JP7117163B2 - Resin composition and molded film - Google Patents

Description

The present invention relates to resin compositions and molded films.

Films attached to the surfaces of objects used outdoors, such as vehicle exteriors and signboards, are required to have long-term weather resistance, heat resistance, and the like. For example, films made of vinyl chloride resin generally have excellent printability in addition to weather resistance and heat resistance, and are used in various applications as described above.

Patent Document 1 below discloses a resin composition containing a vinyl chloride resin. Specifically, vinyl chloride resin is mixed with acrylonitrile-butadiene-styrene resin (ABS resin), acrylonitrile-styrene resin (AS resin), ethylene-vinyl acetate resin, or the like, and lauryl tin mercaptocarboxylate is used as a stabilizer. A resin composition is disclosed. Further, Patent Document 2 below discloses a molding decorative sheet to which heat-resistant resin obtained by copolymerizing vinyl chloride resin with α-methylstyrene and N-phenylmaleimide or maleic anhydride is added.

JP-A-62-290749 JP-A-5-4309

As described above, films made of vinyl chloride resin generally have excellent weather resistance, heat resistance, and the like. However, films made of vinyl chloride resin tend to have poor shape stability at high temperatures. Therefore, when a film made of vinyl chloride resin is put on the surface of a molded article having a three-dimensional shape, it may shrink, exposing a part of the molded article or peeling off from the molded article. For example, the decorative sheet for molding of Patent Document 2 softens at 70° C. to 80° C., and therefore has insufficient shape stability when used in fields such as building materials and automobile decoration.

Further, in the examples of Patent Document 1, it is shown that the yellowing index becomes 17 after 5 minutes when the resin composition is kneaded with rolls set at 190°C. Therefore, it is difficult to form a film from the resin composition of Patent Document 1 at a high temperature. Thus, conventional resin compositions containing vinyl chloride resins are insufficient in high-temperature film-forming properties.

Further, when the surface of a molded product having a three-dimensional shape is covered with a molded film, the molded film is required to conform to the shape of the surface so that it can be deformed.

Accordingly, an object of the present invention is to provide a resin composition that can be formed into a film having high-temperature film-forming properties, shape stability and followability, and a molded film having a resin layer composed of the resin composition.

In order to solve the above problems, the resin composition of the present invention is characterized by containing 100 parts by mass of a vinyl chloride resin and 20 parts by mass or more and 300 parts by mass or less of an acrylonitrile-styrene copolymer.

Further, the resin composition of the present invention preferably contains 66 parts by mass or more of the acrylonitrile-styrene copolymer.

Moreover, it is preferable that the resin composition of the present invention further contains an acrylic processing aid comprising an acrylic resin having a weight average molecular weight of 280,000 or more and 3,100,000 or less.

Moreover, it is preferable that the degree of polymerization of the vinyl chloride resin is 800 or more and 1000 or less.

Moreover, in order to solve the above problems, the molded film of the present invention is characterized by comprising a resin layer comprising the resin composition of the present invention.

ADVANTAGE OF THE INVENTION According to this invention, the molded film which has the resin layer which has the resin composition which has high temperature film-forming property, and can be made into the film which has shape stability and conformability, and the said resin composition is provided.

1 is a diagram schematically showing a cross-section of a formed film according to an embodiment of the invention; FIG.

The embodiments illustrated below are intended to facilitate understanding of the present invention, and are not intended to limit and interpret the present invention. The present invention can be modified and improved from the following embodiments without departing from its gist.

[Molding film]
FIG. 1 is a diagram schematically showing a cross section of a formed film according to an embodiment of the invention. The molded film 1 of this embodiment includes a resin layer 2 and an adhesive layer 3 laminated on one side of the resin layer 2 .

The pressure-sensitive adhesive layer 3 is a layer made of a pressure-sensitive adhesive provided for attaching the formed film 1 to various adherends. The pressure-sensitive adhesive that constitutes the pressure-sensitive adhesive layer 3 is not particularly limited, and examples thereof include (meth)acrylic resin-based pressure-sensitive adhesives. (Meth)acryl means one or both of acryl and methacryl.

The adhesive layer 3 is formed, for example, by coating one surface of the resin layer 2 with an adhesive.

The resin layer 2 is a layer made of a resin composition which will be described later. Moreover, the thickness of the resin layer 2 is not particularly limited. The thickness of the resin layer 2 is, for example, 50 μm or more and 500 μm or less, preferably 100 μm or more and 300 μm or less.

The resin layer 2 is formed by curing a resin composition which will be described later. The resin layer 2 is formed, for example, by calendering.

The resin layer 2 may be transparent or colored. The molded film 1 including the resin layer 2 of the present embodiment is suitable as, for example, a film, a sticker, or the like to be affixed to the interior or exterior parts of a vehicle or to the surface of an object installed outdoors.

The molded film 1 may be a single-layer film including only the resin layer 2 or may be a film including layers other than the resin layer 2 and the adhesive layer 3 . For example, between the resin layer 2 and the pressure-sensitive adhesive layer 3 or on the surface of the resin layer 2 opposite to the pressure-sensitive adhesive layer 3 side, a single-layer or multiple-layer printed layer or the like may be provided. A method for forming the printed layer is not particularly limited. The printed layer is formed, for example, by coating a resin composition containing a resin, a coloring agent, a solvent, etc. by a method such as screen printing.

[Resin composition]
The resin composition constituting the resin layer 2 of this embodiment contains a vinyl chloride resin, an acrylonitrile-styrene copolymer, and an acrylic processing aid.

The vinyl chloride resin contained in the resin composition forming the resin layer 2 preferably has a polymerization degree of 800 or more and 1000 or less. By setting the polymerization degree of the vinyl chloride resin to 800 or more, the resin layer 2 can be provided with appropriate tensile strength. In addition, when the degree of polymerization of the vinyl chloride resin is 1000 or less, the temperature for setting the viscosity of the resin composition constituting the resin layer 2 to an appropriate range is excessively increased when forming the resin layer 2. can be suppressed. Therefore, excessive application of heat to the resin composition forming the resin layer 2 during the film forming process of the resin layer 2 can be suppressed, and yellowing of the resin layer 2 can be suppressed.

The acrylonitrile-styrene copolymer contained in the resin composition forming the resin layer 2 generally has a higher glass transition temperature than vinyl chloride resin. Therefore, when the resin composition constituting the resin layer 2 contains an acrylonitrile-styrene copolymer, the glass transition temperature of the resin composition increases compared to the case where only vinyl chloride resin is used, and the resin layer 2 after molding is improved. Shape stability can be improved. The glass transition temperature is the peak value of tan δ measured using a dynamic viscoelasticity measuring device DMA.

The resin composition forming the resin layer 2 contains 20 parts by mass or more and 300 parts by mass or less of an acrylonitrile-styrene copolymer with respect to 100 parts by mass of the vinyl chloride resin. By adding the acrylonitrile-styrene copolymer in this way, the resin layer 2 can be suppressed from becoming brittle, and the molded film 1 can be a tough film, as compared with a film formed of a vinyl chloride resin alone. The resin composition forming the resin layer 2 preferably contains 66 parts by mass or more and 300 parts by mass or less of the acrylonitrile-styrene copolymer with respect to 100 parts by mass of the vinyl chloride resin. By adding the acrylonitrile-styrene copolymer in this manner, thermal decomposition of the vinyl chloride resin can be suppressed, and yellowing of the resin layer 2 due to heat can be suppressed.

The acrylic processing aid contained in the resin composition forming the resin layer 2 refers to a (meth)acrylic resin having a weight average molecular weight of 280,000 or more and 3,100,000 or less. As the acrylic processing aid, for example, a (meth)acrylic acid ester copolymer can be used. The (meth)acrylic acid ester-based copolymer is a copolymer obtained by copolymerizing acrylic acid esters, methacrylic acid esters, or acrylic acid ester and methacrylic acid ester. As acrylic acid esters or methacrylic acid esters, those having 1 to 18 carbon atoms in the alkyl group are preferred. Specific examples of acrylic acid esters include acrylic acid esters such as methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, and 2-ethylhexyl acrylate. Examples of methacrylic acid esters include methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, and 2-ethylhexyl methacrylate.

The content of the acrylic processing aid contained in the resin composition forming the resin layer 2 is preferably 1 part by mass or more and 6 parts by mass or less with respect to 100 parts by mass of the vinyl chloride resin. When the content of the acrylic processing aid is 1 part by mass or more, appropriate tensile strength can be imparted to the resin layer 2 . Therefore, the shape stability of the resin layer 2 can be improved. In addition, when the content of the acrylic processing aid is 6 parts by mass or less, it is possible to suppress the decrease in the surface gloss of the resin layer 2 and the occurrence of flow marks during film formation.

The weight average molecular weight of the acrylic processing aid is preferably 280,000 or more and 3,100,000 or less. When the weight average molecular weight of the acrylic processing aid is 280,000 or more, the resin layer 2 can be given an appropriate tensile strength, and the resin layer 2 can be prevented from being broken or stretched excessively when stretched during molding. Further, by setting the weight-average molecular weight of the acrylic processing aid to 3,100,000 or less, it is possible to suppress the occurrence of residual stress in the resin layer 2 after molding.

<Other ingredients>
The resin composition of this embodiment may contain other components as needed. Other components include pigments, plasticizers, lubricants, stabilizers, antioxidants, ultraviolet absorbers, antistatic agents, and the like.

For example, when the resin composition constituting the resin layer 2 contains a lubricant, a stabilizer, or the like, yellowing of the resin layer 2 due to friction with calendar rolls when forming the resin layer 2 by calendar film formation is suppressed. can be In addition, when the resin composition forming the resin layer 2 contains a Ba/Zn-based or Zn-based stabilizer, the thermal decomposition of the vinyl chloride resin can be suppressed during film formation of the resin layer 2 .

(Properties of Resin Composition)
The glass transition temperature of the resin composition constituting the resin layer 2 is preferably 80° C. or higher, more preferably 100° C. or higher, by adjusting the formulation. By setting the glass transition temperature of the resin composition constituting the resin layer 2 to 80° C. or higher, the shape stability of the resin layer 2 can be improved. Drawdown can be suppressed. Moreover, the glass transition temperature of the resin composition forming the resin layer 2 is preferably 130° C. or lower. By setting the glass transition temperature of the resin composition to 130° C. or less, the temperature during film formation of the resin layer 2 can be made lower than the temperature at which the vinyl chloride resin starts to decompose. Therefore, yellowing of the resin layer 2 can be suppressed.

Moreover, it is preferable that the storage elastic modulus of the resin composition constituting the resin layer 2 is adjusted within the following range by adjusting the formulation.

The storage elastic modulus (E′) at 80° C. of the resin composition forming the resin layer 2 is preferably 1100 MPa or more and 2600 MPa or less. By setting the storage modulus (E′) of the resin composition at 80° C. to 1100 MPa or more, the shape stability of the resin layer 2 after molding can be improved. In addition, by setting the storage elastic modulus (E′) of the resin composition at 80° C. to 2600 MPa or less, the resin layer 2 is suppressed from becoming too hard, and the resin layer 2 and the adhesive layer 3 and other The handleability when laminating a film or the like can be improved.

Moreover, the storage elastic modulus (E′) at 140° C. of the resin composition constituting the resin layer 2 is preferably 1 MPa or more and 7 MPa or less. Since the storage elastic modulus (E′) of the resin composition constituting the resin layer 2 at 140° C. is 1 MPa or more, the strength and flexibility of the resin layer 2 are insufficient when molding the resin layer 2 at high temperatures. It can be suppressed that the resin layer 2 is damaged due to Further, by setting the storage elastic modulus (E′) of the resin composition constituting the resin layer 2 to 7 MPa or less at 140° C., the conformability of the resin layer 2 during molding can be improved.

Moreover, the storage elastic modulus (E′) at 180° C. of the resin composition constituting the resin layer 2 is preferably 0.2 MPa or more and 5 MPa or less. By setting the storage modulus (E′) of the resin composition to 0.2 MPa or more at 180° C., the resin layer 2 can be easily peeled off from the calender rolls when the resin layer 2 is formed by calendering. obtain. Further, by setting the storage modulus (E′) of the resin composition at 180° C. to 5 MPa or less, generation of frictional heat can be suppressed when the resin layer 2 is formed by calendering. Therefore, even if the resin composition is kneaded at a high temperature of 180° C. or higher, discoloration of the resin layer 2 due to thermal decomposition of the vinyl chloride resin can be suppressed. From the same point of view, the storage elastic modulus (E') at 180°C of the resin composition constituting the resin layer 2 is more preferably 3 MPa or less.

Although the present invention has been described using the above embodiment as an example, the present invention is not limited to the above embodiment. The resin composition of the present invention may contain at least 100 parts by mass of a vinyl chloride resin and 20 parts by mass or more and 300 parts by mass or less of an acrylonitrile-styrene copolymer, and other components are not essential components.

EXAMPLES Hereinafter, the content of the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these.

(Examples 1 to 13 and Comparative Examples 1 to 7)
Each material was mixed with a ribbon blender according to the formulations shown in Tables 1 and 2 to obtain resin compositions according to Examples 1 to 13 and Comparative Examples 1 to 7.

After pre-kneading the resin composition obtained by mixing as described above at 150°C for 10 minutes using a pressure kneader, the resulting pre-kneaded product was passed through two rolls set at 160°C. The mixture was melt-kneaded for 10 minutes to obtain a melt-kneaded product. Then, the melt-kneaded product was made into a film having a thickness of about 250 μm by calender film formation to form molded films according to Examples 1 to 13 and Comparative Examples 1 to 7. Four calender rolls arranged in an inverted L shape with a roll temperature of 185° C. or more and 195° C. or less were used to form these formed films.

The details of each material indicated by trade name in Tables 1 and 2 are as follows.
Kanevinyl S1001N: vinyl chloride resin with a degree of polymerization of 1000, manufactured by Kaneka Corporation Kanevinyl S1008: vinyl chloride resin with a degree of polymerization of 800 manufactured by Kaneka Corporation XM-25: acrylic resin, Metabrene H-602 manufactured by Kaneka Corporation: Acrylic resin, Clarastic K-2540A manufactured by Mitsubishi Chemical Co., Ltd.: ABS resin, Clarastic S-3811 manufactured by Nippon A&L Co., Ltd.: ABS resin, Clarastic S-1200B manufactured by A&L Japan Co., Ltd.: ABS resin, manufactured by A&L Co., Ltd. Tellalloy A-15X: AS resin, ADEKA CIZER PN-1430 manufactured by Kaneka Corporation: Polyester plasticizer, METABLEN P-551A manufactured by ADEKA Corporation: Acrylic processing aid, glass transition temperature of 71°C, weight average molecular weight of 1,450,000 , Mitsubishi Chemical Corporation METABLEN P-530A: acrylic processing aid, glass transition temperature of 70 ° C., weight average molecular weight of 3.1 million, Mitsubishi Chemical Corporation METABLEN P-570A: acrylic processing aid, glass transition temperature is 59 ° C., weight average molecular weight is 280,000, Mitsubishi Chemical Corporation CR-90-2: white pigment made of titanium oxide, Ishihara Sangyo Co., Ltd. ADEKA STAB LS-16: acrylic lubricant, ADEKA Corporation BU-ST : Butyl stearate, Kawaken Fine Chemicals Co., Ltd. AC-6A: Polyolefin wax, Honeywell ADEKA STAB SP-2002: Zn-based + hydrotalcite stabilizer, ADEKA Co., Ltd. ADEKA STAB CPS-1: Ba / Zn-based + hydro Talcite stabilizer, ADEKA Co., Ltd. ADEKA STAB SP-83: β-diketone, ADEKA Co., Ltd. ADEKA STAB RX-406: Zn-based stabilizer, ADEKA CO., LTD. 1001: Zn-based + phosphite stabilizer, ADEKA Co., Ltd. ADEKA STAB CPL-46: Liquid perchlorate stabilizer, ADEKA CORPORATION ADEKA STAB AC-400: Ba / Zn-based stabilizer, ADEKA Co., Ltd. ADEKA STAB AC -292: Zn-based stabilizer, manufactured by ADEKA Co., Ltd. Adekastab CPL-1563: Phosphite + hindered amine light stabilizer (HALS), manufactured by ADEKA Co., Ltd. Adekastab C: Phosphite, manufactured by ADEKA Co., Ltd.

<Evaluation method>
The films according to the above examples and comparative examples were evaluated by the methods described below. Evaluation results are shown in Tables 1 and 2.

(High temperature film formability)
Regarding the molded films according to Examples 1 to 13 and Comparative Examples 1 to 7 formed as described above, the color immediately after formation (initial) and the color after standing for 1 hour in an environment of 180 ° C. The colors were measured with a colorimeter CM-3600d manufactured by Konica Minolta, and the color value (b ^* ) and yellowness index (YI) were evaluated according to the following criteria. Although the resin composition is not placed in a high-temperature environment for even one hour in a normal film manufacturing process, the color after long-time heating was confirmed in consideration of the possibility of reuse of the resin composition. If the resin composition is left in a high-temperature environment for a long time, hydrolysis of the acrylic resin, polyester, etc. is accelerated by hydrogen chloride generated by decomposition of the vinyl chloride resin, and yellowing tends to occur.
A: Less than 5 B: 5 or more and less than 7 C: 7 or more and less than 10 D: 10 or more and less than 15 E: 15 or more

(Followability)
Each of the formed films according to Examples 1 to 13 and Comparative Examples 1 to 7 was laminated with an adhesive layer prepared as described below and allowed to stand at 23° C. and 50% RH for 1 week. After that, a vacuum forming machine Forming 480 manufactured by Seiko Sangyo Co., Ltd. was applied to the surface of a three-dimensional structure made of ABS resin having a hemispherical shape with a radius of 30 mm and a depression with a diameter of 10 mm and a depth of 30 mm at the top of the sphere. Each molded film was coated at a molding temperature of 140° C. to obtain a molded body. Then, the followability of the formed film in the depth direction of the depression was confirmed and evaluated according to the following criteria.
A: 25 mm or more B: 20 mm or more and less than 25 mm C: 18 mm or more and less than 20 mm D: less than 18 mm

(Preparation of adhesive layer)
An adhesive was prepared by adding 0.1 part by mass of an epoxy-based cross-linking agent TETRAD-C (manufactured by Mitsubishi Gas Chemical Co., Ltd.) to 100 parts by mass of Nisetsu KP-3075 (manufactured by Nippon Carbide Industry Co., Ltd.). This adhesive was applied to a release-treated polyethylene terephthalate (PET) film (PET75GS, manufactured by Lintec Corporation) so that the thickness after drying was 40 μm, and dried at 80°C. Thus, an adhesive layer was formed on the PET film.

(shape stability)
The pressure-sensitive adhesive layer was laminated on each of the formed films according to Examples 1 to 13 and Comparative Examples 1 to 7, and allowed to stand at 23° C. and 50% RH for 1 week. After that, using a vacuum forming machine Forming 480 manufactured by Seiko Sangyo Co., Ltd., at a forming temperature of 140 ° C. and an areal draw rate of 300%, each formed film was coated on a 7 cm square ABS plate, and then the central part was 5 cm square. cut with The cut portion was placed in a dryer at 80° C. for 48 hours, and the amount of shrinkage of the formed film was measured and evaluated according to the following criteria.
A: Less than 1% B: 1% or more and less than 1.5% C: 1.5% or more and less than 2% D: 2% or more

(glass transition temperature, storage modulus)
The formed films according to Examples 1 to 13 and Comparative Examples 1 to 7 were cut into a size of 10 mm × 20 mm, respectively, and the glass transition temperature was measured using a dynamic viscoelasticity measuring device DMA (manufactured by Hitachi High-Tech Science Co., Ltd.). and storage modulus (E') were measured. The storage elastic modulus (E′) was measured at 80° C., 140° C. and 180° C. In each case, the measurement length was 10 mm, the heating rate was 2° C./min, and the frequency was 10 HzA. Also, the glass transition temperature and storage modulus (E') were evaluated according to the following criteria.
Evaluation criteria for glass transition temperature:
A: 110°C or higher, B: 100°C or higher, C: 80°C or higher, D: less than 80°C Evaluation criteria for storage modulus (E') at 80°C:
A: 1800 MPa or more, B: 1400 MPa or more, C: 1100 MPa or more, D less than 1100 MPa Evaluation criteria for storage modulus (E') at 140°C:
A: 1 MPa or more and less than 3 MPa, B: 3 MPa or more and less than 5 MPa, C: 5 MPa or more and less than 7 MPa, D Evaluation criteria for storage modulus (E') at 8 MPa or more and 180 ° C.:
A: 0.2 MPa or more and less than 1 MPa, B: 1 MPa or more and less than 3 MPa, C: 3 MPa or more and less than 5 MPa, D5 MPa or more

As shown in Tables 1 and 2, the resin compositions according to Examples are excellent in high-temperature film-forming properties, and the resin compositions according to Examples provide molded films having followability and shape stability. On the other hand, Comparative Examples are inferior in any one of high-temperature film forming properties, conformability and shape stability.

As described above, the resin composition of the present invention has high-temperature film-forming properties and can form a film having shape stability and followability.

As described above, according to the present invention, there is provided a resin composition capable of forming a film having high-temperature film-forming properties and shape stability and conformability, and a molded film having a resin layer composed of the resin composition. It is expected to be provided and used in the field of decoration of vehicles such as automobiles.

DESCRIPTION OF SYMBOLS 1... Molded film 2... Resin layer 3... Adhesive layer

Claims (5)

Contains 100 parts by mass of vinyl chloride resin and 20 parts by mass or more and 300 parts by mass or less of an acrylonitrile-styrene copolymer, and has a storage modulus (E') at 80 ° C. of 1100 MPa or more and 2600 MPa or less, and at 140 ° C. Storage elastic modulus (E′) is 1 MPa or more and 7 MPa or less, storage elastic modulus (E′) at 180° C. is 0.2 MPa or more and 5 MPa or less, and has a thickness of 100 μm or more and 300 μm or less. resin layer
have
A molded film for covering the surface of a molded article having a three-dimensional shape . 2. The molded film for covering the surface of a molded article having a three-dimensional shape according to claim 1 , wherein the resin composition contains 66 parts by mass or more of the acrylonitrile-styrene copolymer. The resin composition contains 150 parts by mass or more of the acrylonitrile-styrene copolymer
A molded film for covering the surface of a molded article having a three-dimensional shape according to claim 1, characterized in that: 4. Any one of claims 1 to 3, wherein the resin composition contains 1 part by mass or more and 6 parts by mass or less of an acrylic processing aid comprising an acrylic resin having a weight average molecular weight of 280,000 or more and 3,100,000 or less. A molded film for covering the surface of a molded product having a three-dimensional shape as described in 1. above . 5. The molded film for covering the surface of a molded product having a three-dimensional shape according to any one of claims 1 to 4 , wherein the degree of polymerization of the vinyl chloride resin is 800 or more and 1000 or less.

Images