JP2856932B2 - Coating composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating composition for coating articles having a polyvinyl chloride layer on the surface to impart excellent antifouling performance.

[0002]

2. Description of the Related Art Conventionally, as a method for preventing contamination on the surface of an article, a method of applying an acrylic copolymer solution mainly composed of methyl methacrylate or a mixed solution of an acrylic copolymer and polyvinyl chloride has been used. Many have been implemented.

[0003] However, in these methods, weather resistance,
Bleed phenomenon on the surface of plasticizer which is added and blended for the purpose of imparting flexibility to articles whose surface consists of polyvinyl chloride film, such as synthetic leather, wall covering, tarpaulin, etc. Was not able to be prevented, and as a result, dirt easily adhered, and the dirt prevention effect was insufficient.

Further, (1) α having an OH group in the molecule,
A surface treatment agent for polyvinyl chloride obtained by blending a polyisocyanate compound with an acrylic copolymer obtained by copolymerizing a β-ethylenically unsaturated monomer, and (2) α, β containing an OH group in the molecule -A surface treatment agent for polyvinyl chloride in which a polyvinyl chloride resin and a polyisocyanate compound are blended with an acrylic copolymer obtained by copolymerizing an ethylenically unsaturated monomer is also known (Japanese Patent Publication No. 14929).

However, the surface treatment agent of (1) generally has a hard texture and has a problem in use in synthetic leather and tarpaulin applications requiring bending characteristics, and (2)
With the surface treatment agent, although the hand becomes soft, the bleeding phenomenon of the surface of the plasticizer cannot be prevented as in the case of the above, and there is a problem that the stain prevention effect is reduced.

Further, from acrylic acid or methacrylic acid alkyl esters, hydroxyalkyl-containing esters of α, β-ethylenically unsaturated carboxylic acids, specific fluorine-containing monomers, and other copolymerizable vinyl monomers, There is also a method of obtaining an acrylic copolymer solution by solution polymerization (Japanese Patent Laid-Open No. 63-61032), but since the polymerization method is solution polymerization, the number average molecular weight is at most 1,000 to 50,000.
When the molecular weight is low, the film strength is low, and when the composition is more flexible depending on the monomer ratio, there is a problem that the surface blocking property and the stain prevention effect are reduced.

Further, a surface treatment agent for polyvinyl chloride obtained by adding a fluorine-based surfactant or a silicon-based surfactant to an acrylic copolymer solution mainly composed of methyl methacrylate is also known. Alternatively, the surfactant was dropped off by rainwater or the like, and there was a problem in that the effect of preventing contamination due to aging with use was reduced.

[0008]

SUMMARY OF THE INVENTION The present invention has been studied in view of the above-mentioned conventional problems, and as a result, by means completely different from the conventional one, the present invention is rich in flexibility, excellent in bending characteristics, and free from surface blocking problems. In addition, a coating composition that can suppress the bleeding phenomenon of the plasticizer without causing any stains on the treated film itself and with no decrease in the stain prevention effect over time is obtained.

That is, the present invention provides a coating composition having excellent flexibility and flexibility and an excellent stain prevention effect.
(A) 60-90% by weight of methyl methacrylate, (b) 2-20% by weight of an α, β-ethylenically unsaturated monomer containing a fluorine element in the molecule, (c) other copolymerizable monomer Coating composition comprising an acrylic copolymer having a number average molecular weight of 100,000 to 1,000,000 obtained by suspension polymerization of a monomer comprising 8 to 20% by weight of a polymer and a polymerization initiator, and an organic solvent. It is intended to provide a coating composition obtained by mixing another mixed resin .

[0010]

Hereinafter, the present invention will be described in detail.

The acrylic copolymer constituting the coating composition of the present invention is characterized in that it contains elemental fluorine in the molecule, and (a) 60-90% by weight of methyl methacrylate;
(b) a monomer comprising 2 to 20% by weight of an α, β-ethylenically unsaturated monomer containing a fluorine element in the molecule, and (c) a monomer comprising 8 to 20% by weight of another copolymerizable monomer. It is produced by a suspension polymerization method using a polymerization initiator such as azobisisobutyronitrile and di-tert-butyl peroxide.

[0012] Suspension polymerization in the present invention, a surfactant such as polyvinyl alcohol in water addition, the above water
The insoluble monomer mixture is stirred, and for example, azobisisobutyronitrile is used as a polymerization initiator in a range of 0.008 to 0.012% by weight based on 100% by weight of the monomer. It is a method of reacting for 5 hours, and the number average molecular weight of the obtained acrylic copolymer is preferably in the range of 100,000 to 1,000,000.

In the coating composition of the present invention, the range of the number average molecular weight of the above-mentioned acrylic copolymer is particularly important. Even when the vinyl chloride layer is thinned, it has excellent gas barrier properties due to its high molecular weight, can prevent bleeding on the surface of the plasticizer, and can provide a tough film without taking a crosslinked form when used. You can do it.

[0014] Acrylic by the aforementioned solution polymerization is the number means an average molecular weight, number average molecular weight of 100,000 lower acrylic copolymer in terms of polystyrene in GPC is a number average molecular weight (gel permeation chromatography) analysis Similar to the copolymers, there are problems with the film strength, surface blocking properties under flexible blending, stain prevention effects, etc., and when the film is formed on an article made of polyvinyl chloride, Bleeding on the surface of the plasticizer added and blended for the purpose of imparting flexibility cannot be prevented, and as a result, the stain prevention effect becomes insufficient.

Further, in the case of an acrylic copolymer having a number average molecular weight higher than 1,000,000, the viscosity of the coating composition is too high, and there is a problem in uniform coating properties on articles.

Next, the monomers constituting the acrylic copolymer for obtaining the coating composition of the present invention will be described. Methyl methacrylate as the component (a) is 60 to 60% of the total monomer composition. 90% by weight is appropriate, and if it is less than 60% by weight, the effect of preventing the film from being soiled by the obtained coating composition cannot be obtained.
If it exceeds 90% by weight, there is a problem that the film becomes hard and cracks occur.

As the component (b), the fluorine element-containing α, β-ethylenically unsaturated monomer is suitably used in an amount of 2 to 20% by weight of the total monomer composition. If the content exceeds 20% by weight, water and oil repellency of the fluorine-containing α, β-ethylenically unsaturated monomer is too large, and there is a problem of adhesion to an article to be treated. Since the fluorine element-containing α, β-ethylenically unsaturated monomer is expensive, there is a problem that the cost of the treating agent is increased and the market competitiveness of the treated article is lost.

The other copolymerizable monomer of component (c) is used to adjust the hardness of the acrylic copolymer, or if it is possible to crosslink with a compound capable of reacting with active hydrogen such as a polyisocyanate compound. occupied for, or a urethane urea resin
In order to improve the compatibility with the mixed resin , an appropriate type is selected and copolymerized, and 8 to 20% by weight of the total monomer composition is appropriate.

The fluorine-containing α, β-ethylenically unsaturated monomer (b) used in the present invention includes 2,2,2-trifluoroethyl acrylate and 2,2,3,3-tetrafluoroethyl acrylate. Propyl acrylate, 1H, 1H, 5H-octafluoropentyl acrylate, 1H, 1H, 2H, 2H-heptadecafluorodecyl acrylate, β- (perfluorooctyl) ethyl methacrylate, 2,2,2-trifluoroethyl methacrylate, 2 , 2,3,3-tetrafluoropropyl methacrylate, 1H, 1H, 5H-octafluoropentyl methacrylate, 1H, 1H, 2H, 2H-heptadecafluorodecyl methacrylate, 2,2,3,4,4,4-hexa Fluorobutyl methacrylate, β- (perfluorooctyl) ethyl acrylate, 3 {4 [1-trifluoromethyl-2,2-bis [bis (trifluoromethyl) fluoromethyl] ethynyloxy] benzo Oxy} 2-hydroxypropyl methacrylate and the like can be used.

The other copolymerizable monomers of component (c) include α, β-ethylenically unsaturated carboxylic acids, for example, acrylic acid, in order to adjust the hardness of the acrylic copolymer. Derivatives such as methacrylic acid, itaconic acid, maleic anhydride, fumaric acid, maleic acid or alkyl esters or amides thereof, and styrene, alkylstyrene and acrylonitrile can also be used.

The alkyl esters of α, β-ethylenically unsaturated carboxylic acids include methyl acrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, n-propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, butyl acrylate, butyl methacrylate, Acrylamide, methacrylamide, diacetone acrylamide, diacetone methacrylamide, lauryl acrylate, lauryl methacrylate, stearyl acrylate, stearyl methacrylate, hexyl acrylate, 2-ethylhexyl methacrylate, heptyl acrylate,
Heptyl methacrylate and the like can be used.

Next, mixing to be mixed with the acrylic copolymer
As the resin, a polyurethane resin, a polyurethane urea resin, polyurea resin, fluorine resins, acrylic resins, silicone
Over down resin, there are vinyl chloride resins, etc., that one or its
It is possible to use copolymers or mixtures of these resins.
Wear.

The acrylic copolymer is mixed with the above-mentioned mixture.
In order to improve the compatibility with the resin , a quaternized compound such as dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate may be used in addition to the above-mentioned other copolymerizable monomers of component (c). Should be used.

The above resin composition is a coating composition of the present invention.
Prevents the transfer of plasticizer to the product and keeps the effect of preventing contamination
While used to improve flexibility and bending resistance
Since, the amount used, its the acrylic copolymer
It is preferable that the solid content ratio is equal to or less than the same amount, and the amount is equal to or less than the same amount.
When it is higher, the effect of preventing the migration of the plasticizer is reduced, and the effect of preventing contamination is reduced.

There are no particular restrictions on the organic solvent, except for those that significantly inhibit the dissolution of the film-forming components of the treating agent. Examples of the organic solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, diethyl ketone, cyclohexanone,
Ketone solvents such as dimethyl oxide, isophorone and methyl-n-amyl ketone, ester solvents such as ethyl formate, ethyl acetate and n-butyl acetate, and aromatic solvents such as toluene and xylene can be used.

The coating composition of the present invention is, for example, a product having a polyvinyl chloride layer as the outermost layer, a foamed or non-foamed polyvinyl chloride layer formed on a base fabric or paper, or Depending on the type of polyvinyl chloride sheet, specifically polyvinyl chloride leather, wall covering, table cloth, polyvinyl chloride film, etc., it is used after adjusting to an appropriate resin solid content. Min 5
Preferably, it is used in the range of about 30% by weight.

This is because the solid content of the resin greatly affects the change in the viscosity of the processing solution. For example, if the content is less than 5% by weight, the viscosity is too low, and if it exceeds 30% by weight, the viscosity is too high. Is also not preferred because of poor coating suitability.

Further, additives can be added to the coating composition of the present invention in order to further improve the effect of preventing contamination and other physical properties.

As an additive for improving the stain prevention effect, addition of an organopolysiloxane such as silicone resin or silicone oil is effective, and the purpose is to improve the adhesion to articles.
Alternatively, a polyisocyanate compound can be blended for the purpose of increasing the hardness of the coating film. In this case, OH is used as the other copolymerizable monomer of the component (c).
Group-containing α, β-ethylenically unsaturated monomers such as 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 2-hydroxy-3-chloropropyl acrylate, 2 -Hydroxy-3-chloropropyl methacrylate, allyl alcohol, glycidyl methacrylate and the like may be used in combination.

As the polyisocyanate compound, an aliphatic, aromatic or alicyclic compound having three or more isocyanate groups in a molecule is used, and a commercially available yellowing type or non-yellowing type is generally used. (For example, trade names Coronate L, Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.) may be used.

In addition, when the coating composition of the present invention is matted, a conventionally known matting agent such as silica, white carbon, calcium carbonate, clay, talc, polyethylene fine powder and polycarbonate is added. It may be used by dispersing.

When the coating composition of the present invention is applied to the target article, various coating methods such as a doctor knife method, a gravure coating method, a roll coater method, and a reverse roll coater method can be used. .

Articles that have been subjected to a surface treatment using the coating composition of the present invention may be stained on their surfaces, for example,
It shows an excellent stain-preventing effect on dirt that tends to remain as stains such as dust, soot, cigarette tar, lipstick, oil-based magic ink, water-based magic ink, oil, curry, ketchup, coffee, etc. It has excellent lubricity and flexibility.

[0034]

Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. All parts in the examples are parts by weight.

Example 1 (Preparation of Acrylic Copolymer) (1-1) A reaction vessel equipped with a stirrer, a thermometer and a reflux condenser was charged with 1050 parts of distilled water and 0.4 part of polyvinyl alcohol having a polymerization degree of 1500. And dissolved.

In this reactor, methyl methacrylate 365 was added.
Parts, 2,2,2-trifluoroethyl methacrylate 45 parts, 2-
Ethylhexyl methacrylate 18 parts, 22 parts of 2-hydroxypropyl methacrylate and 0.45 parts of azobisisobutyronitrile were blended, and a uniformly stirred and dissolved solution was added.
The mixture was stirred for 6 hours under reflux to obtain an acrylic copolymer.

The obtained copolymer was thoroughly washed with water and dried, and then dissolved in 2025 parts of methyl ethyl ketone and 2025 parts of toluene to obtain a coating composition (A) adjusted to a solid concentration of 10%. The number average molecular weight in terms of polystyrene of this coating composition (A) as determined by GPC analysis was 478,000.

(1-2) Coating compositions (B) and (C) in the same manner as (1-1) of Example 1 using monomers in the monomer composition ratio shown in Table 1. , (D).

Comparative Example 1 Coating compositions (E) to (I) were prepared in the same manner as in Example 1 (1-1) using monomers in the monomer composition ratio shown in Table 1. ).

[0040]

[Table 1]

Example 2 100 parts of the coating composition (B) obtained in (1-2) of Example 1 was added to a polyvinyl chloride resin (trade name: MA-800).
F, Shin-Etsu Chemical Co., Ltd.) 20% solution of tetrahydrofuran 30
After uniformly stirring, a coating composition (J) was obtained.

Comparative Example 2 100 parts of the coating composition (B) obtained in (1-2) of Example 1 was added to a polyvinyl chloride resin (trade name: MA-800).
F, manufactured by Shin-Etsu Chemical Co., Ltd.)
0 parts were added and stirred uniformly to obtain a coating composition (K).

Example 3 The coating composition (D) 100 obtained in (1-2) of Example 1
Part is polyvinylidene fluoride resin (trade name, Kynar 46)
0, dimethylformamide 1 of Pennwalt Corporation)
100 parts of a 0% solution was added, and the mixture was stirred uniformly to obtain a coating composition (L).

Example 4 100 parts of the coating composition (D) obtained in (1-2) of Example 1 was coated with a polyurethane urea resin having a solid content of 20% (trade name: Rackskin U-35, Seiko Chemical Co., Ltd.). 50)
Was added and stirred uniformly to obtain a coating composition (M).

Example 5 To 100 parts of the coating composition (A) obtained in (1-1) of Example 1 was added 5 parts of a polyisocyanate (trade name: Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.). The mixture was uniformly stirred to obtain a coating composition (N).

Comparative Example 3 The coating composition obtained in Comparative Example 1
(I) 100 parts of polyisocyanate (trade name Coronate HL,
5 parts (manufactured by Nippon Polyurethane Industry Co., Ltd.) were added, and the mixture was stirred uniformly to obtain a coating composition (O).

Comparative Example 4 A reaction vessel equipped with a stirrer, a thermometer and a reflux condenser was charged with 80 parts of methyl methacrylate,
10 parts of 2,2-trifluoroethyl methacrylate, 5 parts of 2-hydroxyethyl methacrylate, 5 parts of 2-ethylhexyl methacrylate, 3 parts of di-tert-butyl peroxide and 100 parts of toluene were added, and the mixture was stirred under reflux for 8 hours. An acrylic copolymer was obtained, and 312 parts of toluene was added to the acrylic copolymer to obtain a coating composition (P) having a solid content of 20%.
I got The number average molecular weight in terms of polystyrene of this coating composition (P) as determined by GPC analysis was 13,000.

Each of the coating compositions obtained in Examples 1 to 5 and Comparative Examples 1 to 4 was coated on a polyvinyl chloride sheet for tarpaulin using a gravure printer at 100 mesh.
Coating was repeated and dried at 120 ° C. for 2 minutes to obtain a vinyl sheet having a coating of each coating composition formed on the surface.

Each of the vinyl sheets thus obtained was subjected to tests such as stain resistance and bending resistance, and the results are shown in Table 2.

[0050]

[Table 2]

The test using a stain-preventing contaminant was carried out as follows: 38.0% by weight of field soil (80 mesh after drying) Kaolin 17.0 〃 (commercially available reagent) Cement 17.0 〃 (commercially available) White carbon 17.0 〃 (commercially available) Carbon black 1.75 〃 (commercially available reagent) Ferric oxide 0.50 〃 (commercially available reagent first grade) Mineral oil 8.75 入 れ Put a contaminant consisting of a commercially available reagent, dioxyphthalate, into a plastic container and put each test piece (3
cm × 2.5cm), leave at 80 ° C for 30 minutes, and then
Shake twice, leave again at 80 ° C for 30 minutes, and shake 50 times.
Thereafter, the test piece was taken out, washed with water, and the degree of contamination on the test piece surface was visually determined.

As an outdoor exposure test for stain prevention, a test piece was hung outdoors and the stain prevention performance after 6 months was visually judged.

In the bending resistance test, a test piece was mounted on a bending tester and, after bending 10,000 times, the occurrence of cracks was visually judged.

The evaluations in Table 2 are as follows:…: no change;
や: slight change; △: noticeable change; x: change over the entire surface.

[0055]

As described above, since the coating composition of the present invention has a very large number average molecular weight of 100,000 to 1,000,000, it has an excellent stain-preventing effect even when it is formed into a thin film, and its aging with time. This is a practically significant effect that there is no decrease in the effect and that it has excellent bending resistance.

────────────────────────────────────────────────── (5) Continuation of the front page (51) Int.Cl. ⁶ identification code FI C09D 127: 12 133: 04 183: 04 127: 06) (56) References JP-A-60-238311 (JP, A) JP-A-60-238311 JP-A-63-61032 (JP, A) JP-A-3-258873 (JP, A) JP-A-48-4528 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C09D 133 / 12,133 / 16 C08F 20 / 14,20 / 22-20/24 C08F 220 / 14,220 / 22-220/24 C08L 33 / 12,33 / 16 C09K 3/00 112 C09K 3/18 102

Claims (2)

(57) [Claims] 1. (a) 60 to 90% by weight of methyl methacrylate, (b) 2 to 20% by weight of an α, β-ethylenically unsaturated monomer containing a fluorine element in the molecule, (c) other A number average molecular weight of 100,000 to 10 obtained by suspension polymerization of a monomer comprising 8 to 20% by weight of a copolymerizable monomer and a polymerization initiator.
A coating composition comprising 100,000 acrylic copolymers and an organic solvent. 2. (a) 60 to 90% by weight of methyl methacrylate, (b) 2 to 20% by weight of an α, β-ethylenically unsaturated monomer containing a fluorine element in the molecule, (c) other A number average molecular weight of 100,000 to 10 obtained by suspension polymerization of a monomer comprising 8 to 20% by weight of a copolymerizable monomer and a polymerization initiator.
100,000 acrylic copolymer and organic solvent, urethane resin
Fat, fluorine resin, acrylic resin, silicone resin,
A vinyl chloride resin or a copolymer of these resins
Or a mixture of the above acrylic copolymers as a mixed resin.
Coating composition consisting of less than or equal to solid content
Stuff.