adhesion to the liquid crystal substrate, the gas permeability, and the amount of generated dust were determined.

(Comparative Example 1) An isotropic graphite material having a bulk density of 1.8 g / cm ³ was processed into 600 × 600 × 35 mm and placed in a phenol resin solution (Lignite Co., Ltd.) for 1 hour.
The graphite material was immersed, and the graphite material was impregnated with the phenol resin solution. Thereafter, a hardening treatment was performed at 250 ° C., followed by a baking treatment at 800 ° C. to obtain a specimen. Then, as in Example 1,
The surface temperature distribution, adhesion to the liquid crystal substrate, gas permeability, and dust generation were determined.

Comparative Example 2 An isotropic graphite material having a bulk density of 1.8 g / cm ³ was processed into a sample of 600 × 600 × 35 mm to obtain a specimen. Thereafter, in the same manner as in Example 1, the temperature distribution on the surface, the adhesion to the liquid crystal substrate, the gas permeability, and the amount of generated dust were determined.

Incidentally, the gas permeability was measured using the fine gas shown in FIG.
It was determined by a transmittance measuring device. First, sample 3
And set the air inside the chamber A1 low.
After evacuating with a tally pump 10A, filling with nitrogen gas
You. On the other hand, the rotary pump 10B
Reduce pressure until equilibrium is reached. Rotary pump 1
With the stop of 0A, the gas in the chamber A1
Pressure through chamber-B2
Start to rise. The pressure in the chamber B2 is a manometer 5
Measure with Pressure P in chamber A1_A(Pa)
Pressure P in chamber B2_B(Pa) is very small
At the initial time t (s), the pressure P in the chamber B2
_B(Pa) ascending speed (ΔP_B/ △ t). Cha
The volume in the member B2 is V_B(Cm^Three) And the ventilation volume Q
= V_B(ΔP_B/ △ t). Pressure in chamber B2
As long as the change in force rise can be considered linear, the airflow
Q is given by the following equation. Q = (P_B2−P_B1) V_B/ (T_Two-T₁) Where P_B1Is the time t₁Of chamber B2 at
(Pa), P_B2Is the time t _TwoOf chamber B2 at
Force (Pa), V_BIs the volume of chamber B (cm^Three)
You. By applying the Q obtained here to the following equation, the gas permeability K
Ask. K = QL / ΔPA where K is gas permeability (cm^Two/ S), Q is the ventilation volume
(Pa · cm^Three/ S), ΔP is the pressure difference (P
a), L is sample thickness (cm), A is gas permeation area (c)
m^Two).

Specifically, the measurement is performed as follows. The sample 3 is set in the apparatus using a jig having a packing (O-ring) 4. Next, after evacuating the air in the chamber A1, nitrogen or helium as a measurement gas is supplied to the chamber A1.
And a predetermined pressure P _A (Pa). At this time,
It is confirmed that the pressure in the chamber B2 reaches the equilibrium pressure P _B (Pa). Degassing is continued for approximately 5 to 24 hours even when equilibrium is reached. This is to sufficiently perform degassing from the inside of the chamber or the sample, and to reduce errors in determination due to degassing from the inside of the chamber or the sample during measurement. The vacuum valve between the rotary pump 10B and the chamber B is closed, and the measurement is started. Since the pressure P _B (Pa) in the chamber B2 starts to increase due to the gas permeating through the sample 3 from the chamber A1, this is measured by the manometer 5 and recorded on the recorder as a function of the time t. The volume V _{B of the} chamber B is 13 cm ³ .
When measuring a material with high gas permeability, chamber B2
Since it is necessary to increase the pressure rise of the sample and increase the reliability of the measurement, a spare tank 6 having a capacity of 1000 cm ³ is used. The measurement conditions are as follows. Dummy samples: Stainless (V _B = 1013cm ³⁾ Sample Dimensions: 0 30 × 1 mm using gas: Nitrogen (△ P = 300kPa)

As described above, Examples 1 to 6 and Comparative Examples 1 and 2
Table 1 collectively shows the measurement results of the respective characteristic values of the test specimens.

[0026]

[Table 1]

According to Table 1, the test pieces of Examples 1 to 6 which were impregnated with or impregnated with a thermosetting resin and then cured at 400 ° C. or less had a gas permeability of less than 1 × 10 ⁻⁸ m ² / s. Good adhesion to liquid crystal substrate, temperature distribution at 200 ° C is within ± 2 ° C, excellent surface uniformity, small amount of dust, and sufficient requirements as a jig for liquid crystal substrate heat treatment It was satisfied. On the other hand, the completely carbonized sample of Comparative Example 1 was inferior in all of the gas permeability, adhesion, heat uniformity, and dust generation amount to the sample of the present example stopped in a cured state.

[0028]

The present invention is configured as described above.
It is used at the time of heat treatment of a liquid crystal substrate by coating or impregnating or impregnating a graphite substrate with a thermosetting resin, curing at a temperature of 400 ° C. or less, and stopping the thermosetting resin in a cured state. It can be used as a jig, greatly reducing defects when enclosing a liquid crystal display element between liquid crystal substrates, and has a long life as a jig used at that time. This has the effect of significantly reducing manufacturing costs.

[Brief description of the drawings]

FIG. 1 is a schematic view of a minute gas permeability measuring device.

[Explanation of symbols]

 Reference Signs List 1 chamber A 2 chamber B 3 sample 4 packing 5 manometer 6 spare tank 7 pressure gauge 8 Pirani vacuum gauge 9 ionization vacuum gauge 10A, B rotary pump 11 turbo molecular pump 12 gas introduction direction 13 gas exhaust direction

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-262510 (JP, A) JP-A-10-287470 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02F 1/1339 505 G02F 1/13 101 C01B 31/04

Claims (6)

(57) [Claims] 1. A jig used for heat-treating a liquid crystal substrate, the jig being made of graphite coated or impregnated or impregnated with a cured thermosetting resin. 2. Used for heating a liquid crystal substrate.
A jig in which the cured thermosetting resin
Impregnated with a depth of 0.1 mm to 1 mm and a layer thickness of 1 on the surface
Black coated with thermosetting resin coated with μm to 20 μm
A jig made of lead. 3. A method for heating a liquid crystal substrate.
A jig in which the cured thermosetting resin
Impregnated with depth 0.1mm ~ 50mm, surface layer thickness
Graphite impregnated with thermosetting resin coated 1 μm or less
Jig consisting of. 4. Used for heating a liquid crystal substrate.
A jig in which the cured thermosetting resin
Impregnated with depth 0.1mm ~ 50mm, surface layer thickness
20 μm or less coated thermosetting resin impregnated
Jig made of graphite. 5. The jig according to claim 1, wherein said curing treatment is performed at a temperature of 400 ° C. or less. 6. A nitrogen gas permeability at room temperature of 1.0 ×
The jig according to claim 1, wherein the jig is less than 10 ⁻⁸ m ² / s.