CN103229080A

CN103229080A - Mold release film

Info

Publication number: CN103229080A
Application number: CN2011800577013A
Authority: CN
Inventors: 斋藤智久; 有马奈美
Original assignee: Mitsubishi Plastics Inc
Current assignee: Mitsubishi Chemical Corp; Mitsubishi Rayon Co Ltd
Priority date: 2010-12-27
Filing date: 2011-12-19
Publication date: 2013-07-31
Anticipated expiration: 2031-12-19
Also published as: KR101707863B1; CN103229080B; KR20140001885A

Abstract

Provided is an inexpensive mold release film, whereby the peel rate dependency is minized when a base-less double-sided adhesive sheet is used for optical purposes, for example in a touch panel, a liquid crystal polarizing plate and a retardation plate, to improve the productivity, cost performance or the like of the mold release film, and to impart a property of preventing the formation of any oligomer or a property of testing on the formation of any oligomer to the mold release film to thereby reduce the occurrence of contamination during a process or the formation of foreign substances in an adhesive agent. A mold release film comprising a polyester film having a mold release layer, wherein the mold release layer is bonded to an adhesive layer in a base-less double-sided adhesive sheet upon use, the mold release layer is a silicone-type mold release layer comprising (a) a silicone resin having an alkenyl group as a functional group, (b) a silicone resin having an alkyl group as a functional group, (c) a component capable of migrating into the adhesive layer, and (d) a platinum-containing catalyst, the content of the component (c) capable of migrating is 5-20 wt%, the low-speed peel force of the mold release layer at a speed of 300 mm/min falls within the range of 10-20 mN/cm, and the high-speed peel force of the mold release layer at a speed of 10000 mm/min is up to 2.5 times greater than the low-speed peel force.

Description

Mold release film

Technical field

The present invention relates to mold release film, specifically relate to and be fit to the mold release film in the no base material two sides adhesive sheet purposes of optical applications, used.

Background technology

In the prior art, the known various adhesive sheets that face between the object is bonding, a kind of as adhesive sheet, known no base material two sides adhesive sheet.No base material two sides adhesive sheet is by constituting at the relative more weak relative stronger heavy stripping film with peeling force of light stripping film of the stacked peeling force in the two sides of bond layer, after the stripping film on two sides is removed, for not supporting the two sides adhesive sheet that bond layer is only arranged of base material.No base material two sides adhesive sheet, at first light stripping film is stripped from, and the one side of the bond layer that exposes is bonded on the body surface, after this is bonding, further peel off heavy stripping film, the another side of the bond layer that exposes is bonded on the different body surfaces, thus, quilt cover is bonding between the object.

In recent years, the purposes of no base material two sides adhesive sheet enlarges day by day, also can use in the parts of various optical applications etc.For example,, will not have the light mold release film of peeling force of base material two surface adhesive sheets sometimes and peel off, on this face, paste Polarizer, use the heavy mold release film of peeling force in its opposing face one side as the parts of LCD.

From the operability of producing, consideration is in the processing of to a certain degree high-speed range, but in the mold release film of gently peeling off, certainly reach light peeling force, but reach this light peeling force, to improve process velocity, also can not dwindle difference with the peeling force of the mold release film of heavily peeling off as far as possible be unusual (patent documentation 1) of difficulty even reach simultaneously.If dwindle with the difference of the peeling force of the mold release film of heavily peeling off, in stripping process, the problem that the film that the two sides can occur is peeled off simultaneously and reduced to cause that bonding agent also is stripped from together etc. owing to the peeling force difference is causing bad (patent documentation 2) aspect processability, the throughput rate.

The control of above-mentioned peeling force difference is difficulty very, must carry out the various selections and the control (patent documentation 1 and 2) of silicone ingredients, and, can think that the hardness control of silicone coated film also is necessary.

In addition, in the adhesive sheet of no base material two sides, in the purposes in the outside that is used to little flat board of touch panel or controller homalographic etc., when making goods, near people's eyes, in case the bright spot of foreign matter etc. is outstanding, will visually produce bad, so need sometimes strengthen to check.At this moment, under the state that is pasted with mold release film on the adhesive sheet of no base material two sides, check sometimes.In this case,, need the few foreign of film certainly, to the optical axis of film, be that the orientation of molecule manages also be necessary (patent documentation 3) in order to check easily.

And,, have because the foreign matter that polyester film low molecular composition that cause, that be called oligomer causes as one of above-mentioned foreign matter.If can prevent this oligomer, the foreign matter in the time of just can suppressing above-mentioned production is bad, and can prevent that film and operation before this from polluting.Wherein, in the present invention, so-called oligomer (OL) is defined as: after thermal treatment, carry out the cyclic trimer of crystallization in the low-molecular-weight thing that separate out on the film surface.

Technical literature formerly

Patent documentation

Patent documentation 1: TOHKEMY 2009-220496 communique

Patent documentation 2: Japanese kokai publication hei 10-158519 communique

Patent documentation 3: TOHKEMY 2003-231214 communique

Summary of the invention

Invent problem to be solved

The present invention In view of the foregoing finishes, the problem of its solution is to provide a kind of mold release film of cheapness, when will not have base material two sides adhesive sheet and be applied in optical applications, for example touch panel, liquid crystal Polarizer, the polarizer etc., the peeling rate dependence can be suppressed at Min., solve the problem of throughput rate, cost etc., and prevent oligomer, give inspectability, thereby reduce the foreign matter on operation pollution and the bonding agent.

Be used to solve the means of problem

In view of above-mentioned actual conditions, the present inventor furthers investigate, and found that: utilize the polyester film of the release layer with ad hoc structure, can easily solve above-mentioned problem, thereby finish the present invention.

Promptly, main points of the present invention are a kind of mold release film, it comprises the polyester film that possesses release layer, release layer is sticked on the adhesive linkage of no base material two sides adhesive sheet and use, release layer is the silicon-type release layer, release layer contains: have the organic siliconresin (a) of thiazolinyl as functional group, organic siliconresin (b) with alkyl, transfer composition (c) and platinum group catalyst (d) to the adhesive linkage transfer, the content that translates into branch (c) in the above-mentioned release layer is 5～20 weight %, the low speed peeling force of release layer when 300mm/ minute speed is the scope of 10～20mN/cm, and the high speed peeling force when 10000mm/ minute speed is below 2.5 times of low speed peeling force.

And, in the layer structure of optimal way of the present invention, between polyester film and silicon-type release layer, have coating and contain the coating fluid of polyvinyl alcohol (PVA) and the coating layer that obtains.

The invention effect

According to the present invention, can provide and gently peel off and mold release film that the peeling rate dependence is little, so its commercial value height.

Embodiment

＜polyester film＞

Polyester film as the mold release film base material of the present invention is will stretch according to the sheet that so-called extrusion molding melt extrudes from extrusion die and the film that obtains.

The polyester that constitutes above-mentioned film refers to by dicarboxylic acid and glycol or the polymkeric substance that contains ester group that obtained by polycondensation by hydroxycarboxylic acid.

As dicarboxylic acid, can the illustration terephthalic acid (TPA), m-phthalic acid, hexane diacid, azelaic acid, decanedioic acid, 2,6-naphthalenedicarboxylic acid, 1,4 cyclohexanedicarboxylic acid etc.As glycol, can illustration ethylene glycol, 1,4-butylene glycol, diethylene glycol, triethylene glycol, season pentanediol, 1,4 cyclohexane dimethanol, polyglycol etc.As hydroxycarboxylic acid, can the illustration P-hydroxybenzoic acid, 6-hydroxyl-2-naphthoic acid etc.As the typical example of such polymkeric substance, can the illustration polyethylene terephthalate or poly--2,6-(ethylene naphthalate) etc.

To give sliding and to prevent that producing scar in each operation is fundamental purpose, preferably cooperates particle in film.The kind of the particle that cooperates is so long as can give the particle of sliding and just be not particularly limited, as concrete example, for example can enumerate the particle of silicon dioxide, lime carbonate, magnesium carbonate, barium carbonate, calcium sulphate, calcium phosphate, magnesium phosphate, porcelain earth, aluminium oxide, titanium dioxide etc.In addition, also can use the thermotolerance organic granular of record in Japanese Patent Publication 59-5216 communique, the Japanese kokai publication sho 59-217755 communique etc.As other the example of thermotolerance organic granular, can enumerate thermosetting urea resin, thermosetting phenolic resin, thermosetting epoxy resin, benzoguanamine resin etc.In addition, also can use the part precipitation, the differential that in polyester manufacturing process, make metallic compounds such as catalyzer to loose and obtain separate out particle.

On the other hand, coating of particles also is not particularly limited, and can use arbitrary shapes such as spherical, block, bar-shaped, flat.In addition, its hardness, proportion, color etc. also are not particularly limited.These a series of particles can be as required also with more than 2 kinds.

In addition, the mean grain size of particle is generally 0.01～3 μ m, is preferably the scope of 0.1～2 μ m.During less than 0.01 μ m, the situation of sliding can not be fully given in existence in mean grain size.On the other hand, when surpassing 3 μ m, when the system film of film, may be because this agglomeration of particles thing cause transparency decline, in addition, cause easily and break etc., aspect throughput rate, go wrong.

In addition, the content of particle is generally 0.001～5 weight %, is preferably the scope of 0.005～3 weight %.During less than 0.001 weight %, there is the inadequate situation of sliding of film at granule content, on the other hand,, has the transparent inadequate situation of film when adding when surpassing 5 weight %.

Method as cooperate particle in film is not particularly limited, and can adopt existing known method.For example, can add, but preferably finish the back interpolation in esterification or ester exchange reaction in the stage arbitrarily of making polyester.

Can also by use have the mixing extruder of ventilating opening will be in ethylene glycol or water etc. the slurry of dispersed particles and polyester raw material blending method or use mixing extruder to carry out through the method for dried granules and polyester raw material blending etc.

In addition, in film, except adding above-mentioned particle, can also add existing known antioxidant, antistatic agent, thermal stabilizer, lubricant, dyestuff, pigment etc. as required.

The thickness of polyester film is so long as just be not particularly limited in the scope that can make film, is generally 10～350 μ m, is preferably 38～125 μ m, the scope of 50～100 μ m more preferably.When the thickness of film is thinner than 10 μ m, can enumerate following problems: in this purposes, the bonding agent sheet is added the foreign that produces man-hour in operation etc. and be transferred on the bonding agent and and add coating official post in man-hour throughput rate variation etc. in mold release film.When the thickness of film was thick, the problem that cost rises appearred.

Then, specify the Production Example of polyester film of the present invention, but be not subjected to any qualification of following Production Example.That is, said polyester raw material before preferred the use will obtain the not method of drawing sheet with the chill roll cooling curing from the molten sheet that die head is extruded.At this moment,, preferably improve sheet and the adaptation of rotating drum cooler, preferably adopt static to apply driving fit method and/or liquid coating driving fit method in order to improve the planarity of sheet.Then, resulting not drawing sheet is stretched at biaxially oriented.At this moment, at first, utilize the drawing machine of roller or tentering mode that above-mentioned not drawing sheet is stretched in one direction.Draft temperature is generally 90～140 ℃, is preferably 95～120 ℃, and stretching ratio is generally 2.5～7 times, is preferably 3.0～6 times.Then, with the direction of the draw direction quadrature of phase one on stretch, at this moment, draft temperature is generally 90～170 ℃, stretching ratio is generally 3.0～7 times, is preferably 3.5～6 times.And, then with 180～270 ℃ temperature straining at down or 30% heat-treating under lax with interior, obtain Biaxially oriented film.In above-mentioned stretching, also can adopt to carry out the method for the stretching of a direction more than 2 stages.At this moment, the mode that preferably reaches above-mentioned scope respectively with the stretching ratio of final two directions is carried out.

In addition, about the polyester film manufacturing, also can adopt biaxial stretch-formed method simultaneously.Simultaneously biaxial stretch-formed method be with above-mentioned not drawing sheet usually with 90～140 ℃, preferably stretch simultaneously at operating direction and Width with 80～110 ℃ temperature controlled state and make the method for its orientation, as stretching ratio, count 4～50 times with the area multiplying power, be preferably 7～35 times, more preferably 10～25 times.Then, then with 170～250 ℃ temperature straining at down or 30% heat-treating under lax with interior, obtain the stretch orientation film.Biaxial stretch-formed device when adopting above-mentioned stretching mode can adopt spiral way, scalable manner, linear drives mode etc. to have known stretching mode now.

＜coating contains the coating fluid of polyvinyl alcohol (PVA) and the coating layer that obtains＞

The purpose that above-mentioned coating layer is set can also prevent to prevent the pollution when bond layer is pasted because the operation that OL causes is polluted except the OL sealing purpose.

The content of the polyvinyl alcohol (PVA) in coating layer is generally 10～100 weight %, is preferably 20～90 weight %, 30～90 weight % more preferably.When the content of polyvinyl alcohol (PVA) during less than 10 weight %, the oligomer sealing effectiveness is insufficient and undesirable.

Polyvinyl alcohol (PVA) can be synthetic by common polyreaction, is preferably water-soluble.The degree of polymerization of polyvinyl alcohol (PVA) is not particularly limited, and is generally more than 100, is preferably 300～40000.In the degree of polymerization is 100 when following, has the water tolerance downward trend of coating layer.The saponification degree of polyvinyl alcohol (PVA) is not particularly limited, and is generally 70 moles more than the %, be preferably 80 moles of % above, 99.9 moles below the %.

As required, can be in coating layer and with the adhesive resin of above-mentioned polyvinyl alcohol (PVA) water-soluble or water dispersible in addition.So-called adhesive resin be defined as with macromolecular compound safety evaluatio flow process outline (clear and in November, 60, chemical substance review conference edit) be benchmark, the number-average molecular weight (Mn) that recorded by gel permeation chromatography (GPC) is macromolecular compound more than 1000 and the material with film forming.As such adhesive resin, for example can enumerate polyester, polyurethane, acryl resin, vinylite, epoxy resin, amide resin, acrylate resin etc.These resins skeleton structure separately can be by copolymerization etc. and is had composite structure in fact.As adhesive resin, for example can enumerate acryl resin grafted polyester, acryl resin grafted polyurethane, vinylite grafted polyester, vinylite grafted polyurethane, acrylate resin grafting polyglycol etc. with composite structure.The use level of adhesive ingredients in the weight portion with respect to coating layer, is preferably following, the following scope of 30 weight portions more preferably of 50 weight portions.

As required, can also contain the cross-linking reaction compound in the coating layer.As the cross-linking reaction compound, can be selected from the urea system, melamine system, guanamine system, acrylamide of methylolation or alkanolization, polyamide-based etc. compound, polyamine class, epoxy compound, oxazoline compound, aziridine cpd, blocked isocyanate compounds, silane coupling agent, titanium coupling agent, zircoaluminate is the multifunctional low molecular compound and the macromolecular compound of coupling agent, metallo-chelate, organic acid anhydride, organic peroxide, heat or photoreactive vinyl compound and ultraviolet curable resin etc.

The cross-linking reaction compound, by with coating layer in the functional group that resin had contained cross-linking reaction takes place, can improve compendency, skin hardness, mar resistance, solvent resistance, the water tolerance of coating layer.For example, when easily the functional group of adhering resin is hydroxyl, as the cross-linking reaction compound, preferred melamine based compound, blocked isocyanate compounds, organic acid anhydride etc.; When the functional group of easy bonding polyester is organic acid and acid anhydrides thereof, as the cross-linking reaction compound, preferred epoxy based compound, melamine based compound, oxazoline based compound, metallo-chelate etc.; When easily the functional group of adhering resin is amine, as the cross-linking reaction compound, preferred epoxy based compound etc., preferably select for use with easy adhering resin in the high compound of cross-linking reaction efficient of contained functional group.As melamine compound, can illustration as the methoxy melamine of the melamine based compound of alkanol or alkyloxyalkanolization, butoxymethyl melamine etc., the product that also can use urea etc. to obtain with a part of cocondensation of melamine.

The cross-linking reaction compound needs only the reactive functional groups that must comprise more than the 2 officials energy in 1 molecule, both can be low molecular weight compound, also can be the high molecular polymer with reactive functional groups.The use level of cross-linking reaction compound, in weight portion with respect to coating layer, be preferably 50 weight portions following, more preferably 30 weight portions following, be preferably below 15 weight portions especially.

When adhesive resin is cooperated with arbitrary proportion with crosslinking chemical, because coating layer forms the restraining barrier densely, so can more effectively suppress OL.Therefore, can obtain to make as much as possible from the OL of polyester film non-cohesive on bonding agent and before manufacturing procedure in the effect that also can not overflow.

In order to improve the sliding of coating layer, as required, in coating layer, can contain nonactive particle.As nonactive particle, inorganic nonactive particle, organic nonactive particle are arranged.As inorganic nonactive particle, for example can enumerate silica dioxide gel, alumina gel, lime carbonate, titanium dioxide etc.As organic nonactive particle, for example can enumerate with following particle is the organic granular of representative: comprise polystyrene resin, polyacrylic resin, the homopolymer of tygon base system resin or the particulate of multipolymer, perhaps with them and the compound cross-linked particles that obtains of crosslinked composition.That the softening temperature of these nonactive particles or decomposition temperature are preferably is about more than 200 ℃, more preferably more than 250 ℃, be preferably more than 300 ℃ especially.When the average film thickness of coating layer is made as (L), select the mean grain size (d) of nonactive particle to make it satisfy the relation of 1/3≤d/L≤3, more preferably satisfy the relation of 1/2≤d/L≤2.

As required, coating layer can contain the adjuvant of a spot of surfactant, defoamer, coating improver, tackifier, low molecule antistatic agent, organic series lubricant agent, antioxidant, ultraviolet light absorber, gas-development agent, dyestuff, pigment etc.These adjuvants can use separately, also can be as required also with more than 2 kinds.Coating layer both can also can form on the two sides only in the single face formation of polyester film.Only when single face forms, can be as required, form the coating layer of other kinds at its opposing face, further give other characteristic.In addition, in order to improve coating and the cementability of coating fluid on film, can implement chemical treatment or discharge process etc. to the film before being coated with.

Forming the employed coating fluid of coating layer, from the viewpoint of security and wholesomeness, is that main medium is modulated with water preferably usually.As long as is main medium, can contain a spot of organic solvent to improve being separated into purpose or being purpose in water to improve filming performance with water.Organic solvent mixes when using with the water of the main medium of conduct, preferably use with the scope of in water, dissolving, if but be the long-time also unseparated such stable emulsion (emulsion, emulsion fluid) of placing, also can use with undissolved state in water.Organic solvent can use separately, also can be as required also with more than 2 kinds.

As method, can use counter-rotating roller coat, gravure coating, rod of record in " the コーティ Application グ mode " of former rugged brave work, the distribution in 1979 of Omaki bookstore to be coated with, air knife coating etc. at the surface coated coating fluid of polyester film.

The method that coating layer is set is not particularly limited, and can suitably adopt the method (online coating) of coating coating fluid in the operation of making polyester film.Particularly, can be set forth in drawing sheet surface coated coating fluid not and carry out dry method, at monadic stretching membrane surface coated coating fluid and carry out dry method, at biaxially-stretched film surface coated coating fluid and carry out dry method etc.Wherein, behind unstretching film or monadic stretching membrane surface coated coating fluid, in the process that film is heat-treated, be economical with the method for coating layer dry solidification simultaneously.In addition, as the method that forms coating layer, as required, also can adopt and with several method of above-mentioned coating process.Particularly, can be set forth in not the 1st layer of drawing sheet surface coated and carry out drying, afterwards, after the single shaft direction stretches, be coated with the 2nd layer and carry out dry method etc.

When by online coating coating layer being set, above-mentioned a series of compounds are made aqueous solution or aqueous dispersion, the main points of preferably making the lamination resin molding are adjusted to solid component concentration for coating on polyester film the coating fluid of 0.1～50 weight % left and right sides standard.In addition, in the scope of not damaging main points of the present invention, be purpose to improve dispersiveness in water, to improve film forming etc., can contain a spot of organic solvent in the coating fluid.Organic solvent can only have a kind, also can suitably use more than 2 kinds.

Drying and condition of cure when forming coating layer on polyester film are not particularly limited, and for example, when by online coating coating layer being set, can be that standard is heat-treated with 70～280 ℃, 3～200 seconds usually.In addition, as required, can and use the active energy beam irradiation of thermal treatment and ultraviolet ray irradiation etc.Can also implement the surface treatment of corona treatment, Cement Composite Treated by Plasma etc. in advance to polyester film.

When mold release film has the coating layer that contains polyvinyl alcohol (PVA), after mold release film being heat-treated (180 ℃, 10 minutes), utilize dimethyl formamide to be preferably 1.0mg/m from the OL amount that painting layer surface extracts ²Below.At OL greater than 1.0g/m ²The time, exist operation to pollute, when bonding bonding agent, decrease in yield etc. bad of foreign matter, goods appears producing sometimes.

The thickness of coating layer is generally 0.002～1.0g/m ², be preferably 0.005～0.5g/m ², 0.01～0.2g/m more preferably ²Scope.At thickness less than 0.002g/m ²The time, possibly can't obtain sufficient adaptation.Greater than 1.0g/m ²The time, may cause the adhesive of the outward appearance and the transparency, film to worsen.The analysis of composition for example can be undertaken by the surface analysis of TOF-SIMS etc. in the coating layer.

In addition, in the present invention, can be for the single side surface at least of the layer that constitutes at polyester, with the poor polyester coextrusion of OL and stacked structure by common OL content.When having such structure, in mold release film of the present invention, can obtain to prevent because the OL that separates out produces the effect of bright spot, thus preferred especially.

＜release layer＞

Release layer among the present invention be contain have thiazolinyl as the organic siliconresin (a) of functional group, have the transfer composition (c) that alkyl shifts as the organic siliconresin (b) of functional group, to adhesive linkage and a silicon-type release layer of platinum group catalyst (d).

At first, the curing type silicone resin that contains thiazolinyl, as polydiorganosiloxanepolyurea, can enumerate dimethyl siloxane methyl hexenyl silicone copolymers (96 moles of % of dimethyl siloxane units of strand two terminal trimethylsiloxy end-blockings, 4 moles of % of methyl hexenyl siloxane unit), dimethyl siloxane methyl hexenyl silicone copolymers (97 moles of % of dimethyl siloxane units of strand two terminal dimethylvinylsiloxy end-blockings, 3 moles of % of methyl hexenyl siloxane unit), dimethyl siloxane methyl hexenyl silicone copolymers (95 moles of % of dimethyl siloxane units of strand two terminal dimethyl hexenyl siloxy end-blockings, 5 moles of % of methyl hexenyl siloxane unit).

Then, the curing type silicone resin that contains alkyl, as organic hydrogen containing siloxane, can enumerate the methyl hydrogen containing siloxane of strand two terminal trimethylsiloxy end-blockings, the dimethyl siloxane methyl hydrogen-containing siloxane multipolymer of strand two terminal trimethylsiloxy end-blockings, the methyl hydrogen containing siloxane of the hydrogeneous siloxy end-blocking of strand two terminal dimethyl, the dimethyl siloxane methyl hydrogen-containing siloxane multipolymer of the hydrogeneous siloxy end-blocking of strand two terminal dimethyl.

Mold release film of the present invention can stick on release layer on the adhesive linkage of no base material two sides adhesive sheet and use, and above-mentioned organic siliconresin contains the transfer composition that oriented adhesive linkage shifts.As shifting composition, typically use silicone oil.Silicone oil is straight silicone oil (straight silicone oil), is called the silicone oil of modified silicon oil, can enumerate following material.As straight silicone oil, can enumerate dimethyl silicon oil, methyl phenyl silicone oil, Methyl Hydrogen Polysiloxane Fluid etc.In addition, as modified silicon oil, can enumerate side chain type polyether-modified, aralkyl modification, fluoro-alkyl modification, long chain alkyl modified, higher fatty acid is ester modified, polyether-modified, the polyethers methoxyl modification of higher fatty acid amides modification, the long chain alkyl modified aralkyl modification of polyethers, phenyl modified, two tip type etc.Straight silicone oil, modified silicon oil are non-reacted no official can oil.

The content that shifts composition is 5～20 weight %, be preferably 10～13 weight %, 0.1～5.0 weight % more preferably.When the content that shifts composition was lower than 5 weight %, speed dependence described later increased, during greater than 20 weight %, and the unfavorable condition that exist curable significantly to descend, adaptation also worsens.

As the object lesson of resin-coated dose of the silicon-type that can use in the present invention, can enumerate KS-774, KS-775, KS-778, KS-779H, KS-847H, KS-856, X-62-2422, X-62-2461 that Shin-Etsu Chemial Co., Ltd produces; DKQ3-202, DKQ3-203, DKQ3-204, DKQ3-205, DKQ3-210 that DOW CORNING ASIA company produces; YSR-3022, TPR-6700, TPR-6720, TPR-6721 that Toshiba Silicones company produces; LTC300B, the LTC303E that Dow Corning Toray company produces, LTC310, LTC314, SRX357, BY24-749, SD7333, BY24-179, SP7015, SP7259, SD7220, SD7226, SD7229 etc.For fissility of adjusting release layer etc., can also further and use release control agent.

Above-mentioned silicon-type comprises for resin-coated dose: have thiazolinyl as the organic siliconresin (a) of functional group, have alkyl as the organic siliconresin (b) of functional group, to the transfer composition (c) that adhesive linkage shifts, have thiazolinyl as the organic siliconresin (a) of functional group with have the ratio (b)/(a) of alkyl and be generally 0.5～2 weight ratio as the organic siliconresin (b) of functional group.In addition, also can use among the present invention and have thiazolinyl and alkyl organic siliconresin as functional group.

As the method that release layer is set on polyester film, same with the situation of above-mentioned coating layer, can use existing known coating process.Coating weight when forming release layer is generally 0.01～1g/m ²Scope.

At the face that release layer is not set adhesive linkage, antistatic backing can be set, prevent oligomer separate out the layer etc. coating layer, in addition, also can implement the surface treatment of corona treatment, Cement Composite Treated by Plasma etc. to polyester film.

In the present invention, clean and firm in order to make release layer, use the platinum group catalyst that promotes the add-on type reaction.As this composition, can the illustration chloroplatinic acid, the platinum series compound of the coordination compound of coordination compound, chloroplatinic acid and the alkenyl siloxane of alcoholic solution, chloroplatinic acid and the alkene of chloroplatinic acid etc., platinum black, be carried with platinum silicon dioxide, be carried with the acticarbon of platinum.The content of platinum group catalyst is generally 0.3～3.0 weight %, is preferably the scope of 0.5～2.0 weight % in the release layer.When the content of the platinum group catalyst in the release layer is lower than 0.3 weight %, because peeling force is bad and the curing reaction in coating layer is insufficient, so may produce unfavorable conditions such as planar deterioration.On the other hand, when the content of the platinum group catalyst in the release layer during, may cause cost to increase and reactive high, operation condition of poor that gel foreign matter etc. occurs greater than 3.0 weight %.

In addition, because the reactivity of add-on type reaction is very high, so, according to circumstances, add alkynol sometimes as reaction suppressor.Its composition is the organic compound with carbon-to-carbon triple bond and hydroxyl, is preferably to be selected from 3-methyl isophthalic acid-butine-3-alcohol, 3 compound in the pure and mild phenyl butynol of 5-dimethyl-1-hexin-3-.

＜peeling force＞

In the present invention, so-called peeling force is meant the value that records by following mensuration, paste two sides jointing tape (day eastern electrician's production, " No.31B ") in demoulding aspect, after room temperature is placed 1 hour, with the peel angle with base material film be 180 °, when draw speed is with tape stripping arbitrarily, the value that records by cupping machine.

In the present invention, the method of adjusting peeling force can realize by selecting the composition in the release layer, but also can adopt other means, the preferred variety of release agents that mainly changes the organosilicon release layer according to desirable peeling force, and, because peeling force depends on the coating weight of the release agent of use to a great extent, so, the method for the coating weight of this release agent more preferably adjusted.

In the present invention, utilize the residual bonding rate of the No.31B adhesive tape of Nitto Denko Corp's production to be generally 65%～90%, to be preferably 70%～85%.When residual bonding rate was lower than 65%, the metastatic height caused bonding agent to add the man-hour roller and pollutes and transfer to adhesive side, degradation under the bonding peeling force occurs.In addition, when residual bonding rate is 90% when above, can not suppress speed dependence little.

The peeling force value of mold release film of the present invention, the low speed peeling force when 300mm/ minute speed is the scope of 10～20mN/cm.During less than 10mN/cm, peeling force kicks the beam in this peeling force, also occurs the unfavorable condition of peeling off easily under the situation that does not need to peel off originally.In peeling force during greater than 20mN/cm, reduce with the peeling force difference of the heavy mold release film of peeling force, exist and occur the problem that selected the scope bad or mold release film that peeling force is heavy narrows down etc. in the stripping process.

High speed peeling force during the 10000mm/ when further considering processability minute speed is below 2.5 times of above-mentioned low speed peeling force.At the ratio of this peeling force during greater than 2.5 times, reduce with the peeling force difference of the heavy mold release film of peeling force, be difficult in stripping process, properly peel off or bonding agent is peeled off together.

The Martens hardness of the release layer of mold release film of the present invention is generally 400N/mm ²More than, be preferably 450N/mm ²More than.In the Martens hardness of release layer less than 400N/mm ²The time, exist the peeling rate dependence of the peeling force of mold release film to increase and the film surface sustains damage easily and is easy to generate the unfavorable condition of OL etc.

Above-mentioned Martens hardness refers to the hardness that the penetration hardness test of the hardness measurement machine that adopt to use the triangular pyramid type pressure head, the instrument detectingization by the top layer is obtained, and is to measure the value that obtains with the test power of 115 ° of pyrometric cone pressure heads, 0.10mN.

Mold release film of the present invention according to purposes, exists in the situation that occurs foreign matter or interference of light look in the optical check etc. of operation.In order foreign matter or interference of light look to occur in optical check of reducing operation etc., it is vital making the MOR__C value optimization that gets with microwave mode molecular orientation instrumentation of mold release film.Be used to satisfy the means of scope of the MOR__C value of polyester film, be when the system film, desirable film thickness suitably to be selected stretching condition.

The MOR__C value of polyester film is generally 1.5～3.0, is preferably 1.8～2.7, more preferably 2.1～2.4.Greater than 3.0 o'clock, the unfavorable condition of interference of light look etc. perhaps appearred seeing easily in the lack of uniformity of release layer when optical check is arranged in the MOR__C value.Less than 1.5 o'clock, there is the problem of the rate that the manufactures a finished product variation etc. of mold release film itself in the MOR__C value.

Embodiment

Below, by embodiment the present invention is described in further detail, but the present invention is only otherwise exceed its main points, is not limited to following embodiment.In addition, assay method that uses among the present invention and evaluation method are as follows.

(1) mensuration of the limiting viscosity of polyester

Accurately weighing has been removed and immiscible other component of polymer of polyester and the polyester 1g of pigment, adds phenol/tetrachloroethane=50/50(weight ratio) mixed solvent 100ml make its dissolving, 30 ℃ of mensuration.

(2) mean grain size (d50: mensuration μ m)

The value of the accumulation (weight basis) 50% that the equivalent spherical that will use centrifugal type particle size distribution device (the system SA-CP3 of Shimadzu Scisakusho Ltd type) to record distributes is as mean grain size.

(3) transmissivity of polyester film is measured

With JIS-K7105 is benchmark, and the turbidimeter with integrating sphere NDH-300A that utilizes Japanese electric look industrial group to produce measures the full light transmittance of polyester film.

(4) the heat shrink rate of polyester film is measured

At longitudinally (abbreviating MD later on as) and horizontal cross direction (abbreviating TD later on as) with polyester film respectively with random length L(cm) sampling.Then, this sample was heated 5 minutes with 160 ℃ in baking oven, from baking oven, take out this sample determination length I(cm).This operation is carried out 3 times, adopted mean value as heat shrink rate value.Can calculate the heat shrink rate by following formula.

Heat shrink rate (%)=﹛ (L-I)/L ﹜ * 100

(5) catalytic amount is measured in the coating layer

Use SAICAS,, the cross section is exposed in the enterprising line tilt cutting of sample film.After this, use TOF-SIMS(flight time type quality analysis mass spectrum), obtain the catalytic amount that comprises platinum that contains in the polyester film coating layer.

(6) translate into the branch quantitative determination

Making that with dilution with toluene solid component concentration is among the organic siliconresin 15g of 4 weight %, add the 0.02 weight % platinum catalyst of 0.004g, stir the back, put into the case of making by the sheet of teflon (registered trademark) system, with 150 ℃ of heat curings 1 hour (sample 1).Translate into timesharing (being equivalent to comparative example 2 described later) in interpolation, add 30 weight % with respect to the solid constituent of organic siliconresin.Sample 1 was flooded 1 in toluene, the sample that takes out with 120 ℃ of dryings 30 minutes, is put and is chilled to room temperature (sample 2).Calculate by following formula and to translate into component.

Translate into weight * 100 of component (weight %)=(weight of the weight-sample 2 of sample 1) ÷ sample 1

(7) metastatic of mold release film is estimated bonding rate

Sample film is cut the A4 size,, pushed 2 hours with the condition of 60 ℃ of temperature, pressure 1MPa the thick biaxial stretch-formed PET film of the overlapping 75 μ m of stripping surface (Mitsubishi Chemical polyester film Co., Ltd. produces, DIAFOIL T100-75).The thick film of the 75 μ m that will push on this stripping surface is as the metastatic evaluated for film.Operate too for untreated PET film, push the thick biaxial stretch-formed PET film (together) of 75 μ m as the benchmark film.After the press surface of separately film is pasted jointing tape (Nitto Denko Corp produces, " No.31B "), be cut into the size of 50mm * 300mm after, be determined at room temperature and place peeling force after 1 hour." Ezgraph " that peeling force uses Shimadzu Seisakusho Ltd. to produce is at draw speed 0.3(m/min) condition under carry out 180 ° and peel off.

Metastatic is estimated bonding rate (%)=(peeling force of the peeling force ÷ benchmark film of metastatic evaluated for film) * 100

In the big film of metastatic, adhering to a large amount of organosilicons on the film of pushing, so the peeling force of jointing tape reduces, metastatic is estimated bonding rate (%) and is also descended.

(8) evaluation of the peeling force of mold release film (F)

Paste the single face of two sides jointing tape (day eastern electrician produces " No.31B ") on the release layer surface of sample film after, be cut into the size of 50mm * 300mm, then be determined at the peeling force of room temperature placement after 1 hour afterwards.Peeling force is used cupping machine (INTESCO company produces " INTESCO MODEL 2001 types "), with draw speed 300mm/ minute, carry out 180 ° with 10000mm/ minute condition again and peel off.Judge with following benchmark.

Peeling force in the time of＜300mm/ minute＞

〇: in the scope of 10～20mN/cm.

*: less than 10mN/cm or greater than 20mN/cm.

The comparison of the peeling force in the time of peeling force in the time of＜10000mm/ minute and 300mm/ minute＞

The value that utilization is obtained by following formula is judged.

(10000mm/ minute time peeling force (mN/cm)) ÷ (300mm/ minute time peeling force (mN/cm))

〇: below 2.5.

*: greater than 2.5.

(9) stripping feature

Estimate stripping feature according to the situation when the stacked film with adhesive linkage is peeled off mold release film.

〇: mold release film be can't see the phenomenon that bonding agent adheres to by strip off neatly on release layer.

△: mold release film is by strip off, but bonding agent adheres on release layer when peeling off with fast speed.

*: adhere on the bonding agent mold release film, properly strip off.

(10) hardness measurement of the coating surface of polyester film

Top layer to polyester film, the dynamic ultra micro low height meter (DUH-211) that uses Shimadzu Seisakusho Ltd. to produce, condition with pyrometric cone pressure head (115 ° of angles, Bie Erkeweiqi class between rib), test power 0.10mN, load maintenance speed 0.0060mN/sec., duration of load 2sec. is measured, by the compression distance of above-mentioned test power is calculated Martens hardness.Wherein, measuring number of times is 12 times, adopts their mean value.

(11) from the mensuration of the OL of fixed bed surface extraction

In advance nonheat-treated mold release film was heated 10 minutes with 180 ℃ in air.After this, this film that will carry out bakingout process as far as possible with upper opening in length and breadth to the inside surface driving fit of the case of 10cm, high 3cm, obtain box-formed shape.When coating layer was set, the coating aspect was inboard.Then, in the case made from said method, put into 4ml DMF(dimethyl formamide), place and reclaim DMF after 3 minutes.The DMF that reclaims is supplied to liquid chromatography (Shimadzu Seisakusho Ltd.'s production, LC-7A), obtain the OL amount among the DMF,, obtain film surface OL amount (mg/m the area of this value divided by the film that contacts with DMF ²).

Oligomer amount among the DMF is obtained (absolute calibration curve method) by the standard sample peak area and the ratio of the peak area of measuring the sample peak area.Making of standard sample divided the OL(that gets cyclic trimer in advance by accurate weighing), be dissolved among the DMF of accurate weighing and make.The concentration of standard sample is preferably the scope of 0.001～0.01mg/ml.Wherein, the condition of liquid chromatography is as follows.

Shift phase A: acetonitrile

Shift phase B:2% aqueous acetic acid

Post: Mitsubishi chemical Co., Ltd's production, " MCI GEL ODS 1HU "

Column temperature: 40 ℃

Flow velocity: 1ml/ minute

Detect wavelength: 254nm

(12) mensuration of the MOR__C value of utilizing microwave molecular orientation meter of polyester film

The microwave mode molecular orientation meter that uses prince's instrumentation machine Co., Ltd. to produce is obtained the MOR__C value by transmission microwave intensity image.

(13) mensuration of the MOR__C value of utilizing microwave molecular orientation meter of polyester film

The microwave mode molecular orientation meter that uses prince's instrumentation machine Co., Ltd. to produce is obtained the MOR__C value by transmission microwave intensity image.Judge with following benchmark.

〇: scope 2.0～2.5.

△: scope 1.5～1.9 or 2.6～3.0.

*: be lower than 1.5% or be higher than 3.0.

(14) practical characteristic

Visual inspection under the＜reflected light 〉

Consider the Polarizer inspection, on film, be coated with release agent, obtain mold release film with the condition of 120 ℃ of dryer temperature, linear velocity 30m/min, in the Width of this mold release film mode parallel with the axis of orientation of light polarizing film, by bonding agent mold release film and light polarizing film are connected airtight, make Polarizer.Visual observations Polarizer under the fluorescent light reflection is according to the visual inspection of following benchmark evaluation under reflected light.Wherein, when measuring, the sample that cuts out the A4 size is implemented.

Judgment standard

〇: inspectability is good.

△: almost no problem can the inspection.

*: inspectability is bad.

〇 and △'s is no problem in actual use level.

＜under Nicol crossed visual inspection＞

Consider the Polarizer inspection, on film, be coated with release agent, obtain mold release film with the condition of 120 ℃ of dryer temperature, linear velocity 30m/min, in the Width of this mold release film mode parallel with the axis of orientation of light polarizing film, by bonding agent mold release film and light polarizing film are connected airtight, make Polarizer.At this, when making above-mentioned Polarizer, between bonding agent and light polarizing film, sneak into 50/m ²The ferrous metal powder (foreign matter) with the above size of 50 μ m.On the releasing polarizer film of sneaking into foreign matter that operation obtains like this, Polarizer with the overlapping inspection usefulness of mode of axis of orientation and mold release film Width quadrature, from Polarizer one side irradiation white light, use the Polarizer visual observations from checking, whether finding the foreign matter of between bonding agent and light polarizing film, sneaking under the Nicol crossed according to following benchmark evaluation.Wherein, when measuring, with respect to the Width of the film that obtains, the sample that cuts out the A4 size from the total 3 at central portion and both ends is respectively implemented.

Judgment standard

〇: the foreign matter identification is good.

△: out of question basically, can recognize foreign matter.

*: the foreign matter identification is bad.

〇 and △'s is no problem in actual use level.

In above-mentioned judgment standard, what 〇 was above is the level that can use in actual use no problemly.

(15) comprehensive evaluation

Considering to make complete characteristics such as film, throughput rate, inspection characteristic estimates.Judge with following benchmark.

〇: can make goods when producing fully and supply with.

△: throughput rate is good, and the bad frequency in the optical check is few.

*: produce rate variance.Bad frequent generation in the optical check.

The polyester that uses in embodiment and comparative example is the polyester that following operation is prepared.

The manufacture method of＜polyester (a)＞

100 weight portion dimethyl terephthalate (DMT) and 60 weight portion ethylene glycol as initiation material, as catalyzer, are added four titanium butoxide acid esters and drop in the reactor, to react the beginning temperature and be made as 150 ℃, follow the distillation of methyl alcohol to remove, temperature of reaction is slowly risen, reach 230 ℃ after 3 hours.After 4 hours, ester exchange reaction is finished in fact after, carry out polycondensation reaction in 4 hours.

That is, temperature slowly being heated up from 230 ℃ is 280 ℃.On the other hand, pressure slowly descends from normal pressure, finally is 0.3mmHg.After the reaction beginning, the variation according to the stirring power of reactive tank stops reaction in the moment that is equivalent to limiting viscosity 0.61, adds at nitrogen and depresses the discharge polymkeric substance.Obtain the polyester (a) of limiting viscosity 0.61.

The manufacture method of＜polyester (b)＞

In the manufacture method of polyester (a), after adding acid phosphate ester, add the ethylene glycol slurry of the synthetic calcium carbonate particle of mean grain size 0.8 μ m, making particle is 1 weight % with respect to the content of polyester, and the same method of the manufacture method of use and polyester (a) obtains polyester (b) in addition.The limiting viscosity of resulting polyester (b) is 0.60.

The manufacturing of＜polyester (c)＞

100 weight portion dimethyl terephthalate (DMT) and 60 weight portion ethylene glycol as initiation material, as catalyzer, are added four hydration magnesium acetates and drop in the reactor, to react the beginning temperature and be made as 150 ℃, follow the distillation of methyl alcohol to remove, temperature of reaction is slowly risen, reach 230 ℃ after 3 hours.

After 4 hours, ester exchange reaction is finished in fact.After in this reaction mixture, adding acid phosphate ester, move into the polycondensation groove, add 0.04 part of antimony trioxide, carry out polycondensation reaction in 4 hours.That is, temperature slowly being heated up from 230 ℃ is 280 ℃.

On the other hand, pressure slowly descends from normal pressure, finally is 0.3mmHg.After the reaction beginning, the variation according to the stirring power of reactive tank stops reaction in the moment that is equivalent to limiting viscosity 0.45, adds at nitrogen and depresses the discharge polymkeric substance, obtains the sheet (c) of polyester.The limiting viscosity of this polyester is 0.45.

The manufacturing of＜polyester (d)＞

Utilize process for solid state polycondensation to improve the limiting viscosity of this polyester sheet.In the preparation crystallization tank, in 170 ℃ nitrogen atmosphere, handle after 0.5 hour, make the rower drier of inertness gas communication, being dried to moisture rate under 200 ℃ temperature is 0.005%.After this, send into the solid phase groove, carry out 3 hours solid phases with 240 ℃, obtain the polyester (d) of limiting viscosity 0.70.

The manufacturing of＜polyester (e)＞

When making polyester (d), in the solid phase groove, carry out 5 hours solid phases, obtain the polyester (e) of limiting viscosity 0.80.

Embodiment 1

(manufacturing of polyester film)

Raw material as the top layer, mix 70 weight % polyester (e) and 30 weight % polyester (b), raw material as the middle layer, mix 84 weight % polyester (a) and 16 weight % polyester (b), supply with to the extruder of 2 band ventilating openings respectively, after melt extruding with 290 ℃, use static to apply the driving fit method, be set in surface temperature on 40 ℃ the chill roll and carry out cooling curing, obtain not drawing sheet.Then, with 100 ℃ behind 2.8 times of longitudinal stretchings, in stenter through preheating procedure, with 120 ℃ of cross directional stretchs that apply 5.1 times, afterwards with 220 ℃ of thermal treatments of carrying out for 10 seconds, after this, laterally applying 4% laxly with 180 ℃, obtaining the home roll of wide 4000mm.Cut from the position apart from the end 1400mm of this home roll, the 1000m that reels on core obtains polyester film.The gross thickness of the film that obtains is 50 μ m(layer structure: 2.5 μ m/ middle layers, top layer, 45 μ m/ top layers, 2.5 μ m).

Utilize counter-rotating intaglio plate coating method on the polyester film that obtains, be coated with and forms-release agent that A constitutes, make that coating weight (after dry) is 0.12g/m by following release agent ², obtain the demoulding polyester film of roller shape with the condition of 120 ℃ of dryer temperature, linear velocity 30m/ minute.Peeling force 14mN/cm mold release film when the demoulding polyester film that obtains is 300mm/ minute speed, and the peeling force when 10000mm/ minute speed is 32mN/cm.

＜release agent composition-A＞

20 parts of curing type silicone resins (LTC303E:Dow Corning Toray production)

0.2 part of MEK/ toluene/n-heptane mixed solvent (blending ratio 1: 1: 1) of add-on type platinum catalyst (SRX212:Dow Corning Toray production)

The metastatic of release agent composition-A becomes component: 15 weight %

The polyester film that obtains is made Polarizer with following method, carries out the evaluation of the inspectability and the peel property of optical characteristics.The inspectability that the mold release film that obtains is undertaken by reflection is good, the foreign matter identification is good, and Polarizer peeled off neatly, can't see the phenomenon that bonding agent adheres on release layer.

＜have the manufacturing of the Polarizer of mold release film＞

The following acrylic adhesive of coating makes that dried thickness is 25 μ m on Polarizer, makes it to pass through pasting mold release film afterwards in 130 ℃ the drying oven 30 seconds, makes mold release film and the light polarizing film Polarizer that has mold release film by the bonding agent driving fit.The applying direction of film is that the Width of mold release film is parallel with the axis of orientation of light polarizing film.

(acrylic adhesive coating fluid)

100 parts of acrylic adhesives (production of Oribain BPS429-4:TOYO INK company)

3 parts in hardening agent (production of BPS8515:TOYO INK company)

50 parts of MEK/ toluene mixed solvents (blending ratio 1: 1)

Embodiment 2～4

In embodiment 1, stretching ratio, film thickness when changing the polyester film manufacturing change and contain the coating layer of polyvinyl alcohol (PVA), the coating weight of silicon-type release layer (dry back), change the component that translates into of release agent composition, operation is made similarly to Example 1 in addition, obtains polyester film.In following table 1, gather the result that expression obtains.

[table 1]

Comparative example 1

Except with the release agent change composed as follows, operate similarly to Example 1 and make, obtain polyester film.In following table 2, gather the result that expression obtains.

＜release agent composition B＞

Curing type silicone resin (KS-847H: SHIN-ETSU HANTOTAI's chemical production) 20 parts

Add-on type platinum catalyst (PL-50T: SHIN-ETSU HANTOTAI's chemical production) 0.2 part

MEK/ toluene/n-heptane mixed solvent (blending ratio 1: 1: 1)

The metastatic of release agent composition-B becomes component: 5 weight %

Comparative example 2

＜release agent composition-C＞

20 parts of curing type silicone resins (LTC303E:Dow Corning Toray production)

0.18 part of silicone oil (KS-64-100cs)

0.2 part of add-on type platinum catalyst (SRX212:Dow Corning Toray production)

MEK/ toluene/n-heptane mixed solvent (blending ratio 1: 1: 1)

The metastatic of release agent composition-C becomes component: 23 weight %

Comparative example 3

In embodiment example 1, with＜release agent composition-A＞coating weight is changed to 0.25g/m ², make with the 1 same operation of embodiment example in addition, obtain polyester film.In following table 2, gather the result that expression obtains.

Comparative example 4

In comparative example 1, with＜demoulding composition-C＞coating weight is changed to 0.08g/m ², make with comparative example 1 same operation in addition, obtain polyester film.In following table 2, gather the result that expression obtains.

Comparative example 5～9

In embodiment 1, the thickness when changing the polyester film manufacturing, change contains the coating weight (dry back) of the coating layer and the silicon-type release layer of polyvinyl alcohol (PVA), and operation manufacturing similarly to Example 1 obtains polyester film in addition.In following table 3, gather the result that expression obtains.

Comparative example 10

In embodiment 1, be coated on the coating fluid that adds 3 parts of silicone oil (AL-1) among the release agent composition-A, in addition, operation is made similarly to Example 2, obtains polyester film.In following table 3, gather the result that expression obtains.

［ table 2 ］

［ table 3 ］

Claims

1. mold release film is characterized in that:

This mold release film comprises the polyester film that possesses release layer, release layer sticked on the adhesive linkage of no base material two sides adhesive sheet to use,

Release layer is the silicon-type release layer, described release layer contains: have thiazolinyl as the organic siliconresin (a) of functional group, the transfer composition (c) and the platinum group catalyst (d) that have the organic siliconresin (b) of alkyl, shift to adhesive linkage, the content that shifts composition (c) is 5～20 weight %

The low speed peeling force of release layer when 300mm/ minute speed is the scope of 10～20mN/cm, and the high speed peeling force when 10000mm/ minute speed is below 2.5 times of low speed peeling force.

2. mold release film as claimed in claim 1 is characterized in that:

Between polyester film and silicon-type release layer, have coating and contain the coating fluid of polyvinyl alcohol (PVA) and the coating layer that obtains.

3. mold release film as claimed in claim 1 or 2 is characterized in that:

Transfer composition in the silicon-type release layer is an annular siloxane.

4. as each described mold release film in the claim 1～3, it is characterized in that:

The Martens hardness with the test power of 115 ° of pyrometric cone pressure heads, 0.10mN of silicon-type release layer is 400N/mm ²More than.

5. as each described mold release film in the claim 1～4, it is characterized in that:

The MOR__C value of polyester film is 1.5～3.0.