JP2002040223A - Holding member for objective body to be heated and heating furnace using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a holding member for the objective body to be heated so as not to leave transfer traces on the objective body to be heated, and to provide a heating furnace. SOLUTION: The holding member is used to hold the objective body to be heated when the objective body is heated by using a heating source, and the holding member has <=2.0 mm2 cross section S1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a color filter for a liquid crystal display (hereinafter referred to as a color filter).
In a manufacturing process such as a manufacturing process, a heat treatment is performed by bringing a substrate close to a hot plate (hereinafter, referred to as an HP).
Particularly, the present invention relates to a member to be heated which is suitably used when used as a proximity pin (hereinafter, referred to as a proxy pin) of a heating furnace and a heating furnace using the same.

[0002]

2. Description of the Related Art In the process of producing a color filter, a photosensitive resin is coated in a laminated state on a positive or negative photosensitive resin colored with a pigment or the like on a substrate, or on a colored non-photosensitive resin. After drying and hardening this in a heating furnace, a method of processing it into a desired pattern by photolithography has become mainstream. In many cases, an overcoat agent is applied to the surface of the substrate after photolithography processing, dried and cured, and the drying and curing steps using a heating furnace occupy an important position in the color filter manufacturing process.

There are various types of heating furnaces, such as an HP system, a hot air oven system, and a vacuum drying system, and are appropriately selected depending on the type and purpose of the resin.

In the HP system, the object to be heated is held directly on a plate heated by an electric heater or the like or on a jig such as a proxy pin installed on the plate, and is mainly heated by radiant heat transfer from the HP. This is a method of heating a heating body.

[0005] The hot-air oven system is a system in which hot air heated by an electric heater or the like is circulated in a heating furnace, and an object to be heated held in the furnace is heated mainly by convection heat transfer.

[0006] The vacuum drying method is a drying method in which an object requiring drying is held in a vacuum chamber and the inside of the chamber is decompressed to promote the evaporation of the solvent.

However, the conventional heating furnace has the following problems.

That is, when the object to be heated is heated in the heating furnace, a transfer mark of the member to be heated is generated in the holding portion for holding the object to be heated in the object to be heated. Was.

[0009] Here, the transfer mark means that the shape of an object approaching or in contact with the object to be heated remains as unevenness that can be visually confirmed on the object to be heated. It appears because a temperature difference occurs in the heated body in other parts.

[0010] The mechanism of generating transfer marks will be described by taking, as an example, a step of heating a resin layer applied on a glass substrate in an HP heating furnace.

In the case of the HP type heating furnace, the proxy pin is directly attached to the HP at a temperature higher than the ambient temperature.
The proxy pin temperature is likely to be higher than the ambient temperature.
Since the object to be heated comes into contact with the proxy pin, which has become hot, a temperature difference occurs in a portion that is in contact with the portion that is not in contact with the proxy pin, and the resin layer that is the object to be heated is locally caused by the temperature difference. Fluid. When the locally flowing resin layer hardens, a film thickness distribution is formed on the uniform film surface, and this film thickness distribution remains as a transfer mark.

In the case of a color filter for a liquid crystal display, for example, when a transfer mark is generated when heating a resin layer colored in red, the transfer mark is displayed in a corresponding portion when displaying a red color on the liquid crystal display, and the entire surface is uniform. There was a problem that red display was not possible.

As measures against transfer marks, Japanese Patent Application Laid-Open No. 8-23643
No. 1 proposes a method of providing a second HP that can be moved up and down, and eliminating a local temperature gradient by bringing the second HP into contact with the entire surface of the substrate that is the object to be heated. However, the provision of the second HP not only increases the cost of the apparatus, but also makes it difficult to keep the HP horizontal and move it up and down in a heating furnace with thermal expansion of the members.

JP-A-8-69962 and JP-A-8-69962
In 279548, at the same time as the measure for removing the proxy pin, a synthetic resin such as a polyimide resin is used as the proxy pin material, and the contact area between the proxy pin and the object to be heated is set to 0.008 to 0.2 mm ² . It proposes that the degree of non-uniformity of the temperature distribution on the substrate surface can be reduced to a level that does not adversely affect the resist sensitivity. However, when the viscosity of the coating liquid is reduced for the purpose of increasing the throughput of the coating apparatus, the flow of the coating liquid due to a local temperature gradient is likely to occur, and the contact area between the proxy pin and the object to be heated only falls within the above range. Did not prevent transfer marks.

[0015]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art, and prevents transfer marks of a member to be heated holding a member to be heated from being formed in the object to be heated. It is an object of the present invention to provide a heated object holding member and a heating furnace that do not cause deterioration in product quality.

[0016]

A method for manufacturing a member to be heated, a heating furnace, and a color filter according to the present invention, which achieves the above objects, is as follows. (1) A holding member for holding the the heated body when heating materials using a heat source, the characterized in that the cross-sectional area S ₁ of the holding member is 2.0 mm ² or less Heated body holding member. (2) The heated member holding member according to (1), wherein the thermal conductivity is 0.25 kcal / m hr ° C or less. (3) The member-to-be-heated holding member according to any one of (1) and (2), wherein the structure is a pipe-like structure. (4) The difference between the outer diameter D and the inner diameter d of the pipe-shaped structure is 0.1 to
The heated object holding member according to the above (3), which is 0.3 mm. (5) The heated member holding member according to any one of (3) to (4), wherein the outer diameter D of the pipe-shaped structure is 4.4 mm or less. (6) The heated member holding member according to any one of (3) to (5), wherein the material forming the pipe-shaped structure is a heat-resistant resin. (7) The heated member holding member according to (6), wherein the heat-resistant resin is a polyimide resin. (8) A heating furnace using the member-to-be-heated held member according to any one of (1) to (7). (9) The heating furnace has a structure in which the object to be heated is heated by passing the object through a gap between a hot plate having a heating source and a reflection plate provided on the opposite side of the hot plate. The heating furnace according to the above (8), characterized in that: (10) The heating furnace according to (9), wherein the heated object holding member is a proxy pin installed on a hot plate. (11) The above-mentioned (8), wherein the structure of the heating furnace is of a so-called hot-air oven type in which hot air heated by a heating source circulates in the chamber to heat a body to be heated in the chamber. The heating furnace as described. (12) The heating furnace according to any of (8) to (11), wherein the object to be heated is a transparent substrate. (13) The heating furnace according to any one of (8) to (11), wherein the object to be heated is a glass substrate. (14) The heating furnace according to any one of (8) to (11), wherein the object to be heated is a substrate for a liquid crystal display. (15) The heating furnace according to any one of (8) to (11), wherein the object to be heated is a color filter. (16) A method for producing a color filter, comprising using the heating furnace according to any one of (8) to (15).

[0017]

Next, a preferred embodiment of the present invention will be described.

Sectional area S of heated member holding member₁Is 2.0
mm^TwoBelow, preferably 1.0 mm ^TwoLess preferred
Or 0.7mm^TwoIt is as follows. Cross-sectional area S₁Is 2.0m
m^TwoIf it is larger than, from the heating source through the heated object holding member
As a result, heat transfer to the contact portion between the heated body holding member and the heated body is prevented.
As a result, transfer marks are formed on the object to be heated. Real
As shown in Examples and Comparative Examples, the cross-sectional area S₁Is 3.1mm^Two
Transfer marks appear, and the cross-sectional area S₁Is 1.0mm^TwoThen thick
Transfer marks appeared only when applied to the film and applied to the thin film
In this case, no transfer mark appeared. Cross-sectional area S₁Is 0.7m
m^TwoIn the following, transfer marks occur at all tested film thickness levels.
Did not show.

The thermal conductivity of the member to be heated is preferably not more than 0.25 kcal / m hr ° C, more preferably not more than 0.20 kcal / mhr ° C, and even more preferably not more than 0.15 kcal / mhr ° C. . If the thermal conductivity is greater than 0.25 kcal / mhr ° C., heat transfer from the heating source to the contact portion between the heated body holding member and the heated body through the heated body holding member increases, and transfer marks are formed on the heated body. It is not preferable because it is caused.

In the present invention, it is preferable that the heated object holding member has a pipe-like structure. Here, the pipe-like structure generally refers to a structure having a hollow structure regardless of a cross-sectional shape of a circle, a triangle, or a polygon. Hereinafter, the present invention will be described in detail with a circular cross section as a representative example.

When the object to be heated has a pipe-like structure, the difference D-d between the outer diameter D and the inner diameter d of the pipe-like structure varies depending on the material and weight of the object to be heated. ~
0.3 mm, more preferably 0.15 to 0.25 mm,
More preferably, it is 0.15 to 0.25 mm. If the above difference D-d is smaller than 0.1 mm, the strength becomes insufficient and it becomes difficult to stably hold the object to be heated. Also the difference D
When −d is larger than 0.3 mm, heat transfer from the heating source to the contact portion between the heated body holding member and the heated body through the heated body holding member increases, so that a transfer mark is generated on the heated body. It is not desirable because it becomes.

As shown in the embodiment, D−d is 0.3 mm
No transfer marks appeared only when applied to a thick film, and no transfer marks appeared when applied to a thin film. D-d is 0.2
When the thickness was equal to or less than mm, no transfer mark appeared at all the film thickness levels tested. However, when D-d was 0.1 mm, damage due to insufficient strength occurred in a part of the heated object holding portion.
That is, if heating a coating film applied to a thin film on a lightweight heating target, D-d may be 0.1 to 0.3 mm,
When the thickness of the coating film is large, the thickness is preferably 0.1 to 0.2 mm. If the object to be heated is a glass substrate, and if the heating of the coating film applied to the glass substrate as a thin film, the difference D−d is set to 0.2 to 0.3 mm in consideration of the strength of the member to be heated. Is good. When a resist film having a wet film thickness of 12 μm or more applied on a glass substrate is heated as in the process of manufacturing a color filter in which the present invention is preferably used, D-
d is preferably 0.15 to 0.25 mm.

The outer diameter D of the pipe-shaped structure varies depending on the material and weight of the object to be heated, but is preferably 4.4 mm.
Below, more preferably 3.2 m or less, still more preferably 2.3 mm or less. If the outer diameter D is larger than 4.4 mm, unless the difference D−d between the outer diameter D and the inner diameter d is reduced,
The cross-sectional area of the pipe-shaped structure cannot be reduced, and the strength of the pipe-shaped structure is insufficient. As mentioned above,
In order to secure the strength of the pipe-like structure, the difference D-d between the outer diameter D and the inner diameter d is preferably set to 0.2 mm or more.
If the outer diameter D is 4.4 mm or less, the difference D−d is 0.3 m.
Even if m, the cross-sectional area S ₁ can be set to 2.0 mm ² or less. If the outer diameter D is 3.2 mm or less, the cross-sectional area S ₁ can be set to a suitable 1.0 mm ² or less even when the difference D−d is 0.2 mm, and the outer diameter D is 2.3 mm or less. if the difference D-d can also be a cross-sectional area S ₁ to a particularly preferred 0.7 mm ² or less as 0.2 mm.

The material for forming the pipe-like structure is not particularly limited as long as the thermal conductivity of the member is within the above-mentioned range, but heat-resistant resins such as polyimide, polyamideimide, polyetheretherketone, and polyphenylenesulfide are used. It is preferably used. Among them, polyimide is excellent in heat resistance and is particularly preferably used.

The heat conductivity of the heat-resistant resin suitably used in the present invention is preferably 0.25 kcal / m hr ° C. or less. The thermal conductivity of the polyimide resin particularly preferably used in the present invention is, for example, "TI-5013" (manufactured by Toray Industries, Inc.) at 0.20 kcal / m hr ° C. Further, as shown in the examples, the thermal conductivity was 0.14 kcal /
m hr ° C (at 75 ° C), 0.15 kcal / m
"Kapton" (hours at 200 ° C)
It was confirmed that the effect of the present invention was obtained by using DuPont.

The method of fixing the pipe-like structure is not particularly limited, but a method of providing a mounting hole having the same diameter as the outer diameter D of the pipe-like structure at a position to be fixed, and directly inserting the mounting hole into the mounting hole,
There is a method of providing a projection having the same diameter as the inner diameter d of the pipe-like structure at a position to be fixed, and inserting the pipe-like structure into the projection,
The method of using the projection includes a method of using a fixed projection, a method of attaching a movable projection by a method proposed in Japanese Patent Application Laid-Open No. H11-263360, and the like, and is appropriately selected.

When a projection having the same diameter as the inner diameter d of the pipe-like structure is provided, the height of the projection is preferably １ ／, more preferably １ ／, more preferably ４ of the height of the pipe-like structure. Is good. If the height of the projection is higher than １ ／ of the height of the pipe-like structure, the effect of the present invention may be impaired because heat is transmitted to the heated object through the projection.

The object-to-be-heated holding member of the present invention is effective when used as a proxy pin of an HP-type heating furnace for curing and drying a resin layer applied on a flat plate. It is particularly effective to use a coated resin layer such as a photosensitive or non-photosensitive color paste or a resist as a proxy pin of an HP type heating furnace for drying and curing.

The HP type heating furnace comprises one or a plurality of HPs. FIG. 1 shows an example of an HP type heating furnace composed of a plurality of HPs. 1 is HP, 2 is reflector, 3
, A proxy pin as a member to be heated, 4 a glass substrate as a member to be heated, 5 a transfer arm, 6 a cooling plate (hereinafter referred to as CP), and 7 a drive system. In the case of being composed of a plurality of HPs, the glass plate 4
After being placed on the upper surface 1 and heated for a specified time, the wafer is transported onto the HP 2 by the transport arm 5 connected to the drive system 7.
Next, after being heated on the HP2 for the specified time,
It is again placed on the HP 3 by the transfer arm 5. Similarly, after being heated by HP3 and HP4, the temperature is lowered to room temperature by CP and carried out of the heating furnace.

In the case of an HP type heating furnace composed of a plurality of sheets,
The proxy pin of the present invention may be used for all or a plurality of selected parts. When used for a part of a plurality of sheets, for example, the proxy pin of the present invention is used for the HP of a portion where the resin layer flowing in an undried state is heated, such as HP1 and HP2 in FIG. It is preferable to use a conventional proxy pin for the portion of the HP that heats the resin layer that has stopped flowing.

When a plurality of proxy pins are provided on one HP, the plurality of proxy pins may be used for all or a part selected in particular. When used for a plurality of parts, the proxy pin of the present invention is used for the proxy pin that holds the portion that becomes the effective portion of the color filter, using a conventional proxy pin that holds the outer peripheral portion that is not the effective portion of the color filter. Good to use.

The height of the proxy pin varies depending on the size of the glass substrate, the type of the resin layer to be heated, the purpose of heating, and the like, but the height of the proxy pin is determined by coating on a 620 × 750 × 0.7 mm ³ glass substrate. When heating the resin layer, the height of the proxy pin is preferably about 5 to 12 mm. If the value is lower than the above value, it may cause a conveyance failure in the case of transporting by the Fonger shuttle method. If the value is higher than the above value, the temperature distribution in the glass substrate becomes undesirably wide.

The material of the HP is not particularly limited, but metals such as aluminum, iron, and copper, alloys of metals, and materials obtained by subjecting metals to surface treatment such as ceramics are preferably used.

An electric heater is preferably used as a heat source for HP.

The heating temperature range of the HP varies depending on the type and purpose of the object to be heated.
The temperature may be selected as appropriate, such as 300 ° C. or room temperature to 350 ° C.

The shape of the HP is not particularly limited, but it is desirable that the surface facing the object to be heated is flat. If it is not flat, there is a concern that the object to be heated cannot be heated uniformly due to the variation in the distance from the HP surface to the object to be heated.

The material of the reflection plate is not particularly limited, but metals such as aluminum, iron and copper, and metal alloys are preferably used.

According to the present invention, the cross-sectional area of the proxy pin,
By defining the material, the heat transfer from the HP as the heating source to the tip of the proxy pin, which is in contact with the object to be heated, is suppressed low, and the difference between the temperature at the tip of the proxy pin and the ambient temperature is reduced. We succeeded in suppressing transfer marks caused by pins.

[0039]

EXAMPLES The present invention will be described based on examples, but the effects of the present invention are not limited by the examples.

Example 1 FIG. 2 is a schematic view of a heating furnace used in tests of an example of the present invention and a comparative example. The heating furnace is composed of one HP. 1 is HP, 2 is HP
Is a reflection plate installed on the opposite side of the reflector. Reference numeral 3 denotes a proxy pin, which is a holding portion for the object to be heated, and is fixed to the HP 1. Reference numeral 4 denotes a glass substrate used as a heating target. The glass substrate is placed on the 3 proxy pins, 1 HP and 2
Is heated between the reflectors.

FIG. 3 is a schematic view of a proxy pin according to an embodiment of the present invention, in which an outer diameter D = 2.1 mm and an inner diameter d =
2.0 mm, cross-sectional area S ₁ = 0.32 mm ² , contact area with glass substrate S ₂ = 0.32 mm ² , and proxy pin height is 10 mm.

As a material of the proxy pin, "Kapton" (manufactured by Du Pont-Toray Co., Ltd.) which is a polyimide resin was used. The thermal conductivity of Kapton is 0.14 kcal / m hr
° C (at 75 ° C).

A photoresist (SRC-100, manufactured by Shipley Far East Co., Ltd.) diluted with propylene glycol monomethyl ether acetate to a solid content of 15% (viscosity: 5 mPa · s) is 620 × 720 ×
It was applied to 0.7 mm ³ non-alkali glass (# 1737, manufactured by Corning Japan KK) using a bar coater, and heated for 10 minutes using the heating furnace shown in FIG. The wet film thickness was set to four levels of 6 μm, 9 μm, 12 μm, and 15 μm, and the set temperature of the HP was 120 ° C.

The heated substrate was visually observed by reflection from a fluorescent lamp. No transfer traces of proxy pins were observed on the heated substrate regardless of the film thickness level, but some of the proxy pins were damaged such as bending.

[Embodiment 2] An outer diameter D is used as a proxy pin.
= 2.2 mm, inner diameter d = 2.0 mm, cross-sectional area S ₁ = 0.
66 mm ² , contact area S ₂ = 0.66 m with glass substrate
A test was performed in the same manner as in Example 1 using m ² and a proxy pin height of 10 mm. The material of the proxy pin is the same as that of the first embodiment.

As a result, no transfer mark of the proxy pin was observed irrespective of the film thickness level, and there was no damage to the proxy pin.

[Embodiment 3] An outer diameter D is used as a proxy pin.
= 2.3 mm, inner diameter d = 2.0 mm, cross-sectional area S ₁ = 1.
0 mm ² , contact area with glass substrate S ₂ = 1.4 m
A test was performed in the same manner as in Example 1 using m ² and a proxy pin height of 10 mm. The material of the proxy pin is the same as that of the first embodiment.

As a result, no transfer marks of proxy pin were observed at the wet film thickness of 6 μm and 9 μm.
When the wet film thickness was 12 μm or 15 μm, transfer marks of proxypin appeared. There was no proxy pin damage.

Comparative Example 1 FIG. 4 is a schematic view of a proxy pin used in a comparative example, having a diameter D = 2.0 mm, a sectional area S ₁ = 3.1 mm ² , and a contact area S ₂ with a glass substrate. = 0.
03 mm ² and the height of the proxy pin is 10 mm. The material constituting the proxy pin has a thermal conductivity of 0.20 kcal / m
A polyimide resin at hr ° C was used.

Using the above proxy pin, a test was performed in the same manner as in Example 1. As a result, at all film thickness levels, transfer marks 8 of proxy pins as shown in FIG.
Was observed. There was no proxy pin damage.

Table 1 summarizes the results of the study in the examples and comparative examples.

[0052]

[Table 1]

[0053]

According to the present invention, it is possible to prevent a transfer mark of a member to be heated holding a member to be heated from being formed in the member to be heated, and to prevent a decrease in product quality due to the transfer mark. The holding member and the heating furnace could be provided.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a heating furnace according to the present invention.

FIG. 2 is a schematic view of a heating furnace used in tests of Examples and Comparative Examples.

FIG. 3 is a schematic view of a proxy pin according to an embodiment of the present invention.

FIG. 4 is a schematic view of a proxy pin which is one of comparative examples of the present invention.

FIG. 5 is a schematic view showing a transfer mark of a proxy pin.

[Explanation of symbols]

 1: HP 2: reflective plate 3: proxy pin 4: glass substrate 5: transfer arm 6: CP 7: drive system 8: transfer mark

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H048 BA11 BB32 BB42 3K092 PP09 PP20 QA05 QB47 RF03 RF09 SS47 SS48 TT40 VV22 VV40 4K055 AA05 HA01 HA11 HA27

Claims (16)

[Claims] 1. A holding member for holding an object to be heated when the object to be heated is heated using a heating source, wherein a cross-sectional area S _{1 of the} holding member is 2.0 mm ² or less. To be heated. 2. The thermal conductivity is 0.25 kcal / m hr.
The heated member holding member according to claim 1, wherein the temperature is not more than ° C. 3. The member to be heated according to claim 1, wherein the structure is a pipe-like structure. 4. The difference between the outer diameter D and the inner diameter d of the pipe-like structure is 0.
The heated object holding member according to claim 3, wherein the length is 1 to 0.3 mm. 5. The member to be heated according to claim 3, wherein an outer diameter D of the pipe-shaped structure is 4.4 mm or less. 6. A member to be heated according to claim 3, wherein the material forming the pipe-like structure is a heat-resistant resin. 7. The member to be heated according to claim 6, wherein the heat-resistant resin is a polyimide resin. 8. A heating furnace using the member-to-be-heated holding member according to claim 1. 9. The heating furnace has a structure in which an object to be heated is heated by passing the object through a gap between a hot plate having a heating source and a reflection plate provided on an opposite side of the hot plate. The heating furnace according to claim 8, wherein: 10. The heating furnace according to claim 9, wherein the heated object holding member is a proximity pin installed on a hot plate. 11. The structure of the heating furnace according to claim 8, wherein the structure of the heating furnace is a hot-air oven type in which the heated air heated by the heating source circulates in the chamber to heat the object to be heated in the chamber. The heating furnace as described. 12. The heating furnace according to claim 8, wherein the object to be heated is a transparent substrate. 13. The heating furnace according to claim 8, wherein the object to be heated is a glass substrate. 14. The heating furnace according to claim 8, wherein the object to be heated is a substrate for a liquid crystal display. 15. The heating furnace according to claim 8, wherein the object to be heated is a color filter for a liquid crystal display. 16. A method for producing a color filter, comprising using the heating furnace according to any one of claims 8 to 15.