JP2021191825A - Polyolefin-based resin film, adhesive film, decorative film, decorative adhesive film - Google Patents

Abstract

To provide a film having excellent appearance according to favorable workability, handleability, heat resistance, and usage.SOLUTION: A polyolefin-based resin film characterized by having, in differential scanning calorimetry, at least one crystal melting peak within the temperature range of 70°C or higher and 170°C or lower, and a crystal melting peak in a temperature range of 200°C or higher, and a tensile modulus of 1400 MPa or smaller, and containing 20 mass% or higher of polymethylpentene-based resin.SELECTED DRAWING: None

Description

The present invention relates to an adhesive film (tape) used in a semiconductor manufacturing process, a cosmetic adhesive film (tape) such as a sticker, a label, a marking film, etc., which is attached to give a design to a signboard, an automobile, or the like. The present invention relates to a polyolefin-based resin film preferably used as a base material such as a sheet, an adhesive film in which an adhesive layer is laminated on the film, a decorative film in which a printing layer is laminated, and the like.

Adhesive films (tapes), signs, cosmetic adhesive films (tapes) such as labels and marking films, decorative sheets, etc. that are conventionally attached to impart design to automobiles, etc. used in the semiconductor manufacturing process. A film made of a polyvinyl chloride resin (hereinafter, also referred to as "PVC-based film") having excellent colorability, processability, scratch resistance, weather resistance and the like has been widely used as a base material.
The PVC-based film has rigidity by itself, but a plasticizer is added for the purpose of imparting flexibility so that it can function as an adhesive film. However, depending on the plasticizer used, there are problems that the compatibility with the pressure-sensitive adhesive is poor, the stability is poor when the pressure-sensitive adhesive film is used, and the bleed-out of the plasticizer becomes remarkable. There is also a tendency for regulations to be tightened on the use of plasticizers themselves.
Therefore, a polyolefin-based resin film has been widely used as a material in place of the PVC-based film.

Decorative films for interior and exterior of buildings using polyolefin resin film as a base material, marking films for interior and exterior of automobiles, etc. are known. Film technology and the like are disclosed.
The general polyolefin-based resins described in these documents, such as polypropylene and polyethylene, do not have a melting point exceeding 200 ° C. and are not suitable as resins that can withstand high temperatures in the vicinity of 200 ° C. It is extremely difficult to form a film using a resin obtained by cross-linking them.

As a polyolefin resin having a melting point of 200 ° C. or higher, there is a polymethylpentene resin, and a technique relating to a film using the resin is already known, and it has been confirmed that the resin is used depending on the application (Patent Document). 3).
Further, there is also a technique of mixing a polymethylpentene-based resin with a general polyolefin-based resin such as polypropylene or polyethylene to form a film (Patent Document 4).

However, since the polymethylpentene-based resin is used alone in the technique described in Patent Document 3, it is presumed that it is difficult to process the polymethylpentene-based resin at a temperature equal to or lower than the melting point.
Further, it is considered that the technique described in Patent Document 4 has a small content of the polymethylpentene resin used and is insufficient for maintaining heat resistance.

Further, as a heat-resistant polyolefin resin, there is also a technique for a polyolefin resin film using a polyamide block graft copolymer graft-bonded with polyamide (Patent Document 5).
However, in the technique described in Patent Document 5, foreign matter and streak-like appearance defects are observed probably because the compatibility between the polyolefin resin and the polyamide block graft copolymer is not sufficient, and the above-mentioned request for appearance control is required. There was room for improvement in the development of such applications.

Therefore, it is considered that there is still room for improvement in providing a film that solves these problems, such as good processability, handleability, heat resistance, and excellent appearance according to the application.

Japanese Unexamined Patent Publication No. 10-36590 Japanese Unexamined Patent Publication No. 11-172017 Japanese Unexamined Patent Publication No. 2012-228828 Japanese Patent No. 5816178 Japanese Patent No. 6535508

The present invention has been made in view of the above-mentioned conventional problems, and by using the polyolefin-based resin film of the present invention, the film has good processability, handleability, heat resistance, and an excellent appearance according to the application. , A film that solves these problems can be obtained. Further, it is also possible to obtain an adhesive film, a decorative film or a cosmetic adhesive film by laminating an adhesive layer or a printing layer on the film, and these films can be used for semiconductor manufacturing processes, automobile interior / exterior and automobile cosmetic applications. Can also be preferably used.

The present inventors have diligently studied a polyolefin-based resin film having excellent processability, handleability, heat resistance, and an excellent appearance according to the application, and found a polyolefin-based resin film capable of achieving both of them. The invention was completed.

That is, the gist of the present invention is as follows.
[1]
In differential scanning calorimetry, it has at least one crystal melting peak in the temperature range of 70 ° C or higher and 170 ° C or lower, further has a crystal melting peak in the temperature range of 200 ° C or higher, and has a tensile elastic modulus of 1400 MPa or lower. And
A polyolefin-based resin film characterized by containing 20% by mass or more of a polymethylpentene-based resin.
[2]
Suggestion The polyolefin-based resin film according to [1], which contains a polyolefin-based resin having a crystal melting peak in the temperature range of 70 ° C. or higher and 150 ° C. or lower in scanning calorific value measurement.
[3]
The polyolefin-based resin contains at least one selected from the group consisting of polypropylene-based resins, polyethylene-based resins, olefin-based elastomers, and styrene-based elastomers, and is characterized by containing a polymethylpentene-based resin [1]. ] Or the polyolefin resin film according to [2].
[4]
The polyolefin-based resin film according to any one of [1] to [3], wherein the content of the polymethylpentene-based resin is 20% by mass or more and 70% by mass or less.
[5]
The item according to any one of [1] to [4], wherein the film exhibits an elongation of 1500 μm in the range of 80 to 165 ° C. when thermomechanical analysis is performed under the following conditions. Polyolefin resin film.
<Conditions>
Specimen size: width 4 mm x length 20 mm
Distance between chucks: 8 mm
Measurement atmosphere: Under nitrogen atmosphere (nitrogen flow rate 100 ml / min)
Temperature rise rate: 5 ° C / min (start temperature: 23 ° C, end temperature: 250 ° C)
Load: 0.3N / mm ²
[6]
An adhesive film obtained by laminating an adhesive layer on at least one surface of the polyolefin-based resin film according to any one of [1] to [5].
[7]
The adhesive film according to [6], which is used as a film for a semiconductor manufacturing process.
[8]
A decorative film obtained by laminating a printing layer on at least one side of the polyolefin-based resin film according to any one of [1] to [5].
[9]
A cosmetic adhesive film obtained by further laminating an adhesive layer on the print layer side of the decorative film according to [8].

By using the polyolefin-based resin film of the present invention, it is possible to obtain a film having excellent processability, handleability, heat resistance, and an excellent appearance according to the application. Further, it is also possible to obtain an adhesive film, a decorative film or a cosmetic adhesive film by laminating an adhesive layer or a printing layer on the film, and these films can be used for semiconductor manufacturing processes, automobile interior / exterior and their cosmetic applications. Can also be suitably used

The present invention will be described in detail below, but the present invention is not limited to the following embodiments, and can be variously modified and carried out within the scope of the gist thereof. In addition, when the expression "~" is used in this specification, it shall be used as an expression including numerical values or physical property values before and after the expression.

The film of the present invention has at least one crystal melting peak in the temperature range of 70 ° C. or higher and 170 ° C. or lower in differential scanning calorimetry, and further has a crystal melting peak in the temperature range of 200 ° C. or higher. A polyolefin-based resin film having a tensile elasticity of 1400 MPa or less and containing 20% by mass or more of a polymethylpentene-based resin.

<Polyolefin resin>
The resin composition used for producing the film of the present invention contains a polyolefin-based resin as an essential component. Polyolefin-based resins are preferably used from the viewpoints of easy availability, flexibility, handleability, economy, and having an appropriate crystal melting peak.

Examples of the polyolefin resin include polyethylene resin, polypropylene resin, olefin elastomer, cyclic olefin resin, polymethylpentene resin and the like.
Among the polyolefin-based resins, polyethylene-based resins, polypropylene-based resins, and olefin-based elastomers are preferable from the viewpoint of easy availability and imparting flexibility to the obtained film.

Examples of the polyethylene-based resin include homopolymers of ethylene, copolymers of ethylene containing ethylene as a main component and other monomers copolymerizable (low density polyethylene (LDPE), high pressure method low density polyethylene, and the like. Linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), ethylene-based copolymer (metallocene-based polyethylene) obtained by polymerization using a metallocene-based catalyst, ethylene-vinyl acetate copolymer, ethylene- (meth). ) Methyl acrylate copolymer, ethylene- (meth) ethyl acrylate copolymer, ethylene- (meth) butyl acrylate copolymer, ethylene- (meth) acrylate copolymer, ethylene- (meth) acrylate copolymer Examples thereof include a metal ion cross-linking resin (ionomer) of a polymer.
Among them, low density polyethylene (LDPE) and linear low density polyethylene (LLDPE) are preferably used from the viewpoint of easy availability, handleability of the resin, and imparting flexibility to the obtained film.

Examples of the polypropylene-based resin include a homopolymer of propylene (homopolypropylene), a copolymer of propylene containing propylene as a main component and another monomer copolymerizable with the copolymer, and a mixture thereof.
Examples of the copolymer of propylene containing propylene as a main component and a copolymerizable other monomer include a random copolymer (random polypropylene) of propylene and ethylene or another α-olefin, or a block copolymer. (Block polypropylene), a block copolymer containing a rubber component, a graft copolymer and the like can be mentioned.
The α-olefin used as the other monomer copolymerizable with propylene preferably has 4 to 12 carbon atoms, and is, for example, 1-butene, 1-pentene, 1-hexene, 1-hexene. , 1-octene, 4-methyl-1-pentene, 1-decene and the like, and one or a mixture of two or more thereof is used.
Among these, from the viewpoint of controlling heat resistance and availability, it is preferable to contain a random copolymer (random polypropylene), and it is more preferable to contain a homopolymer of propylene (homopropylene). ..

The olefin-based elastomer is a soft resin containing a polyolefin-based resin and a rubber component, and the rubber component may be dispersed in the polyolefin-based resin or may be copolymerized with each other.
Specific examples of the olefin-based elastomer include ethylene-propylene copolymer elastomer, ethylene-1-butene copolymer elastomer, ethylene-propylene-1-butene copolymer elastomer, and ethylene-1-hexene copolymer elastomer. , Ethylene-1-octene copolymer elastomer, ethylene-styrene copolymer elastomer, ethylene-norbornen copolymer elastomer, propylene-1-butene copolymer elastomer, ethylene-propylene-non-conjugated diene copolymer elastomer, ethylene Atypical elastic copolymers mainly composed of olefins such as -1-butene-non-conjugated diene copolymer elastomer and ethylene-propylene-1-butene-non-conjugated diene copolymer elastomer, derivatives thereof and acid modification. Derivatives and the like can be mentioned.

The above-mentioned polyethylene-based resin, polypropylene-based resin, olefin-based elastomer and the like may be used alone or in combination of two or more. From the viewpoint of the flexibility of the obtained film and the film-forming property when processing the film, it is preferable to use two or more kinds in combination.

The melt flow rate of the above-mentioned polyethylene-based resin, polypropylene-based resin, olefin-based elastomer, etc. is appropriately selected depending on the molding method and application to which it is applied, but is measured under a temperature condition of 190 ° C. or 230 ° C. under a load of 2.16 kg. The value is preferably 0.1 to 50 g / 10 minutes. If it is 0.5 g / 10 minutes or more, the formability of the film becomes good, and if it is 50 g / 10 minutes or less, the thickness accuracy of the film can be kept good. It is more preferably 0.5 to 40 g / 10 minutes, still more preferably 1.0 to 30 g / 10 minutes.

The crystal melting peak of a polyethylene resin, a polypropylene resin, an olefin elastomer or the like is preferably in the range of 70 ° C. or higher and 170 ° C. or lower as a value measured by differential scanning calorimetry. By having the crystal melting peak in the range of 70 ° C. or higher and 170 ° C. or lower, it is possible to improve the processability of the obtained film at a temperature of 200 ° C. or lower. It is more preferably 72 ° C. or higher and 168 ° C. or lower, and further preferably 75 ° C. or higher and 165 ° C. or lower. Further, by using a material having a crystal melting peak in the range of 70 ° C. or higher and 150 ° C. or lower, it is possible to further improve the processability of the film at a temperature of 200 ° C. or lower.
Here, as a condition for measuring the differential scanning calorimetry, the temperature is usually raised from 25 ° C. to 250 ° C. at a heating rate of 10 ° C./min, then lowered to 25 ° C. at a cooling rate of 10 ° C./min, and then raised again. The temperature is raised to 250 ° C. at a speed of 10 ° C./min.

Regarding the strength of polyethylene-based resins, polypropylene-based resins, olefin-based elastomers, etc., it is preferable that the tensile elastic modulus of the film obtained by these resins alone is in the range of 100 to 2000 MPa. When the tensile elastic modulus is in the range of 100 to 2000 MPa, it is possible to impart appropriate flexibility to the film of the present invention. It is more preferably in the range of 150 to 1900 MPa, still more preferably in the range of 200 to 1800 MPa.

The content of the polyethylene-based resin, polypropylene-based resin, olefin-based elastomer and the like is preferably 30% by mass or more and 90% by mass or less. When the content is 30% by mass or more, processability and flexibility can be imparted to the obtained film, and when the content is 90% by mass or less, deterioration of heat resistance can be suppressed. It is more preferably 35% by mass or more and 85% by mass or less, and further preferably 40% by mass or more and 80% by mass or less.

It is preferable to add a polymethylpentene resin to the polyolefin resin film of the present invention for the purpose of imparting a crystal melting peak of 200 ° C. or higher. The polymethylpentene-based resin means a homopolymer having methylpentene as a monomer or a copolymer with other monomers. Specific examples include a copolymer of 4-methylpentene-1 and an α-olefin exemplified as another monomer copolymerizable with propylene.

When the polymethylpentene-based resin is a copolymer, the content of the α-olefin component used for the copolymerization is preferably 20% by mass or less. By setting the content to 20% by mass or less, it is possible to suppress a decrease in the crystal melting peak. More preferably, it is 10% by mass or less.

The melt flow rate of the polymethylpentene resin is appropriately selected depending on the molding method and application to which it is applied, but the value measured under a temperature condition of 260 ° C. under a load of 5.0 kg is 0.1 to 50 g / 10 minutes. It is preferable to have. If it is 0.5 g / 10 minutes or more, the formability of the film becomes good, and if it is 50 g / 10 minutes or less, the thickness accuracy of the film can be kept good. It is more preferably 0.5 to 40 g / 10 minutes, still more preferably 1.0 to 35 g / 10 minutes.

The crystal melting peak of the polymethylpentene resin preferably shows 210 ° C. or higher as a value measured by differential scanning calorimetry. Having a crystal melting peak of 210 ° C. or higher makes it possible to sufficiently impart heat resistance to the obtained film. It is more preferably 210 ° C. or higher, and even more preferably 220 ° C. or higher.
Here, as the conditions for measuring the differential scanning calorimetry, the same method as described above can be used.

Regarding the strength of the polymethylpentene-based resin, it is preferable that the tensile elastic modulus of the film obtained by the resin alone is in the range of 100 to 2000 MPa. When the tensile elastic modulus is in the range of 100 to 2000 MPa, it is possible to impart appropriate flexibility to the film of the present invention. It is more preferably in the range of 150 to 1900 MPa, still more preferably in the range of 200 to 1800 MPa.

The content of the polymethylpentene resin is preferably 20% by mass or more and 70% by mass or less. When the content is 20% by mass or more, it is possible to impart sufficient heat resistance to the obtained film. By setting the content to 70% by mass or less, it is possible to improve the processability of the obtained film at 200 ° C. or lower. It is more preferably 25% by mass or more and 65% by mass or less, and further preferably 30% by mass or more and 60% by mass or less.

To the resin composition used for the polyolefin-based resin film of the present invention, a styrene-based elastomer, a cyclic olefin-based resin, or the like is added as a resin other than the above-mentioned polyethylene-based resin, polypropylene-based resin, and olefin-based elastomer, if necessary. You can also do it.

The styrene-based elastomer is preferably a block copolymer represented by the following formula (I) or (II).
X- (Y-X) n ... (I)
(XY) n ... (II)
X in the general formulas (I) and (II) is an aromatic vinyl polymer block typified by styrene, and in the formula (I), the degree of polymerization may be the same or different at both ends of the molecular chain. May be good. In addition, Y is a butadiene polymer block, an isoprene polymer block, a butadiene / isoprene copolymer block, a hydrogenated butadiene polymer block, a hydrogenated isoprene polymer block, and a hydrogenated butadiene / isoprene co-weight. At least one selected from coalesced blocks, partially hydrogenated butadiene polymer blocks, partially hydrogenated isoprene polymer blocks and partially hydrogenated butadiene / isoprene copolymer blocks. Further, n is an integer of 1 or more.

Examples of the cyclic olefin-based resin include norbornene-based polymers, vinyl alicyclic hydrocarbon polymers, and cyclic conjugated diene polymers. Among these, norbornene-based polymers are preferable. Examples of the norbornene-based polymer include a ring-opening polymer of a norbornene-based monomer, a norbornene-based copolymer obtained by copolymerizing a norbornene-based monomer and an α-olefin such as ethylene. Moreover, these hydrogenated additives can also be used.

<Other ingredients>
In addition to the above-mentioned polyolefin-based resin and polymethylpentene-based resin, various additives can be added to the resin composition used for the polyolefin-based resin film of the present invention in order to impart heat resistance, weather resistance, and the like.
Specific examples include, for example, antistatic agents, antioxidants, neutralizers, lubricants, antiblocking agents, plasticizers, heat stabilizers, light stabilizers, dyes and pigments, crystal nucleating agents, ultraviolet absorbers, fillers, etc. Inorganic fillers that impart rigidity, elastomers other than those described above for imparting flexibility, and the like may be used as long as the effects of the present invention are not impaired.

As the ultraviolet absorber, known ones can be used, and examples thereof include a benzotriazole-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, and a triazine-based ultraviolet absorber.
As the light stabilizer, known ones can be used, and examples thereof include hindered amine-based light stabilizers.
As the antistatic agent, known ones can be used, but a polymer type antistatic agent may be used in order to impart long-term antistatic properties to the film and suppress defects caused by bleeding out to the surface. preferable. As a specific example of the polymer antistatic agent, known ones can be used, for example, a block copolymer of a hydrophobic block and a hydrophilic block can be used, and a hydrophobic block and a hydrophilic block can be used. However, examples thereof include those in which a block copolymer is formed by an ester bond, an ether bond, an amide bond, an imide bond, a urethane bond, a urea bond, or the like.
As a lubricant or anti-blocking agent, it has excellent compatibility with the above-mentioned polyolefin resin, and it enables defects due to bleed-out to the surface of the obtained film and long-term scratch resistance and slipperiness. It is preferable to use a silicone-olefin copolymer.

<Polyolefin resin film>
The polyolefin-based resin film of the present invention refers to a single-layer or multi-layer film obtained by molding the above-mentioned resin composition.
By using a multi-layer film instead of a single layer, it is possible to unevenly distribute various additives such as the above-mentioned silicone-olefin copolymer only on the outermost layer, which improves the performance of the film and is economical. It is also effective from.
The polyolefin-based resin film of the present invention has at least one crystal melting peak in the temperature range of 70 ° C. or higher and 170 ° C. or lower in differential scanning calorimetry, and further has a crystal melting peak in the temperature range of 200 ° C. or higher. Is required. Having a crystal melting peak in the range of 70 ° C. or higher and 170 ° C. or lower makes it possible to improve processability at a temperature of 200 ° C. or lower. It is more preferably 70 ° C. or higher and 160 ° C. or lower, and further preferably 70 ° C. or higher and 150 ° C. or lower.
Here, as the conditions for measuring the differential scanning calorimetry, the same method as described above can be used.

The film of the present invention was measured in accordance with JIS K 7161 using a test piece (JIS K 6732) collected from the film at a tensile speed of 50 mm / min in an atmosphere of 23 ° C. and 50% RH with a tensile tester. It is required that the tensile elastic modulus is 1400 MPa or less. By setting the pressure to 1400 MPa or less, the processability when laminating the adhesive layer or the printing layer on the polyolefin resin film of the present invention and the polyolefin resin film of the present invention having the adhesive layer have a three-dimensional shape such as an automobile exterior. It is possible to maintain good handleability when attaching to an article. It is more preferably 1350 MPa or less, still more preferably 1300 MPa or less. The tensile elastic modulus of the obtained polyolefin-based resin film can be adjusted by adjusting the type and amount of the polyolefin-based resin or the like described above.

As a film forming method, a known method can be used, but it is preferable to use a melt extrusion molding method. Among the melt extrusion molding methods, the T-die molding method in which a resin in a molten state is extruded from an extruder having a T-die and cooled and solidified to obtain a film is more preferable.
In order to obtain a film, it is preferable to use a coextrusion T-die molding method using a plurality of extruders. A multi-layer film can be obtained by using a coextrusion T-die molding method using a plurality of extruders, and a single-layer film can be obtained by extruding the same resin from all the extruders. It is also possible.
As a coextrusion T-die molding method, a method of forming a plurality of resin layers into a film by using a multi-manifold die and then contacting the resin layers in the T-die to obtain a film, and a molten state called a feed block. A method of obtaining a multi-layer film after merging and adhering a plurality of resins using a device for merging the resins of the above can be mentioned.

If necessary, the film may be surface-treated on one or both sides by a method such as plasma treatment, corona treatment, ozone treatment, and flame treatment. Depending on the application of the obtained film, it is possible to select whether to perform surface treatment on one side or both sides.

The thickness of the film is not particularly limited, but is preferably 30 to 400 μm. Within the above range, the handleability of the film and the subsequent processability can be well maintained. It is more preferably 50 to 350 μm, still more preferably 70 to 300 μm.

Further, in the case of a multi-layer film, it is preferable that the thickness of the outer layer is within the range of 5 to 40% of the total thickness. When it is 5% or more, it is possible to fully express the performance of the additive when various additives are added only to the outer layer, and when it is 40% or less, it is possible to form a film when obtaining a multi-layer film. It is preferable because it is possible to maintain good sex and economic efficiency. It is more preferably in the range of 5 to 35%, still more preferably in the range of 5 to 30%.

As the breaking elongation of the film, a test piece (JIS K 6732) collected from the film was used according to JIS K 7161, and the tensile speed was 300 mm / min in a tensile tester at 23 ° C. and 50% RH. It is preferable that the tensile elongation at break at the time of measurement is 150% or more. If the tensile elongation at break is 150% or more, defects due to film breakage when the film is taken up during melt extrusion molding, and similar defects in the subsequent step of laminating the printing layer and the adhesive layer should be suppressed. It is preferable because it can be used. It is more preferably 250% or more, still more preferably 350% or more.

When the film of the present invention is subjected to thermomechanical analysis under the following conditions, it is preferable that the film exhibits an elongation of 1500 μm in the range of 80 to 160 ° C.

<Conditions>
Specimen size: width 4 mm x length 20 mm
Distance between chucks: 8 mm
Measurement atmosphere: Under nitrogen atmosphere (nitrogen flow rate 100 ml / min)
Temperature rise rate: 5 ° C / min (start temperature: 23 ° C, end temperature: 250 ° C)
Load: 0.3N / mm ²

By exhibiting an elongation of 1500 μm in the range of 80 to 160 ° C., when the film is used as an adhesive tape, the followability to the adherend in the step of heating the tape and adhering it to the adherend is improved. It becomes possible. It is more preferably in the range of 90 to 160 ° C, and even more preferably in the range of 100 to 160 ° C.

Further, the storage elastic modulus at 190 ° C. of the film of the present invention, is preferably 1.0 × ¹⁰ 5 Pa or more. By storage modulus shows a more 1.0 × 10 5 ^Pa, at the time of the film and the adhesive tape, a film in the step of heating the tape stuck to an adherend that can hold the shape without partitioning molten Therefore, it is possible to maintain good handleability and process passability. It is more preferably 2.0 × 10 ⁵ Pa or more, and further preferably 3.0 × 10 ⁵ Pa or more.

<Adhesive film>
The polyolefin-based resin film of the present invention can be made into an adhesive film by laminating an adhesive layer on at least one surface (hereinafter, also referred to as "adhesive film of the present invention").
The pressure-sensitive adhesive used as the pressure-sensitive adhesive layer is not particularly limited, and for example, various pressure-sensitive adhesives such as natural rubber-based resin, acrylic-based resin, styrene-based resin, silicon-based resin, and polyvinyl ether-based resin are used. Further, a functional layer such as an adhesive layer or a thermosetting resin layer may be further provided on the pressure-sensitive adhesive layer.

In the pressure-sensitive adhesive film of the present invention, one or both sides of the film before laminating the pressure-sensitive adhesive layer may be subjected to the above-mentioned surface treatment. Further, a primer layer may be provided between the base film, which is the polyolefin resin film of the present invention, and the adhesive layer, if necessary.
The thickness of the adhesive layer and the primer layer can be appropriately determined as needed.

<Cosmetic film>
The polyolefin-based resin film of the present invention can be formed into a decorative film by laminating a printing layer on at least one side thereof (hereinafter, also referred to as "decorative film of the present invention").
The print layer constituting the decorative film can be formed by a known method. For example, a known printing method such as an offset printing method, a gravure rotary printing method, and a screen printing method, a known coating method such as a roll coating method and a spray coating method, a flexographic printing method, and the like can be mentioned. Further, a thin-film deposition method can also be used.
Examples of the printed pattern include a pattern consisting of wood grain, stone grain, cloth grain, sand grain, geometric pattern, characters, solid surface, metallic, and the like.
The thickness of the print layer can be appropriately determined as needed.
In the decorative film of the present invention, the above-mentioned surface treatment may be applied to one or both sides of the film before laminating the print layer. Further, a primer layer may be provided between the base film and the printing layer, if necessary.
The thickness of the print layer and the primer layer can be appropriately determined as needed.

<Adhesive film for cosmetics>
The decorative film of the present invention can be made into a cosmetic adhesive film by further laminating an adhesive layer on the printed layer, if necessary.
By attaching the cosmetic adhesive film to the adherend, it is possible to give a beautiful appearance to the adherend, and it is possible to give a beautiful appearance to the adherend, and it is used for cosmetics for interior and exterior of automobiles, other molded bodies and laminates, and applications for interior and exterior of buildings. It can be used for such purposes.

The polyolefin-based resin film of the present invention has good processability, handleability, heat resistance, and an excellent appearance according to the application. Further, it is also possible to obtain an adhesive film or a decorative film by laminating an adhesive layer or a printing layer on the film, and these films can be suitably used for automobile cosmetic applications.

Hereinafter, examples and comparative examples of the present invention will be shown and specifically described, but the present invention is not limited to these examples. The materials used in the following examples and comparative examples, the method for measuring the evaluated characteristics, and the like are as follows.

[Material used]
<Polyolefin resin>
Polymethylpentene (A):
Mitsui Chemicals, Inc .: "RT18" (polymethylpentene resin, melt flow rate at 260 ° C., 5.0 kg: 26 g / 10 minutes, melting point: 232 ° C., tensile elastic modulus of a single film: 1640 MPa)
Polymethylpentene (B):
Mitsui Chemicals, Inc .: "MX002" (polymethylpentene resin, melt flow rate at 260 ° C., 5.0 kg: 21 g / 10 minutes, melting point: 224 ° C., tensile elastic modulus of a single film: 1110 MPa)
Random polypropylene:
"FW4B" manufactured by Japan Polypropylene Corporation (random polypropylene, 230 ° C., melt flow rate at 2.16 kg: 8.0 g / 10 minutes, melting point: 136 ° C., tensile elastic modulus of a single film: 600 MPa)
Homopolypropylene:
"FY6HA" manufactured by Japan Polypropylene Corporation (homopolypropylene, melt flow rate at 230 ° C., 2.16 kg: 2.4 g / 10 minutes, melting point: 169 ° C., tensile modulus of elasticity of a single film: 900 MPa)
Olefin elastomer:
"Toughmer BL3450M" manufactured by Mitsui Chemicals, Inc. (olefin elastomer, melt flow rate at 230 ° C., 2.16 kg: 9.0 g / 10 minutes, melting point: 80 ° C., tensile elastic modulus of a single film: 250 MPa)
Polyamide block graft copolymer:
Arkema LP21H (polyamide block graft copolymer, melt flow rate at 230 ° C., 2.16 kg: 10 g / 10 min, melting point: 216 ° C., tensile modulus of single film: 180 MPa)

<Preparation of resin composition>
Using the above-mentioned polyolefin resin, the blending amount of each layer was 100% by mass in total based on the description in Table 1, and they were dry-blended and mixed. After visually confirming that the mixture was uniformly mixed, a resin composition for film molding was prepared.

<Method of forming a multi-layer film>
For each hopper of three Toshiba Machine single-screw extruders (for outer layer: 35φmm, L / D = 25mm, for intermediate layer: 50φmm, L / D = 32, for outer layer: 35φmm, L / D = 25mm) The dry-blended raw material is put in, the extruder temperature for each of the outer layer and the intermediate layer is set to 210 to 265 ° C., and the three layers of the outer layer / intermediate layer / outer layer are merged at the feed block portion to have a width of 650 mm. Extruded from a T-die (temperature setting 265 ° C. lip opening 0.5 mm). As for the thickness configuration, each extruder rotation speed was set so as to be 10 μm / 80 μm / 10 μm.
The extruded molten resin is cooled and solidified by a winder equipped with a mirror-shaped cooling roll (cooling roll 700 mm width x φ350 mm, roll temperature of about 30 ° C.), and then corona-treated on both sides to perform winding. A film composed of substantially a single resin layer having a thickness of about 100 μm and having three layers of one type was obtained.

[Appearance of film]
The appearance of the obtained film was visually evaluated using the following criteria.
◎: No foreign matter or streaks are found 〇: Foreign matter or streaks are slightly found △: Foreign matter or streaks are found ×: Foreign matter or streaks are noticeably confirmed and cannot be used

[Tension modulus]
A No. 1 dumbbell test piece was collected from the obtained multi-layer film, and a tensile elastic modulus was obtained at a tensile modulus of 50 mm / min using an autograph (AGS-X manufactured by Shimadzu Corporation) at 23 ° C. and an atmosphere of 50% RH. (MPa) was measured.
The tensile elastic modulus was measured in the extrusion direction (MD) of the film.

[Tension breaking elongation]
A No. 1 dumbbell test piece was collected from the obtained film, and stretched at a tensile speed of 300 mm / min using a small tabletop tester (EZ-L manufactured by Shimadzu Corporation) in an atmosphere of 23 ° C. and 50% RH. The degree (%) was measured.
The tensile elongation at break was measured in the extrusion direction (MD) of the film.

[Crystal melting peak]
Using a differential scanning calorimetry device (DSC823e manufactured by METTLER TOLEDO), about 5 mg of the film obtained in each example was heated from 25 ° C. to 250 ° C. at a heating rate of 10 ° C./min, and then cooled. The crystal melting peak was calculated from the chart measured when the temperature was lowered to 25 ° C. at 10 ° C./min and the temperature was raised to 250 ° C. at a heating rate of 10 ° C./min again.

[Temperature at extension of 1500 μm]
The temperature of the 100 μm film at the time of extension of 1500 μm was measured using the following measuring devices and conditions.

<Measurement conditions>
Equipment: Thermomechanical analyzer TMA7100 (manufactured by Hitachi High-Tech Science Corporation)
Specimen size: width 4 mm x length 20 mm
Distance between chucks: 8 mm
Measurement atmosphere: Under nitrogen atmosphere (nitrogen flow rate 100 ml / min)
Temperature rise rate: 5 ° C / min (start temperature: 23 ° C, end temperature: 250 ° C)
Load: 0.3N / mm ²

[Example 1]
Polymethylpentene (A), random polypropylene and homopolypropylene were used as the polyolefin resins used for the outer layer and the intermediate layer, and a film consisting of three layers of one type was obtained. The blending amounts of various polyolefin resins are as shown in Table 1.
No foreign matter or streak-like defects were observed in this film, and the film had an excellent appearance. It was confirmed that the tensile elastic modulus was 1270 MPa and the tensile elongation at break was 520%, and that the product had sufficient flexibility and fracture characteristics.
Further, this film showed two crystal melting peaks of 132 ° C. and 160 ° C. in the range of 70 to 170 ° C., and a crystal melting peak of 232 ° C. in the range of 200 ° C. or higher. The temperature of this film when stretched by 1500 μm was 151 ° C.
As shown above, good processability and heat resistance are observed because the desired crystal melting peak is observed in the range of 70 to 170 ° C. and 200 ° C. or higher, and sufficient film elongation is observed in the range of 80 to 160 ° C. And a film with appearance was obtained.

[Example 2]
The procedure was the same as in Example 1 except that an olefin-based elastomer was used instead of random polypropylene.
No foreign matter or streak-like defects were observed in this film, and the film had an excellent appearance. It was confirmed that the tensile elastic modulus was 500 MPa and the tensile elongation at break was 520%, and that the product had sufficient flexibility and fracture characteristics.
Further, this film showed two crystal melting peaks of 80 ° C. and 160 ° C. in the range of 70 to 170 ° C., and a crystal melting peak of 232 ° C. in the range of 200 ° C. or higher. The temperature of this film when stretched by 1500 μm was 149 ° C.
As shown above, good processability and heat resistance are observed because the desired crystal melting peak is observed in the range of 70 to 170 ° C. and 200 ° C. or higher, and sufficient film elongation is observed in the range of 80 to 160 ° C. And a film with appearance was obtained.

[Example 3]
The procedure was the same as in Example 1 except that polymethylpentene (A), random polypropylene and homopolypropylene were changed to the formulations shown in Table 1.
Although foreign matter and streaky defects were slightly observed in this film, the film had a good appearance. It was confirmed that the tensile elastic modulus was 1240 MPa and the tensile elongation at break was 370%, and that the product had sufficient flexibility and fracture characteristics.
Further, this film showed two crystal melting peaks of 132 ° C. and 160 ° C. in the range of 70 to 170 ° C., and a crystal melting peak of 232 ° C. in the range of 200 ° C. or higher. The temperature of this film when stretched by 1500 μm was 163 ° C.
As shown above, although it has a desired crystal melting peak in the range of 70 to 170 ° C and above 200 ° C, the elongation temperature of 1500 μm deviates slightly from the range of 80 to 160 ° C, so that the appearance is good. Although the film was slightly inferior in processability.

[Example 4]
The procedure was the same as in Example 1 except that polymethylpentene (B) was used instead of polymethylpentene (A).
No foreign matter or streak-like defects were observed in this film, and the film had a good appearance. It was confirmed that the tensile elastic modulus was 1050 MPa and the tensile elongation at break was 520%, and that it had sufficient flexibility and fracture characteristics.
Further, this film showed two crystal melting peaks of 132 ° C. and 160 ° C. in the range of 70 to 170 ° C., and a crystal melting peak of 224 ° C. in the range of 200 ° C. or higher. The temperature of this film when stretched by 1500 μm was 145 ° C.
As shown above, good processability and heat resistance are observed because the desired crystal melting peak is observed in the range of 70 to 170 ° C. and 200 ° C. or higher, and sufficient film elongation is observed in the range of 80 to 160 ° C. And a film with appearance was obtained.

[Comparative Example 1]
A film was obtained by the same method as in Example 1 except that only polymethylpentene (A) was used as the polyolefin resin.
No foreign matter or streak-like defects were observed in this film, and the film had an excellent appearance. However, the tensile elastic modulus was 1640 MPa, the tensile elongation at break was 330%, and the film had a high tensile elastic modulus.
Furthermore, this film did not have a crystal melting peak in the range of 70 to 170 ° C, but showed only a crystal melting peak of 232 ° C in the range of 200 ° C or higher. The temperature of this film when stretched by 1500 μm was 176 ° C.
As shown above, the tensile modulus is high, no crystal melting peak is shown in the range of 70 to 170 ° C, and sufficient film elongation is not seen in the range of 80 to 160 ° C. Was a film that was excellent but significantly inferior in processability.

[Comparative Example 2]
Polymethylpentene (A) and homopolypropylene were blended in the amounts shown in Table 1, and a film was obtained by the same method as in Example 1.
Foreign matter and streak-like defects were observed in this film, and the film was inferior in appearance. Further, the tensile elastic modulus was 1430 MPa and the tensile elongation at break was 340%, and the film had a high tensile elastic modulus.
This film had a crystal melting peak in the range of 70 to 170 ° C. and a crystal melting peak of 232 ° C. in the range of 200 ° C. or higher. However, the temperature of this film when stretched to 1500 μm was 196 ° C.
As shown above, as shown above, although it has a desired crystal melting peak in the range of 70 to 170 ° C and above 200 ° C, sufficient film elongation is not seen in the range of 80 to 160 ° C. The film was inferior in appearance and remarkably inferior in processability.

[Comparative Example 3]
A film was obtained by the same method as in Example 1 except that only polymethylpentene (B) was used as the polyolefin resin.
No foreign matter or streak-like defects were found in this film, and the film had an excellent appearance. It was confirmed that the tensile elastic modulus was 1110 MPa and the tensile elongation at break was 340%, and that the product had sufficient flexibility and fracture characteristics.
However, this film did not have a crystal melting peak in the range of 70 to 170 ° C, but showed only a crystal melting peak of 224 ° C in the range of 200 ° C or higher. The temperature of this film when stretched by 1500 μm was 178 ° C.
As shown above, although the tensile modulus at room temperature is a desired value, it does not show a crystal melting peak in the range of 70 to 170 ° C, and sufficient film elongation is seen in the range of 80 to 160 ° C. I couldn't. Therefore, the film is excellent in appearance but significantly inferior in processability.

[Comparative Example 4]
The same procedure as in Example 1 was carried out except that random polypropylene and a polyamide block graft copolymer were used as the polyolefin resin in the blending amounts as shown in Table 1.
It is presumed that the compatibility between the random polypropylene and the polyamide block graft copolymer was not sufficient, and foreign matter and streak-like defects were noticeably observed in this film, so that the film was significantly inferior in appearance.

[Example 5]
An acrylic pressure-sensitive adhesive (SK Dyne 1502C manufactured by Soken Kagaku Co., Ltd.) was applied to the surface of the film obtained in Example 1 on the cooling roll side by a comma-coating method to increase the thickness of the pressure-sensitive adhesive layer after drying. After coating to 25 μm and drying in a hot air dryer at 80 ° C. for 5 minutes, an adhesive layer is formed, and an adhesive layer is formed on the surface of this multi-layer film that does not contain a silicone-olefin copolymer. Adhesive film was obtained by laminating.

[Example 6]
The ink manufactured by DIC Graphics Co., Ltd. described below is applied to the surface of the film obtained in Example 1 on the cooling roll side, manufactured by Kurashiki Spinning Co., Ltd., a gravure printing tester "GP-2", and a printing plate ". The film was coated using "54L6 gradation". The coated film was aged at 40 ° C. for 5 days to obtain a decorative film on which a printing layer with ink was laminated.
<Ink manufactured by DIC Graphics Co., Ltd.>
95% by mass of "VTP-NT40 yellow (A)" and 5% by mass of "AT-NT solvent"
Was mixed and stirred to prepare an ink.
"VTP-NT40 Yellow (A)": Paint consisting of a mixture of vinyl chloride / vinyl acetate copolymer and acrylic resin and methyl isobutyl ketone as a solvent "AT-NT solvent": Mixture of butyl acetate / ethyl acetate / methyl ethyl ketone

[Example 7]
Acrylic adhesive (SK Dyne 1502C manufactured by Soken Kagaku Co., Ltd.) is applied on the separator by the comma coating method so that the thickness of the adhesive layer after drying is 25 μm, and it is put into a hot air dryer at 80 ° C. After drying for 5 minutes, a pressure-sensitive adhesive layer was formed, and the pressure-sensitive adhesive layer was bonded to the surface of the cosmetic film obtained in Example 6 on the print layer side to obtain a cosmetic pressure-sensitive adhesive film.

When the adhesive film obtained in Example 5 and the cosmetic adhesive film obtained in Example 7 were attached to the exterior of an automobile, the film had excellent flexibility and was easily attached to the exterior of the automobile. It was possible to attach it. Therefore, it was confirmed that the adhesive film and the cosmetic adhesive film are excellent in workability and processability.

[Industrial applicability]
By using the polyolefin-based resin film of the present invention, it is possible to obtain a film that solves these problems such as good processability, handleability, heat resistance, and excellent appearance according to the application. Further, it is also possible to obtain an adhesive film or a decorative film by laminating an adhesive layer or a printing layer on the film, and these films can be suitably used for semiconductor processes, automobile interior / exterior and automobile cosmetic applications. can.

Claims (9)

In differential scanning calorimetry, it has at least one crystal melting peak in the temperature range of 70 ° C or higher and 170 ° C or lower, further has a crystal melting peak in the temperature range of 200 ° C or higher, and has a tensile elastic modulus of 1400 MPa or lower. And
A polyolefin-based resin film characterized by containing 20% by mass or more of a polymethylpentene-based resin. Suggestion The polyolefin-based resin film according to claim 1, which comprises a polyolefin-based resin having at least one crystal melting peak in the temperature range of 70 ° C. or higher and 150 ° C. or lower in the scanning calorific value measurement. Claim 1 or 2 which comprises any one or more selected from the group consisting of polypropylene-based resin, polyethylene-based resin, and olefin-based elastomer as the polyolefin-based resin, and also contains polymethylpentene-based resin. The polyolefin-based resin film described in 1. The polyolefin-based resin film according to any one of claims 1 to 3, wherein the content of the polymethylpentene-based resin is 20% by mass or more and 70% by mass or less. The polyolefin system according to any one of claims 1 to 4, wherein the film exhibits an elongation of 1500 μm in the range of 80 to 165 ° C. when thermomechanical analysis is performed under the following conditions. Resin film.
<Conditions>
Specimen size: width 4 mm x length 20 mm
Distance between chucks: 8 mm
Measurement atmosphere: Under nitrogen atmosphere (nitrogen flow rate 100 ml / min)
Temperature rise rate: 5 ° C / min (start temperature: 23 ° C, end temperature: 250 ° C)
Load: 0.3N / mm ² An adhesive film obtained by laminating an adhesive layer on at least one surface of the polyolefin-based resin film according to any one of claims 1 to 5. The adhesive film according to claim 6, which is used as a film for a semiconductor manufacturing process. A decorative film obtained by laminating a printing layer on at least one side of the polyolefin-based resin film according to any one of claims 1 to 5. A cosmetic adhesive film obtained by further laminating an adhesive layer on the print layer side of the decorative film according to claim 8.