JP5511757B2 - Release film - Google Patents

Description

  The present invention relates to a mold release film used for molding an optical semiconductor element or a semiconductor element, in particular, for molding an LED lens.

  For example, optical semiconductor elements such as LEDs, photoisolators, phototransistors, photodiodes, CCDs, CMOSs, and semiconductor elements such as transistors, ICs, LSIs, and super LSIs are encapsulated with silicone rubber compositions or epoxy resin compositions. And is sealed by molding.

  A molding apparatus is used for sealing the above-described optical semiconductor element or semiconductor element, and a silicone rubber composition or an epoxy resin composition is filled into a mold as a sealing material and molded.

  As a method for releasing the mold and the molded product, for example, a method in which a release film is interposed between the mold and the sealing material to be filled has been put into practical use (see Patent Document 1). The release film is supplied Roll-to-Roll in the mold forming apparatus, enters the mold that is temperature-controlled at the molding processing temperature, is sucked in vacuum and is in close contact with the mold, and then filled with a sealing material Is done. When the mold is opened after a certain time, the molded product is peeled off from the mold release film while the mold release film is sucked into the mold. The release film includes, for example, a single layer made of a thermoplastic fluororesin tetrafluoroethylene-ethylene copolymer resin (ETFE resin) or a tetrafluoroethylene-hexafluoropropylene copolymer resin (FEP resin). A film is used (see Patent Document 2).

  However, when such a release film is used for molding an LED lens using a silicone rubber composition as a sealing material, for example, for a bullet-shaped lens shape having a bottom surface of about φ6 mm and a height of about 4 mm. Even if the release film is sucked in vacuum, it may not stretch, and even if it is stretched, it does not adhere to the mold, and there is a problem that an LED lens as designed can not be obtained. Further, if the release film is made thin and easily stretched, there is a problem that the release film is cut at the edge of the mold when sucked in vacuum.

  Moreover, the method of using the film which consists of a crystalline aromatic polyester containing resin composition which contains butylene terephthalate in a crystal | crystallization component is known as a mold release film (refer patent document 3).

  However, as shown in Patent Document 3, when a film made of a resin composition containing a crystalline aromatic polyester containing butylene terephthalate is used for molding an LED lens, the release film is sucked in vacuum as shown in Patent Document 3. In this case, although it adheres to the mold, it is stretched beyond the yield point, so that the release film is partially thinned, and there is a problem that irregularities and wrinkles occur on the surface of the molded LED lens. In addition, addition type liquid silicone rubber is used as the silicone rubber composition, but the compound present in the release film becomes a catalyst poison of the addition type liquid silicone rubber, which inhibits curing, and There is a problem that the contact surface does not cure and the gel-like adhesive remains. For this reason, in the molding of LED lenses using addition-type liquid silicone rubber, there is actually no film that can be suitably used as a release film.

JP-A-8-142105 JP 2001-310336 A JP 2007-224311 A

  The present invention has been made in view of the above, and is a mold release film that is excellent in releasability from a mold or a molded product in molding of an LED lens using an addition-type liquid silicone rubber. The shape is transferred to the molded product according to the design dimensions, and the mold shape transferability is excellent, and the surface smoothness of the molded product is obtained without the gel-like adhesive remaining on the surface of the molded product. It aims at providing the film for mold release which also has the heat resistance in use temperature.

  In order to solve the above-mentioned problems, the release film of the present invention comprises a polyurethane elastomer having a JIS A hardness of 70 or more and a Vicat softening temperature of 100 to 180 ° C., and a fluorine-containing alcohol compound and a fluorine-containing diol. It consists of a thermoplastic elastomer composition containing a compound selected from the group.

  Such an object is achieved by the present inventions (1) to (7) below.

  (1) JIS A One or more selected from the group consisting of a fluorine-containing alcohol compound and a fluorine-containing diol compound with respect to 100 parts by mass of a polyurethane elastomer having a hardness of 70 or more and a Vicat softening temperature of 100 to 180 ° C. A release film, which is a thermoplastic elastomer composition containing a plurality of compounds in the range of 0.1 to 5.0 parts by mass.

(2) The fluorine-containing alcohol compound is a compound represented by the general formula (A), and the fluorine-containing diol compound is a compound represented by the general formula (B). Release film.
Rf ₁ (CH ₂ ) _m OH (A)
(In the formula, Rf ₁ represents a linear or branched perfluoroalkyl group or perfluoroalkyl ether group having 3 to 20 carbon atoms, and m is 1 to 5.)
_{Rf 2 (CH 2) n OCH} 2 CH (OH) CH 2 OH ··· (B)
(In the formula, Rf ₂ represents a linear or branched perfluoroalkyl group having 3 to 20 carbon atoms, and n is an integer of 1 or 2.)

  (3) The thermoplastic elastomer composition further comprises one or more additives belonging to a lubricant, an antiblocking agent, a phenolic antioxidant, and a phosphorus antioxidant (1) or (2 ) Film for release.

(4) The tensile elastic modulus of the film is in the range of 10 to 500 N / mm ² in both the film longitudinal direction (MD) and the film transverse direction (TD), according to any one of (1) to (3) Mold release film.

  (5) Ratio (MD) / (TD) of film longitudinal direction (MD) and film transverse direction (TD) at 50% modulus (50% Mo) of the film is in the range of 0.9 to 1.2. The film for mold release in any one of (1)-(4) characterized by these.

  (6) The ratio (100% Mo) / (50% Mo) of 50% modulus (50% Mo) and 100% modulus (100% Mo) of the film is the film longitudinal direction (MD) and the film transverse direction (TD). Both are the range of 1.0-1.6, The film for mold release in any one of (1)-(5) characterized by the above-mentioned.

  (7) The film for release according to any one of (1) to (6), wherein the tensile elongation of the film exceeds 350% in both the film longitudinal direction (MD) and the film transverse direction (TD).

  According to the release film of the present invention, the mold and the molded product are excellent in peelability, and the mold shape is excellently transferred to the molded product according to the design dimensions. The surface smoothness of the molded product can be obtained without leaving a gel-like pressure-sensitive adhesive on the surface, and heat resistance can also be provided.

It is a side view of a bullet type LED lens concerning an embodiment of the present invention. (A) It is a top view of the metal mold | die of the bullet type LED lens which concerns on embodiment of this invention. (B) It is an AA arrow sectional view of Drawing 2 (a) of a metallic mold of a bullet type LED lens concerning an embodiment of the present invention. It is a figure which shows schematic structure of the film manufacturing apparatus of the film for mold release which concerns on embodiment of this invention. It is sectional drawing which shows the periphery of the material insertion hopper of the film manufacturing apparatus shown in FIG. 3 based on embodiment of this invention.

As a result of various studies to achieve the above object, the present inventors have determined that among polyurethane-based elastomers, JIS
A From a group consisting of a fluorine-containing alcohol compound and a fluorine-containing diol compound with respect to 100 parts by mass of a polyurethane elastomer having a hardness of 70 or more, a specific gravity of 1.05-1.30, and a Vicat softening temperature of 100-180 ° C. A release film comprising a thermoplastic elastomer composition containing one or more selected compounds in the range of 0.1 to 5.0 parts by mass is excellent in releasability from a mold or a molded product, and The mold shape is excellent in mold shape transferability that is transferred to the molded product according to the design dimensions, and the surface smoothness of the molded product can be obtained without any gel-like adhesive remaining on the surface of the molded product. It has been found that it can also have heat resistance.

  The polyurethane-based elastomer in the present invention is a thermoplastic polyurethane-based elastomer obtained by a reaction of three components of polyisocyanate, polyol and chain extender.

  Examples of the polyisocyanate include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylene-1,4-diisocyanate, xylene-1,3-diisocyanate, 4,4'-diphenylmethane diisocyanate, 2 , 4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, 2-nitrodiphenyl-4,4'-diisocyanate, 2,2'-diphenylpropane-4,4'-diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4,4'-diphenylpropane diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, naphthylene-1,4-dii Aromatic diisocyanates such as cyanate, naphthylene-1,5-diisocyanate, 3,3′-dimethoxydiphenyl-4,4′-diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, dodecane diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, etc. Aliphatic diisocyanates, cyclohexane diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, hydrogenated diphenylmethane diisocyanate, tetramethylxylene diisocyanate, norbornane diisocyanate methyl, and the above isocyanates The biuret , Dimers thereof, trimer, dimer, trimer, carbodiimide body, uretonimine body, can be mentioned adducts and the like obtained by the reaction of a bifunctional or higher functional polyols such as the isocyanate. Polyisocyanate in which a part of the isocyanate group is stabilized with a blocking agent having one active hydrogen in the molecule, such as methanol, n-butanol, benzyl alcohol, ethyl acetoacetate, ε-caprolactam, methyl ethyl ketone oxime, phenol, cresol, etc. Can also be mentioned. These can be used alone or in combination of two or more.

  The above-mentioned polyols are polymer polyols having a number average molecular weight of 500 to 10,000, and these include polyester polyols, polyester amide polyols, polycarbonate polyols, polyether polyols, polyether ester polyols, polyolefin polyols and the like. These polymer polyols can be used alone or in combination of two or more.

  Examples of the polyester polyol and polyesteramide polyol include those obtained by a condensation reaction from a polycarboxylic acid and a polyol, optionally in combination with a diamine or an amino alcohol.

  Examples of the polycarboxylic acid include oxalic acid, adipic acid, sebacic acid, dimer acid, hydrogenated dimer acid, phthalic acid, phthalic acid alkyl esters, trimellitic acid, maleic acid, fumaric acid, and itaconic acid. . Further, those obtained by ring-opening polymerization of cyclic esters such as butyrolactone, valerolactone and caprolactone are also included.

  Examples of the polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentane. Diol, 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8- Octanediol, 1,9-nonanediol, 2,2-diethyl-1,3-propanediol, 2-n-butyl-2-ethyl-1,3-propanediol, 2,2,4-trimethyl-1, 3-pentanediol, 2-ethyl-1,3-hexanediol, 2-n-hexadecane-1,2-ethylene glycol, 2-n-eico 1,2-ethylene glycol, 2-n-octacosane-1,2-ethylene glycol, diethylene glycol, dipropylene glycol, 1,4-cyclohexanedimethanol, or ethylene oxide or propylene oxide adduct of bisphenol A, hydrogenation Low molecular polyols such as bisphenol A, 3-hydroxy-2,2-dimethylpropyl-3-hydroxy-2,2-dimethylpropionate, trimethylolpropane, glycerin, pentaerythritol and the like can be mentioned. Examples of the diamine or amino alcohol include low molecular polyamines such as ethylenediamine, hexamethylenediamine, xylylenediamine, and isophoronediamine, and low molecular amino alcohols such as monoethanolamine, diethanolamine, and triethanolamine. Furthermore, lactone polyester polyols obtained by ring-opening polymerization of cyclic ester (lactone) monomers such as ε-caprolactone and γ-valerolactone using low molecular polyols, low molecular polyamines, and low molecular amino alcohols as initiators.

  Examples of the polycarbonate polyol include those obtained by a dealcoholization reaction, a dephenol reaction, or the like of a low molecular polyol used for the synthesis of the polyester polyol described above and diethylene carbonate, dimethyl carbonate, diethyl carbonate, diphenyl carbonate, or the like.

  As the polyether polyol, polyethylene glycol, polypropylene glycol obtained by ring-opening polymerization of ethylene oxide, propylene oxide, tetrahydrofuran, etc., using the low molecular polyol, low molecular polyamine, and low molecular amino alcohol used in the above polyester polyol as an initiator, Examples thereof include polytetramethylene ether glycol and the like, polyether polyols obtained by copolymerization thereof, and polyester ether polyols using the above-described polyester polyols and polycarbonate polyols as initiators.

  Examples of the polyether ester polyol include those obtained in the same manner as the polyester polyol except that the polyether is used for a part or all of the polyol used in the condensation reaction for obtaining the polyester polyol.

  Examples of the polyolefin polyol include hydroxyl group-containing polybutadiene, hydrogenated hydroxyl group-containing polybutadiene, hydroxyl group-containing polyisoprene, hydrogenated hydroxyl group-containing polyisoprene, hydroxyl group-containing chlorinated polypropylene, and hydroxyl group-containing chlorinated polyethylene.

  The chain extender is an active hydrogen-containing compound having a number average molecular weight of less than 500, and examples thereof include the low molecular polyols, the low molecular polyamines, and the low molecular amino alcohols.

  For the production of the polyurethane-based elastomer, a known production method such as a one-shot method, a prepolymer method, a batch reaction method, a continuous reaction method, a kneader method or an extruder method can be employed.

  As for the hardness of the polyurethane elastomer used in the present invention, the JIS A hardness measured by the test method of JIS K 7311 is 70 or more. Furthermore, when the JIS A hardness is 100 or more, it is preferable that the D hardness is applied and the upper limit is 70 or less of the D hardness. The JIS A hardness is preferably 80 or more, more preferably 90 or more. When the JIS A hardness is less than 60, the rubber property becomes strong, and therefore, when the release film is transported in the molding apparatus, the release film is stretched and the transport is not stable. On the other hand, when the D hardness exceeds 70, there is a problem that a gel derived from three components of the raw material polyisocyanate, polyol and chain extender is generated during extrusion molding.

  The Vicat softening temperature of the polyurethane elastomer used in the present invention is measured by the test method of JIS K7206 and is in the range of 100 to 180 ° C. The Vicat softening temperature is preferably 110 to 180 ° C, more preferably 120 to 180 ° C, and still more preferably 130 to 180 ° C. If the Vicat softening temperature is less than 100 ° C., there is a problem of melting during use. That is, heat resistance cannot be obtained. On the other hand, the upper limit of the Vicat softening temperature is 180 ° C., but a polyurethane elastomer having a Vicat softening temperature exceeding 180 ° C. has not been obtained.

In the present invention, the fluorine-containing alcohol compound is Rf ₁ (CH ₂ ) _m OH (wherein Rf ₁ is a linear or branched perfluoroalkyl group having 3 to 20 carbon atoms or a perfluoroalkyl group as a general formula (A). Represents a fluoroalkyl ether group, and m is 1 to 5.). Specific examples thereof include C ₆ F ₁₃ CH ₂ OH, C ₇ F ₁₅ CH ₂ OH, C ₈ F ₁₇ CH ₂ OH, C ₈ F ₁₇ CH ₂ CH ₂ OH, C ₉ F ₁₉ CH ₂ CH ₂ OH, _{C 10 F 21 CH 2 CH 2} OH, (CF 3) 2 CF (CF 2) 8 CH 2 CH 2 OH, CF 3 CF 2 O (CF 2 CF 2 O) 1~5 CF 2 CH 2 OH, CF 3 _{CF 2 CF 2 O (CFCF 3} CF 2 O) 1~3 CFCF 3 CH 2 OH , and the like. among these, _C 6 _F 13 _CH 2 OH containing linear perfluoroalkyl group, _{C 7 F 15 CH 2 OH, C 8} F 17 CH 2 OH, C 8 F 17 CH 2 CH 2 OH, C 9 F 19 CH 2 CH 2 OH, is _{C 10 F 21 CH 2 CH 2} OH preferable.

The fluorine-containing diol compound in the present invention is Rf ₂ (CH ₂ ) _n OCH ₂ CH (OH) CH ₂ OH (wherein Rf ₂ is linear or branched having 3 to 20 carbon atoms) as the general formula (B). Wherein n is an integer of 1 or 2.). Specific examples thereof include C ₆ F ₁₃ CH ₂ CH ₂ OCH ₂ CH (OH) CH ₂ OH, C ₇ F ₁₅ CH ₂ CH ₂ OCH ₂ CH (OH) CH ₂ OH, C ₈ F ₁₇ CH ₂ CH _{2. OCH 2 CH (OH) CH 2} OH, C 9 F 19 CH 2 CH 2 OCH 2 CH (OH) CH 2 OH, C 10 F 21 CH 2 CH 2 OCH 2 CH (OH) CH 2 OH, (CF 3) ₂ CF (CF ₂ ) ₈ CH ₂ CH ₂ OCH ₂ CH (OH) CH ₂ OH and the like, and among these, C ₆ F ₁₃ CH ₂ CH ₂ OCH ₂ containing a linear perfluoroalkyl group _{CH (OH) CH 2 OH,} C 7 F 15 CH 2 CH 2 OCH 2 CH (OH) CH 2 OH, C 8 F 17 CH 2 CH 2 OCH 2 CH (OH) CH 2 OH, C 9 F 19 CH 2 CH ₂ O CH ₂ CH (OH) CH ₂ OH, C ₁₀ F ₂₁ CH ₂ CH ₂ OCH ₂ CH (OH) CH ₂ OH are preferred.

  The fluorine-containing alcohol compound and the fluorine-containing diol compound (hereinafter abbreviated as fluorine-containing alcohol compound / diol compound) are mixed with the polyurethane elastomer for the purpose of imparting lubricity to the release film. By mixing these fluorine-containing alcohol compounds and diol compounds, lubricity is imparted to the film surface, so that the film can be transported smoothly in the mold forming apparatus, and when the mold comes in contact with the mold. The effect of preventing wrinkles of the mold film and the effect of improving the peelability from the silicone rubber composition used as the sealing material are obtained.

  Moreover, the polyisocyanate which is the component remains in the film which consists only of a polyurethane-type elastomer, and this will become a catalyst poison of addition type liquid silicone rubber, and will inhibit hardening. However, when a fluorine-containing alcohol compound / diol compound is mixed with a polyurethane elastomer, it reacts with polyisocyanate to bond a perfluoroalkyl group to the main skeleton of the polyurethane elastomer and to eliminate the catalyst poison. As a result of this action, a film made by mixing a fluorine-containing alcohol-based compound / diol compound with a polyurethane-based elastomer can be cured by a catalyst poison even if it is used as a release film for molding an addition-type liquid silicone rubber composition. No inhibition occurs, and no gel-like adhesive remains on the surface of the molded product.

  The mixing amount of one or a plurality of compounds selected from the group consisting of a fluorine-containing alcohol compound and a fluorine-containing diol compound is in the range of 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the polyurethane elastomer. . When the mixing amount is less than 0.1 parts by mass, the mixed effect does not appear. On the other hand, mixing over 5.0 parts by mass does not increase the effect, and these fluorine-containing alcoholic compounds and diol compounds remain unreacted and bleed out on the film surface to contaminate the surface of the molded product. There is a bug to do.

  The thermoplastic elastomer composition of the present invention can be mixed with other thermoplastic elastomers as long as the characteristics of the present invention are not impaired. Examples of the thermoplastic elastomer include polyester elastomers, polyamide elastomers, polyvinyl chloride elastomers, styrene elastomers, and olefin elastomers.

  The thermoplastic elastomer composition of the present invention includes, for example, a lubricant such as an amide wax, an anti-blocking agent such as silica, a phenolic antioxidant, a phosphorus antioxidant, etc., as long as the characteristics of the present invention are not impaired. Can be mixed.

The release film in the present invention has a tensile modulus of 10 measured in accordance with JIS Z 1702 at a temperature of 23 ° C. and a tensile speed of 100 mm / min, both in the film longitudinal direction (MD) and the film transverse direction (TD). The range is from 0.0 to 500 N / mm ² . This tensile modulus is preferably in the range of 20.0 to 400 N / mm ² , more preferably in the range of 30.0 to 300 N / mm ² . When the tensile elastic modulus is less than 10.0 N / mm ² , when the release film is pulled out from the wound body in the molding apparatus, there is a problem that the film is weak and loose. On the other hand, when the tensile modulus exceeds 500 N / mm ² , when the release film is sucked in a vacuum in the mold, there is a problem that the film does not stretch and does not adhere to the mold.

  In the present invention, the release film is a film longitudinal direction (MD) and a film transverse direction (50% modulus (50% Mo) of the film measured at a temperature of 23 ° C. and a tensile speed of 100 mm / min in accordance with JIS Z 1702. The ratio (MD) / (TD) to TD) is in the range of 0.90 to 1.20. This (MD) / (TD) is preferably in the range of 0.95 to 1.20. (MD) / (TD) does not become less than 0.90 in a film formed by an extrusion method. On the other hand, when (MD) / (TD) exceeds 1.20, there is a problem that wrinkles are generated in the film when the release film is supplied to the mold in the molding apparatus.

  The release film in the present invention is a ratio of 50% modulus (50% Mo) to 100% modulus (100% Mo) of a film measured at a temperature of 23 ° C. and a tensile speed of 100 mm / min in accordance with JIS Z 1702 ( 100% Mo) / (50% Mo) is in the range of 1.00 to 1.60 for both the film longitudinal direction (MD) and the film transverse direction (TD). This (100% Mo) / (50% Mo) is preferably in the range of 1.00 to 1.50. When (100% Mo) / (50% Mo) is less than 1.00, no increase in the stress accompanying the increase in film elongation occurs, so uniform film elongation cannot be obtained, and the mold release film is a mold. There is a problem that wrinkles occur when sucked in by vacuum. On the other hand, when (100% Mo) / (50% Mo) exceeds 1.60, the increase in stress accompanying the increase in film elongation is large, and the film is fully extended until the release film adheres to the inner surface of the mold. There is no fault.

  In the release film of the present invention, the tensile elongation of the film measured at a temperature of 23 ° C. and a tensile speed of 100 mm / min in accordance with JIS Z 1702 is 350% in both the film longitudinal direction (MD) and the film transverse direction (TD). That's it. This tensile elongation is preferably 400% or more. When the tensile elongation is less than 350%, there is a problem that the release film is cut at the edge of the mold when sucked in vacuum in the mold.

  Production of a thermoplastic elastomer composition comprising a polyurethane elastomer and a fluorine-containing alcohol compound / diol compound according to the present invention comprises: (1) a polyurethane elastomer and a fluorine-containing alcohol compound / diol compound at a temperature below the melting point of the elastomer; And a method of preparing a thermoplastic elastomer composition by dispersing and mixing a polyurethane elastomer and a fluorine-containing alcohol compound / diol compound. There is a method in which a thermoplastic elastomer composition is prepared by adding a fluorine-containing alcohol-based compound / diol compound to a polyurethane-based elastomer melted at a temperature equal to or higher than the melting point without melting, and kneading. Can be used

  Hereinafter, the method (1) will be described. Stirring and mixing of the polyurethane-based elastomer and the fluorine-containing alcohol-based compound / diol compound can be performed using a known mixer such as a tumbler mixer, a Henschel mixer, a ribbon blender, or a universal stirring mixer.

  The thermoplastic elastomer composition comprising a polyurethane elastomer and a fluorine-containing alcohol compound / diol compound is prepared by melting the stirring mixture prepared by the above method using an extruder such as a single screw extruder or a twin screw extruder. It is carried out by kneading. The temperature of the extruder when producing this thermoplastic elastomer composition is not lower than the melting point of the polyurethane elastomer and not higher than 240 ° C.

  Hereinafter, the method (2) will be described. After the polyurethane elastomer is melted by a melt kneader such as a single screw extruder or a twin screw extruder, a fluorine-containing alcohol compound / diol compound is added and melt kneaded to prepare a thermoplastic elastomer composition. The temperature of the extruder when producing this thermoplastic elastomer composition is not lower than the melting point of the polyurethane elastomer and not higher than 240 ° C.

  When a thermoplastic elastomer composition comprising a polyurethane elastomer and a fluorine-containing alcohol compound / diol compound is produced using an extruder such as a single screw extruder or a twin screw extruder, a film described later is formed. Similarly to the above, melt-kneading may be performed in an inert gas atmosphere in which air existing in the voids between the extruder and the composition is replaced with an inert gas.

  Usually, a thermoplastic elastomer composition is processed into a powder, granule, or pellet by a pulverizer or a cutter.

The release film comprising the thermoplastic elastomer composition described above can be formed by a conventionally known method such as a melt extrusion method or a melt cast method.
In the following example, a method for forming a release film by a melt extrusion method using a T-die will be described.

  The release film obtained by such a method uses a molding material of the thermoplastic elastomer composition, an extruder such as a single-screw extruder or a twin-screw extruder, according to the characteristics of the thermoplastic elastomer composition. In an atmosphere where the air in the gap between the extruder and the molding material is replaced with nitrogen gas, it is melt-kneaded and the release film melt-extruded from the lip portion at the tip of the T die placed at the tip of the extruder is taken up. Cool by pinching directly between the crimping roll and the cooling roll in the machine, or by inserting a separator from both or one side of the crimping roll and the cooling roll, and then cooling it. It is obtained by winding up sequentially.

  FIG. 3 is a configuration diagram showing an outline of a film production apparatus for producing a release film by the above-described method. 4 is a cross-sectional view of the periphery of the material charging hopper of the film manufacturing apparatus shown in FIG. In FIG. 3, the film manufacturing apparatus is generally configured to include a material charging hopper 2, an extruder 1, a T die 7, a take-up machine 11, and a winder 15. The material charging hopper 2 is configured to input a molding material, and as shown in FIG. 4, the nitrogen gas supply pipe 3 is connected to the extruder 1 of the material charging hopper 2 through the spacer 3a while being connected to the extruder 1. Inserted. The nitrogen gas supply pipe 3 is bent so as to be substantially along the central axis of the material charging port 1 c, and the tip thereof extends to the vicinity of the outer periphery of the extrusion screw 1 a in the extruder 1. Oxygen contained in the molding material fed from the material feeding hopper 2 or in the extruder 1 is supplied to the nitrogen gas supply pipe 3 when the molding material is mixed and stirred by the extrusion screw 1a of the extruder 1. It will be replaced with nitrogen gas.

  The extruder 1 mixes and stirs the molding material with the extrusion screw 1a, conveys it in the direction of arrow B, and heats and melts the molding material by electric heating means incorporated in the cylinder 1b of the extruder 1. The molding material thus melted and conveyed is fed to the filter means 5 through the connecting pipe 4 shown in FIG. The unmelted molding material is separated by the filter means 5 and the molten molding material is fed to the gear pump 6. In the gear pump 6, the molten molding material is pushed out to the T die 7 while increasing the pressure of the molten molding material. In the T die 7, the melt molding material is extruded at a predetermined pressure, and a film 8 having a predetermined thickness and a predetermined width is formed from the lip portion 7 a of the T die 7. The film 8 formed in this manner is adjusted to a predetermined thickness by the pressure-bonding roll 9 while being drawn on the outer peripheral surface of the cooling roll 10 of the take-up machine 11, and further cooled and solidified. It is conveyed to the winder 15.

  In the winder 15, the film 8 is guided by the guide rolls 15 a, 15 b, and 15 c and is wound by the winding tube 16. In addition, a thickness measuring device 14 is disposed between the conveying roll pairs 12 and 13 and the guide roll 15a, and the thickness measured by the thickness measuring device 14 is set so as to obtain a desired thickness. Based on this, the peripheral speed of the cooling roll 10 is adjusted and controlled. Thereby, the release film is formed.

  The release film may be formed in the surface shape of the film according to the surface shape required by the molded product. For example, when the surface of the LED or the like is a mirror surface, a release film in which the surface of the release film is a mirror surface is used. In addition, since ICs, LSIs, and the like have fine irregularities formed on the surface thereof, a release film having fine irregularities formed on the surface of the release film is used.

  As a method of forming the surface shape of the mold release film, when the surface is mirror-finished, the surface of the metal cooling roll described above is mirror-finished, and the mold release film in a molten state is placed on the cooling roll. There is a method in which the surface of the release film is mirror-finished by pressure bonding with a pressure roll. When using a separator, there is a method of using a mirror-finished PET film or OPP film as the separator and transferring the surface thereof.

  When forming fine irregularities on the surface of the mold release film, fine irregularities are formed on the outer peripheral surface of the metal cooling roll described above, and the mold release film in a molten state is pressure-bonded to the cooling roll. There is a method of transferring fine irregularities formed on the outer peripheral surface of the cooling roll onto the surface of the release film when crimping with a roll. Moreover, when using a separator, there exists the method of using the PET film and OPP film which carried out the mat processing of the surface as a separator, and transferring the surface.

  When the surface of the release film is a mirror surface, the surface roughness is measured at a speed of 0.6 mm / second, a cutoff value of 0.8 mm, and an evaluation length of 8.0 mm in accordance with JIS B0601-2001. The surface may be appropriately formed so that the arithmetic average roughness Ra is 0.10 or less and the maximum height roughness Rz is 1.00 or less. When the arithmetic average roughness Ra is 0.10 or less and the maximum height roughness Rz is 1.00 or less, the surface of the molded product to which the surface of the release film is transferred becomes smooth.

  When fine irregularities are formed on the surface of the release film, the arithmetic average roughness Ra measured by the same method as described above is 0.5 or more, and the maximum height roughness Rz is 5.00 or more. The surface may be appropriately formed so that

  The release film of the present invention has a thickness in the range of 5 μm to 500 μm, preferably in the range of 10 μm to 400 μm, and may be appropriately selected according to the shape of the mold to be used. If the thickness of the release film is less than 5 μm, when following the mold during use, the release film will be stretched and thinned, or it may be broken by the pressure of the sealing material. It is not preferable. If the thickness exceeds 500 μm, the thickness of the release film becomes an obstacle, and it becomes impossible to follow a mold having a fine structure, or the complicated shape of the mold cannot be transferred to the molded product. It is not preferable.

Examples of the release film of the present invention will be described below with reference to Tables 1 and 2.
The release film according to the present invention is not limited to Examples 1 to 8.
Here, the following materials are used for the polyurethane elastomer 1, the fluorine-containing alcohol compound / diol compound 1 and the fluorine-containing alcohol compound / diol compound 2 shown in Tables 1 and 2.

(Polyurethane elastomer 1)
Miractolan E598PNAT: trade name, manufactured by Nippon Polyurethane Industry Co., Ltd., JIS
A Hardness 98, Vicat softening temperature 141 ° C
(Fluorine-containing alcohol compound / diol compound 1)
F-top MF-100: trade name, manufactured by Mitsubishi Materials Corporation, 3- (2-perfluorohexylethoxy) -1,2-dihydroxypropane (C ₆ F ₁₃ CH ₂ CH ₂ OCH ₂ CH (OH) CH ₂ OH)
(Fluorine-containing alcohol compound / diol compound 2)
F-top PDFOH: trade name, manufactured by Mitsubishi Materials Corporation, pentadecafluorooctanol (C ₇ F ₁₅ CH ₂ OH)

  Hereinafter, the production of a release film, peelability, heat resistance, mold size transferability, presence / absence of a gel-like adhesive, surface smoothness and actual usability will be described in detail based on Tables 1 and 2. In addition, it is the content applied similarly also in Comparative Examples 1-5 of Tables 3-4.

(Preparation of release film)
The thermoplastic elastomer composition was supplied to a single screw extruder (manufactured by IK Corporation) having a diameter of 40 mm and L / D = 25, and a cylinder temperature of 180 ° C. or higher was used using a full flight extrusion screw having a compression ratio of 2.5. The mixture was melt-kneaded under a condition of 210 ° C. and continuously extruded from a T die having a width of 400 mm under a condition of a die temperature of 210 ° C. to 220 ° C. In the take-off machine, the extruded release film is supplied from the pressure-rolling roll side as a mat-processed PET film as a separator and from the cooling roll side as a mirror-finished PET film as a separator, and is sandwiched between the pressure-rolling roll cooling rolls. In the winder, both ends are cut with a slit blade, and the release film is wound on a winder tube, thereby having a thickness of 250 mm and a length of 50 m with the thicknesses shown in Tables 1 to 3. A release film was produced. These release films were left to stand for 24 hours in an atmosphere at 80 ° C., and then left for 168 hours in an atmosphere at 40 ° C. for aging. After the aging was completed, the release film was rewound while peeling off the separator mat-processed PET film and the mirror-processed PET film to obtain a release film for evaluation.

(Method of evaluation)
FIG. 1 is a side view of a bullet-type LED lens 20 having lead wires 21a and 21b. Evaluation is performed using the mold shown in FIGS. 2A and 2B having the lens shape shown in FIG. 1, and a release film is formed on the surface of the mold 30 along the plurality of lens molding recesses 31. After adsorbing, the silicone rubber composition was dropped and subjected to hot press molding, and peelability, heat resistance, mold size transferability, presence or absence of a gel-like adhesive, and surface smoothness were evaluated.

Specifically, the release film is stretched over the mold so that the matte surface of the release film is on the mold side and the mirror surface is on the air side, and the mold is removed by vacuum suction. It was made to adsorb to. Next, a silicone rubber composition OE-6636 (trade name, manufactured by Toray Dow Corning Co., Ltd.) is dropped on the release film, and a flat mold whose surface is hard chrome plated is pressed against these two molds. And then hot press-molded. Evaluates the peelability of the molded laminate from the release film and the cured silicone rubber, the heat resistance of the release film, the mold size transferability of the cured silicone rubber, the presence of gel-like adhesives, and the surface smoothness. did. Hot press molding was performed under conditions of a temperature of 140 ° C. and a pressure of 10 kg / cm ² for 5 minutes.

(Peelability)
Evaluation of peelability was "○" when the molded silicone rubber composition could be peeled without remaining on the release film, and the silicone rubber composition was partially broken and remained on the release film. The case is shown as “×”.

(Heat-resistant)
The evaluation of heat resistance was performed by visually observing the release film from which the molded silicone rubber composition was peeled off. If the film shape was maintained without melting or fusing, “○”, melted into the release film, The case where fusing occurred was indicated as “x”.

(Mold dimension transferability)
The mold dimension transferability was evaluated by measuring the dimensions of the molded silicone rubber composition. The lens height evaluation criteria is further within a range of -0.1 mm from the dimension obtained by reducing the thickness of the release film for a hole depth of 4 mm, that is, ((4-release film thickness) -0. .1) mm or more. A case where all the 25 lenses were within the standard was indicated by “◯”, and a case where even one lens did not satisfy the standard was indicated by “X”.

(Presence or absence of gel-like adhesive)
The presence or absence of the gel-like adhesive was confirmed by touching the surface of the molded silicone rubber composition with a finger and confirming the adhesive feeling. The case where there was no adhesion on the surface of the silicone rubber and no fingerprint was attached when the finger was released was evaluated as “◯”, and the case where the surface was adhesive and the fingerprint was attached when the finger was released was evaluated as “X”.

(Surface smoothness)
For the surface smoothness, the surface state of the molded silicone rubber composition was visually evaluated. The case where there was no unevenness or wrinkles on the surface of the silicone rubber was indicated as “◯”, and the case where there were unevenness or wrinkles was indicated as “x”.

(Actual usability)
The actual usability was confirmed and evaluated by resin molding with a molding apparatus. Specifically, OE-6636 (trade name, manufactured by Toray Dow Corning Co., Ltd.) was used as a silicone rubber composition in a molding apparatus G-LINE manual press (trade name) manufactured by Apic Yamada as a molding device. Usability was confirmed visually.

  The evaluation of actual usability is that the film is supplied without loosening when the release film is transported in the mold forming apparatus, the film is not wrinkled at the time of adsorption, and after hot press molding, the release film The surface of the cured silicone rubber composition is smooth and free of gel-like adhesives, and the release film is torn or melted. A state where there was no residue and the mold was not soiled was indicated as “◯”, and a case where there was a defect was indicated as “X”.

From these results, in Comparative Example 1, the mixing amount of the fluorine-containing alcohol compound / diol compound in the thermoplastic elastomer composition was less than the mixing amount of the present invention, but the gel-like adhesive remained on the surface of the molded product. There was a bug. In Comparative Example 2, the fluorine-containing alcohol compound / diol compound of the thermoplastic elastomer composition was mixed in excess of the mixing amount of the present invention, but the oil bleeded out from the release film adhered to the surface of the molded product. was there. In Comparative Example 3, an ETFE film manufactured by Asahi Glass Co., Ltd. and Aflex (trade name) having a thickness of 100 μm were used as comparative objects. However, the mold size transferability was inferior and practical useability was not obtained. In Comparative Example 4, an ETFE film manufactured by Asahi Glass Co., Ltd. and Aflex (trade name) having a thickness of 25 μm were used for comparison, but the film was broken when adsorbed in a mold, and actual usability was not obtained. It was. In Comparative Example 5, Hytrel 5577 (trade name) manufactured by Toray DuPont, polyester / polyether copolymer, D
A 50 μm-thick release film made of a thermoplastic elastomer composition having a hardness of 55 and a Vicat softening temperature of 192 ° C. was used as a comparison object. Wrinkles were generated on the surface of the molded article made of the silicone rubber composition, the surface smoothness was inferior, and there was also a gel-like pressure-sensitive adhesive, so that practical useability was not obtained.

  On the other hand, the release film of each example according to the present invention has heat resistance in addition to having releasability, excellent mold size transferability, and surface smoothness without leaving a gel-like adhesive. It is clear that the performance is obtained and that the actual usability is given. From this, according to the present invention, it is possible to obtain a release film that is excellent in releasability from a molded product obtained by molding a sealing material and that can provide a molded product having excellent shape and surface properties. it can.

  As mentioned above, although this invention was demonstrated using embodiment, it cannot be overemphasized that the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiments. Further, it is apparent from the scope of the claims that embodiments with such changes or improvements can also be included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Extruder 2 Material input hopper 3 Nitrogen gas supply pipe 4 Connection pipe 5 Filter 6 Gear pump 7 T die 7a Lip part 8 Film 9 Crimp roll 10 Cooling roll 11 Take-up machine 12, 13 Conveying roll pair 14 Thickness measuring device 16 rolls Pipes 17a, 17b Delivery rolls 18a, 18b Separator 20 Cannonball type LED lenses 21a, 21b Lead wire 30 Mold die 31 Lens molding recess

Claims (7)

One or more compounds selected from the group consisting of a fluorine-containing alcohol compound and a fluorine-containing diol compound with respect to 100 parts by mass of a polyurethane elastomer having a JIS A hardness of 70 or more and a Vicat softening temperature of 100 to 180 ° C. It consists of a thermoplastic elastomer composition containing 0.1 to 5.0 parts by mass of a release film. 2. The release compound according to claim 1, wherein the fluorine-containing alcohol compound is a compound represented by the general formula (A), and the fluorine-containing diol compound is a compound represented by the general formula (B). Mold film.
Rf ₁ (CH ₂ ) _m OH (A)
(In the formula, Rf1 represents a linear or branched perfluoroalkyl group or perfluoroalkyl ether group having 3 to 20 carbon atoms, and m is 1 to 5.)
_{Rf 2 (CH 2) n OCH} 2 CH (OH) CH 2 OH ··· (B)
(In the formula, Rf ₂ represents a linear or branched perfluoroalkyl group having 3 to 20 carbon atoms, and n is an integer of 1 or 2.) 3. The thermoplastic elastomer composition according to claim 1, further comprising one or more additives belonging to a lubricant, an anti-blocking agent, a phenol-based antioxidant, and a phosphorus-based antioxidant. 4. Release film. The mold release according to any one of claims 1 to 3, wherein the tensile modulus of the film is in the range of 10 to 500 N / mm ² in both the film longitudinal direction (MD) and the film transverse direction (TD). Film. The ratio (MD) / (TD) between the film longitudinal direction (MD) and the film transverse direction (TD) at 50% modulus (50% Mo) of the film is in the range of 0.9 to 1.2. The film for mold release according to any one of claims 1 to 4. The ratio (100% Mo) / (50% Mo) of 50% modulus (50% Mo) to 100% modulus (100% Mo) of the film is 1. in both the film longitudinal direction (MD) and the film transverse direction (TD). It is the range of 0-1.6, The film for mold release of any one of Claims 1-5 characterized by the above-mentioned. The film for mold release according to any one of claims 1 to 6, wherein the tensile elongation of the film exceeds 350% in both the film longitudinal direction (MD) and the film transverse direction (TD).

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