JPH02194067A - Delustering agent - Google Patents

Abstract

PURPOSE:To improve design possibilities, weathering properties, solvent resistance, and adhesion properties by cutting an acrylic fiber having an acrylonitrile content and a fiber diameter each within a specified range and an active hydrogen group. CONSTITUTION:An acrylic fiber having an acrylonitrile content of 50wt.%, a fiber diameter of 100mum or less and an active hydrogen group is cut to a length of 3mm or less to give a delustering agent. 1-50pts. resulting delustering agent is compounded into 100pts. coating (solid base).

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a matting agent suitably used for paints and the like.

(Conventional technology and problems) In recent years, consumer tastes in paints have diversified, and one of these trends is a preference for medium to low-gloss, subdued-toned paint films over high-gloss ones. It has become.

Up until now, the methods for imparting a matte effect to paint are as follows:
Various solid additives have been added to paints as matting agents; for example, inorganic pigments such as calcium carbonate and silicon compounds, and inorganic materials such as glass fibers have been used. However, coating films using such solid additives tend to be flat, lack volume, and have poor design, and also suffer from poor coating film performance due to the incorporation of inorganic materials, resulting in increased coating hardness and inorganic materials. When the particle size of the material becomes larger than about 10 μ, wear resistance and scratch resistance tend to decrease due to the brittleness that is a characteristic of the inorganic material itself. has various drawbacks, such as poor adhesion with the organic resin matrix, and furthermore, the inorganic material itself does not have ductility, resulting in reduced processability of the coating film.

As a method to eliminate these drawbacks of inorganic materials, methods have been proposed to use thermoplastic organic polymer particles such as polyethylene and polypropylene polyester, but these matting agents have poor adhesion with paint. It has poor solvent resistance and melts to create a matte effect. There were drawbacks that reduced the

On the other hand, among organic polymer particles, acrylonitrile (
Although AN)-based polymer particles have various favorable properties such as excellent weather resistance and solvent resistance, and are desirable as matting agents, they cannot be used in conventional polymerization methods, such as aqueous precipitation. AN-based polymers obtained by methods such as polymerization, melt polymerization, or bulk polymerization have irregular particle shapes and sizes, or porous particles. It was difficult to obtain a uniform coating surface from paints containing .

For example, Japanese Patent Application Laid-Open No. 55-10626
No. 9, No. 57-126868, etc., uniform particles,
A method using an AN-based polymer of the same size has been proposed,
Although the matting effect is improved by such means, the production of the AN-based polymer spherical particles involves complicated operations and processes.

(Problem to be solved by the invention) In light of this situation, the inventors of the present invention have conducted intensive studies and found that an AN-based fiber with a very short fiber length containing a specific functional group can be used as a matting agent. The inventors have now discovered that it is possible to provide a matting agent that has excellent design properties, exhibits IIl# weatherability, solvent resistance, and adhesion without any production problems, and has thus arrived at the present invention.

That is, an object of the present invention is to provide an industrially advantageous matting agent that is excellent in design and has no practical problems such as weather resistance, solvent resistance, and adhesion.

(Means for Solving the Problems) The above-mentioned object of the present invention is to provide a polymer comprising a polymer containing 50% by weight or more of AN, containing a functional group having active hydrogen, and having a fiber diameter of 100 μm or less and a fiber length of 100 μm or less. This is achieved using 8H or less acrylic fiber.

The present invention will be explained in detail below.

The acrylic fiber used in the present invention must be made of a polymer containing 50% by weight or more of AN.
Satisfactory solvent resistance if below such lower limit, ##
It is not possible to achieve the desired purpose because it does not have a smooth texture and as a result, a matte effect cannot be obtained. Furthermore, the fiber diameter of the fiber is determined depending on the thickness of the coating film, but is less than looμ,
The fiber length is preferably 40μ or less, and the fiber length is 8n or less, preferably 1In1 or less. If it exceeds this upper limit, it may be used as a matting agent to disperse the coating into the paint or to make the coating film uniform during application. Unable to achieve the intended purpose. .

In this list, the acrylic fiber must contain at least one type of functional group having active hydrogen, such as a hydroxyl group, a carboxyl group, an amide group, an amino group, a sulfonic acid group, and a sulfuric acid group. The introduction improves the adhesion with the paint matrix resin. In addition, the content of such functional groups is 0.2 to 0.2 to the weight of the acrylic fiber.
lO%, preferably within the range of 0.6 to 5%,
If the lower limit is exceeded, the effect of improving adhesion is small;
Moreover, when the upper limit is exceeded, the water resistance of the coating film decreases.

The method of introducing such a functional group is not limited, and there are known methods such as copolymerizing a monomer containing a desired functional group, introducing it as a catalyst terminal, and modifying acrylic fiber (hydrolysis, reduction, etc.). may be adopted as appropriate, and some of these means may be combined.

In addition, the cross-sectional shape of Acrylic IIIR, 1m can be arbitrarily adopted such as round, irregular shape, etc., but irregular cross-sectional shapes such as flat, eyebrow shape, triangle, square, Y-shape, cross, 0-shape, etc., among others, flat,
Eyebrow-shaped and triangular shapes are desirable in terms of the design of the coating film (glitter), etc.

As mentioned above, the method for producing such a matting agent is not limited in any way as long as fibers satisfying the desired AN content, functional group content, fiber diameter, and fiber length can be obtained; It can be obtained by cutting short or long acrylic fibers having a desired fiber length within a desired range. In addition, when introducing a functional group by modifying the acrylic fiber, it may be carried out either before or after cutting.

It is important that fusion does not occur between the fibers when cutting (when multiple fibers are pressed together at the cut surface due to the pressure during cutting), and if fusion occurs, the fluidity of the paint will be reduced. worsened,
It is not possible to obtain a uniform coating film.

In addition, from the viewpoint of applicability (dispersibility into paint), it is desirable to attach an oil to the fiber surface.

The type of oil agent cannot be determined unambiguously because it needs to be changed depending on the type of matrix resin, dispersion medium, or solvent in the paint, but for water-based paints, for example, nonionic, anionic, Hydrophilic oils such as cationic oils are preferred, and for drainage paints, hydrophobic oils such as fluorine-based and silicone-based oils are preferred. The amount of oil attached is generally within the range of 0.1 to 3% based on the weight of the fiber.

Note that the oiling step may be performed either before or after cutting the fibers into very short lengths, but it is preferable to apply the oil before cutting in terms of operability and avoidance of interfiber fusion during cutting.

In particular, in order to further improve adhesion, coating properties, etc., it is desirable that the fiber length be 0.5 Iff or less, preferably 0.8 m or less; You can especially get it.

Furthermore, depending on the final use of the paint, the paint film may be required to have functions such as flame retardancy or noncombustibility, antistatic or conductive properties, moisture and water absorption properties, etc. In such cases, these properties as well as the above-mentioned properties may be required. Acrylic fibers having these functions can be appropriately used as a matting agent.

The matting agent of the present invention can be added to paint by the usual methods, such as adding it during paint production and kneading, or dispersing it in a paint diluent in advance and adding this paint diluent to the paint. Various methods can be adopted, such as a method of adding.

At this time, the blending ratio of the matting agent to the paint is 1
00 parts to 1 to 50 parts of matting agent, preferably 2 to 80 parts
Preferably within the range.

If the lower limit of this range is exceeded, a sufficient matting effect cannot be achieved, and if the upper limit is exceeded,
The intended purpose of uniformly dispersing the matting agent in the paint cannot be achieved.

There are no restrictions on the paints that use matting agents, such as acrylic,
Non-aqueous paints such as melamine alkyd, epoxy, phenol, polyester, silicone acrylic, and vinyl paints, or water-based paints are used.

(Effect of the invention) In this way, a matting agent that has excellent weatherability, solvent resistance, adhesion, and dispersibility in paint, as well as a rich design and a rich volume, can be produced without requiring special equipment or complicated operations. A noteworthy effect of the present invention is that it has been able to provide industrial advantages without any problems.

(Example) The present invention will be explained in more detail with reference to Examples below.
The scope of the present invention is not limited by the description of these Examples. The weight ratio shown in the examples is based on weight unless otherwise specified.

Note that solvent resistance, gloss, weather resistance, adhesion, design, and dispersibility were measured as follows.

(1) After drying the fibers as rm solvent-based matting agent, Kijirol/Butanol/Cyclohexane/Gutylcarpitol = 40
/l 5/l Immerse in 6/80 mixed solvent and heat at 50℃ x 8
After storage for 00 hours, the weight loss rate was measured.

12) Heating residue 5 whose main component is a glossy acrylic acid ester polymer
A test paint was prepared by uniformly dispersing a predetermined amount of a matting agent in a 0% water-based emulsion paint. Apply the paint to a plate thickness of 0.86
JFF's regular phosphate-treated galvanized steel plate is roll-coated with epoxy paint as a primer to a thickness of approximately 5μ, then baked and then roll-coated to a thickness of approximately 25μ to produce a coated steel plate. did.

The gloss of this steel plate was measured by 60 degree specular reflectance (maximum).

(8) A coated steel plate was prepared in the same manner as above except that a polyester solvent paint was used instead of the water-based emulsion paint of a weather-resistant acrylic ester polymer, and after 1000 hours of sunshine weather meter testing, the steel plate before the test was The color difference △ was measured using Hitachi's Color Analyzer Model 807 using a standard plate.
E was measured.

(4) Design The glittering appearance of the coated steel sheets prepared in the same manner as in the above weather resistance measurement was visually evaluated.

○: Glittering feeling △: Slightly glistening feeling X: No glittering feeling 5) Adhesion A coated steel plate prepared in the same manner as the above 111it weatherability measurement was wound around a tip bar with a radius of 5H to peel off the film. The condition was observed with a 10x magnifying glass.

○: No peeling of the film. Δ: Slight peeling. X: Significant peeling.

○: Woven fibers are uniformly distributed △: Some woven fiber clumping is observed ×: Examples where fiber clumping is significantly observed l As the monomer to be copolymerized with AN, methacrylic acid, acrylamide, or Using methyl acrylate, five types of AN-based polymers were prepared by varying the type and copolymerization amount of the monomer, and the polymers were spun according to a conventional method to obtain round-section acrylic fibers (fiber diameter 25.u, nonionic oil adhesion amount 0
．． 7%) was prepared and then cut into fiber lengths of 0.15 mm using a Matsushita Seiki cutter to obtain 5 types of test fibers (each having a solvent resistance of 0.3%).

The results of evaluating various performances (adding 20% of the test fiber to the pure content of the paint) are shown in Table 1 below.

Table 1 From the above table, the products of the present invention (No. 1) containing a predetermined functional group.
It can be clearly understood that through 4), the adhesion is improved while maintaining other properties.

Example 2 Eight types of test fibers were prepared in the same manner as in Example INO, 1 except that the cross-sectional shape of the fibers was changed as shown in Table 2 below.

The design evaluation results are also listed in Table 2.

Table 2 A fiber was prepared.

Table 8 shows the evaluation results of dispersibility.

8th Table above, I recommend the present invention! Apply a layer of oil within range A (
It is understood that dispersibility is improved by Na, lO~11).

As is clear from the table above, both round and irregular shapes are better in terms of giving the paint film a sense of design (glitter).

Example 8

Claims (1)

[Claims] A matting agent made of an acrylic fiber made of a polymer containing 50% by weight or more of acrylonitrile, containing a functional group having active hydrogen, and having a fiber diameter of 100 μm or less and a fiber length of 3 mm or less.