JP2001348524A - Resin composition for coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition for coating capable of carrying out coating excellent in scuff resistance with low glossiness on polypropylene. SOLUTION: This composition for coating is characterized as comprising (A) a modified chlorinated polyolefin prepared by copolymerizing a chlorinated polyolefin with an acrylic monomer and styrene and containing the styrene in an amount of 8-24 wt.% based on 100 wt.% of the modified chlorinated polyolefin, (B) the chlorinated polyolefin and (C) acrylic beads having 3-15 μm average particle diameter in (80:20) to (84:16) weight ratio of the components (A):(B) with the content of the component (C) within the range of 25.5-45.5 wt.% based on 100 wt.% of the sum total of the components (A), (B) and (C).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a resin composition for a paint.

[0002]

2. Description of the Related Art In interior painting of automobiles, low gloss paints are sometimes used for the purpose of improving texture. Polyolefin-based polymers, for example, polypropylene, which have high performance such as cost and recyclability, may be used as materials for automobile interior materials. Polyolefin-based polymers have low polarity and high crystallinity, and therefore have extremely poor coatability. Therefore, in the conventional low gloss paint, talc and silica are mixed in a mixture of a chlorinated polyolefin modified acrylic resin and a chlorinated polyolefin resin.

[0003]

However, in order to achieve low gloss, there is an inconvenience that the scratch resistance of the coated surface after coating is reduced.

[0004] Accordingly, an object of the present invention is to provide a coating composition capable of coating with excellent scratch resistance.

[0005]

Means for Solving the Problems For the purpose of solving the above problems, the present inventors have conducted intensive studies and found that the use of acrylic beads instead of talc or silica improves the scratch resistance of the painted surface. I thought. Here, acrylic beads improve the scratch resistance of the painted surface, but when used in low-polarity polymers such as polypropylene (PP), which are widely used in automobile interiors, the oil and fat resistance is reduced. It has been conceived that low polarity styrene is introduced to lower the polarity of the entire coating composition and to improve the affinity with PP.

That is, the coating composition of the present invention for solving the above-mentioned problems is a modified chlorinated polyolefin obtained by copolymerizing (A) a chlorinated polyolefin with an acrylic monomer and styrene, 10
(B) chlorinated polyolefin containing (B) chlorinated polyolefin, and (C) acrylic beads having an average particle diameter of 3 to 15 μm with respect to 0% by weight, The weight ratio of A) :( B) is 80: 2
0 to 84:16, and the content of (C) is 25.5 based on 100% by weight of the total of (A), (B) and (C).
-45.5% by weight.

As described above, by containing the modified chlorinated polyolefin obtained by copolymerizing the acrylic beads and the acrylic monomer, the scratch resistance of the painted surface is improved, and the modified chlorinated polyolefin obtained by copolymerizing styrene is contained. By doing so, it is possible to provide a resin composition for coatings in which the affinity for PP and the like is improved.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The coating composition of the present invention will be described below in detail.

The coating composition of the present embodiment contains (A) a modified chlorinated polyolefin, (B) a chlorinated polyolefin, and (C) acrylic beads.

(A) The modified chlorinated polyolefin is a polymer in which some of the hydrogen atoms of the polyolefin are replaced by chlorine atoms and grafted with a copolymer of an acrylic monomer and styrene. The site of the polyolefin to which the acrylic monomer and styrene are grafted is not particularly limited. The copolymerization of the acrylic monomer and styrene may be regular such as block copolymerization or irregular such as random copolymerization.

The polyolefin serving as the skeleton is not particularly limited. For example, polyethylene, polypropylene, ethylene-propylene copolymer which is a polymer of chain hydrocarbon C _n H _2n generally referred to as ethylene, propylene, butene, etc. , Ethylene-propylene-diene copolymer, styrene-butadiene-isoprene copolymer, and hydrogenated products thereof.

The purpose of introducing the acrylic monomer is to increase the solubility of the paint. The ratio of introducing the acrylic monomer is 1 for the entire modified chlorinated polyolefin.
When the acrylic monomer is 50% by weight,
It is preferred to contain 90% by weight. If the ratio is out of this range, the hardness of the coating film decreases, or the stability when dissolved in a solvent is poor.

The introduction of styrene is because styrene is low in polarity, high in Tg, low in cost, and easily copolymerized with acrylic monomers. The ratio of introducing styrene is preferably 8 to 24% by weight of styrene based on 100% by weight of the entire modified chlorinated polyolefin. If the ratio is outside this range, the affinity with PP decreases.

Although the molecular weight of the modified chlorinated polyolefin is not particularly limited, if it is too large, the workability at the time of coating is remarkably reduced due to an increase in viscosity accompanying an increase in the molecular weight, and the finished state after the coating treatment is not uniform. Finished,
On the other hand, if it is too small, the coating properties after coating will be poor in durability against solvents and chemicals and light resistance.
It is preferably about 50,000 to 200,000 (in terms of styrene). The ratio of chlorination is preferably about 25 to 35% by weight when the portion excluding the acrylic monomer and the portion derived from styrene is 100% by weight.
It is preferable from the viewpoint of increasing the adhesion to P. If it is lower than this, the stability in a general solvent is inferior, and if it is higher than this, the adhesion to PP becomes low.

An example of a method for producing a modified chlorinated polyolefin is as follows. A chlorinated polyolefin is dissolved in a suitable solvent, and while heating, an acrylic monomer in which a suitable polymerization initiator is dissolved is mixed with styrene. There is a method of dropping the mixture. The modified chlorinated polyolefin may partially include a copolymer of styrene and an acrylic monomer not grafted to the polyolefin portion.

The acrylic monomer is not particularly limited. For example, methyl (meth) acrylate, ethyl (meth) acrylate, n- or i-propyl (meth) acrylate, n-, i-, t-, or s
ec-butyl (meth) acrylate, pentyl (meth)
(Meth) acrylates having a hydrocarbon substituent such as an alkyl (meth) acrylate such as acrylate, lauryl (meth) acrylate, dodecyl (meth) acrylate, or a cycloalkyl (meth) acrylate such as cyclohexyl (meth) acrylate; Ethylenically unsaturated esters such as acrylonitrile and methacrylonitrile; N-alkoxy-substituted amides such as N-methoxymethylacrylamide, N-ethoxymethylacrylamide and N-butoxymethylacrylamide; dimethylaminoethyl (meth) acrylate, diethylaminoethyl Ethylenically unsaturated basic monomers such as (meth) acrylate; 2-hydroxyethyl (meth) acrylate,
Monomers having a hydroxyalkyl group such as 2-hydroxypropyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate; ring-opening adduct of γ-butyrolactone to 2-hydroxyethyl methacrylate;
-Ring-opening adduct of ε-caprolactone to hydroxyethyl acrylate; ring-opening adduct of ethylene oxide to methacrylic acid; ring-opening adduct of propylene oxide to methacrylic acid; glycidyl (meth) acrylate, methyl glycidyl (meth) Epoxy group-containing monomers such as acrylate and 3,4-epoxycyclohexyl (meth) acrylate can be used, and they can be used alone or as a mixture of two or more.

(B) The chlorinated polyolefin is obtained by substituting a part of hydrogen atoms of a polyolefin comprising an aliphatic hydrocarbon with chlorine, and is not particularly limited. Examples thereof include polyethylene, polypropylene, and ethylene-propylene copolymer. A copolymer, an ethylene-propylene-diene copolymer, a styrene-butadiene-isoprene copolymer, and a hydrogenated product thereof. The substitution ratio of chlorine is preferably about 25 to 35% by weight when the whole chlorinated polyolefin is 100% by weight. P
It is preferable from the viewpoint of increasing the adhesion to P. If it is lower than this, the stability in a general solvent is inferior, and if it is higher than this, the adhesion to PP becomes low. The molecular weight of the chlorinated polyolefin is not particularly limited.
A range of about 20,000 to 100,000 (in terms of styrene) is preferable. If the molecular weight is too low, adhesion to PP material, which is considered to be caused by a decrease in cohesive strength, is reduced. If the molecular weight is too high, it is difficult to obtain a uniform finished state due to a reduction in coating workability. is there.

(A) Modified chlorinated polyolefin and (B)
The mixing ratio with the chlorinated polyolefin is 80:20 to 84:
It is preferable to be within the range of 16. (A) If a large amount of the modified chlorinated polyolefin is added, the scratch resistance is improved, but the affinity for PP and the like is reduced, and the oil and fat resistance is poor. Further, when the blending amount of the chlorinated polyolefin (B) is increased, the oil and fat resistance is improved, but the hardness is reduced and the scratch resistance is poor.

(C) The acrylic beads have an average particle size of 3 to 1
5 μm particles made of an acrylic resin. By including acrylic beads, the surface of the coating film can be made matt. The acrylic resin is not particularly limited, but is, for example, a resin obtained by polymerizing a monomer having the above-mentioned acrylic monomer as a main component. The acrylic resin is used because the hardness of the acrylic resin is high and the resin is hardly deformed, and the affinity of the coating film is high because the main component of the coating film contains the acrylic resin. When the average particle size is out of the range of 3 to 15 μm, the appearance and the feel of the painted surface are inferior. If the particle size is smaller than 3 μm, the matte effect on the surface of the painted surface is inferior, and if the matte effect is to be increased, a large amount of acrylic beads must be contained, so that the feel is also poor. On the other hand, if the particle size is larger than 15 μm, the acrylic beads protrude from the surface of the painted surface, so that the tactile sensation deteriorates. The shape of the acrylic beads is not particularly limited, but a true spherical shape is preferable from the viewpoint of tactile sensation.

Acrylic beads can be prepared by subjecting an acrylic monomer or the like to suspension polymerization, emulsion polymerization, or the like, or can be prepared by pulverizing an acrylic resin mass with a ball mill or the like. .

The mixing ratio of the acrylic beads is 25.5 to 45.5 when the total solid content of the paint is 100% by weight.
It is preferable to set the weight%. If the amount is less than this, the matte effect of the painted surface is inferior, and if the amount is more than this, the acrylic beads are oriented on the surface of the coating film, so that the feel is deteriorated.

The resin composition for coatings of the present invention may be used in a suitable solvent, for example, a hydrocarbon solvent such as toluene and xylene, a ketone solvent such as methyl ethyl ketone and methyl isobutyl ketone, and an ester solvent such as ethyl acetate and butyl acetate. , Dioxane, ethylene glycol diethyl ether, and other ether-based solvents alone or in a mixed solvent. The dissolution concentration is 1
About 0 to 60% by weight is preferable. Further, when the resin composition for coating of the present invention is used as a coating, if necessary, inorganic pigments such as titanium white and carbon black, phthalocyanine pigments, organic pigments such as azo pigments, plasticizers, Various additives such as a resin for strengthening a coating film, a dispersant, a coating surface modifier, an ultraviolet absorber, an ultraviolet stabilizer, an antioxidant, and a crosslinking reaction accelerator can be included.

As a method of applying a coating material dissolved in a solvent to an object to be coated, known devices and methods such as air spray, airless spray, electrostatic coating machine, dipping, roll coating machine, and brush coating are employed. it can.

[0024]

EXAMPLES <Synthesis of Modified Chlorinated Polyolefin> (Synthesis Example 1) 100 parts by weight of chlorinated polyolefin (Nippon Paper Industries Co., Ltd. Supercron 822 (diluted product of chlorinated polyolefin resin in 20% toluene)) was placed in a flask. While stirring 70 parts by weight of toluene at 100 ° C. under a nitrogen atmosphere, styrene and methyl methacrylate (MM
A) a mixture of (A) and (11.4: 88.6).
A solution obtained by dissolving 0.95 parts by weight of azobisisobutyronitrile (AIBN) as a polymerization initiator in 6.5 parts by weight was added dropwise. The mixture of the monomer and the initiator was added dropwise over 2 hours, while keeping the temperature in the flask at 100 ° C. 0.3, 30, 60 and 90 minutes after the end of dropping, respectively.
A part by weight of AIBN was added, and the reaction was terminated by keeping the temperature at 100 ° C. for 3 hours after the last addition.

(Synthesis Example 2) Styrene and MMA of Synthesis Example 1
A mixture obtained by mixing styrene and MMA at a ratio of 23:77 was used as a mixture with the above, and 0.95 part by weight of AIBN as a polymerization initiator dissolved in 46.5 parts by weight of the mixture was dropped. Synthesized modified chlorinated polyolefin A2 in the same manner as in Synthesis Example 1.

(Synthesis Example 3) Styrene and MMA of Synthesis Example 1
As a mixture with styrene and MMA at 34.4: 6.
Using a mixture mixed at a ratio of 5.6, the mixture 4
A modified chlorinated polyolefin A3 was synthesized in the same manner as in Synthesis Example 1 except that 0.95 part by weight of AIBN as a polymerization initiator was added dropwise to 6.5 parts by weight.

(Synthesis Example 4) Styrene and MMA of Synthesis Example 1
85.8: 1 as a mixture with styrene and MMA.
A mixture mixed at a ratio of 4.2 was used, and the mixture 4
A modified chlorinated polyolefin A4 was synthesized in the same manner as in Synthesis Example 1 except that 0.95 part by weight of AIBN as a polymerization initiator was added dropwise to 6.5 parts by weight.

<Manufacture of Acrylic Beads> Shin-Etsu Chemical Co., Ltd.
Water-soluble cellulose ether manufactured by Metrolose 60S
100 parts by weight of an aqueous solution of 0-50% sodium dodecylbenzenesulfonate added to a 3% aqueous solution of H-50 was prepared, and normal butyl methacrylate: MMA: ethylene glycol dimethacrylate: peroxide manufactured by Kayaku Aguso Co., Ltd. , Trade name Trigonox 23-C70 = 50: 28:
15 parts by weight of a mixture of a 20: 2 monomer and an initiator was added dropwise at room temperature for 30 minutes with vigorous stirring.

The obtained suspension was heated to 60 ° C. with vigorous stirring, and reacted for 6 hours.

After completion of the reaction, the obtained resin particles were sufficiently washed with water by decantation, and then dried. After drying, pulverize the obtained resin particle cake,
Classification was performed to obtain resin particles having a desired average particle diameter. In addition, the adjustment of the average particle diameter serving as the center of the reaction product was adjusted by the content of sodium dodecylbenzenesulfonate in the dispersion medium and the stirring speed.

<Preparation of Test Samples> The coating materials of the respective Examples and Comparative Examples shown below were applied to polypropylene plates to obtain test samples of the respective Examples and Comparative Examples.

(Example 1) Modified chlorinated polyolefin A
1, 80 parts by weight, 20 parts by weight of chlorinated polyolefin (Supercron E: Nippon Paper Industries Co., Ltd.), and acrylic beads (particle size 7 μm) in PWC (pigment weight per cent).
t) was 30%, and the mixture was dissolved in a solvent (a mixed solvent consisting of toluene / xylene = 50/50) so as to be 20% by weight based on the whole coating material. Paint.

(Example 2) Modified chlorinated polyolefin A
1 and 84 parts by weight, chlorinated polyolefin and 16 parts by weight, and acrylic beads (particle diameter 7 μm) were mixed so that the PWC became 30%.
Solvent (toluene / xylene = 50 /
50) was used as a paint of Example 2.

Example 3 Modified chlorinated polyolefin A
3 and 80 parts by weight of chlorinated polyolefin, 20 parts by weight of chlorinated polyolefin, and acrylic beads (particle diameter: 7 μm) so that the PWC becomes 30%.
Solvent (toluene / xylene = 50 /
50) was used as the coating material of Example 3.

(Example 4) Modified chlorinated polyolefin A
2 and 80 parts by weight of chlorinated polyolefin, and 20 parts by weight of chlorinated polyolefin, and acrylic beads (particle size: 3 μm) so that the PWC becomes 25%.
Solvent (toluene / xylene = 50 /
50) was used as the coating material of Example 4.

(Example 5) Modified chlorinated polyolefin A
2, 80 parts by weight, chlorinated polyolefin, 20 parts by weight, and acrylic beads (particle size: 15 μm) having a PWC of 45%
And the mixture is mixed with 2 parts of the total paint.
Solvent (toluene / xylene = 50) so as to be 0% by weight.
/ 50) in Example 5.
Paint.

Comparative Example 1 Modified Chlorinated Polyolefin A
1 and 70 parts by weight of chlorinated polyolefin, and 30 parts by weight of chlorinated polyolefin, and acrylic beads (particle diameter: 7 μm) so that the PWC becomes 30%.
Solvent (toluene / xylene = 50 /
50) was used as the coating material of Comparative Example 1.

Comparative Example 2 Modified Chlorinated Polyolefin A
1 and 86 parts by weight of chlorinated polyolefin, 14 parts by weight of chlorinated polyolefin, and acrylic beads (particle diameter: 7 μm) so that the PWC becomes 30%. Solvent (a mixed solvent consisting of toluene / xylene = 50/50) so as to be 20% by weight
Was used as a coating material of Comparative Example 2.

Comparative Example 3 Modified Chlorinated Polyolefin A
4 was mixed with 80 parts by weight of chlorinated polyolefin, 20 parts by weight of chlorinated polyolefin, and acrylic beads (particle diameter: 7 μm) so that the PWC became 30%.
Solvent (toluene / xylene = 50 /
50) was used as a paint of Comparative Example 3.

Comparative Example 4 Modified Chlorinated Polyolefin A
2, 80 parts by weight of chlorinated polyolefin, 20 parts by weight of chlorinated polyolefin, silica (particle size: 1 μm, TS-100: Degussa Co., Ltd.) with 15% PWC, and acrylic beads (particle size: 7 μm).
m) was mixed so as to have a PWC of 30%, and the mixture was dissolved in a solvent (a mixed solvent consisting of toluene / xylene = 50/50) so that the mixture became 20% by weight based on the entire coating composition. The paint of Example 4 was used.

Comparative Example 5 Modified Chlorinated Polyolefin A
2 and 80 parts by weight of chlorinated polyolefin, and 20 parts by weight of chlorinated polyolefin, and acrylic beads (particle diameter: 20 μm) so that the PWC becomes 5%.
Solvent (toluene / xylene = 50 /
50) was used as the coating material of Comparative Example 5.

Comparative Example 6 Modified Chlorinated Polyolefin A
2 and 80 parts by weight of chlorinated polyolefin, and 20 parts by weight of chlorinated polyolefin, and acrylic beads (particle size: 2 μm) so that the PWC becomes 45%.
Solvent (toluene / xylene = 50 /
50) was used as a coating material of Comparative Example 6.

<Oil and Fat Soil Resistance Test> ² g of tallow per 100 cm ² was placed on the test surface of a test sample left at room temperature for 48 hours.
Was applied. In order to maintain a constant amount of tallow volatilized during the test, a cloth (nel) slightly smaller than the test piece was placed, and this was left for 1 week in an electric furnace at 80 ° C. and in an atmosphere without forced convection. The test surface was cleaned using a neutral detergent.

A dry cloth friction test and an adhesion test were performed on the test sample subjected to the above treatment. In the dry cloth friction test, five pieces of gauze (Japanese Pharmacopoeia) were fixed on the surface where the friction element was in contact with the sample, and a load (49.04 kPa) was applied to the friction element.
The reciprocating friction was performed 200 times with a stroke of 100 mm. After the test, those without exposure and peeling of the coating film were judged as acceptable. The adhesion test is performed by cutting the coating film on the test surface of the test sample into a cross so that the length of the cut portion is 2 cm, and then applying an adhesive tape (Cellotape: Nichiban Co., Ltd.) to the cut portion, and applying an adhesive tape. Was passed when there was no peeling when peeling. When both of the friction test and the adhesion test passed, the grease resistance test was passed.

<Scratch Resistance Test> Five pieces of gauze (Japanese Pharmacopoeia) are stacked and fixed on the surface where the friction element comes into contact with the sample. A load (49.04 kPa) is applied to the friction element, and a stroke 1
Reciprocating friction was performed 20 times at 00 mm. 60 ° before and after the test
The gloss was measured, and when the change in gloss was within 150%, it was judged as passing. The gloss was measured by a conventional method using a specular gloss meter. The gloss change was determined by the following equation, and 150% or less was regarded as acceptable.

(Gloss change (%)) = ｛(gloss after test)
-(Gloss before test) / (gloss before test) x 100 <Tactile test> A sensory test was performed on the touch of the test surface of the test sample. The result was a two-level evaluation of good and bad.

<Results> The results of each test are also shown in Table 1.

[0048]

[Table 1]

As is clear from Table 1, the test samples of each example passed all the tests. In contrast, the test sample of Comparative Example 1 has a high ratio of chlorinated polyolefin to modified chlorinated polyolefin,
The result was that the hardness of the coating film was low and the scratch resistance was poor. In contrast to Comparative Example 1, the test sample of Comparative Example 2 had a low ratio of the chlorinated polyolefin to the modified chlorinated polyolefin, resulting in poor adhesion of the coating film to polypropylene, and poor oil and fat stain resistance. It became. Since the test sample of Comparative Example 3 had a high styrene content, the coating film was inferior in adhesion to polypropylene and poor in grease stain resistance.

The test sample of Comparative Example 4 contained silica having a lower hardness than the acrylic resin, resulting in noticeable scratches on the coating film surface and poor scratch resistance. The test sample of Comparative Example 5 was inferior to the tactile test because the beads contained in the acrylic beads had a large particle size and the beads caught out of the coating film surface. In contrast to Comparative Example 5, the test sample of Comparative Example 6 requires a large amount of acrylic beads to obtain a coated surface having the same matte because the particle size of the acrylic beads is small. As a result of the large orientation of the acrylic beads, the result was inferior to the tactile test.

[0051]

According to the present invention, there is provided an effect of providing a coating composition capable of coating with excellent scratch resistance without sacrificing oil resistance and tactile sensation.

Continued on the front page. (72) Inventor Keizo Okabe 1-18-1 Takada, Toshima-ku, Tokyo Origin Electric Co., Ltd. (72) Takeharu Ueda 1-1-18-1 Takada, Toshima-ku, Tokyo Origin Electric Co., Ltd. In-house F term (reference) 4J038 CA042 CA132 CB022 CB082 CB102 CB122 CB172 CC042 CG032 CG142 CP051 GA06 GA12 KA08 KA20 NA01 NA11 NA19

Claims (3)

[Claims] 1. A modified chlorinated polyolefin obtained by copolymerizing (A) a chlorinated polyolefin with an acrylic monomer and styrene.
A modified chlorinated polyolefin containing 8 to 24% by weight of the styrene with respect to 0% by weight, (B) a chlorinated polyolefin, and (C) acrylic beads having an average particle size of 3 to 15 μm; The weight ratio of A) :( B) is from 80:20 to 84:16, and the content of (C) is a total of 10 of (A), (B), and (C).
A resin composition for a paint, wherein the content is in the range of 25.5 to 45.5% by weight based on 0% by weight. 2. The coating resin composition according to claim 1, wherein the chlorinated polyolefin of (A) and (B) has a chlorine content of 25 to 35% by weight. 3. The modified chlorinated polyolefin of (A) contains 50 to 90% by weight of the acrylic monomer based on 100 parts by weight of the modified chlorinated polyolefin. Paint resin composition.