KR20200000813A - Method for producing transparent resin film - Google Patents

Abstract

The purpose of the present invention is to provide a method of manufacturing a transparent resin film having good quality even when performing a heat treatment process and comprising at least one resin selected from the group consisting of a polyimide-based resin and a polyamide-based resin. The method according to the present invention is a film manufacturing method comprising heat-treating the transparent resin film while transferring the transparent resin film within a tenter type dryer having a clip chain group which is formed in both end portions of the transparent resin film and composed of a plurality of clip chains, when using, as a clip chain, a member including: a resin film gripping part gripping an end portion of a long band-like transparent resin film formed by comprising at least one resin selected from the group consisting of the polyimide-based resin and the polyamide-based resin and 0.1 to 30 mass% of an organic solvent with respect to mass of the transparent resin film; a driving metal chain part driven by a metallic sprocket; and a metallic bearing part changing position of the resin film gripping part along metallic rails, wherein contact portions of the metal parts are lubricated by using a lubricant having a kinematic viscosity at 40°C of 100 to 800 mm^2/s.

Description

Manufacturing method of transparent resin film {METHOD FOR PRODUCING TRANSPARENT RESIN FILM}

This invention relates to the manufacturing method of a transparent resin film.

In a flexible display device, a transparent resin film is required to replace glass. As a material of such a transparent resin film, materials having transparency and mechanical strength, such as polyimide resins and polyamide resins, are known.

In manufacture of such a transparent resin film, in order to acquire desired quality, heat processing of a resin film may be performed, for example, it may be heat-processed using a tenter type drying apparatus.

By the way, in such heat processing, lubricating oil may be used in order to reduce the friction between the metal components used for a dryer (for example, patent document 1 etc.).

The invention described in Patent Literature 1 discloses the use of a polyalkyl ether compound as a lubricant having excellent thermal stability without high hydrolysis and high affinity with a resin film. However, in the examples, the use temperature is not specifically disclosed.

Japanese Laid-Open Patent Publication No. 2014-137123

This invention is proposed in view of such a situation, and manufacture of the transparent resin film containing at least 1 sort (s) of resin chosen from the group which consists of polyimide-type resin and polyamide-type resin which have favorable quality even if it heat-processes. It is an object to provide a method.

That is, the present invention provides the following.

[1] A long band-shaped transparent resin film comprising at least one resin selected from the group consisting of polyimide resins and polyamide resins, and an organic solvent of 0.1 to 30% by mass relative to the mass of the transparent resin film. of,

When the member which has the resin film holding part holding the edge part of the said transparent resin film, the drive metal chain part driven by the metal sprocket, and the metal bearing part which changes the position of the resin film holding part along a metal rail is used as a clip chain. As a manufacturing method of the film which heat-processes, conveying the said transparent resin film in the tenter type dryer which has the clip chain group which consists of several clip chains corresponding to both ends of a transparent resin film,

The manufacturing method of the transparent resin film which makes the contact part of this metal component lubricate using lubricating oil whose kinematic viscosity in 40 degreeC is 100 mm <^2> / s or more and 800 mm <^2> / s or less.

[2] The production method according to [1], wherein the kinematic viscosity is 100 mm ² / s or more and less than 800 mm ² / s.

[3] The production method according to [1] or [2], wherein the kinematic viscosity is 400 mm ² / s or more and 500 mm ² / s or less.

[4] The production method according to any one of [1] to [3], wherein the temperature of the heat treatment is 50 to 350 ° C.

[5] The production method according to any one of [1] to [4], wherein the transport speed of the transparent resin film is 0.1 to 15 m / min.

[6] irradiating light at an angle of 20 to 70 ° with respect to the resin film surface, visually identifying the contamination point from an angle of 90 ° from the resin film surface, performing IR measurement of the contamination point, and detecting the used lubricant oil. Resin film whose number is 0 piece / m <^2> or 1-5 piece / m <^2> .

[7] A flexible display device comprising the resin film according to [6].

[8] The flexible display device according to [7], further comprising a touch sensor.

[9] The flexible display device according to [7] or [8], further comprising a polarizing plate.

As mentioned above, this invention provides the manufacturing method of the transparent resin film which can obtain a homogeneous transparent resin film.

1 shows an example of a heat treatment furnace for producing a transparent resin film according to the present invention. The film is conveyed from the left side of the paper to the right side. (a) shows the side view of a furnace, and the center line shows the situation where a film is conveyed. (b) shows the top view of a furnace, and the center square shows the film conveyed.

The material, dimensions, etc. which are illustrated in the following description are examples, and this invention is not necessarily limited to them, It is possible to change suitably in the range which does not change the summary.

This invention is an elongate strip-shaped transparent resin which consists of 0.1-30 mass% organic solvent with respect to the mass of a transparent resin film, and at least 1 sort (s) of resin chosen from the group which consists of polyimide resin and polyamide resin. Film,

When the member which has the resin film holding part holding the edge part of the said transparent resin film, the drive metal chain part driven by the metal sprocket, and the metal bearing part which changes the position of the resin film holding part along a metal rail is used as a clip chain. As a manufacturing method of the film which heat-processes, conveying the said transparent resin film in the tenter type dryer which has the clip chain group which consists of several clip chains corresponding to both ends of a transparent resin film,

The manufacturing method of the transparent resin film which lubricates the contact part of this metal part using lubricating oil whose kinematic viscosity in 40 degreeC is 100 mm <^2> / s or more and 800 mm <^2> / s or less is provided.

[Polyimide Resin, Polyamide Resin]

The transparent resin film of this invention contains at least 1 sort (s) of resin chosen from the group which consists of polyimide resin and polyamide resin. A polyimide-based resin is a polymer containing a repeating structural unit containing an imide group (hereinafter may be described as polyimide), and a polymer containing a repeating structural unit containing both an imide group and an amide group (hereinafter, At least 1 sort (s) of polymer chosen from the group which consists of polyamide-imide) may be shown. Moreover, polyamide resin represents the polymer containing the repeating structural unit containing an amide group.

It is preferable that polyimide-type resin has a repeating structural unit represented by Formula (10). Here, G is a tetravalent organic group and A is a divalent organic group. The polyimide resin may include a repeating structural unit represented by two or more types of formulas (10) in which G and / or A are different.

The polyimide resin may include one or more selected from the group consisting of repeating structural units represented by formulas (11), (12) and (13) within a range that does not impair various physical properties of the transparent resin film. .

Formula (10) and (11) of the, G and G ¹ are, each independently, a tetravalent organic group, preferably an organic group which may be substituted with a hydrocarbon group or fluorine-substituted hydrocarbons. Examples G and G ^1, formula 20, formula 21, formula 22, formula 23, formula 24, formula 25, formula 26, formula 27, formula 28 Or the group represented by Formula (29) and a tetravalent hydrocarbon group of 6 or less carbon atoms are illustrated. Since it is easy to suppress the yellowness (YI value) of a transparent resin film, Especially, Formula (20), Formula (21), Formula (22), Formula (23), Formula (24), Formula (25), The group represented by Formula (26) or Formula (27) is preferable.

In formulas (20) to (29),

* Represents a bonding hand,

Z is a single bond, -O-, -CH _2- , -CH ₂ -CH _2- , -CH (CH ₃ )-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -,- Ar-, -SO _2- , -CO-, -O-Ar-O-, -Ar-O-Ar-, -Ar-CH ₂ -Ar-, -Ar-C (CH ₃ ) ₂ -Ar- or -Ar-SO ₂ -Ar- is represented. Ar represents the C6-C20 arylene group which may be substituted by the fluorine atom, and a phenylene group is mentioned as a specific example.

Equation (12), G ² is a trivalent organic group, preferably an organic group which may be substituted with a hydrocarbon group or fluorine-substituted hydrocarbons. Examples of G ^2, formula 20, formula 21, formula 22, formula 23, formula 24, formula 25, formula 26, formula 27, formula 28 or formula Examples in which any one of the bonds of the group represented by (29) are substituted with a hydrogen atom and a trivalent C 6 or less chain hydrocarbon group are exemplified.

Expression (13) in, G ³ is a divalent organic group, preferably an organic group which may be substituted with a hydrocarbon group or fluorine-substituted hydrocarbons. Examples of G ^3, formula 20, formula 21, formula 22, formula 23, formula 24, formula 25, formula 26, formula 27, formula 28 or formula Among the bonds of the group represented by (29), groups in which two non-adjacent groups are substituted with hydrogen atoms and a chain hydrocarbon group having 6 or less carbon atoms are exemplified.

In Formulas (10) to (13), A, A ¹ , A ^2, and A ³ are each independently a divalent organic group, and may preferably be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group. It is an organic group. As the A, A ^1, A ² and A ^3, formula 30, formula 31, formula 32, formula 33, formula 34, formula 35, formula 36, formula (37 ) Or a group represented by formula (38); Groups in which they are substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; And a C6 or less chain hydrocarbon group is illustrated.

In formula (30)-formula (38),

* Represents a bonding hand,

Z ¹ , Z ² and Z ³ are each independently a single bond, -O-, -CH _2- , -CH ₂ -CH _2- , -CH (CH ₃ )-, -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -SO ₂ -or -CO-.

One example is that Z ¹ and Z ³ are -O-, and Z ² is -CH _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -or -SO _2- . The bonding position for each ring of Z ¹ and Z ² and the bonding position for each ring of Z ² and Z ³ are each preferably a meta position or a para position for each ring.

It is preferable that polyimide-type resin is a polyamideimide which has at least the repeating structural unit represented by Formula (10) and the repeating structural unit represented by Formula (13) from a viewpoint of being easy to improve visibility. Moreover, it is preferable that polyamide resin has at least the repeating structural unit represented by Formula (13).

In one embodiment of the present invention, the polyimide resin includes a diamine and a tetracarboxylic acid compound (tetracarboxylic acid compound flexible body such as an acid chloride compound and tetracarboxylic dianhydride); As needed, a dicarboxylic acid compound (dicarboxylic acid compound flexible bodies, such as an acid chloride compound), a tricarboxylic acid compound (tricarboxylic acid compound flexible bodies, such as an acid chloride compound and a tricarboxylic anhydride), etc. It is a condensation type polymer obtained by making it react (polycondensation). The repeating structural unit represented by formula (10) or formula (11) is usually derived from a diamine and a tetracarboxylic acid compound. The repeating structural unit represented by formula (12) is usually derived from diamine and tricarboxylic acid compounds. The repeating structural unit represented by Formula (13) is usually derived from diamine and dicarboxylic acid compound.

In one embodiment of the present invention, the polyamide-based resin is a condensed polymer obtained by reacting (polycondensation) a diamine and a dicarboxylic acid compound. That is, the repeating structural unit represented by Formula (13) is usually derived from diamine and dicarboxylic acid compound.

As a tetracarboxylic-acid compound, Aromatic tetracarboxylic-acid compounds, such as aromatic tetracarboxylic dianhydride; And aliphatic tetracarboxylic acid compounds such as aliphatic tetracarboxylic dianhydrides. A tetracarboxylic-acid compound may be used independently and may use 2 or more types together. In addition to the dianhydride, tetracarboxylic-acid compound flexible bodies, such as an acid chloride compound, may be sufficient as a tetracarboxylic-acid compound.

As a specific example of aromatic tetracarboxylic dianhydride, 4,4'- oxydiphthalic dianhydride, 3,3 ', 4,4'- benzophenone tetracarboxylic dianhydride, 2,2', 3,3'- Benzophenonetetracarboxylic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 2,2', 3,3'-biphenyltetracarboxylic dianhydride, 3,3 ', 4,4'-diphenylsulfontetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane Dianhydrides, 2,2-bis (3,4-dicarboxyphenoxyphenyl) propane dianhydrides, 4,4 '-(hexafluoroisopropylidene) diphthalic dianhydride (6FDA), 1,2-bis ( 2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,2-bis (3,4-dicarboxyphenyl) ethane dianhydride, 1, 1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, bis (2,3-dicarboxyphenyl Methane dianhydride, 4,4 '-(p-phenylenedioxy) diphthalic dianhydride, and 4,4'-(m-phenylenedioxy) diphthalic dianhydride. These can be used individually or in combination of 2 or more types.

As aliphatic tetracarboxylic dianhydride, cyclic or acyclic aliphatic tetracarboxylic dianhydride is mentioned. A cyclic aliphatic tetracarboxylic dianhydride is tetracarboxylic dianhydride which has alicyclic hydrocarbon structure, As a specific example, 1,2,4,5-cyclohexane tetracarboxylic dianhydride, 1,2, Cycloalkane tetracarboxylic dianhydrides, such as 3, 4- cyclobutane tetracarboxylic dianhydride, 1,2,3, 4- cyclopentane tetracarboxylic dianhydride, bicyclo [2.2.2] oct-7 -En-2,3,5,6-tetracarboxylic dianhydride, dicyclohexyl-3,3 ', 4,4'-tetracarboxylic dianhydride and these positional isomers are mentioned. These can be used individually or in combination of 2 or more types. Specific examples of the acyclic aliphatic tetracarboxylic dianhydride include 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-pentanetetracarboxylic dianhydride, and the like. Silver can be used individually or in combination of 2 or more types. Moreover, you may use combining a cyclic aliphatic tetracarboxylic dianhydride and an acyclic aliphatic tetracarboxylic dianhydride.

Among the tetracarboxylic dianhydrides, 1,2,4,5-cyclohexanetetracarboxylic dianhydride and bicyclo [2.2.2] oct-7-ene-2,3 from the viewpoint of high transparency and low colorability Preference is given to 5,6-tetracarboxylic dianhydride and 4,4 '-(hexafluoroisopropylidene) diphthalic dianhydride, and mixtures thereof. Moreover, you may use the aqueous addition of the anhydride of the said tetracarboxylic-acid compound as tetracarboxylic acid.

As a tricarboxylic acid compound, aromatic tricarboxylic acid, aliphatic tricarboxylic acid, those flexible acid chloride compounds, an acid anhydride, etc. are mentioned, You may use 2 or more types together.

Specific examples include anhydrides of 1,2,4-benzenetricarboxylic acid; 2,3,6-naphthalenetricarboxylic acid-2,3- anhydride; Phthalic anhydride and benzoic acid single _{bond, -CH 2 -, -C (CH} 3) 2 -, -C (CF 3) 2 -, -SO 2 - or can be connected to the compound group-phenylene.

As a dicarboxylic acid compound, aromatic dicarboxylic acid, aliphatic dicarboxylic acid, those flexible acid chloride compounds, an acid anhydride, etc. are mentioned, You may use together 2 or more types.

Specific examples thereof include terephthalic acid dichloride (terephthaloyl chloride (TPC)); Isophthalic acid dichloride; Naphthalenedicarboxylic acid dichloride; 4,4'-biphenyldicarboxylic acid dichloride; 3,3'-biphenyldicarboxylic acid dichloride; 4,4'-oxybis (benzoylchloride) (OBBC); Dicarboxylic acid compound of a chain hydrocarbon having 8 or less carbon atoms and two benzoic acids are a single bond, -CH _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -SO ₂ -or phenylene The compound connected by the group is mentioned.

As a diamine, an aliphatic diamine, aromatic diamine, or a mixture thereof is mentioned, for example. In addition, in this embodiment, "aromatic diamine" represents the diamine which the amino group couple | bonded with the aromatic ring directly, and may contain the aliphatic group or other substituent in a part of the structure. The aromatic ring may be monocyclic or condensed, and examples thereof include, but are not limited to, benzene ring, naphthalene ring, anthracene ring, fluorene ring and the like. Among these, it is preferable that an aromatic ring is a benzene ring. Moreover, "aliphatic diamine" shows the diamine which the amino group couple | bonded with the aliphatic group directly, and may contain the aromatic ring and other substituent in a part of the structure.

Examples of the aliphatic diamines include acyclic aliphatic diamines such as hexamethylenediamine and 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, norbornanediamine, and 4,4'-. Cyclic aliphatic diamine, such as diamino dicyclohexyl methane, etc. are mentioned. These can be used individually or in combination of 2 or more types.

As aromatic diamine, for example, p-phenylenediamine, m-phenylenediamine, 2,4-toluenediamine, m-xylylenediamine, p-xylylenediamine, 1,5-diaminonaphthalene, 2,6- Aromatic diamine which has one aromatic ring, such as diamino naphthalene; 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylether, 3,4'-diaminodiphenylether, 3,3'-dia Minodiphenylether, 4,4'-diaminodiphenylsulfone, 3,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 1,4-bis (4-aminophenoxy) Benzene, 1,3-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2- Bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2'-dimethylbenzidine, 2,2'-bis (tri Fluoromethyl) benzidine (2,2'-bis (trifluoromethyl) -4,4'-diaminodiphenyl (TFMB)), 4,4'-bis (4-aminophenoxy) biphenyl, 4 , 4'-diaminodiphenylether, 3,4'-diaminodiphenylether, 4,4'-diaminodiphenylmethane, 9,9-bis (4-aminophenyl) fluorene, 9,9- Bis (4-amino-3-methylphenyl) fluorene, 9,9-bis (4-amino-3-chlorofe ) Fluorene, 9,9-bis (4-amino there may be mentioned aromatic diamine having 3-fluorophenyl) fluorene, etc., an aromatic ring at least two. These can be used individually or in combination of 2 or more types.

Also in the said diamine, it is preferable to use 1 or more types chosen from the group which consists of aromatic diamine which has a biphenyl structure from a viewpoint of high transparency and low colorability, and it is 2,2'- dimethylbenzidine, 2,2'-bis ( It is more preferable to use one or more selected from the group consisting of trifluoromethyl) benzidine, 4,4'-bis (4-aminophenoxy) biphenyl and 4,4'-diaminodiphenyl ether, and 2 More preferably, 2'-bis (trifluoromethyl) benzidine is used.

The intermediate obtained after polyimide-type resin mixed each raw material, such as the said diamine, a tetracarboxylic acid compound, a tricarboxylic acid compound, a dicarboxylic acid compound, by a conventional method, for example, stirring, etc. Is obtained by imidization in the presence of an imidization catalyst and, if necessary, a dehydrating agent. Polyamide resin is obtained by mixing each raw material, such as the said diamine and a dicarboxylic acid compound, by a conventional method, for example, stirring.

Although it does not specifically limit as an imidation catalyst used in an imidation process, For example, Aliphatic amines, such as tripropylamine, dibutylpropylamine, ethyldibutylamine; Alicyclic amines (monocyclic) such as N-ethylpiperidine, N-propylpiperidine, N-butylpyrrolidine, N-butylpiperidine, and N-propylhexahydroazepine; Alicyclic amines (polycyclic) such as azabicyclo [2.2.1] heptane, azabicyclo [3.2.1] octane, azabicyclo [2.2.2] octane, and azabicyclo [3.2.2] nonane; And 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 3-ethylpyridine, 4-ethylpyridine, 2,4-dimethylpyridine, 2,4,6-trimethylpyridine, 3,4 Aromatic amines such as -cyclopentenopyridine, 5,6,7,8-tetrahydroisoquinoline, and isoquinoline.

Although it does not specifically limit as a dehydrating agent used at an imidation process, For example, acetic anhydride, a propionic anhydride, an isobutyric anhydride, a pivalic anhydride, butyric anhydride, an isovaleric anhydride, etc. are mentioned.

Although the reaction temperature is not specifically limited in the mixing and imidation process of each raw material, For example, it is 15-350 degreeC, Preferably it is 20-100 degreeC. Although reaction time is not specifically limited, for example, It is about 10 minutes-about 10 hours. If necessary, the reaction may be performed under inert atmosphere or reduced pressure. Moreover, reaction may be performed in a solvent, As said solvent, what is illustrated as a solvent used for preparation of a varnish, for example is mentioned. After the reaction, the polyimide resin or polyamide resin is purified. As a refining method, for example, a poor solvent is added to the reaction solution to precipitate a resin by reprecipitation, drying, taking out a precipitate, washing the precipitate with a solvent such as methanol and drying if necessary. Can be mentioned.

In addition, you may refer to the manufacturing method of Unexamined-Japanese-Patent No. 2006-199945 or Unexamined-Japanese-Patent No. 2008-163107 for manufacture of polyimide-type resin, for example. Moreover, a commercial item can also be used for polyimide-type resin, As a specific example, Neoprem (trademark) by Mitsubishi Gas Chemical Company, Inc., Kawamura Sangyo Co., Ltd. (Kawamura Sangyo Co., Ltd.) KPI-MX300F, etc., etc. are mentioned.

The weight average molecular weight of the polyimide resin or the polyamide resin is preferably 200,000 or more, more preferably 250,000 or more, more preferably 300,000 or more, even more preferably 350,000 or more, preferably 600,000 or less, More preferably, it is 500,000 or less, More preferably, it is 450,000 or less. The larger the weight average molecular weight of polyimide-based resin or polyamide-based resin is, the more likely it is to express high flex resistance when formed into a film. For this reason, it is preferable that a weight average molecular weight is more than the said minimum from a viewpoint of improving the bending resistance of a transparent resin film. On the other hand, the smaller the weight average molecular weight of the polyimide-based resin or the polyamide-based resin is, the easier the viscosity of the varnish is to be, and the tendency is to tend to improve the processability. Moreover, there exists a tendency for the stretchability of polyimide resin or polyamide resin to improve easily. For this reason, from a viewpoint of workability and stretchability, it is preferable that a weight average molecular weight is below the said upper limit. In addition, in this application, a weight average molecular weight can measure gel permeation chromatography (GPC), and it can calculate | require by standard polystyrene conversion, For example, it can calculate by the method as described in an Example.

The imidation ratio of polyimide-type resin becomes like this. Preferably it is 95 to 100%, More preferably, it is 97 to 100%, More preferably, it is 98 to 100%, Especially preferably, it is 100%. It is preferable that the imidation ratio is more than the said minimum from a viewpoint of the stability of a varnish and the mechanical physical property of the obtained transparent resin film. In addition, the imidation ratio can be calculated | required by IR method, NMR method, etc. It is preferable that the imidation ratio of the polyimide resin contained in a varnish from the said viewpoint exists in the said range. The imidation ratio can be obtained by, for example, the method described in Japanese Patent Application No. 2018-007523.

In a preferred embodiment of the present invention, the polyimide-based resin or the polyamide-based resin included in the transparent resin film of the present invention is halogen such as a fluorine atom which can be introduced by the fluorine-containing substituent or the like described above. It may contain an atom. When polyimide-type resin or polyamide-based resin contains a halogen atom, it is easy to improve the elasticity modulus of a transparent resin film and to reduce yellowness (YI value). When the elasticity modulus of a transparent resin film is high, it is easy to suppress generation | occurrence | production of a scratch, a wrinkle, etc. in the said film, and when yellowness of a transparent resin film is low, it becomes easy to improve transparency of the said film. The halogen atom is preferably a fluorine atom. As a preferable fluorine-containing substituent in order to contain a fluorine atom in polyimide resin or polyamide resin, a fluoro group and a trifluoromethyl group are mentioned, for example.

The content of the halogen atom in the polyimide resin or the polyamide resin is preferably 1 to 40% by mass, more preferably 5 to 40% by mass, based on the mass of the polyimide resin or the polyamide resin. More preferably, it is 5-30 mass%. When content of a halogen atom is 1 mass% or more, the elasticity modulus at the time of film-forming further improves, a water absorption is reduced, yellowness (YI value) is further reduced, and transparency is easy to improve more. There exists a tendency for synthesis | combination to become easy that content of a halogen atom is 40 mass% or less.

In one embodiment of the present invention, the content of the polyimide resin and / or the polyamide resin in the transparent resin film is preferably 40% by mass or more, more preferably based on the total mass of the transparent resin film. Is 50 mass% or more, More preferably, it is 70 mass% or more. It is preferable that content of polyimide-type resin and / or polyamide-type resin is more than the said minimum from a viewpoint of easy bending resistance etc. to improve. In addition, content of polyimide-type resin and / or polyamide-type resin in a transparent resin film is 100 mass% or less normally with respect to the total mass of a transparent resin film.

[additive]

The transparent resin film of this invention may further contain additives, such as a filler. As such an additive, a silica particle, an ultraviolet absorber, a brightener, a silica dispersing agent, antioxidant, a pH adjuster, and a leveling agent are mentioned, for example.

(Silica particles)

The transparent resin film of this invention may further contain a silica particle as an additive. Content of a silica particle becomes like this. Preferably it is 1 mass% or more, More preferably, it is 3 mass% or more, More preferably, it is 5 mass% or more with respect to the gross mass of the said transparent resin film. Moreover, content of a silica particle becomes like this. Preferably it is 60 mass% or less, More preferably, it is 50 mass% or less, More preferably, it is 45 mass% or less with respect to the gross mass of the said transparent resin film. Moreover, content of a silica particle can select and combine arbitrary lower limits and an upper limit among these upper limits and the lower limits. When content of a silica particle is the numerical range of the said upper limit and / or a lower limit, in the transparent resin film of this invention, since a silica particle is hard to aggregate and there exists a tendency to disperse | distribute uniformly to a primary particle state, in the present invention The fall of the visibility of a transparent resin film can be suppressed.

The particle diameter of the silica particles is preferably 1 nm or more, more preferably 3 nm or more, more preferably 5 nm or more, particularly preferably 8 nm or more, preferably 30 nm or less, more preferably 28 nm or less, even more preferably. Is 25 nm or less, particularly preferably 20 nm or less. The particle diameter of a silica particle can select and combine arbitrary lower limits and an upper limit among these upper limits and the lower limits. When content of a silica particle is a numerical range of the said upper limit and / or a lower limit, in the transparent resin film in this invention, since it is hard to interact with the light of the specific wavelength in white light, the visibility of the said transparent resin film Can be suppressed. In this specification, the particle diameter of a silica particle shows an average primary particle diameter. The particle size of the silica particles in the transparent resin film can be measured by imaging using a transmission electron microscope (TEM). The particle diameter of the silica particle before producing a transparent resin film (for example, before adding to a varnish) can be measured with a laser diffraction type particle size distribution meter.

As a form of a silica particle, the silica sol in which the silica particle was disperse | distributed to the organic solvent etc., and the silica powder prepared by the vapor phase method are mentioned, for example. Among these, silica sol is preferable from the viewpoint of workability.

The silica particles may be subjected to a surface treatment, for example, silica particles substituted with a solvent (more specifically, gamma -butyrolactone) from a water-soluble alcohol dispersed silica sol. The water-soluble alcohol is an alcohol having 3 or less carbon atoms per hydroxyl group in one of the water-soluble alcohol molecules, and examples thereof include methanol, ethanol, 1-propanol, 2-propanol and the like. Although it depends on the phase property of a kind of a silica particle and a polyimide-type polymer, when a silica particle is surface-treated normally, compatibility with the polyimide-type polymer contained in a transparent resin film improves, and dispersibility of a silica particle is carried out. Since there exists a tendency to improve, the fall of the visibility of this invention can be suppressed.

(UV absorber)

The transparent resin film in this invention may further contain a ultraviolet absorber. For example, a triazine ultraviolet absorber, a benzophenone ultraviolet absorber, a benzotriazole ultraviolet absorber, a benzoate ultraviolet absorber, a cyanoacrylate ultraviolet absorber, etc. are mentioned. These may be used independently and may use 2 or more types together. Suitable commercially available ultraviolet absorbers include, for example, Sumisorb® 340 manufactured by Sumika Chemtex Company, Limited, Adekastab LA-31 manufactured by ADEKA Corporation, and TINUVIN (trademark) 1577 by BASF Japan Co., Ltd. is mentioned. Content of a ultraviolet absorber becomes like this. Preferably it is 1 phr or more and 10 phr or less, More preferably, it is 3 phr or more and 6 phr or less with respect to the mass of the transparent resin film in this invention.

(Whitening agent)

The transparent resin film in this invention may further contain a brightener. A brightener can be added, for example, in order to adjust a color sense, when additives other than a brightener are added. Examples of the brightener include monoazo dyes, triarylmethane dyes, phthalocyanine dyes, and anthraquinone dyes. Among these, anthraquinone dyes are preferable. Suitable commercially available brighteners include, for example, Macrorex® violet B manufactured by LANXESS, Sumplast® Violet B manufactured by Sumika Chemtex Co., Ltd. and Mitsubishi Chemical Co., Ltd. And diamond resin Blue G manufactured by Mitsubishi Chemical Corporation. These may be used independently and may use 2 or more types together. The content of the brightener is preferably 5 ppm or more and 40 ppm or less with respect to the mass of the transparent resin film in the present invention.

The use of the transparent resin film in this invention is not specifically limited, You may use for various uses. As described above, the transparent resin film may be a single layer or a laminate, the transparent resin film may be used as it is, or may be used as a laminate with another film. Since the said transparent resin film has the outstanding surface quality, it is useful as a transparent resin film in an image display apparatus etc.

The transparent resin film in this invention is useful as a front plate of an image display apparatus, especially a front plate (window film) of a flexible display. A flexible display has the flexible functional layer and the said polyimide type film superimposed on a flexible functional layer, and functions as a front plate, for example. That is, the front panel of the flexible display is arranged on the viewer side on the flexible functional layer. This front plate has a function of protecting the flexible functional layer.

[Method for producing transparent resin film]

Although the transparent resin film in this invention is not specifically limited, For example, the following processes:

(a) step (varnish preparation step) of preparing the liquid (henceforth, it may be described as varnish) containing the said resin and the said filler,

(b) applying the varnish to the substrate to form a coating film (coating step), and

(c) Process of drying apply | coated liquid (coating film) and forming transparent resin film (transparent resin film formation process)

It can manufacture by the method containing these.

In the varnish preparation step, the varnish is prepared by dissolving the resin in a solvent and adding and stirring the filler and other additives as necessary. In addition, when using silica as a filler, you may add the silica sol which substituted the dispersion liquid of the silica sol containing silica with the solvent which the said resin can melt | dissolve, for example, the solvent used for preparation of the following varnish, to resin.

The solvent used for preparation of the varnish is not particularly limited as long as the resin can be dissolved. As such a solvent, For example, amide solvents, such as N, N- dimethylacetamide (DMAc) and N, N- dimethylformamide; lactone solvents such as γ-butyrolactone (GBL) and γ-valerolactone; Sulfur-containing solvents such as dimethyl sulfone, dimethyl sulfoxide and sulfolane; Carbonate solvents such as ethylene carbonate and propylene carbonate; And combinations thereof. Among these, an amide solvent or a lactone solvent is preferable. These solvents can be used individually or in combination of 2 or more types. The varnish may also include water, an alcohol solvent, a ketone solvent, an acyclic ester solvent, an ether solvent, or the like. Solid content concentration of a varnish becomes like this. Preferably it is 1-25 mass%, More preferably, it is 5-20 mass%.

In a coating process, a varnish is apply | coated on a base material by a well-known coating method, and a coating film is formed. As a well-known coating method, for example, a roll coating method such as a wire bar coating method, a reverse coating, a gravure coating method, a die coating method, a comma coating method, a lip coating method, a screen coating method, a fountain coating method, a spray method, a flexible ( I) a molding method and the like.

In a transparent resin film formation process, a long strip-shaped transparent resin film can be formed by drying a coating film and peeling from a base material. You may perform the heat processing process which dries a transparent resin film further after peeling. The heat treatment of the coating film is usually performed at a temperature of 50 to 350 ° C, preferably 100 to 300 ° C. If necessary, the coating film may be dried under an inert atmosphere or a reduced pressure.

In heat processing, the both ends of an elongate strip | belt-shaped transparent resin film are respectively gripped, and the conveyed film is conveyed, the width of a gripped film is made into a predetermined distance, for example, heat processing is carried out, conveying in a dryer. At this time, the ratio of the width of the film after the heat treatment to the width of the film before the heat treatment is set to 1.1 or less, and the heat treatment of the transparent resin film can be performed by releasing the holding of the resin film from the dryer.

Gripping of a film is performed by using a some clip, for example. Alternatively, a pin can be used instead of the clip.

According to the size of the conveying apparatus, the plurality of clips can be fixed to an endless chain of a predetermined length, the chain moves at the same speed as the film, and the clips are installed at appropriate positions of the chain, and enter the dryer. The transparent resin film is gripped before, and the gripping is released at the time of leaving the dryer.

The clip and the endless chain are usually made of metal, and lubricating oil is used at the site where the metal parts are in contact with each other to reduce friction. The dynamic viscosity of the lubricant, in the 40 ℃, typically 100mm ² / s more than 800mm ² / s or less, preferably 100mm ² / s more than 800mm ² / s or less, more preferably 100mm ² / s more than 700mm ² / s or less , More preferably 100 mm ² / s or more and less than 700 mm ² / s, even more preferably 150 mm ² / s or more and 600 mm ² / s or less, particularly preferably 150 mm ² / s or more and less than 600 mm ² / s, particularly preferably it is 200mm ² / s more than 500mm ² / s or less, still more preferably 200mm ² / s more than 500mm ² / s or less.

As said lubricating oil, for example, Barrierta J400V (made by NOK Klubber Co., Ltd.), Daphne (registered trademark) oil CO100, 150, 220, 260 ( Idemitsu Kosan Co., Ltd.), S-3101, S-3103, S-3105, S-3230 (manufactured by MORESCO), Unister (registered trademark) H-481D , HR-170R, HR-200, H-609BR, C-3373A, C-400B, C-6910BE, and TOE-500 (manufactured by Nichi Corporation Co., Ltd.).

The plurality of clips provided at one end of the film is provided such that the space between the adjacent clips is, for example, 1 to 50 mm, preferably 3 to 25 mm, and more preferably 5 to 10 mm.

Moreover, when the straight line orthogonal to a film conveyance axis was matched with the grip part center of the arbitrary clip of one end of a film, the intersection of the said straight line and the other end of a film, and the distance of the grip part center of the clip closest to the said intersection is Preferably it is 3 mm or less, More preferably, it is 2 mm or less, More preferably, it can be set to 1 mm or less. By the said distance being in the said range, optical properties, for example in the left and right of a film, can be made homogeneous.

The conveyance speed of a film becomes like this. Preferably it is 0.1-15 m / min, More preferably, it is 0.1-10 m / min. When a conveyance speed exists in said range, the quality of the film obtained, for example, in-plane uniformity can be made favorable.

Examples of the base material include an endless belt made of SUS if the metal type, and a long band-shaped PET film, a PEN film, another polyimide resin or a polyamide resin film, a cycloolefin polymer (COP) film, an acrylic film, etc., if the resin is used. have. Especially, PET film, COP film, etc. are preferable from a viewpoint of the smoothness and heat resistance, and PET film is more preferable from a viewpoint of adhesiveness with a transparent resin film, and cost.

As for the raw material film, the weight reduction rate M over 120 degreeC to 250 degreeC calculated | required by thermogravimetry-differential heat measurement (it may be called "TG-DTA measurement" hereafter.), Preferably it is about 1 to 40% more, It is preferable that a part of the solvent is removed from the varnish so that it is preferably 3 to 20%, more preferably 5 to 15%, particularly preferably 5 to 12%. The weight reduction rate M of the raw material film can be measured by the following method using a commercially available TG-DTA measuring device. As a measuring apparatus of TG-DTA, TG / DTA6300 by Hitachi High-Tech Science Corporation can be used.

First, about 20 mg of sample is acquired from a raw material film, the sample is heated up to 120 degreeC at the temperature increase rate of 10 degree-C / min, it hold | maintains at 120 degreeC for 5 minutes, and then 10 degree-C / min to 400 degreeC The weight change of a sample is measured, heating on the condition of temperature rising at a temperature increase rate. Next, what is necessary is just to calculate the weight reduction rate M (%) from 120 degreeC to 250 degreeC from the result of TG-DTA measurement by a following formula. In the following expression, W ₀ represents the weight of the sample after the look out for 5 minutes at 120 ℃, W ₁ represents the weight of the sample in 250 ℃.

M (%) = 100- (W ₁ / W ₀ ) × 100

When the weight reduction rate M of the raw material film is somewhat large, when the raw material film is wound as a laminate with a substrate or a surface protective film, deformation such as bending of the laminate is suppressed and the winding property of the laminate is improved. There is this.

When the weight reduction rate M of a raw material film is small to some extent, when a raw material film is wound as a laminated body with a base material or a surface protection film, there exists a tendency for a raw material film to stick to a base material or a surface protection film. For this reason, a laminated body can be easily unwound from a roll, maintaining the uniform transparency of a raw material film.

<Protective film>

In this invention, a transparent resin film is good also as a laminated body including the protective film bonded together to the said transparent resin film. The protective film is bonded to the surface without a support of the transparent resin film. When winding up a laminated body in roll shape, when there exists a problem in winding properties, such as blocking, in addition to the above, you may bond a protective film to the surface on the opposite side to the transparent resin film of a support body. The protective film bonded to a transparent resin film is a film for temporarily protecting the surface of a transparent resin film, and is not specifically limited as long as it is a peelable film which can protect the surface of a transparent resin film. For example, Polyester resin films, such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; Polyolefin resin films, such as polyethylene and a polypropylene film, an acrylic resin film, etc. are mentioned, It is preferable to select from the group which consists of a polyolefin resin film, a polyethylene terephthalate resin film, and an acrylic resin film. When the protective film is bonded to both surfaces of a laminated body, the protective film of each surface may be mutually same or different.

Although the thickness of a protective film is not specifically limited, Usually, it is 10-100 micrometers, Preferably it is 10-80 micrometers. When the protective film is bonded to both surfaces of a laminated body, the thickness of the protective film of each surface may be same or different.

Laminate film roll

In this invention, the thing by which the said laminated body (support body, a transparent resin film, and a protective film as needed) were wound by roll shape in the core is called laminated film roll. In the continuous production, the laminated film roll is often stored in the form of a film roll once from space and other constraints, and the laminated film roll is one of them. In the form of a laminated film roll, since a laminated body is wound more strongly, the cloudy cause material on a support body becomes easy to be transferred on a transparent resin film. However, when the support body having the predetermined logarithmic contact angle of the present invention is used, the clouding material from the support is hard to be transferred to the transparent resin film, and even if it is wound with a laminate film roll, clouding is unlikely to occur.

As a material which comprises the core of a laminated film roll, a polyethylene resin, a polypropylene resin, a polyvinyl chloride resin, a polyester resin, an epoxy resin, a phenol resin, a melamine resin, a silicon resin, a polyurethane resin, a polycarbonate resin, for example Synthetic resins such as ABS resin; Metals such as aluminum; Fiber-reinforced plastics (FRP: a composite material in which fibers such as glass fibers are contained in plastics to improve strength); The core forms a cylindrical or cylindrical shape, and the diameter thereof is, for example, 80 to 170 mm. Moreover, although the diameter after winding a film roll is not specifically limited, Usually, it is 200-800 mm.

Moreover, after bonding a protective film to a transparent resin film, it can slit to a desired width.

<Flexible Image Display Device>

The present invention includes a flexible display device including the optical film. The optical film of the present invention is preferably used as a front plate in a flexible image display device, and the front plate may be called a window film. The said flexible image display apparatus consists of a laminated body for flexible image display apparatuses, and an organic electroluminescent display panel, The flexible image display apparatus laminated body is arrange | positioned at the visual recognition side with respect to an organic electroluminescent display panel, and is comprised so that it is bendable. As a laminated body for flexible image display apparatuses, you may further contain a polarizing plate and a touch sensor, and the lamination order is arbitrary, but in order of a window film, a polarizing plate, a touch sensor or a window film, a touch sensor, and a polarizing plate from a visual recognition side. It is preferable that they are laminated. When a polarizing plate exists in the visual recognition side rather than a touch sensor, since the pattern of a touch sensor becomes difficult to visually recognize and the visibility of a display image improves, it is preferable. Each member can be laminated | stacked using an adhesive agent, an adhesive, etc. The light shielding pattern may be provided on at least one surface of any one of the window film, the polarizing plate, and the touch sensor.

[Polarizing Plate]

As described above, the flexible display device of the present invention includes a polarizing plate, preferably a circular polarizing plate. A circular polarizing plate is a functional layer which has a function which transmits only a right circle or a left circle polarization component by laminating | stacking (lambda) / 4 phase (s) difference plate in a linear polarizing plate. For example, it is used to convert external light into right polarized light to block external light reflected by the organic EL panel and left circularly polarized light, and to suppress the influence of the reflected light by transmitting only the light emitting components of the organic EL to make the image easier to see. In order to achieve the circularly polarized light function, the absorption axis of the linear polarizing plate and the slow axis of the λ / 4 phase difference plate need to be 45 ° in theory, but are practically 45 ± 10 °. The linear polarizer and the λ / 4 retardation plate do not necessarily have to be stacked adjacent to each other, and the relationship between the absorption axis and the slow axis may satisfy the range described above. Although it is preferable to achieve complete circular polarization in all wavelengths, since it does not necessarily need to be the case in practical use, the circular polarizing plate in this invention also includes an elliptical polarizing plate. It is also preferable to improve the visibility in the state over polarized sunglasses by laminating | stacking (lambda) / 4 phase (s) difference film further on the visual recognition side of a linear polarizing plate, and making outgoing light circularly polarized.

The linear polarizing plate is a functional layer having a function of passing light that vibrates in the transmission axis direction but blocking polarization of a vibration component perpendicular to the linear polarizing plate. The linear polarizing plate may be a structure including a linear polarizer alone or a linear polarizer and a protective film attached to at least one surface thereof. The thickness of the linear polarizing plate may be 200 μm or less, and preferably 0.5 to 100 μm. When the thickness of a linear polarizing plate exists in the said range, it exists in the tendency for the flexibility of a linear polarizing plate to fall easily.

The linear polarizer may be a film polarizer produced by dyeing and stretching a polyvinyl alcohol (hereinafter sometimes abbreviated as PVA) -based film. A dichroic dye is oriented and the polarizing performance is exhibited by extending | stretching in the state which the dichroic dye, such as iodine, adsorbed or adsorb | sucked to PVA to the PVA system film oriented by extending | stretching. In manufacture of the said film polarizer, you may have other processes, such as swelling, bridge | crosslinking by boric acid, washing | cleaning by aqueous solution, and drying. The stretching or dyeing step may be performed by a PVA film alone, or may be performed in a state of being laminated with other films such as polyethylene terephthalate. Preferably the thickness of the PVA system film used is 10-100 micrometers, and the said draw ratio is 2-10 times preferably.

Moreover, as another example of the said polarizer, the liquid crystal coating type polarizer formed by apply | coating and forming a liquid crystal polarizing composition is mentioned. The liquid crystal polarizing composition may contain a liquid crystal compound and a dichroic dye compound. The said liquid crystalline compound should just have the property to show a liquid crystal state, and especially since it can exhibit high polarization performance, if it has high order orientation states, such as a smectic phase, it is preferable. Moreover, it is preferable that a liquid crystalline compound has a polymeric functional group.

The said dichroic dye compound is a pigment | dye which is oriented with the said liquid crystal compound and shows dichroism, may have a polymeric functional group, and the dichroic dye itself may have liquid crystallinity.

Any one of the compounds contained in the liquid crystal polarizing composition has a polymerizable functional group. The liquid crystal polarizing composition may further include an initiator, a solvent, a dispersant, a leveling agent, a stabilizer, a surfactant, a crosslinking agent, a silane coupling agent, and the like.

The said liquid crystal polarizing layer is manufactured by apply | coating a liquid crystal polarizing composition on an oriented film, and forming a liquid crystal polarizing layer. The liquid crystal polarizing layer can form a thickness thin compared with a film polarizer, Preferably the thickness is 0.5-10 micrometers, More preferably, it is 1-5 micrometers.

The said oriented film is manufactured by apply | coating an oriented film formation composition on a base material, for example, and providing orientation by rubbing, polarized light irradiation, etc. The alignment film forming composition contains an alignment agent, and may further include a solvent, a crosslinking agent, an initiator, a dispersant, a leveling agent, a silane coupling agent, and the like. As said aligning agent, polyvinyl alcohol, polyacrylate, polyamic acid, polyimide is mentioned, for example. When using the aligning agent which provides orientation by polarized light irradiation, it is preferable to use the aligning agent containing a cinnamate group. The weight average molecular weight of the polymer used as the aligning agent is, for example, about 10,000 to 1,000,000. The thickness of the alignment film is preferably 5 to 10,000 nm, and more preferably 10 to 500 nm in that the orientation regulation force is sufficiently expressed.

The liquid crystal polarizing layer may be peeled off from the substrate, transferred, and laminated, or the substrate may be laminated as it is. It is also preferable that the said base material plays a role as a transparent base material of a protective film, retardation plate, and a window film.

As said protective film, what is necessary is just a transparent polymer film, and the thing similar to the material and additive used for the transparent base material of the said window film can be used. Moreover, the coating type protective film obtained by apply | coating and hardening radical curable compositions, such as a cation hardening composition, such as an epoxy resin, and an acrylate, may be sufficient. The protective film may contain a plasticizer, an ultraviolet absorber, an infrared absorber, a colorant such as a pigment or a dye, a fluorescent brightener, a dispersant, a heat stabilizer, an optical stabilizer, an antistatic agent, an antioxidant, a lubricant, a solvent, and the like, as necessary. . The thickness of the said protective film becomes like this. Preferably it is 200 micrometers or less, More preferably, it is 1-100 micrometers. When the thickness of a protective film exists in said range, there exists a tendency for the flexibility of the said film to fall easily.

The (lambda) / 4 phase difference plate is a film which gives a phase difference of (lambda) / 4 in the direction orthogonal to the advancing direction of incident light (in-plane direction of a film). The lambda / 4 phase difference plate may be a stretchable phase difference plate produced by stretching a polymer film such as a cellulose film, an olefin film, a polycarbonate film. The λ / 4 retardation plate may be a phase difference regulator, a plasticizer, an ultraviolet absorber, an infrared absorber, a colorant such as a pigment or a dye, a fluorescent brightener, a dispersant, a heat stabilizer, an optical stabilizer, an antistatic agent, an antioxidant, a lubricant, a solvent, and the like. Etc. may be included.

The thickness of the stretched retardation plate is preferably 200 μm or less, and more preferably 1 to 100 μm. When the thickness of the stretchable retardation plate is in the above range, the flexibility of the stretched retardation plate tends to be less likely to be lowered.

Moreover, as another example of the said (lambda) / 4 phase (s) difference plate, the liquid crystal coating type phase difference plate formed by apply | coating and forming a liquid crystal composition is mentioned.

The liquid crystal composition contains a liquid crystal compound exhibiting liquid crystal states such as nematic, cholesteric and smectic. The liquid crystal compound has a polymerizable functional group.

The liquid crystal composition may further include an initiator, a solvent, a dispersant, a leveling agent, a stabilizer, a surfactant, a crosslinking agent, a silane coupling agent, and the like.

The said liquid crystal coating type phase difference plate can be manufactured similarly to the said liquid crystal polarizing layer by apply | coating and hardening a liquid crystal composition on a base, and forming a liquid crystal phase difference layer. The liquid crystal coating retardation plate can be formed thinner than the stretchable retardation plate. Preferably the thickness of the said liquid crystal polarizing layer is 0.5-10 micrometers, More preferably, it is 1-5 micrometers.

The liquid crystal coating type retardation plate may be peeled from the substrate, transferred, and laminated, or the substrate may be laminated as it is. It is also preferable that the said base material plays a role as a transparent base material of a protective film, retardation plate, and a window film.

In general, the shorter the wavelength, the larger the birefringence, and the longer the wavelength, the more material exhibits the small birefringence. In this case, since the phase difference of lambda / 4 cannot be achieved in the entire visible light region, the in-plane phase difference is preferably 100 to 180 nm, more preferably 130 to 150 nm so that the lambda / 4 is around 560 nm with high visibility. It is designed to be. The reverse dispersion (lambda) / 4 phase (s) difference plate using the material which has a birefringence wavelength dispersion characteristic opposite to the normal is preferable at the point which visibility becomes favorable. As such a material, for example, an extension type retardation plate can be used as described in JP 2007-232873 and the like, and the liquid crystal coating retardation plate can be used in JP 2010-30979 A and the like.

Moreover, as another method, the technique of obtaining a wideband (lambda) / 4 phase difference plate by combining with a (lambda) / 2 phase difference plate is also known (for example, Unexamined-Japanese-Patent No. 10-90521 etc.). The lambda / 2 phase difference plate is also produced by the same material method as the lambda / 4 phase difference plate. Although the combination of an extending | stretching retardation plate and a liquid crystal coating type retardation plate is arbitrary, both can make thickness thin by using a liquid crystal coating type retardation plate.

In order to improve the visibility of a diagonal direction, the said circularly polarizing plate is known by laminating | stacking a positive C plate (for example, Unexamined-Japanese-Patent No. 2014-224837 etc.). The positive C plate may be a liquid crystal coating type retardation plate or a stretched retardation plate. The phase difference in the thickness direction of the retardation plate is preferably -200 to -20 nm, more preferably -140 to -40 nm.

[Touch sensor]

It is preferable that the flexible display device of this invention is equipped with a touch sensor as mentioned above. The touch sensor is used as an input means. As a touch sensor, various forms, such as a resistive film system, a surface acoustic wave system, an infrared system, an electromagnetic induction system, and a capacitive system, are mentioned, Preferably, a capacitive system is mentioned.

The capacitive touch sensor is divided into an active region and an inactive region located at an outer portion of the active region. The active area is an area corresponding to an area (display) where a screen is displayed on the display panel. The active area is an area where a user's touch is detected. The inactive area is an area corresponding to an area (non-display area) where a screen is not displayed on the display device. . The touch sensor includes a substrate having a flexible characteristic, a sensing pattern formed in an active region of the substrate, and each sensing line formed in an inactive region of the substrate and connected to an external driving circuit through the sensing pattern and the pad unit. can do. As the substrate having the flexible characteristic, the same material as that of the transparent substrate of the window film can be used.

The sensing pattern may include a first pattern formed in a first direction and a second pattern formed in a second direction. The first pattern and the second pattern are arranged in different directions. The first pattern and the second pattern are formed on the same layer, and each pattern must be electrically connected to sense a touched point. Although the first pattern has a form in which a plurality of unit patterns are connected to each other through a seam, the second pattern has a structure in which a plurality of unit patterns are separated from each other in an island form, so that a separate bridge is used to electrically connect the second pattern. An electrode is needed. A well-known transparent electrode can be applied to the electrode for connection of a 2nd pattern. Examples of the material for the transparent electrode include indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc tin oxide (IZTO), indium gallium zinc oxide (IGZO), and cadmium tin oxide ( CTO), PEDOT (poly (3,4-ethylenedioxythiophene)), carbon nanotubes (CNT), graphene, metal wires, and the like, and preferably ITO. These can be used individually or in mixture of 2 or more types. The metal used for a metal wire is not specifically limited, For example, silver, gold, aluminum, copper, iron, nickel, titanium, selenium, chromium, etc. are mentioned, These can be used individually or in mixture of 2 or more types. .

The bridge electrode may be formed on the insulating layer on the sensing pattern, the bridge electrode is formed on the substrate, and the insulating layer and the sensing pattern may be formed thereon. The bridge electrode may be formed of a material such as a sensing pattern, or may be formed of molybdenum, silver, aluminum, copper, palladium, gold, platinum, zinc, tin, titanium, or an alloy of two or more thereof.

Since the first pattern and the second pattern should be electrically insulated, an insulating layer is formed between the sensing pattern and the bridge electrode. The insulating layer may be formed only between the seam and the bridge electrode of the first pattern, or may be formed as a layer covering the entire sensing pattern. In the case of the layer covering the entire sensing pattern, the bridge electrode may connect the second pattern through the contact hole formed in the insulating layer.

The touch sensor measures a difference in light transmittance caused by a difference in transmittance between a pattern region in which a sensing pattern is formed and a non-pattern region in which a sensing pattern is not formed, specifically, a difference in refractive index in these regions. As a means for properly compensating, an optical control layer may further be included between the substrate and the electrode. The optical control layer may include an inorganic insulating material or an organic insulating material. The optical control layer may be formed by coating a photocurable composition including a photocurable organic binder and a solvent on a substrate. The photocurable composition may further include inorganic particles. By the said inorganic particle, the refractive index of an optical adjusting layer can be made high.

The photocurable organic binder may include a copolymer of each monomer such as, for example, an acrylate monomer, a styrene monomer, a carboxylic acid monomer, and the like within a range that does not impair the effects of the present invention. The said photocurable organic binder may be a copolymer containing each different repeating unit, such as an epoxy group containing repeating unit, an acrylate repeating unit, and a carboxylic acid repeating unit, for example.

As said inorganic particle, a zirconia particle, a titania particle, an alumina particle, etc. are mentioned, for example.

The said photocuring composition may further contain each additive, such as a photoinitiator, a polymerizable monomer, and a hardening adjuvant.

[Adhesive layer]

Each layer (window film, circular polarizing plate, touch sensor) which forms the said laminated body for flexible image display apparatuses, and the film member (linear polarizing plate, (lambda) / 4 phase (s) difference plate, etc.) which comprise each layer can be bonded by an adhesive agent. Examples of the adhesive include an aqueous adhesive, an aqueous solvent volatilized adhesive, an organic solvent, a solvent-free adhesive, a solid adhesive, a solvent volatilized adhesive, a moisture curable adhesive, a heat curable adhesive, an anaerobic curing type, an active energy ray curable adhesive, a curing agent mixed adhesive, Commonly used adhesives such as hot melt adhesives, pressure sensitive adhesives (adhesives), re-wetting adhesives, and the like can be used, and preferably aqueous solvent volatilized adhesives, active energy ray-curable adhesives, and adhesives can be used. The thickness of an adhesive bond layer can be adjusted suitably according to the adhesive force requested | required etc., Preferably it is 0.01-500 micrometers, More preferably, it is 0.1-300 micrometers. Although the some adhesive layer exists in the said laminated body for flexible image display apparatuses, each thickness and kind may be same or different.

As the aqueous solvent volatilized adhesive, a polymer in an aqueous dispersion state such as a polyvinyl alcohol polymer, a water-soluble polymer such as starch, an ethylene-vinyl acetate emulsion, a styrene-butadiene emulsion, or the like can be used as the main polymer. In addition to the said main polymer and water, you may mix | blend a crosslinking agent, a silane compound, an ionic compound, a crosslinking catalyst, antioxidant, dye, a pigment, an inorganic filler, an organic solvent, etc. In the case of adhering with the aqueous solvent volatilized adhesive, the aqueous solvent volatilized adhesive may be injected between the adhered layers to bond the adhered layer, and then adhesiveness may be imparted by drying. When using the said aqueous solvent volatilization adhesive agent, the thickness of the contact bonding layer becomes like this. Preferably it is 0.01-10 micrometers, More preferably, it is 0.1-1 micrometer. When using the said aqueous solvent volatilization type adhesive in multiple layers, the thickness and kind of each layer may be same or different.

The said active energy ray hardening-type adhesive agent can be formed by hardening of the active energy ray hardening composition containing the reactive material which irradiates an active energy ray and forms an adhesive bond layer. The said active energy ray hardening composition can contain the at least 1 sort (s) of polymer of the radically polymerizable compound and cationic polymerizable compound similar to what is contained in a hard-coat composition. As the radically polymerizable compound, a compound similar to the radically polymerizable compound in the hard coat composition can be used.

As the cationically polymerizable compound, a compound similar to the cationically polymerizable compound in the hard coat composition can be used.

As a cationically polymerizable compound used for an active energy ray hardening composition, an epoxy compound is especially preferable. It is also preferable to include a monofunctional compound as a reactive diluent in order to lower the viscosity as an adhesive composition.

The active energy ray composition may contain a monofunctional compound in order to lower the viscosity. As said monofunctional compound, the compound which has one (meth) acryloyl group in one molecule, and one epoxy group or oxetanyl group in one molecule, for example, glycidyl (meth) acryl The rate etc. are mentioned.

The active energy ray composition may further contain a polymerization initiator. Examples of the polymerization initiator include radical polymerization initiators, cationic polymerization initiators, radicals and cationic polymerization initiators, and these may be appropriately selected and used. These polymerization initiators are decomposed by at least one of active energy ray irradiation and heating to generate radicals or cations to advance radical polymerization and cation polymerization. In the description regarding the hard coat composition, an initiator capable of initiating at least one of radical polymerization or cationic polymerization by active energy ray irradiation can be used.

The active energy ray curable composition may further include an ion trapping agent, an antioxidant, a chain transfer agent, an adhesion imparting agent, a thermoplastic resin, a filler, a fluid viscosity modifier, a plasticizer, an antifoaming agent, an additive, and a solvent. In the case of bonding two layers to be bonded by the active energy ray-curable adhesive, the active energy ray-curing composition is applied to any one or both of the layers to be bonded, and then bonded, and the active energy is applied to any one or both layers. It can bond by irradiating and hardening a line | wire. When using the said active energy ray hardening-type adhesive agent, the thickness of the contact bonding layer becomes like this. Preferably it is 0.01-20 micrometers, More preferably, it is 0.1-10 micrometers. When using the said active energy ray hardening-type adhesive agent for formation of several adhesive layer, the thickness and kind of each layer may be same or different.

As the pressure-sensitive adhesive, depending on the main polymer, it may be classified into an acrylic pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, a rubber pressure-sensitive adhesive, a silicone pressure-sensitive adhesive, and the like, and any of them may be used. In addition to a main polymer, you may mix | blend a crosslinking agent, a silane compound, an ionic compound, a crosslinking catalyst, antioxidant, a tackifier, a plasticizer, a dye, a pigment, an inorganic filler, etc. to an adhesive. The adhesive layer adhesive layer is formed by melt | dissolving and disperse | distributing each component which comprises the said adhesive in a solvent, obtaining an adhesive composition, and apply | coating this adhesive composition on a base material, and drying. The pressure-sensitive adhesive layer may be formed directly or may transfer what is formed on another substrate. In order to cover the adhesive surface before adhesion, it is also preferable to use a release film. When using the said active energy ray hardening-type adhesive agent, the thickness of this adhesive layer becomes like this. Preferably it is 0.1-500 micrometers, More preferably, it is 1-300 micrometers. When using more than one layer of the said adhesive, the thickness and kind of each layer may be same or different.

[Shading Pattern]

The light shielding pattern can be applied as at least a part of the bezel or the housing of the flexible image display device. The visibility of an image improves by making the wiring arrange | positioned at the edge part of the said flexible image display apparatus hidden by a light shielding pattern, and making it hard to see. The light shielding pattern may be in the form of a single layer or a multilayer. The color of the light shielding pattern is not particularly limited and may be various colors such as black, white, and metal. The light shielding pattern may be formed of a pigment for realizing color, and a polymer such as an acrylic resin, an ester resin, an epoxy resin, polyurethane, or silicone. You may use these individually or in mixture of 2 or more types. The light shielding pattern can be formed by various methods such as printing, lithography, inkjet, and the like. The thickness of the light shielding pattern is preferably 1 to 100 µm, and more preferably 2 to 50 µm. Moreover, it is also preferable to provide shapes, such as an inclination, in the thickness direction of a light shielding pattern.

Example

Hereinafter, the effect of this invention is made clear by an Example. In addition, this invention is not limited to a following example, It can change suitably in the range which does not change the summary, and can carry out.

Production Example 1: Production of Polyimide Resin (1)

A flask equipped with a silica gel tube, a stirring device, and a thermometer, and an oil bath were prepared in the separable flask. In this flask, 75.6 g of 4,4 '-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) and 2,2'-bis (trifluoromethyl) -4,4'-diaminodiphenyl ( TFMB) 54.5g. While stirring this at 400 rpm, 530 g of N, N-dimethylacetamide (DMAc) was added, and stirring was continued until the contents of the flask became a uniform solution. Subsequently, stirring was further continued for 20 hours, and the reaction was made to produce a polyamic acid while adjusting the temperature in a container to be in the range of 20-30 degreeC using an oil bath. After 30 minutes, the stirring speed was changed to 100 rpm. After stirring for 20 hours, the reaction system temperature was returned to room temperature, and 650 g of DMAc was added to adjust the polymer concentration to 10 mass%. Furthermore, 32.3 g of pyridine and 41.7 g of acetic anhydride were added, and the mixture was stirred at room temperature for 10.5 hours to perform imidization. The polyimide varnish was taken out from the reaction vessel. The obtained polyimide varnish was dripped in methanol, reprecipitation was carried out, the obtained powder was heat-dried, the solvent was removed, and the polyimide resin (1) was obtained as solid content. GPC measurement was performed on the obtained polyimide resin (1), and the weight average molecular weight was 365,000. Moreover, the imidation ratio of polyimide resin (1) was 99.0%. In the same manner, polyimide resin (1) was obtained in large quantities.

<Measurement of imidation ratio>

The imidation ratio of the polyimide resin obtained above was calculated based on the signal derived from the partial structure shown by following formula (chemical formula XXX) from the ¹ H-NMR measurement result. Measurement conditions and a calculation method are as follows.

(Measurement conditions of NMR)

Measuring Device: Bruker 600MHz NMR Device AVANCE600

Sample temperature: 303 K

Measuring method: ¹ H-NMR, HSQC

(Calculation method of imidation ratio of polyimide resin)

In the ¹ H-NMR spectrum obtained by using a solution containing a polyimide resin as the measurement sample, the integral value of the signal derived from proton (A) in the formula (XXX) is a signal derived from Int _A and proton (B). The integral value of was set to Int _B. From these values, the imidation ratio (%) was calculated | required by the following formula (NMR-1).

Production Example 2: Preparation of Polyimide Resin (2)

In a nitrogen gas atmosphere, TFMB 45g (140.52 mmol) and 768.55 g of DMAc were added to a 1 L separable flask equipped with stirring blades, and TFMB was dissolved in DMAc while stirring at room temperature. Next, 18.92 g (42.58 mmol) of 6FDA was added to the flask, followed by stirring at room temperature for 3 hours. Thereafter, 4.19 g (14.19 mmol) of 4,4'-oxybis (benzoyl chloride) (OBBC), and then 17.29 g (85.16 mmol) of terephthaloyl chloride (TPC) were added to the flask and stirred at room temperature for 1 hour. Subsequently, 4.63 g (49.68 mmol) of 4-methylpyridine and 13.04 g (127.75 mmol) of acetic anhydride were added to the flask, and the mixture was stirred at room temperature for 30 minutes. A reaction solution was obtained.

The obtained reaction solution was cooled to room temperature, poured into a large amount of methanol in a yarn form, and the precipitate deposited was taken out, and after immersing in methanol for 6 hours, the mixture was washed with methanol. Next, the precipitate was dried under reduced pressure at 100 ° C to obtain a polyimide resin (2). The weight average molecular weight of the polyimide resin (2) was 455,000. Moreover, the imidation ratio of polyimide resin (2) was 98.9%. In the same manner, polyimide resin (2) was obtained in large quantities.

Production Example 3: Preparation of Dispersion 1

Methanol dispersion organic-ized silica (average primary particle diameter: 27 nm measured by BET method) was substituted by (gamma) -butyrolactone (GBL), and GBL dispersion organic-ized silica (solid content 30.3 mass%) was obtained. This dispersion is referred to as dispersion 1.

Production Example 4: Production of Varnish (1)

Varnish 1 had the composition shown in Table 1, melt | dissolved a polymer in the solvent, the solid content computed from the introduction amount is 15.5%, and obtained the varnish (1) whose viscosity in 25 degreeC is 36,500 cps.

Production Example 5: Preparation of Varnish (2)

Varnish 2 is mixed with a GBL solvent at room temperature such that the composition ratio of polymer and filler is 60:40, and Sumisorb 340 (UVA) and Sumiplast Violet B (BA) are added in an amount of 5.7 phr or 35 ppm based on the total mass of the polymer and silica. It was added so that it was stirred and stirred until uniform. Varnish (2) which is 10.3 mass% of solid content and the viscosity of 38,500 cps in 25 degreeC was obtained.

Production Example 6: Film Formation of Raw Material Film 1

The varnish (1) was placed on a PET (polyethylene terephthalate) film ("Cosmoshine (registered trademark) A4100" made by TOYOBO CO., LTD.), A film thickness of 188 µm, and a film thickness distribution of ± 2 µm. The coating film was molded by casting molding. At this time, the line speed was 0.4 m / min, and heated at 70 ° C. for 8 minutes, then heated at 100 ° C. for 10 minutes, then heated at 90 ° C. for 8 minutes, and finally dried at 80 ° C. for 8 minutes. did. Then, the coating film was peeled off from PET film, and the raw material film 1 of thickness 86micrometer and width 700mm was obtained. The mass reduction rate M of the raw material film 1 was 9.6%.

Production Example 7: Film Formation of Raw Material Film 2

The varnish 2 was molded by casting on the PET (polyethylene terephthalate) film (Toyobo Co., Ltd. "Cosmoshine A4100", film thickness of 188 micrometers, film thickness distribution +/- 2 micrometers). At this time, the ship speed was 0.3 m / min. Moreover, after heating at 80 degreeC for 10 minutes, it heated at 100 degreeC for 10 minutes, then heated at 90 degreeC for 10 minutes, and finally dried the coating film on the conditions heated at 80 degreeC for 10 minutes. Then, the coating film was peeled off from PET film and the raw material film 2 of thickness 58micrometer and width 700mm was obtained. The mass reduction rate M of the raw material film 2 was 9.2%.

Example 1: Preparation of Resin Film

The solvent was removed using the tenter type dryer (1-6 chamber structure) which used the raw material film 1 obtained by the manufacture example 6 as a holding | gripping tool, and the polyimide film 1 with a thickness of 79 micrometers was obtained. At that time, the temperature in the dryer was set to 200 ° C, and the ratio between the clip holding width 25 mm, the conveying speed of the film 1.1 m / min, the film width at the dryer inlet (the distance between the clips) and the film width at the dryer outlet was set to 1.0, Moreover, the process was performed to the film conveyance rail of a tenter using lubricating oil NOK Klubber Co., Ltd. and Barrierta J400V. After the film was separated from the clip, the clip portion was slit, the PET protective film was bonded to the film, and then wound on a 6-inch core made of ABS to obtain a roll film. Table 2 shows the appearance of the film after leaving the tenter dryer and the residual solvent amount of the obtained polyimide film.

<Kinematic viscosity measurement>

The kinematic viscosity was measured at 40 ° C by the method described in JIS Z 8803: 2011.

<Scattering distance measurement>

From a height of 600 mm on the PET film, one drop of lubricating oil was dropped five times from a 5 cc eyedropper, the distance from the center of the droplet where the oil was most scattered from the dropping point center was measured, and the average distance was calculated.

<Lubricant contamination of film>

The surface of the obtained film was irradiated with Polarion Light ("PS-X1" (3,400 lumens), manufactured by Polarion) from the flow direction (ie, longitudinal direction). At that time, it irradiated with the angle lying about 20-70 degrees with respect to the film surface. The direction to visually recognize was almost immediately above (the angle of 90 degrees from a resin film surface) of the surface of the resin film to evaluate, visually evaluated, and identified the contamination point. IR measurement of the contaminated point was performed to determine that 0 / m ² was good in the detected number of used lubricant oils, to be ○, 1 to 5 / m ² was judged to be slightly good, and to be △, and 6 or more / m ² was determined to be defective and x was obtained.

Example 2: Preparation of Resin Film

Except having used the raw material film 2 obtained by the manufacture example 7, the film conveyance speed was 2.7 m / min, and the ratio of the film width (distance between clips) of a dryer inlet and the film width of a dryer exit was 0.98, In the same manner, a polyamideimide-based film 1 having a thickness of 49.5 µm was obtained. In that case, the external appearance of the film after leaving a tenter type dryer, and the residual solvent amount of the obtained polyamide-imide-type film 1 are shown in Table 2.

Comparative Example 1: Preparation of Resin Film

A polyamide having a thickness of 49 μm was obtained from the raw material film 2 in the same manner as in Example 2, except that the lubricating oil was changed to Varierta J100V (manufactured by NOK Clubber Co., Ltd.) and the conveyance speed was changed to 0.9 m / min. Mid film 2 was obtained. In that case, the external appearance of the film after leaving a tenter type dryer, and the residual solvent amount of the obtained polyamide-imide-type film 2 are shown in Table 2.

Comparative Example 2: Production of Resin Film

A polyamide-imide film 3 having a thickness of 50 μm was obtained from the raw film 2 in the same manner as in Comparative Example 1 except that the lubricating oil was changed to UCON (registered trademark) 50HB-5100 (manufactured by Dow Chemical Company). In that case, the external appearance of the film after leaving a tenter type dryer, and the residual solvent amount of the obtained polyamide-imide-type film 3 are shown in Table 2. Since the viscosity of lubricating oil was high, lubricating oil generate | occur | produced, the viscosity fall occurred and film contamination was confirmed.

Example 3: Preparation of Resin Film

Polyamide-imide film 4 was obtained in the same manner as in Example 2 except that Unister (registered trademark) H-609BR (manufactured by Nichi Oil Co., Ltd.) was used as the lubricating oil. In that case, the external appearance of the film after leaving a tenter type dryer, and the residual solvent amount of the obtained polyamide-imide-type film 4 are shown in Table 2.

(a) Side view, (b) Top view, (1) 1 room, (2) 2 rooms, (3) 3 rooms, (4) 4 rooms, (5) 5 rooms, (6) 6 rooms

Claims (9)

At least 1 sort (s) of resin chosen from the group which consists of polyimide-type resin and polyamide-type resin, and the elongate transparent resin film which consists of 0.1-30 mass% organic solvent with respect to the mass of a transparent resin film,
When the member which has the resin film holding part holding the edge part of the said transparent resin film, the drive metal chain part driven by the metal sprocket, and the metal bearing part which changes the position of the resin film holding part along a metal rail is used as a clip chain. As a manufacturing method of the film which heat-processes, conveying the said transparent resin film in the tenter type dryer which has the clip chain group which consists of several clip chains in the both ends of a transparent resin film, respectively,
The manufacturing method of the transparent resin film made to lubricate the contact part of this metal component using lubricating oil whose kinematic viscosity in 40 degreeC is 100 mm <^2> / s or more and 800 mm <^2> / s or less. The method of claim 1,
The said kinematic viscosity is 100 mm <^2> / s or more and less than 800 mm <^2> / s. The method according to claim 1 or 2,
The said kinematic viscosity is 400 mm <^2> / s or more and 500 mm <^2> / s or less, The manufacturing method. The method according to claim 1 or 2,
The manufacturing method whose temperature of heat processing is 50-350 degreeC. The method according to claim 1 or 2,
The manufacturing method whose conveyance speed of a transparent resin film is 0.1-15 m / min. The light is irradiated at an angle of 20 to 70 ° with respect to the resin film surface, visually identified from an angle of 90 ° from the resin film surface, the contamination point is identified, IR measurement of the contamination point is performed, and the number of detection of the used lubricant oil is 0. Resin film of pieces / m ² or 1 to 5 pieces / m ² . The flexible display device provided with the resin film of Claim 6. The method of claim 7, wherein
Furthermore, the flexible display apparatus provided with a touch sensor. The method according to claim 7 or 8,
Furthermore, the flexible display apparatus provided with a polarizing plate.

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