JP2009040895A - Mold release film and laminated body using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold release film with excellent mold releasability and improved writing properties without a coating process of a silicone compound containing organic solvent. <P>SOLUTION: This mold release film with improved writing properties is manufactured and used which is obtained by making contact at least one type of rubber selected from the group consisting of acrylic rubber, natural rubber, polyisoprene rubber, styrene rubber, and butyl rubber with the surface of the mold release film made of a mold releasable resin composition constituted by 93-99.99 wt.% of olefin polymers and 0.01-7 wt.% of polydimethylsiloxane for 240 hours or longer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a release film containing a release resin composition. More specifically, the present invention relates to a release film with improved writing properties on the surface of the release layer without impairing excellent release properties with respect to an adhesive or the like.

  The release film is a film-like material provided with a release surface that is laminated on the adhesive surface to protect the adhesive surface of the adhesive material when not in use, and is easily peeled without damaging the adhesive surface when in use. Widely used as a mount for adhesive tapes and labels. The release film usually includes a base material and a release layer containing a release agent provided on at least one surface of the base material. Paper, plastic film, etc. are used for the base material, and a silicone compound, a long-chain alkyl group-containing compound, etc. are used for the release agent. In such a release film, when the release agent is not sufficiently adhered to the substrate, the release agent is transferred to the adhesive surface of the tape or label when the tape or label is peeled off from the release film. And the stickiness of the label may be deteriorated.

  For this reason, as a method for producing a release film, a method in which a release agent such as vinyl group-containing polydimethylsiloxane is coated on a substrate and then the release agent is cured is generally used. However, in this method, there are problems that a large amount of an organic solvent is used to uniformly apply the release agent, and that the base material is exposed to a high temperature when the release agent is cured, so that pinholes are generated. It was.

  For this reason, a method for imparting releasability to a plastic as a base material instead of a coating method has been proposed.

  Therefore, the present inventor, as a method of imparting releasability to the plastic as a base material instead of a method of coating, a resin composition containing a small amount of polydimethylsiloxane showing a specific epoxy equivalent to an olefin polymer, and A release film was proposed in which the surface of the olefin polymer was oxidized (see Patent Document 1).

  According to this method, the adhesion between the olefin polymer and polydimethylsiloxane is good, but the surface of the release film cannot be written with magic ink or the like, and the required writing property for a packaging tape or the like is satisfied. The problem of being unable to do so occurred. Therefore, it has been difficult to use a release film made of the resin composition as a substrate such as a cloth adhesive tape used for packaging.

JP 2004-297398 A

  The present invention has been made in view of the above situation, and is a release film that has excellent releasability and improved writability without requiring a coating step of a silicone compound containing an organic solvent. Is intended to provide.

  As a result of intensive studies to solve the above problems, the present inventors have obtained a release film obtained by contacting a release film surface made of an olefin polymer and polydimethylsiloxane with a specific rubber for a predetermined time or more. The present inventors have found that the writing property is excellent and have completed the present invention.

  That is, the present invention relates to a surface of a release film composed of a release resin composition composed of 93 to 99.99% by weight of an olefin polymer and 0.01 to 7% by weight of polydimethylsiloxane, an acrylic rubber, The present invention relates to a release film obtained by contacting with at least one rubber selected from natural rubber, polyisoprene rubber, styrene rubber, and butyl rubber for 240 hours or more.

  In the present invention, the releasable resin composition is contained in the molecule with respect to 100 parts by weight of a composition comprising 93 to 99.99% by weight of an olefin polymer and 0.01 to 7% by weight of polydimethylsiloxane. The present invention relates to a release film comprising 0.001 to 1 part by weight of a curing catalyst containing tin and / or titanium.

  The present invention also relates to a release film, wherein the release film surface is oxidized by at least one treatment method selected from corona discharge treatment, flame treatment or plasma treatment.

  Furthermore, the present invention relates to a laminate comprising the release film and a substrate.

  The present invention is described in detail below.

  The olefin polymer constituting the present invention is a homopolymer of a C2-C12 α-olefin such as ethylene, propylene, 1-butene or a copolymer with a vinyl compound. For example, low density polyethylene, high density polyethylene, ethylene / 1-butene copolymer, ethylene / 1-hexene copolymer, ethylene / 1-octene copolymer, ethylene-4-methyl-1-pentene copolymer , Ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-acrylic acid ester copolymer, ethylene-based polymer such as ethylene-methacrylic acid ester copolymer, polypropylene , Propylene / ethylene copolymers, propylene polymers such as propylene / 1-butene copolymer, poly 1-butene, poly 1-hexene, poly 4-methyl-1-pentene, and the like. The combination may be used alone or in combination of two or more. Among such olefin polymers, low-density polyethylene, high-density polyethylene, ethylene · 1 because of excellent adhesion to a substrate when subjected to extrusion lamination molding, and excellent film moldability and cost performance. -Butene copolymer, ethylene / 1-hexene copolymer, and ethylene / 1-octene copolymer are particularly preferred.

  Since such an olefin polymer is excellent in film formability and adhesiveness to a base material when subjected to extrusion laminate molding, a melt mass flow rate (hereinafter referred to as MFR) according to JIS K6922-1 (1997). ) Is preferably in the range of 0.1 to 100 g / 10 min.

Moreover, since the olefin polymer which comprises this invention is excellent in mold release property in the range measured by JISK6922-1 (1997) in the range of 880-970 kg / m < ³ >, it is preferable. If the density is too low, the heat resistance of the release film is insufficient in the pressure-sensitive adhesive application step, and the adhesive strength between the pressure-sensitive adhesive and the release film may increase. On the other hand, if the density is too high, the rigidity of the film may become too high.

  The polydimethylsiloxane constituting the present invention is not particularly limited, but is preferably one having a viscosity at 25 ° C. of 50 cSt or more from the viewpoint of extrusion moldability.

  The polydimethylsiloxane used in the present invention may be one in which some side chains and / or terminal methyl groups are substituted with other functional groups. Such functional groups are not particularly limited, such as vinyl group, hydroxyl group, alkoxy group, amino group, epoxy group, polyether group, aralkyl group, carbinol group, mercapto group, carboxyl group, phenyl group, hydrogen, etc. Can be illustrated. Among such polydimethylsiloxanes, R is an alkyl group having 1 to 30 carbon atoms, a phenyl group, a fluoroalkyl group having 3 to 30 carbon atoms, or 6 carbon atoms, represented by the following structural formula (1). One or more functional groups selected from the group consisting of a fatty acid amide group, a methacryl group and an epoxy group of 30 or less are preferred because of excellent mold releasability, and among them, a methyl group, a phenyl group and an epoxy group are most preferred.

（式中、ｍは１０以上の整数、ｎは１以上の整数である。ここでＲは炭素数１以上３０以下のアルキル基、フェニル基、炭素数３以上３０以下のフルオロアルキル基、又は炭素数６以上３０以下の脂肪酸アミド基、メタクリル基及びエポキシ基からなる群より選ばれる一種以上の官能基であり、分子中にランダムに導入されていてもよい。）
炭素数１以上３０以下のアルキル基としてはメチル基、エチル基、プロピル基、ブチル基等、炭素数３以上３０以下のフルオロアルキル基としてはフルオロエチル基、フルオロブチル基等、炭素数６以上３０以下の脂肪酸アミド基としてはステアリン酸アミド基、オレイン酸アミド基、パルミチン酸アミド基、エルカ酸アミド基等が挙げられる。

(In the formula, m is an integer of 10 or more, and n is an integer of 1 or more. Here, R is an alkyl group having 1 to 30 carbon atoms, a phenyl group, a fluoroalkyl group having 3 to 30 carbon atoms, or carbon. These are one or more functional groups selected from the group consisting of a fatty acid amide group, a methacryl group and an epoxy group having a number of 6 or more and 30 or less, and may be randomly introduced into the molecule.
Examples of the alkyl group having 1 to 30 carbon atoms include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the fluoroalkyl group having 3 to 30 carbon atoms include a fluoroethyl group and a fluorobutyl group. Examples of the fatty acid amide group include a stearic acid amide group, an oleic acid amide group, a palmitic acid amide group, and an erucic acid amide group.

  In addition, when R has a structure containing an epoxy group, it is preferable that the epoxy equivalent of polydimethylsiloxane is 500 g / mol or more and 50000 g / mol or less because of excellent release properties.

  As such polydimethylsiloxane, unmodified polydimethylsiloxane having no functional group other than methyl group (sometimes referred to as straight silicone oil), phenyl group-modified polydimethylsiloxane, methacryl-modified polydimethylsiloxane, Examples include fluoro group-modified polydimethylsiloxane, long-chain alkyl group-modified polydimethylsiloxane, higher fatty acid ester-modified polydimethylsiloxane, fatty acid amide-modified polydimethylsiloxane, and epoxy-modified polydimethylsiloxane. These polydimethylsiloxanes may be used alone or in combination of two or more.

  Examples of such polydimethylsiloxane include Shin-Etsu Silicone KF-96, KF-50, KF-54, KF-1001, KF-102 and the like from Shin-Etsu Chemical Co., Ltd., and trade name SH200 from Toray Dow Corning Co., Ltd. Are commercially available.

  The releasable resin composition constituting the present invention comprises an olefin polymer and polydimethylsiloxane, when a curing catalyst containing tin and / or titanium in the molecule is used in combination with the olefin polymer and polydimethylsiloxane. Compared to the two-component composition, the releasability is improved and the amount of expensive polydimethylsiloxane can be reduced, which is preferable. Although its action has not been clarified, it is considered that it has an effect of reacting and crosslinking the functional group formed on polydimethylsiloxane by the oxidation treatment of the film surface.

  Specific examples of the curing catalyst used in the present invention include organic tin compounds such as dibutyltin dilaurate, dibutyltin dimaleate, dioctyltin dilaurate and tin octylate, alkoxytitanium compounds such as tetraisopropoxytitanium and tetrabutoxytitanium, Examples thereof include organic titanium compounds such as titanate compounds such as tetraisopropyl titanate and tetranormal butyl titanate. Of these, butyltin compounds such as dibutyltin dilaurate and dibutyltin dimaleate, and octyltin compounds such as dioctyltin dilaurate and tin octylate are preferred because of their high releasability improving effect. Among them, dioctyltin dilaurate is preferable It is particularly preferable because of its excellent balance with the above.

The compounding in the releasable resin composition constituting the present invention is olefin polymer 93 to 99.99% by weight, polydimethylsiloxane 0.01 to 7% by weight, preferably olefin polymer 95 to 99.99% by weight. %, 0.01 to 5% by weight of polydimethylsiloxane, most preferably 96 to 99.99% by weight of olefin polymer, and 0.01 to 4% by weight of polydimethylsiloxane. When the polydimethylsiloxane is less than 0.01% by weight, it is not preferable because the release property of the release film is inferior. When the polydimethylsiloxane exceeds 7% by weight, uniform extrusion is difficult when subjected to extrusion molding. It becomes.
Further, when the releasable resin composition contains a curing catalyst containing tin and / or titanium in the molecule, tin and / or in the molecule with respect to 100 parts by weight of the composition comprising the olefin polymer and polydimethylsiloxane. Alternatively, a curing catalyst containing titanium is preferably 0.001 to 1 part by weight because the effect of improving releasability is high, and most preferably, a curing catalyst containing tin and / or titanium in the molecule is 0.01 to 0.001. 5 parts by weight.

  Further, in the releasable resin composition constituting the present invention, an antioxidant, a lubricant, a neutralizing agent, an anti-blocking agent, a surfactant, a slip agent, etc. are usually used for an olefin resin as necessary. You may add the additive in the range which does not impair mold release property.

  The releasable resin composition of the present invention can be produced by a commonly used resin mixing apparatus. Examples thereof include a single-screw extruder, a twin-screw extruder, a Banbury mixer, a pressure kneader, a melt kneader such as a rotating roll, a Henschel mixer, a V blender, a ribbon blender, and a tumbler. When using a melt-kneading apparatus, the melting temperature is preferably about the melting point of the olefin polymer to about 350 ° C.

  The release film surface of the present invention is preferably oxidized in order to suppress transfer of the release agent to the adhesive surface of the tape or label. Further, the peeling strength is reduced by the oxidation, and the releasability can be improved.

  Examples of the oxidation treatment method for oxidizing the release film surface include chromic acid treatment, sulfuric acid treatment, air oxidation, ozone treatment, corona discharge treatment, flame treatment, plasma treatment, and the like. In particular, corona discharge treatment, flame treatment, and plasma treatment are particularly preferable for forming them.

Corona discharge treatment is widely used as a continuous treatment technique for plastic film and sheet surfaces, and is performed by passing the film through a corona atmosphere generated by a corona discharge treatment machine. The corona discharge density is preferably 1 to 100 W · min / m ² because of excellent re-tackiness of the pressure-sensitive adhesive.

  The flame treatment is performed by bringing the film surface into contact with a flame generated when natural gas, propane, or the like is burned.

  Plasma treatment is an excited inert gas that is electrically neutral after removing charged particles by electronically exciting a single or mixed gas such as argon, helium, neon, hydrogen, oxygen, and air with a plasma jet. Is sprayed onto the film surface.

  The release film of the present invention can be produced by a known film forming apparatus such as an inflation molding machine or a T die cast molding machine. In addition, a multilayer film with another polymer material can be produced by a coextrusion inflation molding machine, a coextrusion T die cast molding machine, or the like. Other polymer materials include low density polyethylene, high density polyethylene, ethylene / 1-butene copolymer, ethylene / 1-hexene copolymer, ethylene / 1-octene copolymer, ethylene / 4-methyl- 1-pentene copolymer, ethylene / vinyl acetate copolymer, ethylene / acrylic acid copolymer, ethylene / methacrylic acid copolymer, ethylene / acrylic acid ester copolymer, ethylene / methacrylic acid ester copolymer, etc. Olefin such as ethylene polymer, polypropylene, propylene polymer such as propylene / ethylene copolymer, propylene / 1-butene copolymer, poly 1-butene, poly 1-hexene, poly 4-methyl-1-pentene Polymers, Polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamides Ethylene-vinyl acetate copolymer saponification products thereof.

  Moreover, a laminated body can be manufactured by bonding the release film of this invention with another base material. As such a laminated body, the most preferable form is one in which a release film is laminated on at least one side of a substrate via a polyethylene layer.

  Examples of the substrate constituting the laminate of the present invention include a synthetic polymer film or sheet, woven fabric, nonwoven fabric, paper, metal foil and the like. Examples of the synthetic polymer film or sheet include a film or sheet made of a synthetic polymer such as polyester such as polyethylene terephthalate, polyamide, polyvinyl alcohol, saponified ethylene / vinyl acetate copolymer, polycarbonate, polyethylene, or polypropylene. Furthermore, these polymer films or sheets may have a surface deposited with aluminum, alumina, silica or the like, or may have a surface printed with urethane-based ink or the like. Examples of the woven fabric and non-woven fabric include those made of synthetic resin such as polyester, polyethylene, and polypropylene, or those made of natural materials such as sufu. Examples of the paper include craft paper, kulpack paper, high-quality paper, glassine paper, and paperboard. Of these, paper, or a woven or non-woven fabric made of a synthetic resin or a natural material is preferable because it is easy to cut. In addition, an anchor coating agent such as an isocyanate compound, a urethane compound, or a polyethyleneimine compound may be applied to the surface of these base materials.

  Such a laminate can be manufactured using a calendar molding machine, a press molding machine, an extrusion laminating machine or the like. In extrusion lamination molding, the coextrusion lamination method and the tandem lamination method are most preferable from the viewpoint of economy.

  The thickness of the release film of the present invention is not particularly limited as long as the object of the present invention is achieved, and is preferably 1 μm to 5 mm in thickness because of excellent flexibility and small problems such as breakage. From the viewpoint of economy, the range of 1 μm to 100 μm is most preferable.

  The release film of the present invention has improved writability by bringing the surface into contact with at least one rubber selected from the group consisting of acrylic rubber, natural rubber, polyisoprene rubber, styrene rubber and butyl rubber for 240 hours or more. It has been done.

  Such an acrylic rubber is a homopolymer of an acrylic acid alkyl ester monomer or a methacrylic acid alkyl ester monomer, or an acrylic acid alkyl ester monomer and / or a methacrylic acid alkyl ester monomer and another vinyl monomer copolymerizable therewith. It is a copolymer. As the acrylic acid alkyl ester monomer and / or methacrylic acid alkyl ester monomer, an ester of a primary or secondary alcohol having 1 to 12 carbon atoms of an alkyl group and acrylic acid or methacrylic acid is preferably used. Other vinyl monomers copolymerizable with the above acrylate monomers and / or alkyl methacrylate monomers are acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, maleic anhydride, styrene, acrylonitrile, N-phenyl Examples include maleimide, N-cyclohexylmaleimide, N-vinylpyrrolidone, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, n-methylol acrylamide, glycidyl acrylate, and allyl glycidyl ether.

  Such a polymer of an acrylic acid alkyl ester monomer and / or a methacrylic acid alkyl ester monomer, and / or a copolymer of these with another vinyl monomer may be crosslinked with a peroxide, an isocyanate or the like.

  Examples of such acrylic rubbers include the product name Acryset manufactured by Nippon Shokubai Co., Ltd., and the product name Coponil manufactured by Nippon Synthetic Chemical Co., Ltd., and are also commercially available from Toagosei Co., Ltd. Has been.

  The natural rubber may be unvulcanized or vulcanized.

  Polyisoprene rubber is commercially available from JSR Co., Ltd. and may be unvulcanized or vulcanized.

  Examples of the styrene rubber include styrene-butadiene random copolymer rubber, styrene-isoprene random copolymer rubber, styrene-butadiene block copolymer rubber, and styrene-isoprene block copolymer rubber. Commercially available from JSR Corporation.

  Butyl rubber is excellent in heat resistance, ozone resistance, aging resistance, and electrical insulation. Specific examples include non-vulcanized butyl rubber, vulcanized butyl rubber, and halogenated butyl rubber, and are commercially available from JSR Corporation. ing.

  These rubbers are preferably blended with a tackifier or the like because the effect of improving the writing property is enhanced.

  The shape of such rubber is not particularly limited, and examples thereof include a film shape or a material coated on a substrate. As the rubber coated on the substrate, a product name polyester tape No. 1 manufactured by Nitto Denko Corporation as an acrylic rubber was used. 31B and the like are exemplified, and examples of the styrene-based rubber include a brand name cloth tape 102N manufactured by Nichiban Co., Ltd.

  The contact time between the release film surface of the present invention and the rubber is 240 hours or more. A contact time of less than 240 hours is not preferred because the effect of improving the writing property is low.

  The method of contacting the release film surface with the rubber is not particularly limited, but a method of winding the molten rubber on the release film surface and winding it, after winding the release film surface and the film-like rubber, A method of winding, a method of winding after laminating the surface of the release film and the surface of the rubber coated on the substrate, and a method of winding after winding the rubber on the substrate surface of the laminate composed of the substrate and the release film. Examples thereof include a method of bringing the mold film surface into contact with the rubber surface. After contact, the rubber is peeled from the film.

  The contact temperature between the surface of the release film of the present invention and the rubber is not particularly limited, but it is preferably in the range of 0 ° C. to 60 ° C. without change in releasability.

  The contact time between the release film surface of the present invention and the rubber is 240 hours or more. A contact time of less than 240 hours is not preferred because the effect of improving the writing property is low.

  A release film using the resin composition for a release film of the present invention is extremely useful as a release layer for a packaging tape or the like that requires writing properties on the surface of the release film.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.

  The measurement methods and evaluation methods for physical properties and workability are shown below.

(1) Melt mass flow rate (MFR)
It measured based on JISK6922-1 (1997).

(2) Density The density was measured in accordance with JIS K6922-1 (1997).

(3) Release property A 50 mm wide and 150 mm long Kraft adhesive tape (trade name No. 313, manufactured by Nichiban Co., Ltd.) was applied to the surface of the release film side of the laminate obtained in the example, and the linear pressure was 5 kg. After passing between the rubber rolls at a speed of 5 cm / min / cm, the sample was allowed to stand in an atmosphere of 40 ° C. for 20 hours to obtain a sample for measuring releasability. Thereafter, the peel strength between the craft adhesive tape and the release film was measured with a tensile tester (manufactured by Shimadzu Corporation, trade name: Autograph DCS-100). The peeling speed is 500 mm / min.

(4) Re-adhesiveness The 50 mm wide cloth adhesive tape peeled from the surface of the release film by the above-mentioned releasability test was applied to an aluminum plate (trade name A1N30H-H18, manufactured by Toyo Aluminum Co., Ltd., thickness 0.1 mm) at 5 kg / Affixed with a linear pressure of cm. After leaving in an atmosphere of 23 ° C. for 1 day, the adhesive strength between the craft adhesive tape and the aluminum plate was measured with a tensile tester (Autograph DCS-100, manufactured by Shimadzu Corporation). The peeling speed is 300 mm / min. When the pressure-sensitive adhesive surface of the pressure-sensitive adhesive tape is contaminated by the release film, the adhesive strength of the pressure-sensitive adhesive tape is lowered and the performance as the pressure-sensitive adhesive tape is impaired. That is, the higher the adhesive strength, the better the re-tackiness.

(5) Writability After writing the surface of the laminate obtained in the example with an oily magic, the state of the written writing was wiped with a tissue paper and visually judged.
○: Remaining almost, ×: Not remaining at all Example 1
As an olefin polymer, low-density polyethylene (trade name Petrocene 205 manufactured by Tosoh Corp., hereinafter sometimes referred to as LDPE-A) having an MFR of 3 g / 10 min and a density of 924 kg / m ³ is 99% by weight, poly Straight silicone oil (trade name Shin-Etsu Silicone KF-96 manufactured by Shin-Etsu Chemical Co., Ltd., viscosity 10,000 cSt, hereinafter may be referred to as B-1) as dimethylsiloxane is blended so as to be 1% by weight. The mixture was melt-kneaded with an extruder (Toyo Seiki Laboplast Mill) to obtain a release resin composition pellet.

The pellets of LDPE-A (trade name Petrocene 205 manufactured by Tosoh Corporation) are supplied to an extruder of an extrusion laminator having a 90 mmφ screw, extruded from a T die at a temperature of 320 ° C., and 50 W · min / m ² as a substrate. Was laminated on a corona-treated surface of high-quality paper (trade name Kinmari SW, basis weight 50 g / m ^2, manufactured by Hokuetsu Paper Co., Ltd.) subjected to corona treatment under the conditions described above.

Further, the releasable resin composition obtained by the above method was supplied to an extruder of an extrusion laminator having a 90 mmφ screw, an extrusion release film was formed from a T die at a temperature of 320 ° C., and 20 μm was formed on the LDPE layer. Then, the release film surface was subjected to corona treatment under the condition of 15 W · min / m ² .

  Styrenic rubber (product name No. 313, manufactured by Nichiban Co., Ltd.) applied to the substrate was affixed to the surface of the release film, and the release film surface and the rubber were brought into contact with each other. . Then, the said rubber | gum was peeled and the laminated body containing a release film was obtained.

  The obtained laminate was measured for releasability, re-tackiness, and writing property, and the measurement results are shown in Table 1.

実施例２
離型性樹脂組成物として、ＬＤＰＥ−Ａを９９重量％、ポリジメチルシロキサン（Ｂ−１）を１重量％の代わりに、ＬＤＰＥ−Ａを９９．５重量％、ポリジメチルシロキサン（Ｂ−１）を０．５重量％とした以外は、実施例１と同様にして積層体を得た。評価結果は表１に示した。

Example 2
As the releasable resin composition, LDPE-A was replaced by 99% by weight, polydimethylsiloxane (B-1) by 1% by weight, LDPE-A by 99.5% by weight, polydimethylsiloxane (B-1) A laminate was obtained in the same manner as in Example 1 except that the content was changed to 0.5% by weight. The evaluation results are shown in Table 1.

Example 3
As a releasable resin composition, instead of 99% by weight of LDPE-A and 1% by weight of polydimethylsiloxane (B-1), 99% by weight of LDPE-A and polydimethylsiloxane, an epoxy equivalent of 3,500 g / Mol, epoxy-modified polydimethylsiloxane having a viscosity of 17,000 cSt (trade name Shin-Etsu Silicone KF-1001, manufactured by Shin-Etsu Chemical Co., Ltd., hereinafter sometimes referred to as B-2) is 1% by weight, A laminate was obtained in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 4
As the releasable resin composition, LDPE-A was replaced by 99% by weight, polydimethylsiloxane (B-1) by 1% by weight, LDPE-A by 99.5% by weight, and polydimethylsiloxane (B-2). A laminate was obtained in the same manner as in Example 1 except that the content was changed to 0.5% by weight. The evaluation results are shown in Table 1.

Example 5
As a releasable resin composition, LDPE-A was replaced by 99% by weight, polydimethylsiloxane (B-1) by 1% by weight, LDPE-A by 97% by weight, and polydimethylsiloxane (B-2) by 3%. A laminate was obtained in the same manner as in Example 1 except that the amount was changed to% by weight. The evaluation results are shown in Table 1.

Example 6
As the releasable resin composition, LDPE-A 99% by weight, polydimethylsiloxane (B-1) 1% by weight, LDPE-A 99% by weight, polydimethylsiloxane as methylphenyl silicone oil ( The laminate was manufactured in the same manner as in Example 1 except that Shin-Etsu Chemical Co., Ltd., trade name Shin-Etsu Silicone KF-50, viscosity 3,000 cSt, hereinafter sometimes referred to as B-3) was 1% by weight. Obtained. The evaluation results are shown in Table 2.

実施例７
離型性樹脂組成物として、ＬＤＰＥ−Ａを９９重量％、ポリジメチルシロキサン（Ｂ−１）を１重量％の代わりに、ＬＤＰＥ−Ａを９８．９８重量％、ポリジメチルシロキサン（Ｂ−１）を１重量％、硬化触媒としてジラウリン酸ジオクチル錫を０．０２重量％とした以外は、実施例１と同様にして積層体を得た。評価結果は表２に示した。

Example 7
As a releasable resin composition, LDPE-A was replaced by 99% by weight, polydimethylsiloxane (B-1) by 1% by weight, LDPE-A by 98.98% by weight, polydimethylsiloxane (B-1) A laminate was obtained in the same manner as in Example 1 except that 1% by weight was used and 0.02% by weight of dioctyltin dilaurate was used as a curing catalyst. The evaluation results are shown in Table 2.

Example 8
As the releasable resin composition, instead of 99% by weight of LDPE-A and 1% by weight of polydimethylsiloxane (B-1), MFR is 7.5 g / 10 min and density is 902 kg as an olefin polymer. / M ³ ethylene / 1-octene copolymer (trade name Affinity PT1450 manufactured by Dow Chemical Co., Ltd., sometimes referred to as LLDPE) 99% by weight, polydimethylsiloxane (B-1) 1% by weight Obtained a laminate in the same manner as in Example 1. The evaluation results are shown in Table 2.

Example 9
A laminate was obtained in the same manner as in Example 1 except that acrylic rubber (trade name 31B manufactured by Nitto Denko Corporation) applied to the substrate was used instead of styrene rubber. The evaluation results are shown in Table 2.

Comparative Example 1
A laminate was obtained in the same manner as in Example 1 except that the styrene rubber was not brought into contact with the surface of the release film. Although the evaluation result is shown in Table 3, it was inferior in writing property.

Comparative Example 2
A laminate was obtained in the same manner as in Example 1 except that the contact time between the release film surface and the styrene rubber was 170 hours. Although the evaluation result is shown in Table 3, it was inferior in writing property.

Comparative Example 3
As the releasable resin composition, the same procedure as in Example 1 was conducted except that LDPE-A was changed to 99% by weight, and polydimethylsiloxane (B-1) was changed to 1% by weight, and LDPE-A was changed to 100% by weight. To obtain a laminate. The evaluation results are shown in Table 3, but the peel strength was too high to measure the peel strength, and the release properties were inferior.

Comparative Example 4
As a releasable resin composition, LDPE-A was replaced by 99% by weight, polydimethylsiloxane (B-1) by 1% by weight, LDPE-A by 92% by weight, and polydimethylsiloxane (B-1) by 8%. Except for the weight percent, an attempt was made to produce a laminate in the same manner as in Example 1, but the laminate could not be obtained due to poor extrusion.

Claims (8)

The surface of a release film composed of a release resin composition composed of 93 to 99.99% by weight of an olefin polymer and 0.01 to 7% by weight of polydimethylsiloxane is coated with acrylic rubber, natural rubber or polyisoprene rubber. A release film obtained by contact with at least one rubber selected from the group consisting of styrene rubber and butyl rubber for 240 hours or longer. The releasable resin composition contains tin and / or titanium in the molecule with respect to 100 parts by weight of the composition comprising 93 to 99.99% by weight of the olefin polymer and 0.01 to 7% by weight of polydimethylsiloxane. The release film according to claim 1, wherein the curing catalyst is mixed in an amount of 0.001 to 1 part by weight. The release film according to claim 1 or 2, wherein the polydimethylsiloxane is represented by the following structural formula (1).

(In the formula, m is an integer of 10 or more, and n is an integer of 1 or more. Here, R is an alkyl group having 1 to 30 carbon atoms, a phenyl group, a fluoroalkyl group having 3 to 30 carbon atoms, or carbon. These are one or more functional groups selected from the group consisting of a fatty acid amide group, a methacryl group and an epoxy group having a number of 6 or more and 30 or less, and may be randomly introduced into the molecule. The release film according to claim 1 or 2, wherein the polydimethylsiloxane is a polydimethylsiloxane having an epoxy group having a functional group equivalent of 500 g / mol or more and 50000 g / mol or less. The release film according to any one of claims 1 to 4, wherein the release film surface is oxidized by at least one treatment method selected from corona discharge treatment, flame treatment, and plasma treatment. A laminate comprising the release film according to any one of claims 1 to 5 and a substrate. The laminate according to claim 6, wherein a release film is laminated on at least one surface of the substrate via a polyethylene layer. The laminate according to claim 7, wherein the substrate is at least one selected from paper, a woven fabric or a nonwoven fabric made of natural material or synthetic resin.