JP2013189000A - Skin material for automobile interior - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a skin material for automobile interior having high designability equivalent to woven fabric or knitted fabric by using nonwoven fabric, and excellent in friction resistance and abrasion resistance.SOLUTION: Printing is performed by an inkjet printing method using radical active energy ray curable ink using pigment as a coloring material, and a surface protective layer having a specified resin composition is provided thereon.

Description

  The present invention relates to an interior skin material excellent in design, which is used as an automobile ceiling or interior material.

  Conventionally, a laminate composed of a base material layer, a cushion material layer, and a skin material layer has been used as an automobile ceiling or interior material. A skin material is a layer which comprises the design surface of a ceiling or interior material, and the thing comprised by the fibrous component is used.

  As a technique for imparting design properties to a skin material, for example, Patent Document 1 discloses the use of a double raschel knitted fabric that can be combined with various knitting structures and yarns as a fabric as a skin material.

  However, a cloth such as a double raschel knitted fabric is expensive, and as an alternative technique, for example, Patent Document 2 discloses a technique of providing a print on the surface of a needle punched nonwoven fabric by gravure printing or screen printing. However, such printing requires a labor and cost for printing, such as the need to prepare a plate for each color. In addition, since advanced printing expression such as gradation cannot be performed, only images with poor design can be printed.

  Patent Document 3 discloses a technique for revealing a design pattern on the surface of a nonwoven fabric by thermal transfer printing or ink jet printing. Inkjet printing is a printing method that forms images by ejecting very small ink droplets from a plurality of nozzles arranged on the print head. It is possible to print very clear and high-definition images. It is. However, the ink-jet ink used in Patent Document 3 is a water-based type, and when used for printing on a permeable material, there are problems in bleeding, penetration, and water resistance of a printed portion.

  As a solution to these problems, ink jet printing using an active energy ray-curable ink such as ultraviolet (UV) or electron beam (EB) has been proposed.

  Since such an active energy ray-curable ink is basically solvent-free, there is almost no risk of environmental load due to volatilization of solvent components and head clogging due to ink drying.

  Further, since polymerization proceeds and cures immediately after irradiation with active energy rays, there is no need for a large-scale drying facility, and the quality of the printed image does not deteriorate due to bleeding or the like. In other words, the polymerization reaction does not start unless a certain amount or more of the active energy ray is irradiated, so that the ink does not change such as thickening, and the ink stays stable for a long time. I can do it.

  When the active energy ray-curable ink having many features as described above is used for imparting the designability of the automobile interior skin material, a very clear and high-definition design can be obtained. However, for example, when an infant touches it with a dirty hand, and the skin material becomes dirty, the printed pattern on the surface of the skin material may be discolored due to friction or wear if it is wiped with a damp cloth, etc. There are problems such as being unable to hold.

JP 2010-202168 A JP-A-1-168540 JP-A-8-296161

  An object of the present invention is to provide a skin material for automobile interior that has a high design property comparable to a woven fabric or a knitted fabric using a nonwoven fabric, and is excellent in friction resistance and wear resistance.

  As a result of intensive studies on the above problems, the present inventors have found that the object can be achieved by a method of combining printing with a specific inkjet ink and a surface protective layer comprising a specific resin composition. It came to be completed.

That is,
(1) A printed pattern such as a design or a letter is provided on at least one surface of a substrate composed of fibrous components by an inkjet printing method using a radical type active energy ray-curable ink having a pigment as a colorant. Furthermore, a skin material for automobile interior, in which a surface protective layer is provided on the printed pattern.
(2) The automobile interior skin material according to item 1, wherein the surface protective layer is an acrylic resin.
(3) The acrylic resin contains 10 to 35% by weight of acrylonitrile and 1 to 5% by weight of N-methylolacrylamide as monomers constituting the acrylic copolymer, and is an emulsion type comprising the acrylic copolymer. The skin material for automobile interior according to Item 2, which is an acrylic resin produced by adding 0 to 60 ppm of formaldehyde to an acrylic copolymer, and applying and drying.
(4) The automobile interior skin material according to any one of Items 1 to 3, wherein the substrate composed of the fibrous component is a nonwoven fabric.

  The skin material for automobile interior according to the present invention has high design properties and excellent friction resistance and wear resistance, and greatly contributes to comfortable comfort in the automobile. Furthermore, since the designability is imparted by the ink jet printing method, it is not necessary to prepare a plate as in the prior art, and effects such as simplification of the manufacturing process and cost reduction can be obtained.

The present invention will be described in detail below.
The base material used in the present invention is not particularly limited, and conventionally used non-woven fabrics, woven fabrics, and knitted fabrics can be used. In order to improve the smoothness of the surface of the substrate, rolling with a hot roll or the like can be performed as necessary.

  As the ink-jet ink used for the printed pattern of the present invention, a radical type active energy ray-curable ink that is generally used can be used. Specific examples include conventionally known acrylic monomers, acrylic oligomers, unsaturated polyesters, and ene / thiol systems. In consideration of friction resistance, it is preferable to use at least one selected from the group consisting of monofunctional acrylates, bifunctional acrylates and polyfunctional acrylates among acrylic monomers, and in particular, use a mixture of two or more types. It is preferable to do. Among acrylic oligomers, it is preferable to use at least one selected from the group consisting of polyester acrylate, urethane acrylate or epoxy acrylate, and it is particularly preferable to use a mixture of two or more.

  The radical active energy ray-curable inkjet ink used in the present invention contains a photopolymerization initiator when UV-cured. It does not specifically limit as a photoinitiator, A benzophenone, phenylphosphine oxide, etc. are mentioned.

  The radical active energy ray-curable inkjet ink used in the present invention contains a colorant composed of a pigment. Examples of the pigment include organic pigments such as azo and phthalocyanine, inorganic pigments such as metal oxides and sulfides, carbon black, and the like.

  In addition to the above components, the radical active energy ray-curable inkjet ink used in the present invention may contain other components such as an inorganic filler, a pigment dispersant, and a viscosity modifier as necessary.

  The raw material monomer of the emulsion type acrylic copolymer constituting the acrylic resin used in the surface protective layer of the present invention is not particularly limited, for example, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, Examples include 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, n-hexyl methacrylate, and lauryl methacrylate. These can be used alone or in combination of two or more.

  The emulsion-type acrylic copolymer used in the present invention includes acrylonitrile. The acrylonitrile content is preferably 10 to 35% by weight as a monomer constituting the acrylic copolymer. The acrylonitrile content contributes to the coating strength, and if it is less than 10% by weight, sufficient coating strength cannot be obtained. If it exceeds 35% by weight, discoloration due to heat during drying occurs.

  The emulsion type acrylic copolymer used in the present invention includes N-methylolacrylamide. The N-methylolacrylamide content is preferably 1 to 5% by weight as a monomer constituting the acrylic copolymer. The N-methylolacrylamide content contributes to the coating strength by crosslinking, and if it is less than 1% by weight, sufficient coating strength cannot be obtained, and if it exceeds 5% by weight, the stability as a coating is deteriorated and at the time of drying. Discoloration due to heat.

  Formaldehyde may be further added to the emulsion type acrylic copolymer used in the present invention. The amount of formaldehyde added is preferably 0 to 60 ppm relative to the acrylic resin solid content of the emulsion type acrylic copolymer. The amount of formaldehyde added contributes to the crosslinking density, but if it exceeds 60 ppm, it will volatilize in the automobile compartment as a volatile organic substance (VOC) and the environment for the human body will deteriorate.

  The glass transition temperature of the emulsion-type acrylic copolymer used in the present invention is not particularly limited and can be appropriately selected depending on the molding conditions, but is generally preferably −10 to −35 ° C. When the temperature is higher than −10 ° C., the coating film becomes hard and surface cracks occur during molding. When the temperature is lower than −35 ° C., the coating film is soft, but the coating surface becomes sticky and does not peel off from the mold during molding. .

  A method for providing a surface protective layer made of an acrylic resin is not particularly limited, and a conventional coating method can be used. Examples include a gravure coater, a bar coater, a rivas coater, a roll knife coater, a doctor coater, a kiss coater, and a foam coater.

The resin amount of the surface protective layer is preferably 8 to ²⁰ g / m ² as the solid content adhesion amount. If it is less than 8 g / m < ² >, the part printed with radical ink cannot be covered uniformly, but friction resistance will worsen. Moreover, when it exceeds 20 g / m < ² >, the problem that the color printed with radical ink discolors or a texture becomes hard will generate | occur | produce.

  Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the present invention is not limited to the examples.

Creation of a sheet for skin material Needle ring was applied to a fiber web made of polyester fiber having a fineness of 2.2 dtex to form a needle punched nonwoven fabric having a basis weight of 190 g / m ² . Thereafter, one surface was rolled at 180 ° C. to obtain a sheet for skin material (hereinafter referred to as a sheet).

Examples 1-10
Radical UV ink (Best Cure IJ made by T & K TOKA Co., Ltd.) was used on the roll hanging surface of the above sheet, and an inkjet printer made by Lucio Co., Ltd. (head manufactured by Konica Minolta IJ Co., Ltd./with 360 dpi / UV irradiation lamp). Printed and given a design pattern. Next, foam-coating is performed on this printed surface with an emulsion type acrylic copolymer composed of the composition shown in Table 1 so that the solid content adheres to 10 g / m ² with the following composition, and then at 180 ° C. The skin material for evaluation was created by drying for 2 minutes.
Formulation Emulsion-type acrylic copolymer 20.0 parts by weight Foam stabilizer (Profan 2021E) manufactured by Sanyo Chemical Industries Co., Ltd. 0.2 parts by weight Water 79.8 parts by weight

Comparative Example 1
Radical UV ink (Best Cure IJ made by T & K TOKA Co., Ltd.) was used on the roll hanging surface of the above sheet, and an inkjet printer made by Lucio Co., Ltd. (head manufactured by Konica Minolta IJ Co., Ltd./with 360 dpi / UV irradiation lamp). Printed and provided with a design pattern, an evaluation skin material was prepared.

Comparative Example 2
A cationic UV ink (EX-UV SP2 manufactured by Konica Minolta IJ Co., Ltd.) is used on the roll hanging surface of the sheet, and an inkjet printer manufactured by Lucio Co., Ltd. (head manufactured by Konica Minolta IJ Co., Ltd./360 dpi / UV irradiation lamp attached) ) To give a design pattern and create an evaluation skin material.

Comparative Examples 3-7
A cationic UV ink (EX-UV SP2 manufactured by Konica Minolta IJ Co., Ltd.) is used on the roll hanging surface of the sheet, and an inkjet printer manufactured by Lucio Co., Ltd. (head manufactured by Konica Minolta IJ Co., Ltd./360 dpi / UV irradiation lamp attached) ) To give a design pattern. Next, foam-coating is performed on this printed surface with an emulsion type acrylic copolymer composed of the composition shown in Table 2 so that the solid content adheres to 10 g / m ² with the following composition, and then at 180 ° C. The skin material for evaluation was created by drying for 2 minutes.
Formulation Emulsion-type acrylic copolymer 20.0 parts by weight Foam stabilizer (Profan 2021E) manufactured by Sanyo Chemical Industries Co., Ltd. 0.2 parts by weight Water 79.8 parts by weight

Comparative Examples 8-10
Radical UV ink (Best Cure IJ made by T & K TOKA Co., Ltd.) was used on the roll hanging surface of the above sheet, and an inkjet printer made by Lucio Co., Ltd. (head manufactured by Konica Minolta IJ Co., Ltd./with 360 dpi / UV irradiation lamp). Printed and given a design pattern. Next, foam-coating was performed on this printed surface with an emulsion type acrylic copolymer composed of the composition shown in Table 3 so that the solid content was 10 g / m ² with the following composition, and then at 180 ° C. The skin material for evaluation was created by drying for 2 minutes.
Formulation Emulsion-type acrylic copolymer 20.0 parts by weight Foam stabilizer (Profan 2021E) manufactured by Sanyo Chemical Industries Co., Ltd. 0.2 parts by weight Water 79.8 parts by weight

  The following evaluation was performed about Examples 1-9 and Comparative Examples 1-9. The results are shown in Table 4 and Table 5.

Evaluation method in the table [Abrasion resistance (wet)]
Test method JIS L 0849 Dye fastness test method against friction
Friction Tester Type II Load 200g x 100 times Judgment method JIS L 0805 Gray scale for contamination
Evaluate in 9 grades of 1 to 5 semi-class units.

[Abrasion resistance]
Test Method JIS L 1096 General Textile Test Method
Method C (Taber type method) Wear wheel: CS-10 Load 500g x 150 times Judgment method Evaluated in 9 steps of the following semi-class units 1 to 5 Grade 4 or higher is acceptable
Grade 5 No fuzz is observed
Grade 4 Fluffing is recognized but not noticeable
Grade 3 Fluff is clearly recognized
Level 2 The fuzz is slightly remarkable
1st class

[Heat-resistant discoloration]
Test method Leave the skin material for evaluation in a dryer at 90 ° C for 1000 hours Judgment method JIS L 0804 Discoloration gray scale
Evaluate in 9 grades of 1 to 5 semi-class units.

  From the results of Tables 4 and 5, the product of the present invention can be used as a car interior covering material excellent in friction resistance, wear resistance and heat discoloration while maintaining excellent design.

Claims (4)

  On at least one surface of a substrate composed of fibrous components, a print pattern such as a design, letters, etc. is provided by an inkjet printing method using a radical type active energy ray-curable ink having a pigment as a colorant, and further printing An automobile interior skin material in which a surface protective layer is provided on the handle.   The skin material for automobile interior according to claim 1, wherein the surface protective layer is an acrylic resin.   The acrylic resin contains 10 to 35% by weight of acrylonitrile and 1 to 5% by weight of N-methylolacrylamide as monomers constituting the acrylic copolymer, and is an emulsion type acrylic copolymer comprising the acrylic copolymer. The skin material for automobile interior according to claim 2, which is an acrylic resin produced by adding 0 to 60 ppm of formaldehyde to the polymer, and applying and drying.   The automotive interior skin material according to any one of claims 1 to 3, wherein the substrate composed of fibrous components is made of a nonwoven fabric.