KR102365293B1 - Method of manufacturing a flexible device, a flexible device, a flexible device manufacturing apparatus and a resin solution for forming a flexible substrate - Google Patents

Abstract

[Problem] To provide a method for manufacturing a flexible device that is a simple method, has a low manufacturing cost, and allows easy removal of a rigid support from a flexible substrate having a resin layer that can be applied to various resins.
[Solution] A flexible substrate forming process of forming a flexible substrate on a rigid support by applying a resin solution on a rigid support, a functional layer forming process of forming a functional layer on the flexible substrate, and a flexible substrate with the functional layer formed A method for manufacturing a flexible device comprising each step of a support removal step of removing a layer from a hard support together with a functional layer, wherein in the flexible substrate forming step, a resin solution is applied after the hard support is heat-treated. A method of manufacturing a device.

Description

A flexible device manufacturing method, a flexible device, a flexible device manufacturing apparatus, and a resin solution for forming a flexible substrate TECHNICAL FIELD

The present invention relates to a method for manufacturing a flexible device that can easily remove a rigid support from a flexible substrate on which a functional layer is formed, a flexible device manufactured by the manufacturing method, and a flexible device manufacturing apparatus for the manufacturing method.

Electronic devices such as liquid crystal displays, organic EL displays, solar cells, touch panels, and color filters are mainly manufactured using glass as a substrate. An electronic device using a flexible substrate such as plastic instead of the glass substrate is called a so-called flexible device. In the case of manufacturing a flexible display, which is one type of flexible device, it is preferable to utilize the existing manufacturing technology for glass substrates (including manufacturing facilities) in order to suppress an increase in manufacturing cost due to the introduction of new facilities.

An example of a method for manufacturing a flexible display using an existing manufacturing technology is to first mount a flexible substrate on the support using glass as a support, then mount a functional element on the flexible substrate, and conduct a conduction pattern formation, sealing, etc. (hereinafter, collectively referred to as "functional layer formation process"). Next, the flexible substrate and the functional element are peeled off from the support (hereinafter referred to as "support removal process"). To this end, it is important that the glass substrate and the flexible substrate are not peeled off in the functional layer forming process, and that the flexible substrate is peeled off without damaging the flexible substrate itself and the functional element in the support removing process.

In addition, in the manufacturing process of a flexible device, heat processing (200-500 degreeC) and various chemical processing are normally performed with respect to a flexible board|substrate. For this reason, heat resistance and chemical resistance are calculated|required of a flexible board|substrate. Polyimide resin has been studied as a flexible substrate material to meet such a request (refer to Patent Documents 1 to 3). Since this polyimide resin has a low coefficient of linear thermal expansion (CTE) and is relatively easy to control, it is characterized in that it is difficult to cause problems in the use of products and manufacturing processes that may be exposed to high temperatures.

Among these, in Patent Document 1, a flexible device comprising a step of coating and forming a liquid resin composition on a carrier substrate to form a solid resin film, and forming a circuit on the resin film to peel the carrier substrate from the resin film. is disclosed, and there is a disclosure to the effect that the resin film is excellent in peelability from a carrier substrate without causing defects such as peeling in the circuit. However, there is no disclosure about the control of the peel strength between the carrier substrate and the resin film. That is, the difficulty in peeling of the carrier substrate-resin film in the said functional layer formation process is not clear.

Moreover, in patent document 2, the process of forming a polyimide film on a support body, forming a thin film device on it, peeling from a support body, and obtaining a film device is disclosed, The peeling force of the polyimide film from a support body is 0.05 N/cm to 1.55 N/cm are disclosed. In that case, it is not peeling during film device processing, and the effect is disclosed that it is possible to peel quickly after completion|finish of processing. However, resins applicable to this process are limited to those having a benzol skeleton.

Further, in Patent Document 3, a layer to be peeled is formed by forming a nitride layer on a substrate and an oxide layer thereon, and after forming an insulating layer and an element thereon, the oxide layer is formed in the layer by physical means. Or the method of peeling in the interface is disclosed. However, since it is necessary to form the above-mentioned layer to be peeled on the substrate, the manufacturing process is complicated, leading to an increase in manufacturing cost.

As described above, there is a need for a means that does not peel off the flexible substrate from the support in the formation of the functional layer, and then peels the flexible substrate from the support without damaging the flexible substrate and the functional layer, and that can be easily carried out at low cost is becoming

Japanese Patent Laid-Open No. 2010-202729 Japanese Patent Laid-Open No. 2012-140560 Japanese Patent Laid-Open No. 2003-174153

As described above, by forming a flexible substrate on a rigid support such as a glass substrate in advance to form a functional layer in a state in which the flexible substrate is fixed to the rigid support and separating it from the rigid support, the method of manufacturing a flexible device includes various functional layers It is considered to be advantageous from the viewpoint of being able to form with high precision and excellent handleability at the time of manufacture. However, when the flexible device is separated from the rigid support, it cannot be easily separated, the flexible substrate is damaged, and various troubles, such as affecting the functional layer, may occur. In addition, the method known so far is not sufficient from the viewpoint of lowering the manufacturing cost and being applicable to various resins, and further improvement is required.

Therefore, it is an object of the present invention to provide a method for manufacturing a flexible device that is simple, has a low manufacturing cost, has versatility that can be applied to various resins, and is easy to remove a rigid support from a flexible substrate on which a functional layer is formed. is to provide.

That is, the present invention provides a flexible substrate forming process of forming a flexible substrate on a rigid support by applying a resin solution on a rigid support, a functional layer forming process of forming a functional layer on the flexible substrate, and the functional layer formed on the flexible substrate A method of manufacturing a flexible device comprising each step of a support removal step of removing a substrate from a rigid support together with a functional layer, wherein in the flexible substrate forming step, a resin solution is applied after heat-treating the rigid support A method of manufacturing a flexible device.

Moreover, in this invention, it is preferable that the maximum temperature of the said heat processing is 300 degreeC or more, and it is more preferable that it is 360 degreeC or more.

Further, in the present invention, it is preferable to apply the resin solution on the rigid support within 180 minutes after the end of the heat treatment.

In addition, the present invention is a flexible device manufactured by the method of manufacturing the flexible device. Among them, the flexible device is preferably a touch panel.

In addition, the present invention is an apparatus for manufacturing a flexible device for a method for manufacturing a flexible device, characterized in that it comprises an apparatus for continuously heat-treating a rigid support at 300°C or higher, preferably 360°C or higher.

Moreover, this invention is a resin solution for forming the flexible board|substrate in the said flexible device.

(Effects of the Invention)

The manufacturing method of the flexible device of the present invention does not need to add a complicated process such as providing a release layer, and since the flexible device can be obtained by applying it to various resins, it is possible to suppress the increase in manufacturing cost due to the introduction of new equipment. and it is possible to utilize the existing manufacturing technology for glass substrates. Therefore, substitution from a glass substrate to a flexible substrate can be accelerated|stimulated with respect to electronic devices, such as a liquid crystal display, organic electroluminescent display, a solar cell, a touch panel, and a color filter.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic explanatory drawing which shows the flexible device manufacturing apparatus of this invention.

Hereinafter, one aspect of the manufacturing method of the flexible device of this invention is demonstrated in detail.

The method of manufacturing a flexible device of the present invention is a method of manufacturing a flexible device having a functional layer having a predetermined function on a flexible substrate, and includes the following three steps.

(1) a flexible substrate forming process of forming a flexible substrate on the rigid support by applying a resin solution on the rigid support;

(20 A functional layer forming process of forming a functional layer on the flexible substrate;

(3) Each process of the support body removal process which removes a rigid support body from the flexible substrate on which the said functional layer was formed.

And in this invention, after heat-processing a hard support body in the said flexible board|substrate formation process, the resin solution is apply|coated.

First, the flexible substrate forming process will be described.

The hard support is not limited in its kind as long as it is an inorganic material and can ensure performance as a laminate, and examples thereof include glass, ceramics, and metals. Here, the metal includes copper, aluminum, stainless steel, iron, silver, palladium, nickel, chromium, molybdenum, tungsten, zirconium, gold, cobalt, titanium, tantalum, zinc, lead, tin, silicon, bismuth, indium, or an alloy thereof. One or two or more metal materials selected from the group consisting of can be exemplified, and may be formed by compounding with glass, and these are preferable from the viewpoint of heat resistance and support of the flexible substrate layer. Examples of the ceramic include alumina, silica, and silicon wafers. More preferably, it is glass excellent in the suitability to the manufacturing process of the existing flexible device.

In addition, for these rigid supports, for the purpose of adjusting the surface properties and improving adhesion with the flexible substrate, sizing, chrome plating, nickel plating, chrome-nickel plating, copper-zinc alloy plating, copper oxide precipitation or Aluminum alcoholate, aluminum chelate, silane coupling agent, titanate-based coupling agent, titanium compounds such as alkoxy titanium, silane compounds such as alkoxysilane, triazinethiols, benzotriazoles, acetylene alcohols, acetylacetones, catechols , o-benzoquinones, tannins, chemical surface treatment such as quinolinols, or mechanical surface treatment such as surface roughening treatment may be performed.

A resin solution is applied on the rigid support to form a flexible substrate on the rigid support. The resin solution is obtained by dissolving a known resin in a known solvent. As for resin, polybenzoxazole, polyamideimide, a polyimide, or a polyimide precursor is mentioned, for example. Preferably, it is a polyimide or polyimide precursor excellent in heat resistance and chemical-resistance when it is set as a flexible substrate. Examples of the solvent include N-methylpyrrolidone (NMP), dimethylformamide (DMF), dimethylacetamide (DMAc), dimethylsulfoxide (DMSO), dimethyl sulfate, sulfolane, butyrolactone, cresol, phenol, halogenated phenol, cyclohexanone, dioxane, tetrahydrofuran, diglyme, triglyme, carbonate (dimethyl carbonate, diethyl carbonate, ethylmethyl carbonate, ethylene carbonate, propylene carbonate, etc.) and the like.

When the resin is a polyimide or polyamide precursor, a resin solution containing polyimide or a polyimide precursor is applied to a rigid support, and the rigid support is heat-treated to cure the resin solution to obtain a flexible substrate. At this time, the layer of the resin solution before hardening is called "pre-polyimide resin layer."

When the flexible substrate is formed of polyimide, the structure of the polyimide can function without particular limitation, but since it is easy to remove from the rigid support, it is a polyimide having an alicyclic structure in the main chain backbone (hereinafter referred to as “alicyclic-containing polyimide”). ) or a polyimide having a fluorine atom (hereinafter referred to as "fluorine-containing polyimide") is preferable. As an example of an alicyclic-containing polyimide, an alicyclic structure-containing diamino compound such as 9,9-bis(4-aminophenol)fluorene (DCHM) and cyclohexylamine (CHA) as a monomer, or 1,2,4,5- It has at least 1 type or more of alicyclic structure containing acid anhydrides, such as cyclohexane tetracarboxylic dianhydride (CHDA) and 1,2,4,5- cyclocyclobutane tetracarboxylic dianhydride (CBDA), It is a polyimide it was done with Examples of the fluorine-containing polyimide include, as a monomer, a fluorine-containing diamino compound such as 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB), or 2,2-bis(3). , 4-anhydrodikyrboxyphenyl) hexafluoropropane (6FDA), 9,9-bis (trifluoromethyl) xanthene tetracarboxylic dianhydride (6FCDA), 9-phenyl-9- (trifluoro It has at least 1 type or more of fluorine-containing acid anhydrides, such as romethyl) xanthene tetracarboxylic dianhydride (3FCDA), and made this into a polyimide precursor. More preferably, it is a fluorine-containing polyimide, More preferably, it is a fluorine-containing polyimide which has TFMB as a fluorine-containing diamino compound and 6FDA as a fluorine-containing acid anhydride.

Any coating method can be used for formation of the prepolyimide resin layer. Moreover, you may form the prepolyimide resin layer of multiple layers on a hard support body. In the case of forming a plurality of layers, the following three methods are preferable because the precision such as the film thickness is high.

Method 1) Two or more types of prepolyimide resin layers are simultaneously formed by a multilayer die.

Method 2) After forming the prepolyimide resin layer by any method, another prepolyimide resin layer is formed on the undried coated surface by a knife coating method or a die method or the like.

Method 3) After forming and drying a prepolyimide resin layer by an arbitrary method, another prepolyimide is formed in the resin layer by an arbitrary method on the coated surface.

The night coat method described here is a method of applying the resin solution evenly with a bar, squeegee, knife, or the like.

Arbitrary methods can be used as a hardening method of a prepolyimide resin layer. After forming the prepolyimide resin layer, the hard support including the pre-dried prepolyimide resin layer is left standing for a certain period of time at a high temperature in a batch-type heat-drying furnace, or the laminate in the furnace of a continuous heat treatment apparatus. By controlling the movement speed of the substrate to secure the time and temperature for drying and curing, a flexible substrate made of a single or multiple polyimide resin layers can be formed.

When the polyimide resin layer is cured, the solvent is removed from the prepolyimide resin layer by heat treatment and heating. In particular, when a polyimide precursor resin solution is used, an imide bond is further formed by a ring-opening reaction (hereinafter referred to as "imidization"). Curing conditions are appropriately adjusted depending on the chemical structure of polyimide and polyimide precursor, the structure of the heat treatment device, etc., which will be described later. However, if the heat treatment is rapidly heated to a high temperature, a skin layer is generated on the surface of the resin layer, making it difficult to evaporate the solvent, or foaming. Therefore, it is preferable to heat-process while raising it from low temperature to high temperature gradually.

When the prepolyimide resin layer is a polyimide precursor, the heat treatment conditions at the time of curing are preferably a lower heat treatment temperature in order to suppress thermal deterioration and manufacturing cost of the flexible substrate in the manufacturing process, and heat treatment time is preferably shorter. However, if the heat treatment temperature is too low or the heat treatment time is too short, there is a fear that the curing may not be sufficiently performed. good night. If it is this temperature range, imidation advances efficiently. In addition, it is possible to sufficiently remove adsorbates derived from atmospheric components, moisture, and the like distributed on the surface of the rigid support. More preferably, the maximum temperature is 320°C or more, and the holding time at the maximum temperature is 2 minutes or more. More preferably, the maximum temperature is 360°C or more, and the holding time at the maximum temperature is 2 minutes or more.

On the other hand, when a prepolyimide resin layer is a polyimide, it hardens by drying. Therefore, the heat processing temperature may be lower than the case of a polyimide precursor. As for the heat processing temperature in this case, it is preferable that the highest temperature is 280 degreeC or more, More preferably, it is 300 degreeC or more.

In addition, curing can be performed under any condition in air and in an inert gas such as nitrogen or argon. In addition, any conditions of under normal pressure, under reduced pressure, under pressure, and under vacuum can be performed.

Moreover, you may perform formation of a prepolyimide resin layer and formation of a flexible board|substrate continuously with a continuous heat processing apparatus.

In addition, in the flexible substrate forming step, the resin solution is applied after the hard support is heat-treated. The heat treatment of the hard support before application of this resin solution is also referred to as "pre-heat treatment". By performing the pre-heating treatment, the flexible substrate is not peeled from the rigid support in the functional layer forming step, and the rigid support is removed from the flexible substrate without damaging the rigid support, the flexible substrate and the functional layer in the paper material removal step. can Specifically, if the pre-heating treatment is not performed, the peel strength of the rigid support-flexible substrate is too high, and when the rigid support is removed, the rigid support, the flexible substrate or the functional layer may be damaged, such as cracks, cracks, etc. By performing the pre-heating treatment, the peeling strength of the rigid support-flexible substrate is suppressed to such an extent that peeling does not occur in the functional layer forming process, so that the support removal process can be performed without the above damage.

The conditions of the pre-heating treatment differ depending on the rigid support and resin solution used, but from the viewpoint of removing impurities on the rigid support and maintaining the peel strength of the rigid support-flexible substrate in an appropriate range, the maximum temperature of the heat treatment is 300 It is preferable that it is more than °C. More preferably, the maximum temperature of the preheating treatment is 360°C or higher. The atmosphere at the time of heating may be any atmosphere in the atmosphere, in an inert gas, or under a reduced pressure environment, but it is preferable to use the atmosphere in the atmosphere from the viewpoint of suppressing the manufacturing cost and high efficiency of increasing the surface of the rigid support. In addition, for example, when using glass as a hardening support body, the upper limit of the maximum temperature of this preheating process is substantially 500 degreeC from a viewpoint of suppressing a thermal deformation and a viewpoint of suppressing manufacturing cost.

In addition, in order to prevent adhesion of impurities and moisture to the hard support subjected to the heat treatment, it is preferable to apply the resin solution on the hard support within 180 minutes after the end of the heat treatment. More preferably, it is within 120 minutes. On the other hand, if the resin solution is applied while the remaining time has not passed after the heat treatment, there is a possibility that the flexible substrate may be expanded or deteriorated due to the heat of the rigid support. Therefore, it is preferable to apply the resin solution in a state where the temperature of the hard support is 40° C. or less after heat treatment. Here, the end of the heat treatment refers to the time when the cooling of the rigid support is started after the heat treatment. The cooling method is exemplified by cooling, forced cooling by blowing, and the like.

Next, the functional layer formation process is demonstrated. A functional layer is formed on the flexible substrate obtained in the flexible substrate forming process. As a functional layer, although the element which guarantees the function of a well-known flexible device is applicable, For example, organic electroluminescent TFT and a photoelectric conversion element. An electronic paper driving element, a color filter, etc. are exemplified. In the case of manufacturing an organic EL display as a flexible device, TFT for image driving is exemplified as the functional layer. A silicon semiconductor or an oxide semiconductor is illustrated as a material of TFT. When a conventional flexible substrate is not used, a barrier layer made of an inorganic component is formed on a rigid support such as plate glass, and a TFT is formed thereon. At the time of this formation, high-temperature treatment (300° C. to 400° C. range) is required. Therefore, it is important that the flexible substrate also be able to withstand this high-temperature treatment. Moreover, for example, when manufacturing a touch panel as a flexible device, electrode layers, such as a transparent conductive film and a metal mesh, are formed as a functional layer. Examples of the transparent conductive film include tin-doped indium oxide (ITO), SnO, ZnO, and IZO. When these electrode layers are formed, a conductive layer having a small resistance can be formed by performing heat treatment at 200°C or higher. Therefore, it is important that the flexible substrate also be able to withstand this high-temperature treatment.

Next, the support body removal process is demonstrated. The rigid support is removed from the flexible substrate on which the functional layer is formed. When removing, a cut line may be formed in the periphery of the surface of the portion in which the functional layer is formed on the flexible substrate (hereinafter, referred to as "functional layer formation part") by any method to partition the frame body. By forming the cut line, the size and shape of the flexible substrate on which the functional layer is formed can be controlled. For example, in order to increase manufacturing efficiency, when a plurality of functional layers are formed on one flexible substrate, the size and shape of the plurality of flexible substrates may be matched by forming cut lines. As the area of the frame body decreases, the area of the flexible substrate may increase, and a functional layer that may be formed on one flexible substrate may be increased. Therefore, it is preferable that the area of the frame body be smaller within the range in which the size and shape of the flexible substrate can be controlled.

Further, the flexible substrate in the inner region divided by the cut line is peeled from the rigid support together with the functional layer to obtain a flexible device having the functional layer on the flexible substrate. A well-known method can be used as the method of the said peeling unless the quality of the flexible device obtained is reduced. A well-known method can also be used for peeling of a frame body. Either of peeling of a flexible board|substrate and peeling of a frame body may be performed first. In the case where an incision is not formed, the entire flexible substrate is peeled off together with the functional layer.

As described above, the method for manufacturing the flexible device of the present invention can appropriately control the peel strength of the rigid support-flexible substrate by a simple method of heat treatment of the rigid support. As a result, when the flexible device is separated from the rigid support, the flexible device can be manufactured without damaging the rigid support, the flexible substrate, and the functional layer. Therefore, it is expected that the flexible device manufactured by this manufacturing method has a high manufacturing yield and a long product life.

Next, the flexible device manufacturing apparatus of this invention is demonstrated. The flexible device manufacturing apparatus is characterized in that the flexible substrate forming process is continuously performed. The apparatus which heat-processes a hard support body as specifically, shown in FIG. 1 at 300 degreeC or more continuously is provided. As an example, the flexible device manufacturing apparatus 10 shown in FIG. 1 is demonstrated below. When the rigid support 11 is placed on the conveyor 16 , the rigid support 11 moves in the direction of the arrow on the conveyor 16 . The rigid support 11 is heated at a maximum temperature of 300° C. or higher in the first continuous heat treatment device 13 (pre-heating treatment). After heating, the resin solution supplied from the resin solution supply device 14 is applied to the surface of the rigid support 11 . Thereafter, the highest temperature in the second continuous heat treatment apparatus 15 is heated to 300° C. or higher (post-heat treatment), and the flexible substrate 12 is formed on the rigid support 11 .

As another example, the flexible device manufacturing apparatus which consists of the following processes 1-7 is illustrated.

(Step 1) The hard support is taken out from the stocker (storage device), put in an oven, and heated at a maximum temperature of 300°C or higher (pre-heating treatment).

(Step 2) After heating, the hard support is taken out from the oven, and a resin solution is applied to the surface of the hard support with a coater.

(Step 3) The hard support coated with the resin solution is dried in a vacuum dryer, hot plate or oven, and a prepolyimide resin layer is formed on the hard support.

(Step 4) The rigid support on which the prepolyimide resin layer is formed is put into a continuous heat treatment apparatus and heated at a maximum temperature of 300° C. or higher to form a flexible substrate (post-heat treatment). The inside of the continuous heat treatment apparatus is conveyed by a metal conveyor or roll.

(Step 5) The rigid support on which the flexible substrate is formed is copied to a functional layer forming apparatus to form a functional layer in a continuous batch manner.

(Step 6) The flexible substrate on which the functional layer is formed and the rigid support are separated by a peeler.

(Step 7) The peeled hard support is washed and moved to a stocker.

In the above steps 1 to 7, a robot may be used to move the rigid support or the like, or it may be performed manually.

[Example]

Hereinafter, the present invention will be specifically described based on Examples and Comparative Examples. In addition, the present invention is not limited to these contents.

1. Various physical properties measurement and performance test methods

[Measurement of peel strength]

The peel strength between the hard support and the polyimide resin layer is obtained by cutting the polyimide side or pattern etching at the substrate side with a line width (about 1 mm to 30 mm) suitable for measurement of the laminate, and manufactured by Toyo Seiki Co., Ltd. The resin layer was peeled off in the 180 degree direction using the tensile tester (strograph M1), and the peeling strength was measured. In addition, the thing in which peeling was difficult because the adhesion|attachment between a processed fine wire and a resin interface was strong was set as "peelability impossible".

2. Synthesis of polyamic acid (polyimide precursor) solution

Raw materials used for the synthesis of polyamic acid (polyimide precursor) solutions handled in the following synthesis examples, examples and comparative examples, aromatic diamino compounds, acid anhydride compounds of aromatic tetracarboxylic acids, acid anhydrides containing alicyclic structures, solvents is shown below.

[aromatic diamino compound]

4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB)

4,4'-diaminodiphenyl ether (44DAPE)

[Acid anhydride compound of aromatic tetracarboxylic acid]

· Pyromellitic anhydride (PMDA)

· 2,2-bis (3,4-anhydrodicarboxyphenyl) hexafluoropropane (6FDA)

2,3,2',3'-biphenyltetracarboxylic dianhydride (BPDA)

[Acid anhydride containing alicyclic structure]

1,2,4,5-cyclohexanetetracarboxylic dianhydride (CHDA)

[solvent]

·N,N-dimethylacetamide (DMAc)

Synthesis Example 1

Under a stream of nitrogen, TFMB (15.8227 g) was added to 170 g of solvent DMAc with stirring in a 300 ml separable flask, warmed and dissolved at 20°C. 6FDA (7.5660 g) and PMDA (6.6113 g) were then added. Thereafter, the solution was stirred at room temperature for 4 hours to carry out polymerization reaction to obtain 200 g of a pale yellow viscous polyamic acid A varnish. Furthermore, polyimide resin A is obtained by hardening|curing this polyamic-acid A varnish on the heating conditions mentioned later.

Synthesis Example 2

In the same manner as in Synthesis Example 1 except that TFMB (16.93 g) as an aromatic diamino compound and PMDA (10.12 g) and 6FDA (2.95 g) as an acid anhydride compound of aromatic tetracarboxylic acid were used, 200 g of light yellow viscous A polyamic acid B varnish was obtained. Furthermore, polyimide resin B is obtained by hardening|curing this polyamic-acid B varnish on the heating conditions mentioned later.

Synthesis Example 3

200 g of pale yellow viscous polyamic acid C varnish was prepared in the same manner as in Synthesis Example 1 except that TFMB (12.54 g) was used as the aromatic diamino compound and 6FDA (17.46 g) was used as the acid anhydride compound of aromatic tetracarboxylic acid. got it Furthermore, polyimide resin C is obtained by hardening|curing this polyamic-acid C varnish on the heating conditions mentioned later.

Synthesis Example 4

200 g of pale yellow viscous polyamic acid D varnish was prepared in the same manner as in Synthesis Example 1 except that TFMB (12.31 g) was used as the aromatic diamino compound and 6FCDA (17.69 g) was used as the acid anhydride compound of aromatic tetracarboxylic acid. got it Furthermore, polyimide resin D is obtained by hardening|curing this polyamic-acid D varnish on the heating conditions mentioned later.

Synthesis Example 5

200 g of discolored viscous polyamic acid E varnish was prepared in the same manner as in Synthesis Example 1 except that 44DAPE (14.29 g) was used as the aromatic diamino compound and BPDA (15.65 g) was used as the acid anhydride compound of aromatic tetracarboxylic acid. got it Furthermore, polyimide resin E is obtained by hardening|curing this polyamic-acid E varnish on the heating conditions mentioned later.

Synthesis Example 6

200 g of a pale yellow viscous polyamic acid F varnish was obtained in the same manner as in Synthesis Example 1 except that TFMB (17.60 g) as the aromatic diamino compound and CHDA (12.37 g) as the alicyclic structure-containing acid anhydride were used. Furthermore, polyimide resin F is obtained by hardening|curing this polyamic-acid F varnish on the heating conditions mentioned later.

3. Formation of polyimide layer on support substrate and performance evaluation

The rigid supports handled in the following Examples and Comparative Examples are shown below.

・Glass plate… Corning's alkali-free glass, trade name "Eagle XG", thickness 500㎛

The polyamic acid varnish applied on the hard support was dried on a hot plate at 70°C to 100°C, and then cured by raising the temperature from 100°C to 360°C for about 30 minutes.

Example 1

A clean glass sheet (15 cm×15 cm) was heated in an oven at 360° C. in the air for 60 minutes, cooled in the air, and after wiping the surface with acetone, polyamic acid A varnish was applied on the surface. The time from completion of heating to application was 60 minutes. This was heated under the above heating conditions to form a flexible substrate having a thickness of 25 µm. Next, a cut line was formed on this flexible board|substrate with a cutter, and the frame body of 10 mm x 10 mm was partitioned in the polyimide resin layer. And the flexible board|substrate of the inner area|region surrounded by the incision line was peeled. The peel strength is shown in Table 1.

Examples 2-7

As shown in Table 1 below, Example 2 was carried out in the same manner as in Example 1 except that the polyamic acid B varnish was used instead of the polyamic acid A varnish, and the polyamic acid A varnish was replaced with the polyamic acid A varnish of Example 1 When varnish C was used (Example 3), when polyamic acid D varnish was used as follows (Example 4), when polyamic acid E varnish was used (Example 5), when polyamic acid F varnish was used With respect to (Example 6), a flexible substrate having a thickness of 25 µm was formed in the same manner as in Example 1 except for that, and the flexible substrate was further peeled off. The peel strength is shown in Table 1.

Example 5

A flexible substrate having a thickness of 25 µm was formed in the same manner as in Example 1 except that the oven was heated at 300°C in the air for 60 minutes, and the flexible substrate was further peeled off. The peel strength is shown in Table 1.

Example 6

200 minutes after the end of the heat treatment, a flexible substrate having a thickness of 25 µm was formed in the same manner as in Example 1 except that the polyimide acid A varnish on the surface was applied, and the flexible substrate was also peeled off. The peel strength is shown in Table 1.

Comparative Example 1

Except not heating the glass sheet, it carried out similarly to Example 1, the flexible board|substrate was formed and it peeled. The results are shown in Table 1.

Example
One Example
2 Example 3 Example
4 Example
5 Example
6 Example
7 Example
8 comparative example
One polyimide resin A B C D E F A A A flexible substrate
Thickness (㎛) 25 25 25 25 25 25 25 25 25 peel strength
(N/m) 4.7 4.6 4.4 3.9 2 5 5.3 4.7 16.4

As can be seen from the results of these Examples and Comparative Examples, good peel strength can be obtained by heat-treating the hard support and then applying a resin solution to form a flexible substrate. Therefore, when the flexible substrate is formed on the rigid support in this way, a predetermined functional layer can be formed with high precision in the subsequent functional layer forming step, and in the support removing step, the flexible substrate is removed from the rigid support together with the functional layer. Since it can be easily removed, the flexible device can be easily manufactured at low cost.

10: flexible substrate manufacturing apparatus 11: rigid support
12: flexible substrate 13: first continuous heat processing device
14: resin solution supply device 15: second continuous heat treatment device
16: conveyor

Claims (7)

A flexible substrate forming process of forming a flexible substrate on a rigid support by applying a resin solution on a rigid support, a functional layer forming process of forming a functional layer on the flexible substrate, and a functional layer of the flexible substrate on which the functional layer is formed; A method of manufacturing a flexible device comprising each step of a support removal step of removing from a rigid support together,
In the flexible substrate forming process, a method of manufacturing a flexible device, characterized in that the resin solution is applied after the hard support is heat-treated without providing a release layer. The method of claim 1,
A method of manufacturing a flexible device, wherein the maximum temperature of the heat treatment is 300° C. or higher. 3. The method of claim 1 or 2,
A method of manufacturing a flexible device, characterized in that the resin solution is applied on the rigid support within 180 minutes after the end of the heat treatment. delete delete A resin solution supply device for continuously supplying a resin solution to the surface of a hard support, and a heat treatment device for continuously heating the resin solution applied to the surface of the hard support, the flexible according to claim 1 or 2 An apparatus for performing a flexible substrate forming process in a device manufacturing method,
and a heat treatment device for continuously heat-treating the rigid support at 300°C or higher before the resin solution supply device. delete

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