JP2011152693A - Resin film substrate and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin film substrate and a method for manufacturing the resin film substrate maintaining flexibility while improving the crack resistance and durability of gas barrier properties of a gas barrier layer by improving adhesiveness between the gas barrier layer and a support body. <P>SOLUTION: The resin film substrate includes the gas barrier layer provided on the support body. The support body contains thermoplastic resin and micro fibrillated cellulose, and the gas barrier layer contains an inorganic oxide formed from a ceramic precursor. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a resin film substrate having gas barrier properties and flexibility, and a method for producing the same.

  Conventionally, a glass substrate has been used as a support substrate in flat panel displays and organic thin film devices typified by liquid crystal displays, but in recent years there has been a demand for thinner, lighter, and more flexible shapes. Instead of the substrate, a light and flexible film substrate has been studied. However, the resin substrate has a problem that the gas barrier property is insufficient.

  For example, in the technique disclosed in Patent Document 1, the barrier property is secured by laminating thin glass, but since the adhesive is interposed, cracking of the thin glass occurs due to the expansion of the adhesive layer. Therefore, there is a problem that the flatness and the barrier property are remarkably deteriorated.

  In the technique disclosed in Patent Document 2, a microfibrillated cellulose (hereinafter abbreviated as “MFC” where appropriate) is impregnated with glass. However, since the support includes glass, a glass substrate is used. There is a problem that flexibility is lost as in the case of using.

JP 2008-242154 A JP 2009-194039 A

  The present invention has been made in view of the above-mentioned problems and situations, and the solution is to improve the adhesion between the gas barrier layer and the support, thereby improving the crack resistance and durability of the gas barrier property of the gas barrier layer. It is providing the resin film board | substrate which improved the property and maintained the flexibility, and its manufacturing method.

  The present inventors have examined means for improving the crack resistance and gas barrier durability of the gas barrier layer by improving the adhesion between the gas barrier layer and the support from the background of the background art. In other words, as described in the background art above, the deterioration of the barrier property is durable because a fine crack or misalignment occurs in the gas barrier layer of an inorganic oxide such as thin glass due to expansion and contraction due to heat of the resin substrate. Estimated to be inferior.

  Accordingly, the present inventors have improved the durability of the inorganic oxide by adding a thermoplastic resin and microfibrillated cellulose to the support so that the thermal stability of the resin film substrate is obtained, and the like, like a thin film glass. In addition, the present inventors have found that durability, which is a problem specific to a gas barrier layer that is weak against expansion, can be maintained. In addition, the hydrogen bond between the hydroxyl group of the ceramic precursor such as polysilazane and the hydroxyl group of the microfibrillated cellulose has an effect of being able to cope with the stress when bent and maintaining flexibility.

  Therefore, the above-mentioned problem according to the present invention is solved by the following means.

  1. A resin film substrate having a gas barrier layer provided on a support, the support containing a thermoplastic resin and microfibrillated cellulose, and the gas barrier layer containing an inorganic oxide formed from a ceramic precursor A resin film substrate.

  2. 2. The resin film substrate according to item 1, wherein the thermoplastic resin is a resin selected from a cellulose ester resin, a polycarbonate resin, an acrylic resin, and a polyolefin resin.

  3. 3. The resin film substrate according to item 1 or 2, wherein the ceramic precursor contains polysilazane.

  4). It is a manufacturing method of the resin film board | substrate which manufactures the resin film board | substrate as described in any one of said 1st term | claim-3rd, Comprising: At least (1) The ceramic precursor which forms an inorganic oxide film by heating And (2) a step of locally heating the coating film of the ceramic precursor to form an inorganic oxide, and a method of manufacturing a resin film substrate.

  By the above-mentioned means of the present invention, by providing improved adhesion between the gas barrier layer and the support, the resin film substrate having improved crack resistance and gas barrier durability of the gas barrier layer and maintaining flexibility is provided. can do. Moreover, the manufacturing method of the said film substrate can be provided.

Outline flow sheet showing one embodiment of manufacturing apparatus for thermoplastic resin support

  The resin film substrate of the present invention is a resin film substrate in which a gas barrier layer is provided on a support, the support contains a thermoplastic resin and microfibrillated cellulose, and the gas barrier layer is made of a ceramic precursor. It contains the formed inorganic oxide. This feature is a technical feature common to the inventions according to claims 1 to 4.

  As an embodiment of the present invention, it is preferable that the thermoplastic resin is a resin selected from a cellulose ester resin, a polycarbonate resin, an acrylic resin, and a polyolefin resin from the viewpoint of manifesting the effects of the present invention. Moreover, it is preferable that the ceramic precursor contains polysilazane.

  The production method of the resin film substrate for producing the resin film substrate of the present invention includes at least (1) a step of applying a ceramic precursor that forms an inorganic oxide film by heating, and (2) application of the ceramic precursor. It is preferable that the production method has a step of locally heating the film to form an inorganic oxide.

  Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail.

<Gas barrier layer>
The gas barrier layer according to the present invention is characterized by containing an inorganic oxide formed from a ceramic precursor.

As the ceramic precursor, polysilazane, aluminum isopropoxide Al (OPr-i) ₃ , zinc propoxide Zn (OPr) ₂ , tetraethoxysilane Si (OEt) ₄ , titanium isopropoxide Ti (OPr-i) ₄ A metal alkoxide such as can be used.

In the present invention, it is particularly preferable to use polysilazane. Here, the “polysilazane” is a polymer having a silicon-nitrogen bond, such as SiO _{2 made of} Si—N, Si—H, N—H, etc., Si ₃ N ₄ and both intermediate solid solutions SiO _x N _y etc. It is a ceramic precursor inorganic polymer.

When the ceramic precursor contains polysilazane, the support (resin substrate) is coated with a solution containing a catalyst in the polysilazane represented by the following formula (I) and an organic solvent as necessary, and The solvent is removed by evaporation, thereby leaving a polysilazane layer having a layer thickness of 0.05 to 3.0 μm on the support (resin substrate) and oxygen, active oxygen, In some cases, it is preferable to employ a method of forming a glass-like transparent film on the support (resin substrate) by locally heating the polysilazane layer in the presence of nitrogen. .
Formula (I):-(SiR ₁ R ₂ -NR ₃ ) _n-
[Wherein R ₁ , R ₂ , and R ₃ are the same or different and independently of each other, hydrogen, or an optionally substituted alkyl group, aryl group, vinyl group, or (trialkoxysilyl) alkyl group Preferably from hydrogen, methyl, ethyl, propyl, iso-propyl, butyl, iso-butyl, tert-butyl, phenyl, vinyl or 3- (triethoxysilyl) propyl, 3- (trimethoxysilylpropyl) Represents a selected group, where n is an integer and n is defined such that the polysilazane has a number average molecular weight of 150 to 150,000 g / mol. ]
As catalysts, preferably basic catalysts, in particular N, N-diethylethanolamine, N, N-dimethylethanolamine, triethanolamine, triethylamine, 3-morpholinopropylamine or N-heterocyclic compounds are used. . The catalyst concentration is usually in the range of 0.1 to 10 mol%, preferably 0.5 to 7 mol%, based on polysilazane.

In one of the preferred embodiments, a solution containing perhydropolysilazane in which all of R ₁ , R ₂ and R ₃ are hydrogen atoms is used.

In yet another preferred embodiment, the coating according to the invention comprises at least one polysilazane of the formula (II)
Formula _{(II) :-( SiR 1 R 2} -NR 3) n - (SiR 4 R 5 -NR 6) p -
In which R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are independently of each other hydrogen, or optionally substituted alkyl, aryl, vinyl, or (trialkoxysilyl) Represents an alkyl group, where n and p are integers, and n is determined such that the polysilazane has a number average molecular weight of 150 to 150,000 g / mol.

Particularly preferred are compounds wherein R ₁ , R ₃ and R ₆ represent hydrogen and R ₂ , R ₄ and R ₅ represent methyl, R ₁ , R ₃ and R ₆ represent hydrogen and R ₂ , A compound in which R ₄ represents methyl and R ₅ represents vinyl, R ₁ , R ₃ , R ₄ and R ₆ represent hydrogen and R ₂ and R ₅ represent methyl.

A solution containing at least one polysilazane represented by the following formula (III) is also preferable.
Formula _{(III) :-( SiR 1 R 2} -NR 3) n - (SiR 4 R 5 -NR 6) p - (SiR 7 R 8 -NR 9) q -
In the above formula, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ and R ₉ are independently of one another hydrogen or optionally substituted alkyl group, aryl Represents a group, a vinyl group or a (trialkoxysilyl) alkyl group, where n, p and q are integers, and n is such that the polysilazane has a number average molecular weight of 150 to 150,000 g / mol. Determined.

Particularly preferred are R ₁ , R ₃ and R ₆ represent hydrogen and R ₂ , R ₄ , R ₅ and R ₈ represent methyl, R ₉ represents (triethoxysilyl) propyl and R ₇ Is a compound in which represents alkyl or hydrogen.

  The ratio of polysilazane in the solvent is generally 1 to 80% by mass of polysilazane, preferably 5 to 50% by mass, and particularly preferably 10 to 40% by mass.

  As the solvent, in particular, an aprotic solvent which does not contain water and a reactive group (for example, hydroxyl group or amine group) and is inert to polysilazane, preferably an aprotic solvent is suitable. This includes, for example, aliphatic or aromatic hydrocarbons, halogen hydrocarbons, esters such as ethyl acetate or butyl acetate, ketones such as acetone or methyl ethyl ketone, ethers such as tetrahydrofuran or dibutyl ether, and mono and polyalkylene glycol dialkyl ethers ( Diglymes) or a mixture of these solvents.

  An additional component of the polysilazane solution can be a further binder such as those conventionally used in the manufacture of paints. For example, cellulose ethers and cellulose esters such as ethyl cellulose, nitrocellulose, cellulose acetate or cellulose acetobutyrate, natural resins such as rubber or rosin resins, synthetic resins such as polymerized resins or condensed resins such as aminoplasts, in particular Urea resins and melamine formaldehyde resins, alkyd resins, acrylic resins, polyesters or modified polyesters, epoxides, polyisocyanates or blocked polyisocyanates, or polysiloxanes.

The polysilazane further components of the formulation, for example, the viscosity of the formulation, wetting the underlying film-forming property, additives influencing the lubrication or exhaust resistance, or inorganic nanoparticles, for example SiO _2, TiO _2, It can be ZnO, ZrO ₂ or Al ₂ O ₃ .

  By using the method of the present invention, it is possible to produce a dense and highly adherent glass-like layer having excellent barrier action against gas because there are no cracks and holes.

  The thickness of the film to be formed is preferably in the range of 100 nm to 2 μm.

The resin film substrate of the present invention has a water vapor transmission rate of 0.1 g / m ² · 24 hr or less, preferably 0.01 g / m ² · 24 hr or less, more preferably 0.001 g / m ² as gas barrier performance. -Adjust with a gas barrier layer so that it may be 24 hours or less.

The oxygen permeability is 0.1 ml / m ² · 24 h · atm or less, preferably 0.001 ml / m ² · 24 h · atm, more preferably 0.001 ml / m ² · 24 h · atm or less. Adjust by gas barrier layer.

The water vapor transmission rate (g / m ² / day) is measured by the method described in JIS K 7129B. For the measurement, for example, a water vapor transmission rate measuring device PERMATRAN-W 3/33 MG module manufactured by MOCON can be used.

Similarly, the oxygen transmission rate (ml / m ² / day / atm) can be measured according to JIS K 7126B using, for example, an oxygen transmission rate measuring device OX-TRAN 2/21 ML module manufactured by MOCON. it can.

<Microfibrillated cellulose>
As the microfibrillated cellulose that can be used in the present invention, microfibrillated cellulose (MFC) obtained by defibrating cellulose fibers with a high-pressure shearing force as fine cellulose having a fiber diameter of 1 μm or less can be used. In the present invention, it is particularly preferable to use so-called cellulose nanofibers.

  The cellulose nanofiber according to the present invention refers to a cellulose-based fiber having an average fiber diameter of 4 to 200 nm as a fiber. The fibers may be composed of single fibers that are sufficiently spaced and so as to enter each other. In this case, the average fiber diameter is the average diameter of single fibers. Further, the fibers according to the present invention may be one in which a plurality of (may be many) single fibers are gathered in a bundle to form one yarn. The average fiber diameter is defined as the average value of the diameter of one yarn.

  The average fiber diameter of the fiber used in the present invention is preferably 4 to 100 nm, more preferably 4 to 60 nm.

  In addition, as long as the fiber used by this invention has an average fiber diameter in the range of 4-200 nm, the thing of the fiber diameter out of the range of 4-200 nm may be contained in the fiber, The ratio is 30. Preferably, the fiber diameter of all the fibers is 200 nm or less, particularly 100 nm or less, particularly 60 nm or less.

  The length of the fiber is not particularly limited, but the average length is preferably 100 nm or more. If the average length of the fibers is shorter than 100 nm, the reinforcing effect is low, and the strength of the fiber-reinforced composite material may be insufficient. In addition, although a fiber length less than 100 nm may be contained in the fiber, it is preferable that the ratio is 30 mass% or less.

  The measurement of the said fiber diameter and fiber length can be measured with a commercially available microscope and an electron microscope. For example, by taking a photograph of cellulose nanofibers magnified 2000 times with a scanning electron microscope, and then analyzing the photographic image using “SCANNING IMAGE ANALYZER” (manufactured by JEOL Ltd.) based on this photograph It was measured. Under the present circumstances, the average value of a fiber diameter and fiber length can be calculated | required using 100 cellulose nanofibers.

  Cellulosic fibers refer to cellulose microfibrils constituting the basic skeleton of plant cell walls or the like, or constituent fibers thereof, and are usually aggregates of unit fibers having a fiber diameter of about 4 nm. In order to obtain high strength and low thermal expansion, it is preferable that this cellulose fiber contains a crystal structure of 40% or more.

  The cellulose nanofiber according to the present invention can be obtained, for example, by the method described in JP-A-2005-60680 and JP-A-2008-1728.

  The cellulose nanofibers of the present invention are preferably refined using a plurality of pulverizing means. Although the pulverizing means is not limited, in order to finely pulverize to a particle size suitable for the purpose of the present invention, there is a method that can obtain a strong shearing force such as a high-pressure homogenizer, a media mill, a grindstone rotary grinder, and a stone mill grinder. Preferably used.

  A high-pressure homogenizer is a device that grinds by shear force due to accelerated high flow velocity, rapid pressure drop (cavitation), and impact force caused by high-velocity particles colliding face-to-face within a fine orifice, and is commercially available. As the device, a nanomizer (manufactured by Nanomizer Co., Ltd.), a microfluidizer (manufactured by Microfluidics) or the like can be used.

The degree of cellulose fibrillation and homogenization by the high-pressure homogenizer depends on the pressure fed to the high-pressure homogenizer and the number of passes (number of passes) passed through the high-pressure homogenizer. The pumping pressure is usually in the range of about 500 to 2000 kg / cm ^2, which is suitable for ultrafine processing, but 1000 to 2000 kg / cm ² is more preferable in consideration of productivity. The number of passes is, for example, about 5 to 50 times, preferably about 10 to 40 times, particularly about 20 to 30 times. The medium mill is a wet vibration mill, a wet planetary vibration mill, a wet ball mill, a wet roll mill, a wet coball mill, a wet bead mill, a wet paint shaker, or the like. Among these, for example, a wet bead mill is a device in which a metal or ceramic medium is built in a container and this is subjected to wet grinding by forcibly stirring it. A mill (manufactured by Kotobuki Giken Kogyo Co., Ltd.), a pearl mill (manufactured by Ashizawa Co., Ltd.), a dyno mill (manufactured by Shinmaru Enterprises Co., Ltd.), or the like can be used.

  The grindstone rotary grinder is a kind of colloid mill or stone mortar grinder, for example, grinds a grindstone made of abrasive grains having a particle size of 16 to 120 and passes the above-mentioned aqueous dispersion through the grinder. That is, it is an apparatus to be pulverized. You may perform a process in multiple times as needed. It is one of the preferred embodiments that the grindstone is appropriately changed. The grindstone rotary crusher has both “short fiber” and “fine” actions, but the action is affected by the grain size of the abrasive grains. For the purpose of shortening the fiber length, a # 46 or less grindstone is effective. For miniaturization purposes, a # 46 or greater grindstone is effective. No. 46 has both functions. Specific examples of the apparatus include a pure fine mill (grinder mill) (Kurita Machinery Co., Ltd.), a serendipeater, a super mass collider, and a super grinder (above, Masuko Sangyo Co., Ltd.).

  In the present invention, the obtained cellulose nanofibers are added to the thermoplastic resin directly or as a dispersion, and the content thereof is preferably in the range of 0.1 to 50% by mass. More preferably, it is 5-50 mass%, and especially 10-40 mass% is preferable.

  Although the method for containing cellulose nanofibers in acetylated cellulose is not particularly limited, it is preferably contained as a dispersion when preparing a dope solution in the solution casting method described below.

(Support)
The resin film substrate of the present invention is characterized by using a thermoplastic resin support containing a thermoplastic resin as a main constituent material of the support.

  Here, the “thermoplastic resin” refers to a resin that becomes soft when heated to a glass transition temperature or a melting point and can be molded into a desired shape.

  General thermoplastic resins include cellulose esters, polyethylene (PE), high density polyethylene, medium density polyethylene, low density polyethylene, polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene chloride, polystyrene. (PS), polyvinyl acetate (PVAc), Teflon (registered trademark) (polytetrafluoroethylene, PTFE), ABS resin (acrylonitrile butadiene styrene resin), AS resin, acrylic resin (PMMA), or the like can be used.

  When strength and resistance to breakage are particularly required, polyamide (PA), nylon, polyacetal (POM), polycarbonate (PC), modified polyphenylene ether (m-PPE, modified PPE, PPO), polybutylene terephthalate (PBT) ), Polyethylene terephthalate (PET), glass fiber reinforced polyethylene terephthalate (GF-PET), cyclic polyolefin (COP), and the like.

  When higher heat distortion temperature and long-term use characteristics are required, polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), polysulfone, polyethersulfone, amorphous polyarylate, liquid crystal polymer, polyetherether A ketone, thermoplastic polyimide (PI), polyamideimide (PAI), or the like can be used.

  In the present invention, from the viewpoint of manifesting the effects of the present invention, the thermoplastic resin is preferably a resin selected from a cellulose ester resin, a polycarbonate resin, an acrylic resin, and a polyolefin resin.

  The elongation at break in at least one direction of the thermoplastic resin support is preferably 10% or more, more preferably 20% or more in the measurement based on JIS-K7127-1999.

  The thickness of the support is preferably 20 μm or more. More preferably, it is 30 μm or more.

  The upper limit of the thickness is not particularly limited, but in the case of forming a film by a solution casting method, the upper limit is about 250 μm from the viewpoint of applicability, foaming, solvent drying, and the like. In addition, the thickness of a film can be suitably selected according to a use.

  The support preferably has a total light transmittance of 90% or more, more preferably 93% or more. Moreover, as a realistic upper limit, it is about 99%. In order to achieve excellent transparency expressed by such total light transmittance, it is necessary not to introduce additives and copolymerization components that absorb visible light, or to remove foreign substances in the polymer by high-precision filtration. It is effective to reduce the diffusion and absorption of light inside the film.

  Hereinafter, a particularly preferred resin in the present invention will be described in detail.

<Cellulose ester resin>
The cellulose ester resin that can be used in the present invention is selected from cellulose (di, tri) acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate phthalate, and cellulose phthalate. It is preferable that there is at least one.

  Among these, particularly preferable cellulose esters include cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, and cellulose acetate butyrate.

  As the substitution degree of the mixed fatty acid ester, more preferable cellulose acetate propionate and lower fatty acid ester of cellulose acetate butyrate have an acyl group having 2 to 4 carbon atoms as a substituent, and the substitution degree of an acetyl group is X. When the substitution degree of propionyl group or butyryl group is Y, it is preferably a cellulose resin containing a cellulose ester that simultaneously satisfies the following formulas (I) and (II).

Formula (I) 2.6 ≦ X + Y ≦ 3.0
Formula (II) 1.0 ≦ X ≦ 2.5
Of these, cellulose acetate propionate is particularly preferably used. Among them, 1.9 ≦ X ≦ 2.5 and 0.1 ≦ Y ≦ 0.9 are preferable. The part not substituted with the acyl group is usually present as a hydroxyl group. These can be synthesized by known methods.

  Furthermore, the cellulose ester used in the present invention preferably has a weight average molecular weight Mw / number average molecular weight Mn ratio of 1.5 to 5.5, particularly preferably 2.0 to 5.0, Preferably it is 2.5-5.0, More preferably, the cellulose ester of 3.0-5.0 is used preferably.

  The cellulose ester raw material cellulose used in the present invention may be wood pulp or cotton linter, and the wood pulp may be softwood or hardwood, but softwood is more preferred. A cotton linter is preferably used from the viewpoint of peelability during film formation. The cellulose ester made from these can be mixed suitably or can be used independently.

  For example, the ratio of cellulose ester derived from cellulose linter: cellulose ester derived from wood pulp (coniferous): cellulose ester derived from wood pulp (hardwood) is 100: 0: 0, 90: 10: 0, 85: 15: 0, 50:50: 0, 20: 80: 0, 10: 90: 0, 0: 100: 0, 0: 0: 100, 80:10:10, 85: 0: 15, 40:30:30.

  In the present invention, 1 g of cellulose ester resin is added to 20 ml of pure water (electric conductivity 0.1 μS / cm or less, pH 6.8), and the pH is 6 when stirred in a nitrogen atmosphere at 25 ° C. for 1 hr. It is preferable that the electric conductivity is 1 to 100 μS / cm.

<Polycarbonate resin>
In the present invention, various known polycarbonate resins can also be used. In the present invention, it is particularly preferable to use an aromatic polycarbonate. There is no restriction | limiting in particular about the said aromatic polycarbonate, and there will be no restriction | limiting in particular if it is an aromatic polycarbonate from which the various characteristics of a desired film are acquired.

  In general, a polymer material collectively referred to as polycarbonate is a generic term for a polymer material in which a polycondensation reaction is used in its synthesis method and the main chain is linked by a carbonic acid bond. , Phosgene, diphenyl carbonate and the like obtained by polycondensation. Usually, an aromatic polycarbonate represented by a repeating unit having 2,2-bis (4-hydroxyphenyl) propane called bisphenol-A as a bisphenol component is preferably selected, and various bisphenol derivatives should be appropriately selected. Thus, an aromatic polycarbonate copolymer can be constituted.

  In addition to this bisphenol-A, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 9,9-bis (4-hydroxyphenyl) fluorene, 1,1 -Bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxyphenyl) -2-phenyl Ethane, 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane, bis (4-hydroxyphenyl) diphenylmethane, bis (4-hydroxyphenyl) sulfide, bis ( 4-hydroxyphenyl) sulfone, 1,1-bis (4-hydroxyphenyl) -3,3,5-tri Mention may be made of a chill cyclohexane, and the like.

  It is also possible to use an aromatic polyester carbonate partially containing a terephthalic acid and / or isophthalic acid component. By using such a structural unit as a part of the structural component of the aromatic polycarbonate composed of bisphenol-A, the properties of the aromatic polycarbonate, such as heat resistance and solubility, can be improved. The present invention is also effective for coalescence.

  If the aromatic polycarbonate used here has a viscosity average molecular weight of 10,000 or more and 200,000 or less, it is suitably used. A viscosity average molecular weight of 20,000 to 120,000 is particularly preferred. If a resin having a viscosity average molecular weight lower than 10,000 is used, the mechanical strength of the resulting film may be insufficient, and if it has a high molecular weight of 400000 or more, the viscosity of the dope becomes too large, causing problems in handling. The viscosity average molecular weight can be measured by commercially available high performance liquid chromatography.

  The glass transition temperature of the aromatic polycarbonate according to the present invention is preferably 200 ° C. or higher in order to obtain a highly heat-resistant film, and more preferably 230 ° C. or higher. These can be obtained by appropriately selecting the copolymerization component. The glass transition temperature can be measured with a DSC apparatus (differential scanning calorimetric analyzer). For example, the baseline is unevenly determined by a temperature rising condition of 10 ° C./min with RDC220 manufactured by Seiko Instruments Inc. It is the temperature that begins to do.

  In the present invention, the solvent used in the dope composition containing the aromatic polycarbonate is a mixed solvent containing 4 to 14 parts by mass of methylene chloride and a linear or branched aliphatic alcohol having 1 to 6 carbon atoms. It is preferable.

  The amount of the linear or branched aliphatic alcohol having 1 to 6 carbon atoms is preferably 4 to 12 parts by mass. Using such a mixed solvent, by peeling the web with a higher residual solvent concentration than conventional, it is possible to suppress the generation of strong static electricity at the time of web peeling, thereby damaging the belt, film streaks and unevenness, The generation of minute scratches can be prevented.

  The type of alcohol added is limited by the solvent used. It is a necessary condition that the alcohol and the solvent are compatible. These may be added alone or in combination of two or more. The alcohol in the present invention is preferably a linear or branched aliphatic alcohol having 1 to 6, preferably 1 to 4, more preferably 2 to 4 carbon atoms. Specific examples include methanol, ethanol, isopropanol, and tert-butanol. Of these, ethanol, isopropanol, and tertiary-butanol can achieve almost the same effect, but methanol has a slightly lower effect. Although the reason is not clear, it is presumed that the boiling point of the solvent, that is, the ease of flying during drying is related. Higher alcohols higher than that are not preferred because they have a high boiling point and are likely to remain after film formation.

  The amount of alcohol added must be carefully selected. These alcohols are completely poor in solubility in aromatic polycarbonate and are completely poor solvents. Therefore, it cannot be added too much, and should be the minimum amount that provides satisfactory peelability. As mentioned above, it is 4-14 mass parts with respect to a methylene chloride, Preferably it is 4-12 mass parts. When the addition amount is in the range of 4 to 14 parts by mass with respect to the amount of methylene chloride, the solubility of the solvent in the polymer and the dope stability are improved, and the effect of improving the peelability is increased.

  The present invention comprises the above methylene chloride and aliphatic alcohol in the dope composition, but other solvents can also be used. The remaining solvent is not particularly limited as long as it dissolves the aromatic polycarbonate at a high concentration and is compatible with alcohol, and further has a low boiling point. For example, as a solvent having a solubility in an aromatic polycarbonate, in addition to methylene chloride, halogen solvents such as chloroform, 1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene, 1,3-dioxolane, 1, Examples include cyclic ether solvents such as 4-dioxane and tetrahydrofuran, and ketone solvents such as cyclohexanone.

  When using other solvent, there is no limitation in particular and it may use it in consideration of an effect. The effects here include mixing the solvent without sacrificing solubility and stability, for example, improving the surface properties of the film formed by the solution casting method (leveling effect), evaporation rate and system These include viscosity adjustment and crystallization suppression effects. What is necessary is just to determine the kind and addition amount of the solvent to mix by the degree of these effects, and you may use 1 type (s) or 2 or more types as a solvent to mix.

  Other solvents preferably used include halogen solvents such as chloroform and 1,2-dichloroethane, hydrocarbon solvents such as toluene and xylene, ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone, and ethyl acetate and butyl acetate. Examples include ester solvents, ether solvents such as ethylene glycol dimethyl ether and methoxyethyl acetate.

  The dope composition according to the present invention may be prepared by any method as long as a transparent solution having a low haze is obtained as a result. A predetermined amount of alcohol may be added to the aromatic polycarbonate solution dissolved in a certain solvent in advance, or the aromatic polycarbonate may be dissolved in a mixed solvent containing alcohol. However, as described above, since alcohol is a poor solvent, the method of adding the latter after the former may cause clouding of the dope due to the precipitation of the polymer. Therefore, the method of dissolving in the latter mixed solvent is preferable.

<acrylic resin>
The acrylic resin that can be used in the present invention includes a methacrylic resin. Although it does not restrict | limit especially as resin, What consists of 50-99 mass% of methyl methacrylate units and 1-50 mass% of other monomer units copolymerizable with this is preferable.

  Other monomers that can be copolymerized include alkyl methacrylates having 2 to 18 carbon atoms, alkyl acrylates having 1 to 18 carbon atoms, acrylic acid, methacrylic acid, and the like. Saturated acids, maleic acids, fumaric acids, unsaturated divalent carboxylic acids such as itaconic acid, aromatic vinyl compounds such as styrene, α-methylstyrene, and nucleus-substituted styrene, α, β- such as acrylonitrile, methacrylonitrile, etc. Examples thereof include unsaturated nitrile, maleic anhydride, maleimide, N-substituted maleimide, glutaric anhydride, and the like. These may be used alone or in combination of two or more.

  Among these, methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, s-butyl acrylate, 2-ethylhexyl acrylate, and the like are preferable from the viewpoint of thermal decomposition resistance and fluidity of the copolymer. n-Butyl acrylate is particularly preferably used.

  The acrylic resin preferably has a weight average molecular weight (Mw) of 80000 to 1000000 from the viewpoint of mechanical strength as a film and fluidity when producing the film. With this molecular weight, both heat resistance and brittleness can be achieved.

  The weight average molecular weight of a resin such as an acrylic resin can be measured by gel permeation chromatography. The measurement conditions are as follows.

Solvent: Methylene chloride Column: Shodex K806, K805, K803G (Used by connecting three Showa Denko Co., Ltd.)
Column temperature: 25 ° C
Sample concentration: 0.1% by mass
Detector: RI Model 504 (manufactured by GL Sciences)
Pump: L6000 (manufactured by Hitachi, Ltd.)
Flow rate: 1.0ml / min
Calibration curve: Standard polystyrene STK standard polystyrene (manufactured by Tosoh Corp.) Mw = 2,800,000-500 calibration curves with 13 samples were used. The 13 samples are preferably used at approximately equal intervals.

  There is no restriction | limiting in particular as a manufacturing method of an acrylic resin, You may use any well-known methods, such as suspension polymerization, emulsion polymerization, block polymerization, or solution polymerization. Here, as a polymerization initiator, a normal peroxide type and an azo type can be used, and a redox type can also be used. Regarding the polymerization temperature, suspension or emulsion polymerization may be performed at 30 to 100 ° C, and bulk or solution polymerization may be performed at 80 to 160 ° C. Furthermore, in order to control the reduced viscosity of the produced copolymer, polymerization can be carried out using alkyl mercaptan or the like as a chain transfer agent.

  A commercially available thing can also be used as an acrylic resin. For example, Delpet 60N, 80N (Asahi Kasei Chemicals Co., Ltd.), Dianal BR52, BR80, BR83, BR85, BR88 (Mitsubishi Rayon Co., Ltd.), KT75 (Denki Kagaku Kogyo Co., Ltd.) and the like can be mentioned. .

<Polyolefin resin>
In the present invention, it is also preferable to use polyethylene or the following cyclic olefin.

  Examples of the cyclic olefin resin include norbornene resins, monocyclic olefin resins, cyclic conjugated diene resins, vinyl alicyclic hydrocarbon resins, and hydrides thereof. Among these, norbornene-based resins can be suitably used because of their good transparency and moldability.

  Examples of the norbornene-based resin include a ring-opening polymer of a monomer having a norbornene structure, a ring-opening copolymer of a monomer having a norbornene structure and another monomer, a hydride thereof, and a norbornene structure. An addition polymer of a monomer having a monomer, an addition copolymer of a monomer having a norbornene structure and another monomer, or a hydride thereof.

  Among these, a ring-opening (co) polymer hydride of a monomer having a norbornene structure is particularly suitable from the viewpoints of transparency, moldability, heat resistance, low hygroscopicity, dimensional stability, lightness, and the like. Can be used.

Examples of the monomer having a norbornene structure include bicyclo [2.2.1] hept-2-ene (common name: norbornene) and tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene. (Common name: dicyclopentadiene), 7,8-benzotricyclo [4.3.0.1 ^2,5 ] dec-3-ene (common name: methanotetrahydrofluorene), tetracyclo [4.4.0. 1 ^2,5 . ^{17, 10} ] dodec-3-ene (common name: tetracyclododecene), and derivatives of these compounds (for example, those having a substituent in the ring). Here, examples of the substituent include an alkyl group, an alkylene group, and a polar group. Moreover, these substituents may be the same or different and a plurality may be bonded to the ring. Monomers having a norbornene structure can be used singly or in combination of two or more.

  Examples of the polar group include a hetero atom or an atomic group having a hetero atom. Examples of the hetero atom include an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, and a halogen atom. Specific examples of the polar group include a carboxyl group, a carbonyloxycarbonyl group, an epoxy group, a hydroxyl group, an oxy group, an ester group, a silanol group, a silyl group, an amino group, a nitrile group, and a sulfone group.

  Other monomers capable of ring-opening copolymerization with monomers having a norbornene structure include monocyclic olefins such as cyclohexene, cycloheptene, and cyclooctene and derivatives thereof, cyclic conjugated dienes such as cyclohexadiene, cycloheptadiene, and the like. And derivatives thereof.

  A ring-opening polymer of a monomer having a norbornene structure and a ring-opening copolymer of a monomer having a norbornene structure and another monomer copolymerizable with the monomer have a known ring-opening polymerization catalyst. It can be obtained by (co) polymerization in the presence.

  Examples of other monomers that can be addition copolymerized with a monomer having a norbornene structure include α-olefins having 2 to 20 carbon atoms such as ethylene, propylene, and 1-butene, and derivatives thereof; cyclobutene, cyclopentene, And cycloolefins such as cyclohexene and derivatives thereof; non-conjugated dienes such as 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, and the like. These monomers can be used alone or in combination of two or more. Among these, α-olefin is preferable and ethylene is more preferable.

  An addition polymer of a monomer having a norbornene structure and an addition copolymer of a monomer having a norbornene structure with another monomer copolymerizable with a monomer having a norbornene structure are prepared in the presence of a known addition polymerization catalyst. It can be obtained by polymerization.

  A hydrogenated product of a ring-opening polymer of a monomer having a norbornene structure, a hydrogenated product of a ring-opening copolymer of a monomer having a norbornene structure and another monomer capable of ring-opening copolymerization thereof, Hydrogenated products of addition polymers of monomers having a norbornene structure, and hydrogenated products of addition copolymers of monomers having a norbornene structure and other monomers capable of addition copolymerization with these A known hydrogenation catalyst containing a transition metal such as nickel or palladium is added to the polymer solution, and the carbon-carbon unsaturated bond is preferably hydrogenated by 90% or more.

Among norbornene-based resins, as repeating units, X: bicyclo [3.3.0] octane-2,4-diyl-ethylene structure and Y: tricyclo [4.3.0.1 ^2,5 ] decane-7 , 9-diyl-ethylene structure, the content of these repeating units is 90% by mass or more based on the entire repeating units of the norbornene resin, and the content ratio of X and the content ratio of Y The ratio of X: Y is preferably 100: 0 to 40:60. By using such a resin, it is possible to obtain an optical film that has no dimensional change in the long term and is excellent in stability of optical characteristics.

  The molecular weight of the cyclic olefin resin used in the present invention is appropriately selected according to the purpose of use. Polyisoprene or polystyrene-converted weight average molecular weight (Mw) measured by gel permeation chromatography using cyclohexane (toluene if the polymer resin does not dissolve) as a solvent, usually 20,000 to 150,000. . Preferably it is 25,000-100,000, More preferably, it is 30,000-80,000. When the weight average molecular weight is in such a range, the mechanical strength and moldability of the film are highly balanced and suitable.

  The glass transition temperature of the cyclic olefin resin may be appropriately selected according to the purpose of use. From the viewpoint of durability and stretchability, it is preferably in the range of 130 to 160 ° C, more preferably 135 to 150 ° C.

  The molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) of the cyclic olefin resin is 1.2 to 3.5, preferably 1.5 to 3.0, from the viewpoint of relaxation time, productivity, and the like. More preferably, it is 1.8 to 2.7.

The cyclic olefin resin used in the present invention preferably has an absolute value of photoelastic coefficient of 10 × 10 ⁻¹² Pa ⁻¹ or less, more preferably 7 × 10 ⁻¹² Pa ⁻¹ or less, and more preferably 4 × 10. It is particularly preferably ⁻¹² Pa ⁻¹ or less. The photoelastic coefficient C is a value represented by C = Δn / σ where birefringence is Δn and stress is σ.

  In the present invention, it is preferable that the cyclic olefin resin does not substantially contain particles. Here, “substantially free of particles” means that even if particles are added to a film made of a cyclic olefin resin, the amount of increase in haze from the non-added state is allowed to be in the range of 0.05% or less. Means you can. In particular, the alicyclic polyolefin resin lacks affinity with many organic particles and inorganic particles. Therefore, when a cyclic olefin resin film to which particles exceeding the above range are added is stretched, voids are easily generated, and as a result, There is a risk that a significant decrease in haze occurs.

(Production method of resin support)
As a method for producing a resin support according to the present invention (hereinafter also simply referred to as “support”), the usual inflation method, T-die method, calendar method, cutting method, casting method, emulsion method, hot press A production method such as a method can be used, but a solution casting method by a casting method and a melt casting method are preferable from the viewpoints of suppressing coloring, suppressing defects of foreign matters, and suppressing optical defects such as die lines.

  Hereinafter, a typical manufacturing method will be described in detail.

<Method for producing resin substrate by solution casting method>
(Organic solvent)
When the support according to the present invention is produced by the solution casting method, the organic solvent useful for forming the dope is not limited as long as it dissolves a thermoplastic resin such as acrylic resin, cellulose ester resin, and polycarbonate. Can be used.

  For example, as the chlorinated organic solvent, methylene chloride, as the non-chlorinated organic solvent, methyl acetate, ethyl acetate, amyl acetate, acetone, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2,2,3,3-hexafluoro-1-propanol, 1,3-difluoro-2-propanol, 1,1,1,3,3,3-hexafluoro- 2-methyl-2-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2,2,3,3,3-pentafluoro-1-propanol, nitroethane, ethyl lactate, lactic acid , Diacetone alcohol and the like, methylene chloride, methyl acetate, ethyl acetate, acetone, ethyl lactate and the like are preferably used. That.

  In addition to the organic solvent, the dope may contain 1 to 40% by mass of a linear or branched aliphatic alcohol having 1 to 4 carbon atoms. When the proportion of alcohol in the dope increases, the web gels, facilitating peeling from the metal support, and when the proportion of alcohol is small, the dissolution of the thermoplastic resin in a non-chlorine organic solvent system is promoted. There is also a role.

  In particular, the thermoplastic resin should be a dope composition in which at least 10 to 45 mass% of the thermoplastic resin is dissolved in methylene chloride and a solvent containing a linear or branched aliphatic alcohol having 1 to 4 carbon atoms. preferable.

  Examples of the linear or branched aliphatic alcohol having 1 to 4 carbon atoms include methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, and tert-butanol. Ethanol is preferred because of the stability of these dopes, the relatively low boiling point, and good drying properties.

  Hereinafter, a preferred method for forming a film-like resin substrate (hereinafter also simply referred to as “film”) according to the present invention will be described.

1) Dissolution Step In this step, a thermoplastic resin, microfibrillated cellulose, and other additives are dissolved in an organic solvent mainly composed of a good solvent for the thermoplastic resin while stirring in a dissolution vessel to form a dope.

  For the dissolution of the thermoplastic resin, a method carried out at normal pressure, a method carried out below the boiling point of the main solvent, a method carried out under pressure above the boiling point of the main solvent, JP-A-9-95544, JP-A-9-95557 Alternatively, various dissolution methods such as a cooling dissolution method as described in JP-A-9-95538 and a high-pressure method as described in JP-A-11-21379 can be used. The method of pressurizing at a boiling point or higher is preferred.

  Recycled material is a finely pulverized film, which is generated when the film is formed, cut off on both sides of the film, or the original film that has been speculated out due to scratches, etc. Reused.

2) Casting process An endless metal belt, such as a stainless steel belt or a rotating metal drum, which supports the dope is fed to a pressure die through a liquid feed pump (for example, a pressurized metering gear pump) and supported infinitely. This is a step of casting a dope from a pressure die slit to a casting position on the body.

  A pressure die that can adjust the slit shape of the die base portion and can easily make the film thickness uniform is preferable. Examples of the pressure die include a coat hanger die and a T die, and any of them is preferably used. The surface of the metal support is a mirror surface. In order to increase the film forming speed, two or more pressure dies may be provided on the metal support, and the dope amount may be divided and stacked. Or it is also preferable to obtain the film of a laminated structure by the co-casting method which casts several dope simultaneously.

3) Solvent evaporation step In this step, the web (the dope is cast on the casting support and the formed dope film is called a web) is heated on the casting support to evaporate the solvent.

  To evaporate the solvent, there are a method of blowing air from the web side and / or a method of transferring heat from the back side of the support by a liquid, a method of transferring heat from the front and back by radiant heat, and the like. High efficiency and preferable. A method of combining them is also preferably used. The web on the support after casting is preferably dried on the support in an atmosphere of 40 to 100 ° C. In order to maintain the atmosphere at 40 to 100 ° C., it is preferable to apply hot air at this temperature to the upper surface of the web or to heat by means such as infrared rays.

  From the viewpoint of surface quality, moisture permeability, and peelability, it is preferable to peel the web from the support within 30 to 120 seconds.

4) Peeling process It is the process of peeling the web which the solvent evaporated on the metal support body in a peeling position. The peeled web is sent to the next process.

  The temperature at the peeling position on the metal support is preferably 10 to 40 ° C, more preferably 11 to 30 ° C.

  In addition, it is preferable that the residual solvent amount at the time of peeling of the web on the metal support at the time of peeling is peeled in the range of 50 to 120% by mass depending on the strength of drying conditions, the length of the metal support, and the like. If the web is peeled off at a time when the amount of residual solvent is larger, if the web is too soft, the flatness at the time of peeling will be lost, and slippage and vertical stripes are likely to occur due to the peeling tension. The amount of solvent is determined.

  The residual solvent amount of the web is defined by the following formula.

Residual solvent amount (%) = (mass before web heat treatment−mass after web heat treatment) / (mass after web heat treatment) × 100
Note that the heat treatment for measuring the residual solvent amount represents performing heat treatment at 115 ° C. for 1 hour.

  The peeling tension at the time of peeling the metal support and the film is usually 196 to 245 N / m. However, when wrinkles easily occur at the time of peeling, it is preferable to peel with a tension of 190 N / m or less. It is preferable to peel at a minimum tension that can be peeled to 166.6 N / m, and then peel at a minimum tension to 137.2 N / m, and particularly preferably peel at a minimum tension to 100 N / m.

  In the present invention, the temperature at the peeling position on the metal support is preferably -50 to 40 ° C, more preferably 10 to 40 ° C, and most preferably 15 to 30 ° C.

5) Drying and stretching step After peeling, a drying device 35 that alternately conveys the web through a plurality of rolls arranged in the drying device and / or a tenter stretching device 34 that clips and conveys both ends of the web with a clip are used. And dry the web.

  Generally, the drying means blows hot air on both sides of the web, but there is also a means for heating by applying microwaves instead of the wind. Too rapid drying tends to impair the flatness of the finished film. Drying at a high temperature is preferably performed from about 8% by mass or less of the residual solvent. Throughout the drying is generally carried out at 40-250 ° C. It is particularly preferable to dry at 40 to 160 ° C.

  When using a tenter stretching apparatus, it is preferable to use an apparatus that can independently control the film gripping length (distance from the start of gripping to the end of gripping) left and right by the left and right gripping means of the tenter. In the tenter process, it is also preferable to intentionally create sections having different temperatures in order to improve planarity.

  It is also preferable to provide a neutral zone between different temperature zones so that the zones do not interfere with each other.

  In addition, extending | stretching operation may be divided | segmented and implemented in multiple steps, and it is also preferable to implement biaxial stretching in a casting direction and a width direction. When biaxial stretching is performed, simultaneous biaxial stretching may be performed or may be performed stepwise.

  In this case, stepwise means that, for example, stretching in different stretching directions can be sequentially performed, stretching in the same direction is divided into multiple stages, and stretching in different directions is added to any one of the stages. Is also possible. That is, for example, the following stretching steps are possible.

-Stretch in the casting direction-Stretch in the width direction-Stretch in the casting direction-Stretch in the casting direction-Stretch in the width direction-Stretch in the width direction-Stretch in the casting direction-Stretch in the casting direction Simultaneous biaxial stretching includes stretching in one direction and contracting the other while relaxing the tension. The preferable draw ratio of simultaneous biaxial stretching can be taken in the range of x1.01 to x1.5 times in both the width direction and the longitudinal direction.

  When the tenter is used, the residual solvent amount of the web is preferably 20 to 100% by mass at the start of the tenter, and it is preferable to perform drying while applying the tenter until the residual solvent amount of the web becomes 10% by mass or less. More preferably, it is 5% by mass or less.

  30-160 degreeC is preferable, as for the drying temperature in the case of performing a tenter, 50-150 degreeC is more preferable, and 70-140 degreeC is the most preferable.

  In the tenter process, it is preferable that the temperature distribution in the width direction of the atmosphere is small from the viewpoint of improving the uniformity of the film. The temperature distribution in the width direction in the tenter process is preferably within ± 5 ° C, and within ± 2 ° C. Is more preferable, and within ± 1 ° C. is most preferable.

6) Winding process This is a process in which the amount of residual solvent in the web becomes 2% by mass or less, and is taken up by the winder 37 as a film. Can be obtained. It is particularly preferable to wind up at 0.00 to 0.10% by mass.

  As a winding method, a generally used method may be used. There are a constant torque method, a constant tension method, a taper tension method, a program tension control method with a constant internal stress, and the like.

  The film according to the present invention is preferably a long film. Specifically, the film has a thickness of about 100 m to 5000 m and is usually provided in a roll shape. Moreover, it is preferable that the width | variety of a film is 1.3-4m, and it is more preferable that it is 1.4-2m.

  Although there is no restriction | limiting in particular in the film thickness of the film concerning this invention, It is preferable that it is 20-200 micrometers, It is more preferable that it is 25-150 micrometers, It is especially preferable that it is 30-120 micrometers.

<Method for producing resin support by melt casting film formation method>
A method for producing the resin support according to the present invention as a film-like resin support by a melt casting film forming method will be described.

<Melted pellet manufacturing process>
It is preferable that the composition constituting the film made of thermoplastic resin and microfibrillated cellulose used for melt extrusion is usually kneaded in advance and pelletized.

  Pelletization may be performed by a known method, for example, an additive consisting of a dried thermoplastic resin and microfibrillated cellulose is supplied to an extruder with a feeder and kneaded using a single or twin screw extruder, It can be produced by extruding from a die into a strand, cooling with water or air, and cutting.

  It is important to dry the raw material before extruding to prevent decomposition of the raw material. In particular, since the cellulose ester easily absorbs moisture, it is preferable to dry it at 70 to 140 ° C. for 3 hours or more with a dehumidifying hot air dryer or a vacuum dryer to keep the moisture content at 200 ppm or less, and further 100 ppm or less.

  Additives may be fed into the extruder and fed into the extruder, or may be fed by individual feeders. In order to mix a small amount of additives such as an antioxidant uniformly, it is preferable to mix them in advance.

  The antioxidant may be mixed with each other, and if necessary, the antioxidant may be dissolved in a solvent, impregnated with a thermoplastic resin and mixed, or mixed by spraying. May be.

  A vacuum nauter mixer or the like is preferable because drying and mixing can be performed simultaneously. Moreover, when touching with air, such as an exit from a feeder part or die | dye, it is preferable to set it as atmosphere, such as dehumidified air and dehumidified N2 gas.

  The extruder is preferably processed at as low a temperature as possible so that the shearing force is suppressed and the resin can be pelletized so as not to deteriorate (molecular weight reduction, coloring, gel formation, etc.). For example, in the case of a twin screw extruder, it is preferable to rotate in the same direction using a deep groove type screw. From the uniformity of kneading, the meshing type is preferable.

  A film is formed using the pellets obtained as described above. It is also possible to feed the raw material powder directly to the extruder with a feeder and form a film as it is without pelletization.

<Process for extruding molten mixture from die to cooling roll>
First, using a single-screw or twin-screw type extruder, the melt temperature Tm when extruding the pellet is about 200 to 300 ° C., filtered through a leaf disk type filter or the like to remove foreign matters, The film is coextruded into a film, solidified on a cooling roll, and cast while pressing with an elastic touch roll.

  When introducing from the supply hopper to the extruder, it is preferable to prevent oxidative decomposition or the like under vacuum or reduced pressure or in an inert gas atmosphere. Tm is the temperature of the die exit portion of the extruder.

  When foreign matter such as scratches or plasticizer aggregates adheres to the die, streak-like defects may occur. Such defects are also referred to as die lines, but in order to reduce surface defects such as die lines, it is preferable to have a structure in which the resin retention portion is minimized in the piping from the extruder to the die. . It is preferable to use a die that has as few scratches as possible inside the lip.

  The inner surface that contacts the molten resin such as an extruder or a die is preferably subjected to surface treatment that makes it difficult for the molten resin to adhere to the surface by reducing the surface roughness or using a material having a low surface energy. Specifically, a hard chrome plated or ceramic sprayed material is polished so that the surface roughness is 0.2 S or less.

  In the present invention, there is no particular limitation on the cooling roll, but it is a roll having a structure in which a heat medium or a refrigerant body whose temperature can be controlled flows through a high-rigidity metal roll, and its size is not limited. It is sufficient that the film is large enough to cool the film, and the diameter of the cooling roll is usually about 100 mm to 1 m.

  Examples of the surface material of the cooling roll include carbon steel, stainless steel, aluminum, and titanium. Further, in order to increase the hardness of the surface or improve the releasability from the resin, it is preferable to perform a surface treatment such as hard chrome plating, nickel plating, amorphous chrome plating, or ceramic spraying.

  The surface roughness of the chill roll surface is preferably 0.1 μm or less in terms of Ra, and more preferably 0.05 μm or less. The smoother the roll surface, the smoother the surface of the resulting film. Of course, it is preferable that the surface processed is further polished to have the above-described surface roughness.

  In the present invention, as an elastic touch roll, JP-A-03-124425, JP-A-08-224772, JP-A-07-1000096, JP-A-10-272676, WO97 / 028950, JP-A-11-235747, A thin-film metal sleeve-covered silicon rubber roll having a surface as described in JP-A No. 2002-36332, JP-A No. 2005-172940 and JP-A No. 2005-280217 can be used.

  When peeling the film from the cooling roll, it is preferable to control the tension to prevent deformation of the film.

<Extension process>
In the present invention, the film obtained as described above can be further stretched 1.01 to 3.0 times in at least one direction after passing through the step of contacting the cooling roll.

  Preferably, the film is stretched 1.1 to 2.0 times in both the longitudinal (film transport direction) and lateral (width direction) directions.

  As a method of stretching, a known roll stretching machine or tenter can be preferably used. In particular, when the optical film also serves as a polarizing plate protective film, it is preferable to stack the polarizing film in a roll form by setting the stretching direction to the width direction.

  By stretching in the width direction, the slow axis of the optical film becomes the width direction.

  Usually, the draw ratio is 1.1 to 3.0 times, preferably 1.2 to 1.5 times, and the draw temperature is usually Tg to Tg + 50 ° C. of the resin constituting the film, preferably Tg to Tg + 50 ° C. In the temperature range.

  The stretching is preferably performed under a uniform temperature distribution controlled in the longitudinal direction or the width direction. The temperature is preferably within ± 2 ° C, more preferably within ± 1 ° C, and particularly preferably within ± 0.5 ° C.

  When the film-like resin substrate produced by the above method is used as an optical film, the film may be contracted in the longitudinal direction or the width direction for the purpose of adjusting the retardation of the optical film and reducing the dimensional change rate.

  In order to shrink in the longitudinal direction, for example, there is a method of contracting the film by temporarily clipping out the width stretching and relaxing in the longitudinal direction, or by gradually narrowing the interval between adjacent clips of the transverse stretching machine.

  The uniformity in the slow axis direction is also important, and the angle is preferably −5 to + 5 ° with respect to the film width direction, more preferably in the range of −1 to + 1 °, and particularly −0. It is preferably in the range of 5 to + 0.5 °, particularly preferably in the range of −0.1 to + 0.1 °. These variations can be achieved by optimizing the stretching conditions.

  The film-like resin substrate of the present invention is preferably a long film. Specifically, the film-like resin substrate has a thickness of about 100 m to 5000 m and is usually provided in a roll shape. Moreover, it is preferable that the width | variety of a film is 1.3-4m, and it is more preferable that it is 1.4-2m.

  There is no restriction | limiting in particular in the film thickness of the film-form resin substrate which concerns on this invention, It is preferable to change according to the objective. For example, when using for a polarizing plate protective film, it is preferable that it is 20-200 micrometers, It is more preferable that it is 25-150 micrometers, It is especially preferable that it is 30-120 micrometers.

<Manufacturing device for support>
FIG. 1 is a schematic flow sheet showing an overall configuration of an example of a support manufacturing apparatus according to the present invention. In FIG. 1, the support is manufactured by mixing a film material such as a thermoplastic resin and then using the extruder 1 to melt and extrude from a casting die 4 onto a first cooling roll 5. The film 10 is further circumscribed by a total of three cooling rolls, that is, the second cooling roll 7 and the third cooling roll 8 in order, and is cooled and solidified. Next, the film 10 peeled off by the peeling roll 9 is then stretched in the width direction by holding both ends of the film by the stretching device 12 and then wound by the winding device 16. In addition, a touch roll 6 is provided that clamps the molten film on the surface of the first cooling roll 5 in order to correct the flatness. The touch roll 6 has an elastic surface and forms a nip with the first cooling roll 5.

  In the present invention, it is preferable to add a device for automatically cleaning the belt and the roll to the manufacturing apparatus. There are no particular restrictions on the cleaning device. For example, there are a method of niping a brush roll, a water absorbing roll, an adhesive roll, a wiping roll, an air blow method of blowing clean air, a laser incinerator, or a combination thereof. is there.

  In the case where the cleaning roll is nipped, the cleaning effect is great if the belt linear velocity and the roller linear velocity are changed.

(Preparation of cellulose nanofiber dispersion 1)
After dispersing 0.063 g of TEMPO and 0.63 g of sodium bromide in 375 ml of water in a fiber obtained by treating a sulfite bleached softwood pulp equivalent to 5 g in dry mass with a high-pressure homogenizer, 13 mass% sodium hypochlorite was dispersed in 375 ml of water. The reaction was started by adding hypochlorous acid to the aqueous solution so that the amount of sodium hypochlorite was 2.5 mmol per 1 g of pulp. During the reaction, a 0.5 M aqueous sodium hydroxide solution was added dropwise to keep the pH at 10.5. When no change in pH was observed, the reaction was considered to be completed, and the reaction product was filtered, then washed with sufficient water and filtered to obtain a reaction product fiber. This was washed with 300 ml of ethanol, and then the substitution with acetone was repeated to completely remove moisture and alcohol components in the medium.

  Next, 1.9 equivalents of acetic anhydride and 2.7 equivalents of acetic acid were added to a toluene solvent containing 5 g of the fiber prepared above and 25 ml of toluene in a 100 ml three-necked flask equipped with a magnetic stirrer, and stirred for 10 minutes. did.

Thereafter, 0.04 equivalent of 60% strength HClO ₄ was added and reacted with stirring for 5 min.

  After completion of the reaction, the product was obtained by filtration after washing with toluene / methanol. Further, the solid was added to a 200 ml beaker, dispersed in 20 ml of methanol and 10 ml of pure, neutralized with a 0.5N aqueous sodium hydroxide solution, and stored in ethanol.

  When the cellulose slurry was treated 5 times with an ultrahigh pressure homogenizer at a pressure of 140 MPa, a transparent gel dispersion was obtained.

(Preparation of support 1)
Subsequently, using the produced cellulose nanofiber dispersion 1, a cellulose nanofiber-containing support 1 having a film thickness of 100 μm and a winding number of 5000 m was produced using the following dope solution.

(Preparation of dope solution)
120 parts by mass of triacetyl cellulose 840 parts by mass of cellulose nanofiber dispersion 1 (20 parts by mass as solid content of cellulose nanofibers)
10 parts by mass of plasticizer (trimethylolpropane tribenzoate) <Preparation of supports 2 and 3>
Using the matrix material shown in Table 1, a cellulose nanofiber-containing support was produced in the same manner as described above.

<Preparation of Support 4>
After pulverizing powdered cellulose NP fiber W-10MG2 (average particle diameter 10 μm) of Nippon Paper Chemical Co., Ltd. with a high-pressure homogenizer until the average fiber diameter is 1 μm or less, it is applied to a grinder (“KM1-10” manufactured by Kurita Machinery Co., Ltd.). Then, the operation of passing the aqueous suspension through the disk rotating at 1200 rpm in a substantially contacted state from the center to the outside was performed 30 times (30 passes). An amount corresponding to 1 part by mass of Polydimethylsiloxane DMS-H03 from Geles was added to the obtained suspension, and the dispersion was subjected to dispersion treatment using a bead disperser using zirconia beads having an average particle diameter of 2 μm. The zirconia beads were removed by centrifugation and filtration and then dried to obtain cotton-like cellulose nanofibers: CNF-1. A part of the suspension before drying was taken out and water was evaporated, followed by observation with an electron microscope. The average fiber diameter was 150 nm and the average fiber length was 450 nm.

Next, in 37 parts by mass of a polyethylene resin, linear low density polyethylene [manufactured by Nippon Polychem Co., Ltd., trade name: FW20G, density: 0.921 g / cm ³ , MI: 1 g / 10 min] 32 parts by mass (polyethylene series) 5 parts by mass of branched low-density polyethylene (manufactured by Nippon Polychem Co., Ltd., trade name: LF441, density: 0.919 g / cm ³ , MI: 2 g / 10 min) with respect to 86% by mass in the resin, and the cellulose After 5 parts by mass of nanofibers were mixed with a tumbler mixer, they were uniformly kneaded at 220 ° C. using a tandem kneading extruder and processed into pellets. The pellets were melt-formed at 200 ° C. using an extruder equipped with a circular die to produce a cellulose nanofiber-containing support 4.

<Coating of polysilazane layer>
The substrates 1 to 4 prepared above were bar-coated with a 3% perhydropolysilazane solution in dibutyl ether (NL120, manufactured by Clariant) so that the thickness of the dried film was 100 nm, and then naturally left for 3 minutes. After drying, samples 1 to 4 were fabricated by annealing in an oven at 90 ° C. for 30 minutes and providing a polysilazane layer (gas barrier layer).

Comparative Example 1
In accordance with the examples described in JP-A-2008-242154, a culture solution was added to a strain of acetic acid bacteria stored in a freeze-dried state, followed by static culture for 1 week (25-30 ° C.). Among the bacterial celluloses produced on the surface of the culture solution, those having a relatively large thickness were selected, and a small amount of the culture solution of the strain was taken and added to a new culture solution. And this culture solution was put into the large incubator, and static culture was performed at 25-30 degreeC for 7-30 days. In the culture solution, glucose 2% by mass, Bacto yeast extra 0.5% by mass, Bacto peptone 0.5% by mass, Disodium hydrogen phosphate 0.27% by mass, Citric acid 0.115% by mass, Magnesium sulfate hemihydrate An aqueous solution (SH culture solution) adjusted to pH 5.0 with hydrochloric acid was used, which was 0.1% by mass of the Japanese product.

  The bacterial cellulose produced in this manner is taken out from the culture solution and boiled in a 2% by weight aqueous alkali solution for 2 hours. Then, the bacterial cellulose is taken out from the alkaline treatment solution, sufficiently washed with water, and the alkaline treatment solution is removed. Bacteria in bacterial cellulose were dissolved and removed. Subsequently, the obtained water-containing bacterial cellulose (bacterial cellulose having a water content of 95 to 99% by mass) was hot-pressed at 120 ° C. and 2 MPa for 3 minutes to obtain a bacterial cellulose (BC) sheet having a thickness of about 50 μm (water content of 0% by mass). %).

  The obtained bacterial cellulose sheet is a product name E3410 (hereinafter referred to as this uncured epoxy resin) manufactured by NTT Advanced Technology, which is an uncured ultraviolet curable epoxy resin (Young's modulus after curing is 0.01 GPa). And dipped in “uncured epoxy resin A” for 12 hours. At that time, the obtained composite material sheet had a thickness of 60 μm and contained 56% by mass of the bacterial cellulose sheet.

Next, a 30 μm-thick thin glass sheet was bonded to the taken out sheet, and then irradiated with ultraviolet rays (total irradiation energy amount: 11 J / cm ² ) to cure the resin. Thereafter, under atmospheric pressure and air atmosphere, 60 By annealing at 30 ° C. for 30 minutes, a flexible substrate having a thin glass sheet and a composite material sheet was obtained. This was used as a sample of Comparative Example 1.

Comparative Example 2
In accordance with the examples described in Japanese Patent Application Laid-Open No. 2009-194039, for example, Me ₂ SiO ₂ having a Tg of about 100 ° C. under reduced pressure of about 0.1 to 100 kPa on the BC sheet. The low melting point glass 2 made of —SnO—P ₂ O ₅ based glass was used to be immersed in the liquid low melting point glass 2 for about 8 to 15 hours. This was used as the sample of Comparative Example 2.

Comparative Example 3
In the production of the support 1, a support was produced in the same manner except that the cellulose nanofiber was not included, and a polysilazane layer was applied to the support as described above to produce a sample of Comparative Example 3. did.

<Evaluation>
The following evaluation was performed about the sample obtained above.

(Adhesion)
A cross-cut tape peeling test was conducted in accordance with JIS K 5600-5-6.

  Using a cutter, put 11 scratches of 1 mm in length and width on the surface of the sample to make 100 squares of 1 mm square (cross cut), and press the tape using cello tape (registered trademark) manufactured by Nichiban Co., Ltd. Then, peeling was repeated three times at the same place. Then, the sample surface after tape peeling was observed visually, and the following references | standards evaluated.

Evaluation criteria for adhesion ○: Affected part is 5% or less △: Affected part exceeds 5%, but 30% or less ×: Affected part exceeds 30%

(Flexibility (flexibility))
Evaluation of flexibility (flexibility) was performed by a method based on the MIT test described in JIS P 8115: 2001, and whether or not cracks occurred in a bending test at 90 ° C. was visually confirmed and evaluated based on the following criteria. .

○: No crack is generated in a bending test of 100 times or more. ×: A crack is generated in a bending test of less than 100 times.

(durability)
The sample was stored for 700 hours in a high-temperature and high-humidity thermo with a temperature of 80 ° C. and a humidity of 90% RH to prepare a wet heat treatment sample. Next, the moisture-heat treated film was conditioned for 24 hours under the conditions of a temperature of 23 ° C. and a relative humidity of 55%, and then gas barrier properties were evaluated.

  The gas barrier property was evaluated by evaluating water vapor permeability by a Ca corrosion method. Specifically, water vapor permeability was evaluated by holding a gas barrier sheet under conditions of 40 ° C. and 100% RH and observing corrosion growth of Ca.

○: Gas barrier property as a flexible substrate is high and practical Δ: Gas barrier property as a flexible substrate is slightly lacking ×: Gas barrier property as a flexible substrate is not present Table 1 shows the results of the above evaluation.

  As is apparent from the results shown in Table 1, it can be seen that the sample according to the present invention is superior in adhesion, flexibility (flexibility), and durability to the sample of the comparative example.

DESCRIPTION OF SYMBOLS 1 Extruder 2 Filter 3 Static mixer 4 Casting die 5 Rotating support body (1st cooling roll)
6 Nipping pressure rotating body (touch roll)
7 Rotating support (second cooling roll)
8 Rotating support (3rd cooling roll)
9 Peeling roll 10 Film 11, 13, 14 Transport roll 12 Stretching machine 15 Slitter 16 Winding machine F Resin film

Claims (4)

  A resin film substrate having a gas barrier layer provided on a support, the support containing a thermoplastic resin and microfibrillated cellulose, and the gas barrier layer containing an inorganic oxide formed from a ceramic precursor A resin film substrate.   The resin film substrate according to claim 1, wherein the thermoplastic resin is a resin selected from a cellulose ester resin, a polycarbonate resin, an acrylic resin, and a polyolefin resin.   The resin ceramic substrate according to claim 1, wherein the ceramic precursor contains polysilazane.   It is a manufacturing method of the resin film board | substrate which manufactures the resin film board | substrate as described in any one of Claim 1- Claim 3, Comprising: At least (1) The ceramic precursor which forms an inorganic oxide film by heating A method for producing a resin film substrate, comprising: a step of coating; and (2) a step of locally heating a coating film of the ceramic precursor to form an inorganic oxide.

Images