JPH0346029B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) This invention relates to a coating composition for vinyl cloth,
More specifically, even when coated as a surface coating on synthetic resin floor sheets, synthetic resin ceiling sheets, and synthetic resin wallpaper materials, the plasticizer from these so-called vinyl cloth materials transfers to the surface coating. Not only does the surface coating film not become sticky, but it also causes surface gloss to develop over time (so-called gloss return phenomenon).
To provide a paint composition for vinyl cloth that is (Conventional Examples and Their Disadvantages) In general, vinyl chloride products, which are the main component of so-called vinyl cloth, are required to be flexible in order to respond to diversification and create designs, three-dimensional effects, softness, etc., and as a result, they are extremely flexible. Many plasticizers (usually
DOP (dioctyl phthalate) and DOA (dioctyl adipate) are 50 to 90% per 100 parts by weight of resin.
(contains some parts). However, although these plasticizers do not cause any problems in their original purpose of softening the hard vinyl cloth, they can be used to coat the surface of the so-called vinyl cloth with a coating agent, especially a glossy emulsion paint. When applied, the plasticizer in the vinyl cloth migrates into the paint film, which has the disadvantage of softening the paint film and making it sticky.The inventors have already tried to eliminate this drawback. He made an invention that allowed him to do so. At the same time, the inventors disclosed this invention as Patent Application No. 33912 of 1981. In this invention, the resin composition of the conventional glossy emulsion paint is composed of an acrylic resin or an acrylic-styrene copolymer emulsion resin, and these acrylic resins are the DOP and DOA in the vinyl cloth.
We focused on the fact that the resin has good compatibility with plasticizers such as
By using acrylic resin or acrylic styrene copolymer resin as an essential component, which contains 50 mol% of acrylonitrile groups and has a glass transition temperature in the range of 30 to 70°C, we aim to eliminate the drawbacks of conventional products. It was wet. Indeed, this invention has succeeded in overcoming the conventional drawbacks, and the phenomenon of the development of tackiness over time is extremely effectively suppressed in the coating film formed with the coating composition for vinyl cloth according to the existing invention. It was hot. However, it has been found that the coating film formed using the coating composition for vinyl cloth according to the existing invention also has the drawback that the gloss returns over time. This gloss return phenomenon is caused by a coating film that is originally not glossy.
This refers to a phenomenon that results in luster over time. The inventors have conducted extensive research into elucidating the cause of this so-called gloss return phenomenon. (Research background) In the course of this research, the inventors found that a coating film composed of a matte emulsion paint composition that lacks the inner luster of conventional vinyl cloth paint compositions has a higher adhesion to the outer layer of vinyl cloth. Although it is bad, the first thing I noticed was that there was almost no tackiness over time and there was no loss of luster. It has been determined that elucidating the cause of this will lead to elucidation of the cause of the phenomenon in which the gloss returns over time in the coating film formed with the coating composition for vinyl cloth according to the existing invention. As a result, conventional coating compositions for vinyl cloth, such as matte emulsion coating compositions, generally have a small amount of acrylic resin, and the extender pigments they contain play a role in suppressing the stickiness of the coating film, making it plastic. It has been found that the agent is difficult to transfer, and even if the plasticizer does transfer, the extender pigment substantially suppresses the development of tackiness. As a result, the plasticizer from the vinyl cloth is present in the coating film formed using the vinyl cloth coating composition according to the instant invention, although the amount is not enough to impart tackiness to the coating film, it is present in a small amount, that is, it imparts gloss to the coating film. As a result, it was found that the coating film formed with the coating composition for vinyl cloth according to the present invention exhibits a phenomenon of return of gloss over time. That is, it has been found that in addition to using a specific resin, it is necessary to add a large amount of pigment, such as in a matte emulsion paint, in order to suppress the phenomenon of gloss return. However, paints with a large amount of pigment added, such as matte emulsion paints, inherently have a major drawback in adhesion, and matte emulsion paints themselves tend to stain easily when used as an outer layer coating on vinyl cloth. There are some facts that aren't great. In the end, they discovered that the ratio of extender pigment to resin is a major factor in suppressing the phenomenon of return of luster, that is, it has a very deep relationship with the difficulty in transferring the plasticizer. (Solution Means) Therefore, the present inventors have conducted extensive research into a coating composition for vinyl cloth that is excellent in the outer layer of vinyl cloth and can suppress the phenomenon of returning gloss. It is characterized by containing an acrylic resin or an acrylic styrene copolymer resin as an essential component and having a glass transition temperature in the range of 30 to 70°C, and 15 to 40% by weight of a scale-like extender pigment. The inventors have discovered that a coating composition for vinyl cloth overcomes all of these conventional drawbacks, and have thus arrived at the present invention. (Structure of the invention) In this invention, 30 acrylonitrile groups are added in the main chain.
Acrylic resin or acrylic styrene copolymer resin containing 50 to 50 mol% and having a glass transition temperature in the range of 30 to 70°C has the general formula (However, R ₁ is hydrogen or methyl group, R ₂ has 1 carbon number
A synthetic resin polymerized from conventionally known monomers such as acrylic esters or methacrylic esters, represented by 1 to 18 alkyl groups, and the main chain of this synthetic resin has 30 to 50 acrylonitrile groups. %, and any selected combination of R groups and R groups whose glass transition point temperature is set at 30 to 70°C can be preferably used. The reason why the above resin is used as the synthetic resin that can be used in this invention is that since it contains an acrylonitrile group in the main chain, the coating film forms a network structure due to the intermolecular cohesive force of this acrylonitrile group, and furthermore, the glass transition temperature This is because increasing the temperature slows down the thermal motion of the molecules of the synthetic resin, and both effects make the coating film more dense, making it difficult for the plasticizer in the vinyl cloth to transfer to the coating film. In this invention, the reason why the content of acrylonitrile groups contained in the main chain is set to 30 mol% or more and 50 mol% or less is that if the acrylonitrile group content is less than 30 mol%, the coating film becomes less dense and becomes plastic. The effect of suppressing agent migration is lost, and conversely, if it exceeds 50 mol %, there are too many hydrophilic acrylonitrile groups, making it unsuitable for emulsion polymerization, which is not preferable in either case. In this invention, the reason why the glass transition temperature of the resin is set to 30°C or more and 70°C or less is that if the glass transition temperature becomes less than 30°C, the density of the coating will be weakened and the plasticizer migration suppressing effect will be lost. If the temperature exceeds 70°C, the coating film becomes hard and problems arise in terms of physical properties as a protective film, which is undesirable in either case. In this invention, 15 to 40% by weight of scaly pigment is used.
However, specific examples of this scaly pigment include:
Preferred examples include mica, talc, etc., and those having an average particle diameter of about 3 to 30 μm are preferably used as the diameter of these scale pigments. In this invention, the blending amount of the scale-like pigment is 15
The reason why it is ~40% by weight is that the scale-like extender pigment is 40% by weight.
If the content exceeds 15% by weight, it is undesirable because the adhesion to vinyl cloth will deteriorate, and if the scale-like extender pigment in the pigment is less than 15% by weight, the resin will not be contained due to the intermolecular cohesive force of the acrylonitrile group. The coating film is formed into a network structure, and by raising the glass transition point temperature, the thermal movement of the synthetic resin molecules is slowed down, and both of these effects increase the density of the coating film, and the plasticizer in the vinyl cloth increases. This is because, in addition to the effect of making it difficult to transfer to the paint film, this scaly pigment physically synergizes with the effect of preventing the plasticizer from penetrating into the paint film and prevents return gloss from being effectively exerted. Note that other additives such as emulsifiers may be mixed into the coating composition according to the present invention. The paint according to the present invention may be applied by a conventional method using a known coating device, ie, a brush, a roller, a spray, or the like. (Effects) The coating composition for vinyl cloth according to the present invention having the above structure contains 30 to 50% mole of acrylonitrile groups in the main chain and has a glass transition temperature in the range of 30 to 70°C. This paint composition for vinyl cloth is characterized by containing acrylic resin or acrylic styrene copolymer resin as an essential component and 15 to 40% by weight of a scale-like extender pigment, so it is different from conventional paints of this type. It also eliminates the drawbacks of the previously disclosed paint compositions for vinyl cloth, has excellent adhesion when applied to the outer layer of vinyl cloth, and eliminates not only the development of tackiness over time but also the phenomenon of loss of luster. This is a coating composition for vinyl cloth that has the effect of The effects of this invention will be made clearer by describing Examples and Comparative Examples below. Examples 1 to 4 Paint compositions for vinyl cloth having the compositions shown in Table 1 below as main components were prepared.

[Table] Comparative Examples 1 to 8 Paint compositions for vinyl cloth having the compositions shown in Table 2 below as main components were prepared.

[Table] Test method Each paint was applied onto a soft PVC sheet using a 6 mil applicator, and after drying the coating solution at 50°C for 7 days, the tackiness test and adhesion test were conducted on the coating film using the following method. (Adhesion test) A piece of dust paper was torn to an appropriate size, held down with the right thumb for 10 seconds, and adhesion was determined by determining whether the paper remained or came off. Removable: ○ Removable but with some shine remaining: △ Paper adhesion: × After being left in a container for 2 weeks, the state of gloss of the right and left halves of the coating film was visually compared and judged. Restoration of luster: × No restoration of luster: ○ Cannot be said either: △ The results are summarized in Table 3.

【table】

[Table] * The material of Comparative Example 6 could not be polymerized, and the material of Comparative Example 7 cracked when applied to a PVC sheet, making the test impossible.
As can be seen from the above results, it can be seen that the coating composition for vinyl cloth according to the present invention has excellent effects.

Claims (1)

[Claims] 1 An essential component is an acrylic resin or an acrylic styrene copolymer resin that contains 30 to 50% mole of acrylonitrile groups in the main chain and has a glass transition temperature in the range of 30 to 70°C, and has a scale-like constitution. A paint composition for vinyl cloth, characterized in that it contains 15 to 40% by weight of a pigment.