JP2017226099A - Laminated film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated film having high tear elongation while having chemical resistance.SOLUTION: There is provided a laminated film capable of obtaining chemical resistance and high tear elongation characteristics by a laminated film which comprises a surface layer (A) and a substrate layer (B), wherein the surface layer (A) is laminated at least on one surface of the substrate layer (B), the surface layer (A) is composed of a resin composition comprising 15 mass% or more and 70 mass% or less of the following polymer (X) and 30 mass% or more and 85 mass% or less of the following polymer (Y) based on 100 mass% of polymers contained, the polymer (X) is a vinylidene fluoride-based resin, the polymer (Y) is a copolymer having a domain (y1) compatible with the polymer (X) and a domain (y2) incompatible with the polymer (X) and the substrate layer (B) is composed of a thermoplastic resin.SELECTED DRAWING: None

Description

  The present invention relates to a laminated film.

Acrylic resin is excellent in transparency, weather resistance, workability, and chemical resistance, so it is bonded to the surface of resin molded products, woodwork products, metal molded products, vehicles, furniture, door materials, window frames, baseboards, It is used as a skin material for building materials such as bathroom interiors, a marking film, and a high-intensity reflector coating film. In particular, it is known to provide an effect of enhancing the durability of an internal material by laminating on the outermost surface of a material inferior in weather resistance, scratch resistance and chemical resistance.
However, the conventional acrylic material is a film that is easily torn, and it has been impossible to perform operations such as attaching the film while stretching. For this reason, it is difficult to use laminated films on agricultural films with low durability, marking films using curved surfaces, printing media films, and the like.

Furthermore, in order to improve the film performance of an acrylic resin, an example in which a vinylidene fluoride resin, particularly, polyvinylidene fluoride (PVDF) is incorporated has been reported in the past.
Vinylidene fluoride resin exhibits excellent properties such as weather resistance, flame retardancy, heat resistance, antifouling properties, smoothness, chemical resistance, and durability of materials by being laminated on articles exposed to the outdoor environment It is known to increase.

For example, Patent Document 1 discloses a method for producing a film obtained by melt-kneading an acrylic resin mainly composed of a vinylidene fluoride resin and a methacrylate, and a film having high crystallinity, transparency, and surface smoothness. Is disclosed.
Patent Document 2 discloses a resin composition having both high crystallinity and transparency by using an acrylic polymer having both compatible and incompatible domains in PVDF.

  However, Patent Document 1 does not refer to mechanical properties as a film, and particularly does not refer to tear characteristics necessary for following the flexible film as described above. In addition, a film having a large amount of PVDF as in Patent Document 1 has a limitation on a cooling temperature at the time of production, and there is a possibility that white unevenness due to crystallization is observed when heated in a subsequent process. In Patent Document 2, crystallization is fast, and such white unevenness is not seen, but no mention is made of the tearing properties of films and laminates.

WO2011 / 142453 WO2015 / 146675

  The subject of this invention is providing the laminated | multilayer film which has high tear elongation while having chemical resistance.

  The present inventors have found that the above-mentioned problem is a highly crystalline surface layer, that is, a certain amount of vinylidene fluoride resin, a certain amount of domains compatible with and incompatible with the vinylidene fluoride resin. It has been found that a surface layer formed from a resin composition containing a copolymer is achieved by a film laminated on a base material layer made of a thermoplastic resin.

That is, the present invention has the following features.
(1) A laminated film comprising a surface layer (A) and a base material layer (B),
The surface layer (A) is laminated on at least one surface of the base material layer (B),
The surface layer (A) contains 15% by mass to 70% by mass of the following polymer (X) and 30% by mass to 85% by mass of the following polymer (Y) with respect to 100% by mass of the contained polymer. A resin composition,
Polymer (X): vinylidene fluoride resin
Polymer (Y): a copolymer having a domain (y1) compatible with the polymer (X) and a domain (y2) incompatible with the polymer (X),
The base material layer (B) is a laminated film made of a thermoplastic resin.
(2) The laminated film according to (1), wherein the polymer (Y) is a copolymer containing an acrylic polymer chain.
(3) The laminated film according to (1) or (2), wherein the domain (y1) or the domain (y2) contains a macromonomer unit.
(4) The laminated film according to any one of (1) to (3), wherein the base material layer (B) is made of a thermoplastic resin having a tear elongation of 30% or more.
(5) The laminated film according to any one of claims (1) to (4), wherein the base material layer (B) is made of either a polyvinyl chloride resin or a polyester resin.

  The laminated film of the present invention combines high chemical resistance and tear elongation by using a highly crystalline polymer as a surface layer and combining it with a base material layer made of a thermoplastic resin.

<Polymer (X)>
The polymer (X) of the present invention is a vinylidene fluoride resin. Examples of the vinylidene fluoride resin include a copolymer containing 70% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, or a homopolymer of vinylidene fluoride (PVDF). It is done. The higher the vinylidene fluoride resin content, the better the crystallinity of the vinylidene fluoride resin.

In the case where the vinylidene fluoride resin is a copolymer, examples of the monomer copolymerized with vinylidene fluoride include 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, such as hexafluoropropylene and tetrafluoroethylene. Examples include fluoroalkylene (perfluoroalkene).
Examples of the polymerization method of the vinylidene fluoride resin include known polymerization methods such as suspension polymerization and emulsion polymerization. Depending on the polymerization method, the crystallinity and mechanical properties of the resulting resin differ. In the present invention, suspension polymerization or emulsion polymerization is preferable from the viewpoint of mechanical strength.

As the vinylidene fluoride resin, PVDF is preferable because it has a large difference between the melting point and the decomposition temperature and is suitable for molding.
In the present invention, a vinylidene fluoride resin having a high crystal melting point is preferable. In the present invention, the crystal melting point is JIS K7121, 3. It means the crystal melting peak temperature when measured according to the method described in (2).
The crystalline melting point of the vinylidene fluoride resin is preferably 150 ° C. or higher, more preferably 160 ° C. or higher. The upper limit of the crystal melting point is preferably 170 ° C., which is equal to the crystal melting point of PVDF.

  The mass average molecular weight of the vinylidene fluoride resin is preferably 100,000 to 1,000,000, more preferably 150,000 to 800,000, and still more preferably 180,000 to 700,000 in order to obtain a melt viscosity suitable for molding.

Commercially available vinylidene fluoride resins include, for example, Kynar 720, Kynar 710, Kynar 740, Kynar 760 manufactured by Arkema Co., Ltd .; KF # 850 manufactured by Kureha Co., Ltd .; Solef 1006, Solef 1008 manufactured by Solvay Specialty Polymers Co., Ltd., Solef 1015 Solef 6010, Solef 6012, and Solef 6008.
A vinylidene fluoride resin may be used individually by 1 type, and may use 2 or more types together.

<Polymer (Y)>
The polymer (Y) of the present invention comprises a domain (y1) that is compatible with the polymer (X) (hereinafter also referred to as “compatible domain (y1)”) and a domain that is incompatible with the polymer (X) ( y2) (hereinafter also referred to as “incompatible domain (y2)”).
In the present invention, “compatible” refers to a case where a single Tg is observed in a molded product blended with different polymers. In addition, a different polymer refers to the polymer from which a composition differs mutually. In the present invention, the term “incompatible” refers to a case where Tg derived from each polymer is observed in a molded product obtained by blending different polymers.

In the present invention, “domain” refers to one phase constituting a phase separation structure. When a molded product obtained by blending different polymers or a polymer molded product containing different polymer chains has a phase separation structure, Tg derived from each domain is observed.
The domain (y1) of the polymer (Y) compatible with the polymer (X) is one phase constituting the phase separation structure of the polymer (Y), and a polymer composed of the composition of the phase was created. In this case, it means that a single Tg is observed in a molded product obtained by blending the polymer and the polymer (X).
Similarly, the domain (y2) of the polymer (Y) incompatible with the polymer (X) is one phase constituting the phase separation structure of the polymer (Y), and is composed of the composition of the phase. When a polymer is produced, it means that Tg derived from each polymer is observed in a molded product obtained by blending the polymer and the polymer (X).
Therefore, in a molded article obtained by blending the polymer (Y) containing the compatible domain (y1) and the incompatible domain (y2) and the polymer (X), at least two Tg are usually observed.

  However, it may be difficult to determine compatibility / incompatibility only by the number of Tg. For example, when the Tg after the compatible domain (y1) and the vinylidene fluoride resin are compatible with each other and the Tg of the incompatible domain (y2) is accidentally at the same temperature, the blended molded product has a single Tg. Looks like you have. Therefore, compatibility / incompatibility must be confirmed by changing the blend ratio.

In the present invention, it can be confirmed, for example, as follows, that the polymer (Y) has a domain (y1) compatible with the polymer (X) and an incompatible domain (y2).
The Tg of the polymer (Y) usually shows two peaks from each domain (eg 20 ° C. and 100 ° C.). When this is blended with polymer (X), for example, high temperature Tg (100 ° C.) shifts only at low temperature (60 ° C.). This indicates that the domain that showed a high temperature is compatible with the polymer (X) and the other domains are incompatible.

Examples of the polymer (Y) include a macromonomer copolymer, a graft copolymer, and a block copolymer. From the viewpoint of productivity, a macromonomer copolymer obtained by polymerization using a macromonomer is preferred.
For the synthesis of the macromonomer, the catalytic chain transfer polymerization (CCTP) method is preferred from the viewpoint of the double bond introduction rate and the ease of synthesis.

The polymer (Y) undergoes microphase separation when molded alone.
When the polymer (Y) and the polymer (X) are blended, the polymer (X) is compatible with the compatible domain (y1), and crystallization proceeds in the vicinity of the compatible domain (y1) when cooled.

The phase separation structure of the polymer (Y) is more preferable as the domain size is smaller. Crystallization of the vinylidene fluoride resin is likely to occur, and high crystallinity and high transparency can be easily achieved. Furthermore, the optical performance is less likely to deteriorate due to the difference in refractive index between the phase domains.
The size of each domain is preferably 500 nm or less, more preferably 300 nm or less, and even more preferably 100 nm or less. When the domain size is 500 nm or less, the wavelength in the visible light region is hardly scattered and high transparency can be obtained. The lower limit of the size of each domain is about 5 nm.
The size of the domain means, for example, the longest diameter of a portion corresponding to the island portion in the case of a phase separation structure of a sea-island structure. In the case of a co-continuous structure, the size of the domain means an interphase distance (lateral width). The domain size is measured by TEM observation or the like.

  The phase separation structure of the polymer (Y) alone may be either a sea-island structure or a co-continuous structure. Various physical properties of the molded body depend on the phase separation structure after mixing with the vinylidene fluoride resin.

  The mass average molecular weight (g / mol) of the polymer (Y) is preferably 40,000 to 1,000,000. In order to maintain the mechanical strength when formed into a molded body, it is preferable that the mass average molecular weight is high. However, if the mass average molecular weight is too high, the fluidity is lowered and the moldability is lowered. From the viewpoint of achieving both mechanical strength and formability, 50,000 or more and 750,000 or less are more preferable, and 50,000 or more and 500,000 or less are more preferable.

<Domain (y1)>
The domain (y1) of the polymer (Y) of the present invention is compatible with the vinylidene fluoride resin (polymer (X)).
As a polymer chain which comprises domain (y1), what contains 51 mass% or more of segments compatible with a vinylidene fluoride resin is mentioned, for example. In order to ensure compatibility with the vinylidene fluoride resin, the content is preferably 60% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more.
Examples of the segment include monomer units derived from monomers such as methyl (meth) acrylate, ethyl (meth) acrylate, vinyl acetate, and vinyl methyl ketone. The polymer chain constituting the compatible domain (y1) may contain one kind of the segment alone or two or more kinds.
In the present specification, “(meth) acrylate” means “acrylate” or “methacrylate”.

As a method for introducing the compatible domain (y1) into the polymer (Y), a known method such as making a block chain of a block copolymer or a graft copolymer or blending with a mixture thereof may be used. it can.
Furthermore, as a method for synthesizing them, there are living radical polymerization such as ATRP, anionic polymerization, polymerization using a macromonomer, etc., and polymerization using a macromonomer is preferable from the viewpoint of productivity such as polymerization rate and number of steps. .

The domain (y1) preferably contains a macromonomer unit in that it can be easily introduced into the polymer (Y) by copolymerization and the phase separation structure with the domain size and incompatible domain (y2) can be easily adjusted. . However, the domain (y2) may contain a macromonomer unit as long as a phase separation structure can be formed.
The content of the macromonomer unit in the domain (y1) is preferably 80% by mass or more, and more preferably 90% by mass or more.

As the macromonomer, a commercially available product may be used, or the macromonomer may be produced from the monomer by a known method. Macromonomer production methods include, for example, a method using a cobalt chain transfer agent, a method using an α-substituted unsaturated compound such as α-bromomethylstyrene as a chain transfer agent, and chemically bonding a polymerizable group. The method and the method by thermal decomposition are mentioned.
The average molecular weight (Mw) of the macromonomer for producing the domain (y1) is preferably about 5,000 to 100,000, and more preferably about 10,000 to 50,000.

The macromonomer unit contained in the domain (y1) preferably contains a methyl methacrylate unit from the viewpoint of compatibility with the vinylidene fluoride resin.
The content of the methyl methacrylate unit in the macromonomer unit is preferably 50% by mass or more, more preferably 70% by mass or more, and still more preferably 80% by mass or more.

  From the viewpoint of phase separation, the mass proportion of the domain (y1) in the polymer (Y) is preferably 15 to 60 mass%, more preferably 20 to 55 mass%, further preferably 25 to 50 mass%.

<Incompatible domain (y2)>
As a polymer chain which comprises incompatible domain (y2), what contains 50 mass% or more of segments incompatible with polymer (X) is mentioned, for example. In view of sufficiently ensuring incompatibility with the polymer (X), the content of the segment incompatible with the polymer (X) is preferably 60% by mass or more, more preferably 70% by mass or more, and 80% by mass. The above is more preferable.

Examples of the segment constituting the incompatible domain (y2) include n-propyl (meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, t- Butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, Monomer units derived from alkyl (meth) acrylates such as stearyl (meth) acrylate, isobornyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and benzyl (meth) acrylate; styrene, α-methylstyrene, A monomer unit derived from an aromatic vinyl monomer such as methylstyrene, o-methylstyrene, or t-butylstyrene; a monomer unit derived from a vinyl cyanide monomer such as acrylonitrile or methacrylonitrile; Monomer units derived from glycidyl group-containing monomers such as glycidyl (meth) acrylate; monomer units derived from vinyl carboxylates such as vinyl acetate and vinyl butyrate; olefins such as ethylene, propylene and isobutylene Monomer units derived from monomers; monomer units derived from diene monomers such as butadiene and isoprene; monomers derived from unsaturated carboxylic acid monomers such as maleic acid and maleic anhydride Units are listed.
Further, the domain (y2) may contain a macromonomer unit as described in the domain (y1) as long as a phase separation structure can be formed.
The polymer chain constituting the domain (y2) may contain one kind of these monomer units or may contain two or more kinds.

<Method for producing polymer (Y)>
The polymer (Y) of the present invention contains a polymer chain constituting the compatible domain (y1) and a polymer chain constituting the incompatible domain (y2).
As a production method of the polymer (Y), for example, a known method such as living radical polymerization such as ATRP, anionic polymerization, polymerization using a macromonomer, or the like can be used. Among these, a polymerization method using a macromonomer is preferable from the viewpoint of productivity such as a polymerization rate and the number of steps, and suspension polymerization using a macromonomer is more preferable because it is excellent in environmental compatibility without using an organic solvent.

  Hereinafter, a method for obtaining the polymer (Y) by suspension polymerization using a macromonomer will be described in detail as an example, but even if the polymer (Y) is obtained by other methods, it does not depart from the present invention.

Polymer (Y) is obtained by suspension polymerization of the macromonomer and other monomers. Thereby, the compatible domain (y1) and the incompatible domain (y2) having a macromonomer unit can be introduced into the polymer (Y).
At this time, it is preferable to heat the mixture of the macromonomer and the monomer. As for the heating temperature at the time of the said mixing, 30-90 degreeC is preferable. If heating temperature is 30 degreeC or more, it will become easy to melt | dissolve a macromonomer in another monomer. Moreover, if heating temperature is 90 degrees C or less, volatilization of a monomer can be suppressed.
As for the lower limit of heating temperature, 35 degreeC or more is more preferable. Moreover, as for the upper limit of heating temperature, 75 degrees C or less is more preferable.

When using a radical polymerization initiator in manufacture of a polymer (Y), it is preferable to add a radical polymerization initiator after mixing all the monomers.
The temperature of the monomer mixture when adding the radical polymerization initiator is preferably 0 ° C. or higher. If the temperature at the time of adding a radical polymerization initiator is 0 degreeC or more, the solubility to the monomer of a radical polymerization initiator will become favorable. The temperature of the monomer mixture when adding the radical polymerization initiator is preferably 15 ° C. or more lower than the 10-hour half-life temperature inherent to the radical polymerization initiator. If the temperature at which the radical polymerization initiator is added is 15 ° C. or more lower than the 10-hour half-life temperature inherent to the radical polymerization initiator, stable polymerization can be achieved.

Examples of the radical polymerization initiator include organic peroxides and azo compounds.
Examples of the organic peroxide include 2,4-dichlorobenzoyl peroxide, t-butyl peroxypivalate, o-methylbenzoyl peroxide, bis-3,5,5-trimethylhexanoyl peroxide, and octanoyl peroxide. Oxide, t-butylperoxy-2-ethylhexanoate, cyclohexanone peroxide, benzoyl peroxide, methyl ethyl ketone peroxide, dicumyl peroxide, lauroyl peroxide, diisopropylbenzene hydroperoxide, t-butyl hydroperoxide, di -T-butyl peroxide is mentioned.
Examples of the azo compound include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2,4-dimethyl-4-methoxyvaleronitrile).

Among the above radical polymerization initiators, benzoyl peroxide, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 2, 2'-azobis (2,4-dimethylvaleronitrile) and 2,2'-azobis (2,4-dimethyl-4-methoxyvaleronitrile) are preferable.
A radical polymerization initiator may be used individually by 1 type, and may use 2 or more types together.

The addition amount of the radical polymerization initiator is preferably 0.0001 to 10 parts by mass with respect to 100 parts by mass in total of all monomers in terms of polymerization heat generation control.
The polymerization temperature in suspension polymerization is generally 50 to 120 ° C.

  The polymer (Y) obtained by the above production method can be easily handled as beads by drying after filtration from water.

<Surface layer (A)>
The surface layer (A) of the present invention contains 15% by mass to 70% by mass of polymer (X) and 30% by mass to 85% by mass of polymer (Y) with respect to 100% by mass of the polymer contained. It is a resin composition. In terms of having good tearing properties, the content of the polymer (X) is preferably 20% by mass or more, and more preferably 30% by mass or more.

The resin composition of the present invention may contain an additive as necessary within a range that does not impair the optical performance and mechanical properties of the molded body using the resin composition. The smaller the amount of the additive, the better. The content of the additive is preferably 0 part by mass or more and 20 parts by mass or less, more preferably 0 part by mass or more and 10 parts by mass or less, and 0 parts by mass with respect to 100 parts by mass of the resin composition. More preferred is 5 parts by mass or less.
Examples of additives include ultraviolet absorbers, light stabilizers, heat stabilizers, anti-blocking agents such as synthetic silica and silicon resin powder, plasticizers, antibacterial agents, antifungal agents, bluing agents, and antistatic agents. It is done.

  Examples of the ultraviolet absorber include benzoate compounds, benzophenone compounds, benzotriazole compounds, triazine compounds, salicylate compounds, acrylonitrile compounds, metal complex compounds, hindered amine compounds; Examples include inorganic particles such as ultrafine titanium oxide having a particle diameter of about 0.06 μm and ultrafine particle zinc oxide having a particle diameter of about 0.01 to 0.04 μm. These may be used alone or in combination of two or more.

  As for content of a ultraviolet absorber, 0.1-10 mass parts is preferable with respect to 100 mass parts of resin compositions, for example.

Examples of the light stabilizer include hindered amine-based or phenol-based light stabilizers such as N-H type, N-CH ₃ type, N-acyl type, and N-OR type.
Examples of the heat stabilizer include a phenol-based, amine-based, sulfur-based or phosphoric acid-based antioxidant.
As the ultraviolet absorber or antioxidant, for example, a polymer type in which the aforementioned ultraviolet absorber or antioxidant is chemically bonded to the main chain or side chain constituting the polymer may be used.

  The resin composition can be prepared by blending a predetermined amount of the above essential components and, if desired, optional components and kneading them with a conventional kneader such as a roll, a Banbury mixer, a single screw extruder, a twin screw extruder or the like.

<Base material layer (B)>
The base material layer (B) of the present invention is a thermoplastic resin. A thermoplastic resin having a tear elongation of 30% or more is more preferable. The term “tear elongation” as used herein refers to the elongation in the tensile direction until tearing in the right angle tearing method of JIS-K7128-3.

  A known thermoplastic resin can be used as the resin composition constituting the base material layer (B). Examples include the following. Acrylic resin; ABS resin (acrylonitrile-butadiene-styrene copolymer); AS resin (acrylonitrile-styrene copolymer); polyvinyl chloride resin; polyolefin resin such as polyethylene, polypropylene, polybutene, polymethylpentene; Polyolefin copolymers such as vinyl acid copolymers or saponified products thereof, ethylene- (meth) acrylic acid ester copolymers; polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyarylate, polycarbonate; Polyamide resins such as 6-nylon, 6,6-nylon, 10-nylon and 12-nylon; polystyrene resins; fiber derivatives such as cellulose acetate and nitrocellulose; polyvinyl fluoride, polyester Vinylidene fluoride, polytetrafluoroethylene, ethylene - fluorine-based resins such as tetrafluoroethylene copolymer; or two, or three or more copolymers or mixtures selected from these, complexes, laminates and the like. From the viewpoint of good adhesion to the surface layer (A) and tear elongation, either polyvinyl chloride resin or polyester resin is preferred.

<Laminated film>
The laminated film of the present invention is obtained by laminating the surface layer (A) on at least one surface of the base material layer (B). An adhesive layer or a printing layer (ink layer) may be interposed between (A) and (B).
The lamination ratio is preferably 5 or more and 200 or less for the surface layer (A) with respect to the thickness 100 of the base material layer (B). If the surface layer (A) is too thin, chemical resistance becomes difficult to develop, and if it is too thick, the tearing properties are deteriorated. More preferably, it is 10 or more and 180 or less.

The tear elongation of the laminated film of the present invention is preferably 30% or more, more preferably 40% or more. In the conventional acrylic resin, only a low tear elongation was obtained even when laminated with the base material layer (B) exhibiting a high tear elongation, but the laminated film of the present invention achieves an extremely high tear elongation compared with the conventional acrylic resin.
Moreover, the laminated film of the present invention has high chemical resistance. Examples of chemical resistance include resistance to commonly used organic solvents such as ethanol and hexane.

  Examples of the lamination method include known methods such as coextrusion, adhesive coating, thermal lamination, dry lamination, wet lamination, and hot melt lamination.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.
In the examples, “part” indicates “part by mass”, and “%” indicates “% by mass”.

[Evaluation method]
Each evaluation in an Example and a comparative example was implemented with the following method.

(Evaluation method of resin composition)
(1) Molecular weight and molecular weight distribution Mw and Mn were measured using gel permeation chromatography (GPC) (manufactured by Tosoh Corporation, trade name: HLC-8220) under the following conditions.
Column: TSK GUARD COLUMN SUPER HZ-L (4.6 × 35 mm) and two TSK-GEL SUPER HZM-N (6.0 × 150 mm) connected in series Eluent: Tetrahydrofuran Measurement temperature: 40 ° C.
Flow rate: 0.6 mL / min In addition, Mw and Mn use polymethylmethacrylate (Mp (peak top molecular weight) = 141,500, 55,600, 10,290, and 1,590) manufactured by Polymer Laboratories. It was obtained using a calibration curve prepared in the above.

(Film evaluation method)
(1) Tear test Using a right-angle type test piece obtained by punching the film in the MD direction, a tensile test was performed with a Tensilon universal testing machine RTC-1250A (manufactured by Orientec) in accordance with JIS-K7128-3. The test was carried out at a room temperature of 23 ° C. and a tensile speed of 200 mm / min, and the elongation until complete rupture was defined as tear elongation. Five samples were tested per sample, and the average value was obtained.
(2) Chemical resistance test The test chemical was placed on the film, and the surface after 1 hour was observed at room temperature. The drug was placed in a spot shape with a diameter of about 2 cm. After 1 hour, the chemicals were wiped off and the surface was observed. The chemicals with no change were marked with chemical resistance “◯”, and those with a cloudy or rough surface were marked with chemical resistance “X”. Tests were performed for ethanol and n-hexane.

<Production Example 1>
[Dispersant]
In a reaction vessel having a capacity of 1200 L equipped with a stirrer, a condenser and a thermometer, 61.6 parts of a 17% potassium hydroxide aqueous solution, methyl methacrylate (product name: Acryester M) manufactured by Mitsubishi Rayon Co., Ltd. 19.1 And 19.3 parts of deionized water were charged. Subsequently, the liquid in the reaction apparatus was stirred at room temperature, and after confirming an exothermic peak, it was further stirred for 4 hours. Thereafter, the reaction solution in the reaction apparatus was cooled to room temperature to obtain a potassium methacrylate aqueous solution.

  Next, in a reaction vessel having a capacity of 1050 L equipped with a stirrer, a condenser tube and a thermometer, 900 parts of deionized water, 2-sulfoethyl sodium methacrylate (manufactured by Mitsubishi Rayon Co., Ltd., trade name: Acryester SEM-Na) ) 60 parts, 10 parts of the aqueous potassium methacrylate solution and 12 parts of methyl methacrylate (Acryester M) were added and stirred, and the temperature was raised to 50 ° C. while the inside of the polymerization apparatus was replaced with nitrogen. In addition, 0.08 parts of 2,2′-azobis (2-methylpropionamidine) dihydrochloride (manufactured by Wako Pure Chemical Industries, Ltd., trade name: V-50) was added as a polymerization initiator, The temperature was raised to 60 ° C. After the temperature rise, methyl methacrylate (Acryester M) was continuously added dropwise at a rate of 0.24 parts / minute for 75 minutes using a dropping pump. The reaction solution was held at 60 ° C. for 6 hours and then cooled to room temperature to obtain a dispersant having a solid content of 10% as a transparent aqueous solution.

<Production Example 2>
[Macromonomer]
(Synthesis of cobalt complex)
In a synthesizer equipped with a stirrer, 2.00 g (8.03 mmol) of cobalt (II) acetate tetrahydrate (manufactured by Wako Pure Chemical Industries, Ltd., Wako Special Grade) and diphenylglyoxime (Tokyo) were added in a nitrogen atmosphere. Kasei Chemical Co., Ltd., EP grade) 3.86 g (16.1 mmol) and 100 ml of diethyl ether previously deoxygenated by nitrogen bubbling were added and stirred at room temperature for 2 hours.
Next, 20 ml of boron trifluoride diethyl ether complex (manufactured by Tokyo Chemical Industry Co., Ltd., EP grade) was added, and the mixture was further stirred for 6 hours. The obtained product was filtered, and the solid was washed with diethyl ether and vacuum-dried at 20 ° C. for 12 hours to obtain 5.02 g (7.93 mmol, yield 99%) of a brown complex cobalt complex.

(Synthesis of macromonomer)
In a polymerization apparatus equipped with a stirrer, a cooling tube and a thermometer, 145 parts of deionized water, 0.1 part of sodium sulfate (Na ₂ SO ₄ ) and the dispersant produced in Production Example 1 (solid content 10%) 0 .26 parts was added and stirred to obtain a uniform aqueous solution. Next, 95 parts of methyl methacrylate (acrylic ester M), 5 parts of methyl acrylate (manufactured by Mitsubishi Chemical Co., Ltd.), 0.0016 part of cobalt complex produced by the above method and perocta O (Nippon Oil Corporation) 1) 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, trade name) 0.1 part was added to obtain an aqueous dispersion. Next, the inside of the polymerization apparatus was sufficiently purged with nitrogen, and the aqueous dispersion was heated to 80 ° C., held for 4 hours, then heated to 95 ° C. and held for 1 hour. Thereafter, the reaction solution was cooled to 40 ° C. to obtain an aqueous suspension of macromonomer. This aqueous suspension was filtered through a filter cloth, and the filtrate was washed with deionized water and dried at 40 ° C. for 12 hours to obtain a macromonomer. When analyzed by GPC, Mw was 31,500 and Mn was 14,000.

<Production Example 3>
[Polymer (Y1)]
An aqueous solution of a dispersant was prepared by mixing 145 parts of deionized water, 0.1 part of sodium sulfate and 0.26 part of the dispersant produced in Production Example 1.
In a separable flask with a cooling tube, 40 parts of the macromonomer (hereinafter also referred to as “MM”) synthesized in Production Example 2, 24 parts of methyl methacrylate (acrylic ester M) and n-butyl acrylate (manufactured by Mitsubishi Chemical Corporation) ) 36 parts and 0.1 part of n-octanethiol (manufactured by Tokyo Chemical Industry Co., Ltd.) were heated to 50 ° C. with stirring to obtain a raw material syrup.
After cooling the raw syrup to 40 ° C. or less, 0.3 parts of AMBN (2,2′-azobis (2-methylbutyronitrile), trade name) manufactured by Otsuka Chemical Co., Ltd.) is dissolved in the raw syrup, Obtained.

Next, an aqueous solution of a dispersant was added to the syrup, and then the stirring rotation speed was increased while the atmosphere in the separable flask was replaced with nitrogen by nitrogen bubbling to obtain a syrup dispersion.
The syrup dispersion was heated to 75 ° C., and the external temperature of the separable flask was maintained until a polymerization exothermic peak appeared. After the polymerization exothermic peak appeared, when the syrup dispersion reached 75 ° C., the syrup dispersion was heated to 85 ° C. and held for 30 minutes to complete the polymerization to obtain a suspension.
After the suspension was cooled to 40 ° C. or lower, the suspension was filtered with a filter cloth, the filtrate was washed with deionized water, and dried at 40 ° C. for 16 hours to obtain a polymer (Y1).
Mw of polymer (Y1) was 252,000, Mn was 40,500, and molecular weight distribution (PDI) was 6.2.
The polymer (Y1) was put into a PTFE mold and press molded at 200 ° C. (MINI TEST PRESS-10, manufactured by Toyo Seiki Co., Ltd.) to obtain a film-shaped molded body. The obtained film had a microphase separation (co-continuous structure) structure. The average domain size was 10 μm (microscopic observation). The obtained molded product alone was observed at Tg of 100 ° C. and 20 ° C. Tg was observed at 60 ° C. and 20 ° C. in a film obtained by blending with PVDF which is polymer (X) and molding in the same manner. This is because the domain (y1) of the polymer (Y1) having a Tg of 100 ° C. is compatible with the polymer (X), and the domain of the polymer (Y1) having a Tg of 20 ° C. is non-phase with the polymer (X). This corresponds to the dissolved domain (y2).

[Film (a)]
After preliminarily drying overnight at 60 ° C, 40 parts of PVDF (manufactured by Arkema Co., Ltd., trade name: kynar 720) as polymer (X) and 60 parts of polymer (Y1) prepared in Production Example 3 as polymer (Y) The mixture was dry blended and extruded at a maximum temperature of 220 ° C. by a φ30 mm biaxial kneading extruder (manufactured by Werner & Pfleiderer) to obtain a pellet-shaped molding material (resin composition).
The PVDF used (manufactured by Arkema Co., Ltd., trade name: kynar 720) was a homopolymer composed of vinylidene fluoride units, the crystal melting point was 169 ° C., and the mass average molecular weight was 257000.
The pellets obtained by the above method were pre-dried overnight at 60 ° C., and then extruded at 180 to 200 ° C. at a extrusion temperature of 180 to 200 ° C. by a 30 mm single screw extruder (GM Engineering) equipped with a 150 mm wide T die. A film (a) having a thickness of 130 μm was obtained at a cooling roll temperature of 40 ° C. at 200 ° C. (thickness 112 μm).

<Example 1>
As the surface layer (A), the film (a) produced above is used, and as the base material layer (B), a vinyl chloride film (manufactured by Mitsubishi Plastics Agridream Co., Ltd., product name: Noviace Mirai, thickness 103 μm, tear elongation 95% ) Was used to produce a laminated film. The laminated film was produced using a vacuum laminator (LM-50 × 50-S, manufactured by NPC Corporation) at 140 ° C. under vacuum for 10 minutes, pressing for 1 minute, and holding for 10 minutes. The evaluation results are shown in Table 1.
The film (a) as the surface layer (A) had a phase separation structure (co-continuous structure by microscopic observation). The average domain size was 10 μm (microscopic observation). Domain (y1) contained about 38% macromonomer.
The ratio of the thickness of the surface layer (A) and the base material layer (B) was 112: 103.

<Comparative Example 1>
As the surface layer (A), an acrylic film (manufactured by Mitsubishi Rayon Co., Ltd., acryloprene HBS, thickness 127 μm) (no compatible / incompatible domain structure was observed. Tg was a single 100 ° C.). Except for the above, Comparative Example 1 was obtained in the same manner as Example 1. The evaluation results are shown in Table 1.

<Comparative example 2>
Comparative Example 2 was made without using the surface layer (A) and using only the polyvinyl chloride film (Mitsubishi Resin Agridream Co., Ltd., product name: Noviace Mirai, thickness: 103 μm) as the base material layer (B). The evaluation results are shown in Table 1.

As can be seen from the comparison between Examples and Comparative Example 1, when a conventional acrylic film was used as the surface layer (A), the tear elongation was smaller than that of the base material layer (B) alone, but the surface layer (A ) Is a predetermined polymer composition of the present invention, it was possible to produce a film having high tear elongation and chemical resistance when combined with the base material layer (B).
Further, as can be seen from the comparison between the example and the comparative example 2, if the surface layer (A) is not present, the film has insufficient chemical resistance.
As exemplified above, the laminated film obtained is composed of the surface layer (A) and the base material layer (B) and has a high tear elongation and chemical resistance as long as it has a predetermined composition.

  The laminated film of the present invention is an optical sheet material, food film / design film / agricultural film, printing media film, marking film, film material such as wrapping film, automotive interior material, automotive exterior material, medical member, Suitable for building interior materials and building exterior materials.

Claims (5)

A laminated film comprising a surface layer (A) and a base material layer (B),
The surface layer (A) is laminated on at least one surface of the base material layer (B),
The surface layer (A) contains 15% by mass to 70% by mass of the following polymer (X) and 30% by mass to 85% by mass of the following polymer (Y) with respect to 100% by mass of the contained polymer. A resin composition,
Polymer (X): Vinylidene fluoride resin Polymer (Y): Copolymer having a domain (y1) compatible with the polymer (X) and a domain (y2) incompatible with the polymer (X) B) is a laminated film made of a thermoplastic resin.   The laminated film according to claim 1, wherein the polymer (Y) is a copolymer containing an acrylic polymer chain.   The laminated film according to claim 1 or 2, wherein the domain (y1) or the domain (y2) contains a macromonomer unit.   The laminated film according to any one of claims 1 to 3, wherein the base material layer (B) is made of a thermoplastic resin having a tear elongation of 30% or more.   The laminated film according to any one of claims 1 to 4, wherein the base material layer (B) is made of either a polyvinyl chloride resin or a polyester resin.