JP5790895B2 - Aqueous surface treatment agent for plastic molded article to be stretch-molded and plastic molded article using the same - Google Patents

Description

  The present invention relates to an aqueous surface treatment agent for plastic molded articles that is stretch-molded and has a matte (matte) tone on the surface of various articles and can give a higher-class design, and plastic molding using the same About goods.

  Various articles are often coated with a paint on the surface for the purpose of improving design properties and imparting a high-class feeling. For example, the surface of plastic molded products such as housings for home appliances, housings for electronic devices such as personal computers, mobile phones, and smartphones, and interior and exterior materials for automobiles should be given a high-class design. In addition, a surface treatment agent is used. Conventionally, many of these surface treatment agents are solvent-based. However, since a volatile organic compound (hereinafter abbreviated as “VOC”) is generated and the environmental load is large, the amount of VOC emissions can be reduced. Accordingly, the surface treatment agent is being made water-based.

  As an aqueous surface treating agent that makes the surface of various articles matte, for example, an aqueous urethane-based resin using a polyol component containing a polyolefin polyol and an aqueous matte surface treating agent containing polyurethane fine particles as a matting agent have been proposed. (For example, refer to Patent Document 1). However, this water-based matte surface treatment agent is an aqueous surface treatment agent that produces a matte feeling mainly by a matting agent. For example, when a coating process is formed on a film or sheet and then subjected to a molding process such as stretching, There was a problem that the gloss decreased and the gloss increased.

  A method of applying two coating agents containing a matting agent repeatedly has been proposed (see, for example, Patent Document 2), as a matte feeling that does not decrease when a molding process such as stretching is performed. However, this method requires a coating process and a drying process a plurality of times, and has a problem in productivity.

  Therefore, there has been a demand for an aqueous surface treatment agent that does not decrease the matte feeling even if it is subjected to a molding process such as stretching, and can impart a sufficient matte feeling to various articles by a single coating.

JP 2003-342549 A JP 2006-176615 A

  The problem to be solved by the present invention is that the surface of various articles has a matte tone, can impart a more luxurious design, and the coating does not deteriorate the matte feeling even if it is subjected to a molding process such as stretching. However, it is providing the water-based surface treating agent for plastic molded products which are stretch-molded and obtained by one coating, and a plastic molded product using the same.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that an aqueous surface treatment agent using a combination of aqueous polyurethane and an aqueous polyester or aqueous acrylic resin as another resin has a mat-like surface for various articles. And found that a coating film that can give a more luxurious design and does not deteriorate the matte feeling even when subjected to molding such as stretching can be obtained by a single coating. Completed.

  That is, the present invention is an aqueous surface treatment agent containing an aqueous polyurethane (A), an aqueous polyester (B) or an aqueous acrylic resin (C), a matting agent (D), and a crosslinking agent (E). The plastic molding to be stretch-molded is characterized by containing 5 to 60 parts by mass in total of the aqueous polyester (B) and the aqueous acrylic resin (C) with respect to 100 parts by mass of the aqueous polyurethane (A). The present invention relates to an aqueous surface treating agent for articles and a plastic molded article using the same.

  The aqueous surface treating agent of the present invention has a matte tone on the surface of various articles, can give a higher-grade design, and has a coating film that does not deteriorate the matte feeling even if it is subjected to a molding process such as stretching. Since it is obtained by a single coating, it can be used as a treatment agent on the surface of various articles. In particular, it can be suitably used for plastic molded products, and among plastic molded products, it is suitably used for TPO leather and TPO sheets which are molded products of thermoplastic olefin (hereinafter abbreviated as “TPO”). be able to.

  The aqueous surface treating agent for a plastic molded article to be stretch-molded according to the present invention includes an aqueous polyurethane (A), an aqueous polyester (B) or an aqueous acrylic resin (C), a matting agent (D), and a crosslinking agent (E ) Containing 5 to 60 parts by mass in total of the aqueous polyester (B) and the aqueous acrylic resin (C) with respect to 100 parts by mass of the aqueous polyurethane (A). Is.

  The aqueous polyurethane (A) may be any polyurethane that can be dissolved or dispersed in an aqueous medium, and among them, a polyurethane having a carboxyl group and / or a hydroxyl group is preferable. Among these aqueous polyurethanes (A), examples of the method for producing a polyurethane having a hydroxyl group include a method of reacting an excess amount of polyol and / or glycol with polyisocyanate to obtain a polyurethane having a hydroxyl group at the terminal, an isocyanate group terminal And a method of obtaining a polyurethane having a hydroxyl group by reacting 2-urethane prepolymer with amino alcohol such as 2-aminoethanol, 2-aminoethylethanolamine and diethanolamine, aminophenol and the like. On the other hand, examples of the method for producing a polyurethane having a carboxyl group include a method of using a compound having a carboxyl group as a raw material in the urethanization reaction.

  Examples of the polyol used as a raw material for the aqueous polyurethane (A) include polyester polyols, polyether polyols, polycarbonate polyols, polyacetal polyols, polyacrylate polyols, polyester amide polyols, polythioether polyols, and polybutadiene polyols such as polybutadiene. It is done. Among these, polycarbonate polyol is preferable because of its excellent durability. Moreover, as a compound which has a carboxyl group used as a raw material of the polyurethane which has a carboxyl group, 2,2'- dimethylol propionic acid, 2,2'- dimethylol butanoic acid, 2,2'- dimethylol butyric acid, 2 2,2'-dimethylol valeric acid and the like. Among these, 2,2'-dimethylolpropionic acid is preferable.

  Among the water-based polyurethanes (A) obtained by the above production method, a polycarbonate-based water-based polyurethane using a polycarbonate polyol as a raw material is preferable because of high coating film strength. Moreover, the said water-based polyurethane (A) can be used individually or can be used together 2 or more types.

  The aqueous polyester (B) may be any polyester that can be dissolved or dispersed in an aqueous medium, and is preferably a water-dispersed polyester resin. The water-dispersed polyester resin is obtained by imparting water dispersibility to the polyester resin by introducing a hydrophilic group. Examples of commercially available products include the “Vylonal” series of Toyobo Co., Ltd.

  The number average molecular weight (Mn) of the aqueous polyester (B) is preferably in the range of 5,000 to 500,000, more preferably in the range of 10,000 to 300,000, and in the range of 150,000 to 250,000. Further preferred. The glass transition temperature of the aqueous polyester (hereinafter abbreviated as “Tg”) is preferably in the range of −30 to 130 ° C., more preferably in the range of −20 to 100 ° C., and in the range of −10 to 80 ° C. Further preferred. The water-based polyester (B) can be used alone or in combination of two or more.

  The aqueous acrylic resin (C) may be an acrylic resin that dissolves or disperses in an aqueous medium, and is an aqueous solution produced by emulsion polymerization in which an acrylic monomer is used as a main raw material and polymerization is performed in an aqueous medium using an emulsifier. Examples include acrylic resin emulsions, self-emulsifying water-based acrylic resins that have been polymerized in an organic solvent using an acrylic monomer having a carboxyl group, then neutralized with a base, and dispersed in an aqueous medium. It is done.

  As the aqueous acrylic resin (C), various modified acrylic resins such as a urethane-modified aqueous acrylic resin modified with aqueous polyurethane and an aqueous silicon acrylic resin modified with a silane compound can also be used. The aqueous acrylic resin (C) can be used alone or in combination of two or more.

  The blending amount of the aqueous polyurethane (A), the aqueous polyester (B) and the aqueous acrylic resin (C) improves the matte feeling and makes the coating film strength sufficient. Therefore, 100 parts by mass of the aqueous polyurethane (A) On the other hand, the total of the aqueous polyester (B) and the aqueous acrylic resin (C) is in the range of 5 to 60 parts by mass, preferably 10 to 50 parts by mass, and more preferably 20 to 45 parts by mass. .

  Examples of the matting agent (D) include silica particles, organic beads, calcium carbonate, magnesium carbonate, barium carbonate, talc, aluminum hydroxide, calcium sulfate, kaolin, mica, asbestos, mica, calcium silicate, alumina silicate, and the like. Is mentioned.

  Examples of the silica particles include dry silica and wet silica. Among these, dry silica is preferred because of its high scattering effect and wide gloss value adjustment range. Moreover, since it becomes easy to disperse | distribute in a composition, the dry-type silica surface-modified with the organic compound is more preferable. The average particle diameter of these silica particles is preferably in the range of 2 to 14 μm, more preferably in the range of 3 to 12 μm.

  As the amount of the silica particles used, since a gloss value capable of obtaining a desired matte design can be achieved, the total resin content of the aqueous polyurethane (A), the aqueous polyester (B) and the aqueous acrylic resin (C) is 100 mass. The range of 0.1-40 mass parts is preferable with respect to parts, and the range of 10-30 mass parts is more preferable.

  Examples of the organic beads include acrylic beads, urethane beads, silicon beads, and olefin beads.

  Said mat agent (D) can be used individually or can be used together 2 or more types.

  Examples of the crosslinking agent (E) include urea resin-based crosslinking agents such as oxazoline, carbodiimide, polyisocyanate, blocked isocyanate, epoxy, polysiloxane, aziridine, and alkylated melamine, and hydrazide-based crosslinking agents. Among these, carbodiimide is preferable from the viewpoint of crosslinking performance and safety. Moreover, these crosslinking agents (E) can be used alone or in combination of two or more. As a usage-amount of the said crosslinking agent (E), it is 0 with respect to 100 mass parts of total resin parts of the said water-based polyurethane (A), water-based polyester (B), and water-based acrylic resin (C) from a viewpoint of coating film strength. The range of 5-30 mass parts is preferable, and the range of 2-25 mass parts is more preferable.

  In addition to the aqueous polyurethane (A), aqueous polyester (B), aqueous acrylic resin (C), matting agent (D) and crosslinking agent (E), the aqueous surface treating agent of the present invention includes polyolefin wax (F). Can be blended.

  Among the polyolefin waxes (F), even if a solvent such as alcohol comes into contact with the coating film, the trace (solvent trace) hardly remains and the solvent resistance is improved, so the melting range is 140 to 180 ° C. A thing of 145-175 degreeC is more preferable, and what is 150-170 degreeC is further more preferable. Examples of such polyolefin wax (F) include polyethylene wax and polypropylene wax. These polyolefin waxes (F) can be used alone or in combination of two or more. In the present invention, when two or more types of polyolefin waxes (F) are used in combination, the melting range is the melting range of the mixture. The melting range is measured in accordance with JIS test method K0064-1992.

  Among the above-mentioned polyolefin waxes (F), those having polypropylene wax as the main component are preferable because solvent traces can be reduced. Moreover, as the usage-amount of the said polyolefin wax (F), since the reduction effect of a solvent trace and the coating-film intensity | strength can be improved, the said water-based polyurethane (A), water-based polyester (B), and water-based acrylic resin (C) The range of 0.1-20 mass parts is preferable with respect to 100 mass parts of total resin content, and the range of 3-15 mass parts is more preferable.

  In the aqueous surface treating agent of the present invention, in addition to the components (A) to (F), various surfactants, antifoaming agents, leveling agents, viscoelasticity adjusting agents, antifoaming agents, wetting agents, dispersing agents, Preservatives, film formers, plasticizers, penetrants, fragrances, bactericides, acaricides, fungicides, UV absorbers, antioxidants, antistatic agents, flame retardants, dyes, pigments (eg, titanium white, Bengala, phthalocyanine, carbon black, permanent yellow, etc.) may be added.

  The plastic molded article of the present invention has a coating film of the aqueous surface treating agent of the present invention. In addition, examples of articles include housings for home appliances (refrigerators, washing machines, air conditioners, televisions, etc.), housings for electronic devices (computers, mobile phones, smartphones, etc.), musical instruments (pianos, electric tones, electronic musical instruments, etc.) Materials: Interior materials for automobiles or railway vehicles (instrument panels, door trims, headlinings, tonneau covers, etc.), building materials or furniture materials (wallpaper, decorative sheets for plywood, decorative sheets for steel plates, leather for chairs, etc.), Examples include packaging materials (such as wrapping films). Among these plastic molded products, the aqueous surface treating agent for plastic molded products to be stretch-molded according to the present invention is preferably used for TPO leather and TPO sheet among these plastic molded products.

  Hereinafter, the present invention will be described specifically by way of examples.

Example 1
Aqueous polyurethane (“Hydran WLS-210” manufactured by DIC Corporation, polycarbonate-based aqueous polyurethane, nonvolatile content: 35% by mass) 49 parts by mass (17.15 parts by mass as aqueous polyurethane), aqueous polyester (“Vironal” manufactured by Toyobo Co., Ltd.) MD-1100 ", water-dispersed polyester resin, number average molecular weight: 20,000, Tg: 40 ° C, nonvolatile content: 30% by mass) 15.3 parts by mass (4.59 parts by mass as aqueous polyester), cross-linking agent (Nisshinbo Chemical Co., Ltd.) “Carbodilite E-04” manufactured by Co., Ltd., 4.2 parts by mass of carbodiimide-based crosslinking agent, matting agent (“ACEMATT 3300” manufactured by Evonik Degussa Co., Ltd.), silica particles whose surface is organically treated and average particle diameter : 9.5 μm) 4 parts by mass, polypropylene wax (Micro Powder) “MICROMATETE 1213UVW” manufactured by s company; melting part 150 to 156 ° C. 1.4 parts by mass, nonionic surfactant (“Neugen EA-157” manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 0.1 parts by weight, fluorine interface Uniformity of 0.1 parts by mass of activator (DIC Corporation "Megafac F-444"), viscoelasticity modifier (San Nopco "SN Thickener 612NC") 0.9 parts by mass and ion-exchanged water 25 parts by mass To obtain an aqueous surface treating agent (1).

[Preparation of sample for evaluation]
The aqueous surface treating agent (1) obtained above was converted into a bar coater No. 14 was applied onto a TPO sheet (thickness 0.4 mm) and then dried at 120 ° C. for 1 minute to obtain an evaluation sample.

[Production of vacuum formed products]
Using the vacuum forming machine (“Vacuum Forming Machine Forming 300X” manufactured by Seiko Sangyo Co., Ltd.), the evaluation sample obtained above is subjected to vacuum forming so that the area ratio is 350% to obtain a vacuum formed product. It was.

[Measure gloss value]
About the coating surface of the aqueous surface treating agent of the sample for evaluation obtained above, the gloss value (“GM-268Plus” manufactured by Konica Minolta Optics Co., Ltd.) is used for each 60 ° gloss value before and after vacuum forming. And measured.

[Evaluation of moldability]
The change rate of the 60 ° gloss value of the coating film surface of the aqueous surface treatment agent before and after the vacuum molding measured above was calculated, and the molding processability was evaluated according to the following criteria. The change rate of the 60 ° gloss value was calculated by the following formula (1).
A: The rate of change is less than 50%.
B: The rate of change is 50% or more and less than 100%.
C: The rate of change is 100% or more.

(Example 2)
The aqueous polyester used in Example 1 was an aqueous polyester (Toyobo Co., Ltd. “Vironal MD-1200”, water-dispersed polyester resin, number average molecular weight: 15,000, Tg: 67 ° C., nonvolatile content: 34% by mass) Except that the amount of ion-exchanged water was changed to 26.8 parts by mass to 13.5 parts by mass (4.59 parts by mass as aqueous polyester), the aqueous surface treating agent (2) was added. Obtained.

(Example 3)
The aqueous polyester used in Example 1 was an aqueous polyester (Toyobo Co., Ltd. “Vylonal MD-1480”, water-dispersed polyester resin, number average molecular weight: 15,000, Tg: 20 ° C., nonvolatile content: 25 mass%). Except that the amount of ion-exchanged water was changed to 21.9 parts by mass to 18.4 parts by mass (4.6 parts by mass as aqueous polyester), the aqueous surface treating agent (3) was added. Obtained.

Example 4
The water-based polyester used in Example 1 was water-based polyester (“Vironal MD-1930” manufactured by Toyobo Co., Ltd., water-dispersed polyester resin, number average molecular weight: 20,000, Tg: −10 ° C., nonvolatile content: 31% by mass). The surface treatment agent (4) was obtained in the same manner as in Example 1 except that the amount of ion-exchanged water was changed to 25.5 parts by weight to 0.8 parts by weight (4.59 parts by weight as aqueous polyester). It was.

(Example 5)
15.3 parts by weight of water-based polyester used in Example 1 (“Cirrus PC-751” manufactured by Toagosei Co., Ltd., water-based silicon acrylic resin, nonvolatile content: 45% by mass) (7.02 as water-based acrylic resin) The aqueous surface treating agent (5) was obtained in the same manner as in Example 1 except that the amount of ion-exchanged water was changed to 25 parts by mass.

(Example 6)
The aqueous polyester used in Example 1 was 10.2 parts by mass (4.59 as an aqueous acrylic resin) based on an aqueous acrylic resin (“Boncoat HY-364” manufactured by DIC Corporation, urethane-modified aqueous acrylic resin, nonvolatile content: 45% by mass). The aqueous surface treating agent (6) was obtained in the same manner as in Example 1 except that the amount of ion-exchanged water was changed to 30.1 parts by mass.

(Example 7)
The aqueous polyester used in Example 1 was 9.2 parts by mass (4.6 mass as an aqueous acrylic resin) based on an aqueous acrylic resin (“Boncoat VF-1040” manufactured by DIC Corporation, aqueous acrylic resin emulsion, nonvolatile content: 50 mass%). Part) was carried out in the same manner as in Example 1 except that the amount of ion-exchanged water was changed to 31.1 parts by mass to obtain an aqueous surface treating agent (7).

(Comparative Example 1)
60.9 parts by mass (21.3 parts by mass as aqueous polyurethane) of water-based polyurethane (DIC Corporation “Hydran WLS-210”, polycarbonate-based aqueous polyurethane, nonvolatile content: 35% by mass), cross-linking agent (manufactured by Nisshinbo Chemical Co., Ltd.) “Carbodilite E-04”, 4.2 parts by weight of carbodiimide-based crosslinking agent, matting agent (“ACEMATT 3300” manufactured by Evonik Degussa Co., Ltd.), silica particles produced by a dry method and subjected to organic treatment on the surface, average particle size: 9. 5 μm) 4 parts by mass, polypropylene wax (“MICROMATETE 1213UVW” manufactured by Micro Powders, Inc .; melting range 150-156 ° C.) 1.4 parts by mass, nonionic surfactant (“Neugen EA-157” manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) ) 0.1 parts by mass, fluorosurfactant (DIC stock) Co., Ltd. “Megafac F-444”) 0.1 part by mass, viscoelasticity modifier (San Nopco “SN Thickener 612NC”) 0.9 part by mass and ion-exchanged water 28.4 parts by mass were mixed uniformly. Thus, an aqueous surface treating agent (R1) was obtained.

  The aqueous surface treating agents (2) to (7) and (R1) obtained in the above Examples 2 to 7 and Comparative Example 1 were carried out in the same manner as in Example 1, and the measurement of the 60 ° gloss value and the moldability were performed. Evaluation was performed.

  Table 1 shows the composition of the aqueous surface treatment agents (1) to (7) and (R1) obtained in Examples 1 to 7 and Comparative Example 1, measurements of 60 ° gloss values, and evaluation results of moldability. Show.

  From the results shown in Table 1, the aqueous surface treatment agents (1) to (7) of Examples 1 to 7 which are aqueous surface treatment agents of the present invention have a change rate of 60% gloss value of 57% or less. It was found that there was little change in mat feeling on the surface of the coating film, and the moldability was good even when the molding process with stretching was performed.

  On the other hand, Comparative Example 1 is an example in which the aqueous polyester (B) or the aqueous acrylic resin (C) used in combination with the aqueous polyurethane (A) is not blended in the present invention, but the change rate of the 60 ° gloss value is 711%. It was found that the change was very large and the molding processability was insufficient.

Claims (5)

  An aqueous surface treatment agent comprising an aqueous polyurethane (A), an aqueous polyester (B) or an aqueous acrylic resin (C), a matting agent (D), and a crosslinking agent (E), wherein the aqueous polyurethane (A ) A water-based surface treatment agent for plastic molded products that is stretch-molded, containing 5 to 60 parts by mass in total of the water-based polyester (B) and the water-based acrylic resin (C) with respect to 100 parts by mass. .   The aqueous surface treating agent for plastic molded articles to be stretch-molded according to claim 1, wherein the aqueous polyurethane (A) is a polycarbonate-based aqueous polyurethane.   The aqueous surface treating agent for a plastic molded article to be stretch-molded according to claim 1 or 2, wherein the crosslinking agent (E) is carbodiimide.   Furthermore, the aqueous surface treating agent for plastic molded articles which is stretch-molded according to any one of claims 1 to 3, further comprising a polyolefin wax (F).   A plastic molded article having a coating film of the aqueous surface treating agent for a plastic molded article to be stretch-molded according to any one of claims 1 to 4, wherein the plastic molded article is stretch-molded. .