JP2004300435A - Aqueous coating material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve an aqueous coating material containing fibrous material by enhancing dispersibility of fibers in the coating material, suppressing bubble attaching due to the mixing of the fibers and improving reduction in extension of a formed coating film caused by mixing the fibers. <P>SOLUTION: This aqueous coating material comprises a binder, a particulate material and fibers as essential components, and contains 0.01-10 wt.% of the fibers per total coating material, wherein the fiber is cellulose acetate fiber with 0.01-10mm length. Waste tobacco filters are preferable as the cellulose acetate fibers. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a novel aqueous coating material.

Conventionally, as a coating material applied to a building, a civil engineering structure, or the like, an aqueous coating material capable of forming a thick film of about 1 to 10 mm is used. Specifically, various coating materials such as lysine, stucco, spray tiles, and single-layer elastic coating materials can be used. These are coating materials that can impart various uneven patterns to the formed coating film. Further, as a water-based coating material for repairing irregularities, burrows, cracks, and the like of a base, putties, fillers, surfacers, and the like can be given.
In such a thick-film type water-based coating material, various fibers such as pulp fiber, acrylic fiber, polyester fiber, nylon fiber, carbon fiber, and the like are usually mixed for the purpose of improving the strength of the formed coating film, preventing cracking, and the like. I have.

For example, Japanese Patent Application Laid-Open No. 52-136229 (Patent Document 1) discloses that, based on 100 parts by weight of a synthetic resin emulsion, 10 to 150 parts by weight of an inorganic filler and 1 to 50 parts by weight of a fiber such as pulp or polyethylene are mixed. An aqueous coating material for forming a concavo-convex pattern is described.
Japanese Patent Application Laid-Open No. 8-134378 (Patent Document 2) describes a water-based coating material for preparing a base material containing a synthetic resin emulsion, an extender, a thickener, and fibers such as pulp as main components.

However, in the case of the water-based coating materials as described in the above-mentioned patent documents, the fibers may not be uniformly dispersed when mixed. There is also a problem that foaming is likely to occur in the coating material in the dispersion step after fiber mixing. Such a problem may adversely affect the finished appearance of the formed coating film.
Further, in the conventional water-based coating material, although the strength and the crack prevention property of the formed coating film are improved by mixing the fibers, there is also a problem that the elongation of the formed coating film is significantly reduced.

JP-A-52-136229 JP-A-8-134378

The present invention has been made in view of such circumstances, and has as its object to solve the following problems in aqueous coating materials containing fibers.
(1) To increase the dispersibility of the fibers in the aqueous coating material.
(2) Suppress foaming due to fiber mixing.
(3) Improve decrease in elongation of the formed coating film due to fiber mixing.

  As a result of intensive studies, the present inventors have found that the above problem can be solved by mixing cellulose acetate fibers having a fiber length of 0.01 to 10 mm into an aqueous coating material.

That is, the present invention relates to an aqueous coating material having the following characteristics.
1. An aqueous coating material containing a binder, a granular material, and fibers as essential components and containing 0.01 to 10% by weight of fibers based on the entire coating material, wherein the fibers are acetic acid having a fiber length of 0.01 to 10 mm. An aqueous coating material containing cellulose fibers.
2. The cellulose acetate fiber is a waste material of a tobacco filter. A water-based coating material as described above.
3. 1. The binder is a cross-linkable binder having a reactive functional group. Or 2. 2. The aqueous coating material according to 1.

ADVANTAGE OF THE INVENTION According to this invention, the dispersibility of the fiber in an aqueous coating material can be improved. Also, foaming in the fiber dispersion step can be suppressed.
Furthermore, in the formed coating film, the strength improvement effect, crack prevention effect, etc., which are equal to or higher than those of the conventional product, can be obtained, and the decrease in elongation seen in the conventional product can be improved.
The use of waste tobacco filter as cellulose acetate fiber can greatly contribute to resource recycling.

  Hereinafter, the present invention will be described in detail based on its best mode.

  The aqueous coating material of the present invention contains a binder, a granular material, and a fiber as essential components.

  Among these, a water-soluble, water-dispersible, solvent-soluble, solvent-dispersed, and solventless organic binder and / or inorganic binder can be used as the binder. Examples of the organic binder include acrylic resin, vinyl chloride resin, vinyl acetate resin, polyurethane resin, acrylic silicone resin, fluororesin, epoxy resin, polyester resin, melamine resin, alkyd resin and the like. Examples of the inorganic binder include, for example, Portland cement, alumina cement, ultra-hard cement, expanded cement, acid phosphate cement, silica cement, lime mixed cement, blast furnace cement, fly ash cement, keince cement, magnesia cement, dolomite, Hydraulic lime, gypsum, water glass and the like can be mentioned. These can be used alone or in combination of two or more.

The binder of the present invention is not particularly limited, such as a crosslinked type and a non-crosslinked type, but a crosslinked type binder having a reactive functional group is preferably used. The use of a cross-linking binder is preferable because it improves the strength of the formed coating film and provides a coating film having excellent low-stainability and weather resistance.
Examples of such a combination of reactive functional groups include, for example, epoxy-amine, polyol-isocyanate, carboxyl-epoxy, carboxyl-metal ion, carboxyl-carbodiimide, carboxyl-oxazoline, carbonyl-hydrazide, hydrolyzable silyl groups and the like. Is mentioned. Among these, a combination of carboxyl-epoxy, carboxyl-metal ion, carboxyl-carbodiimide, carboxyl-oxazoline, carbonyl-hydrazide, hydrolyzable silyl groups, and the like are preferably used, and a combination of carbonyl-hydrazide is particularly preferable.

  The mixing ratio of the binder is generally about 5 to 95% by weight, preferably about 10 to 80% by weight, based on the whole coating material.

Examples of powders include inorganic color pigments such as titanium oxide, zinc oxide, carbon black, ferric oxide (red iron oxide), yellow iron oxide, ultramarine, cobalt green, etc., azo-based, naphthol-based, pyrazolone-based, and anthraquinone. , Perylene-based, quinacridone-based, disazo-based, isoindolinone-based, benzimidazole-based, phthalocyanine-based, and quinophthalone-based organic coloring pigments; heavy calcium carbonate, light calcium carbonate, kaolin, clay, clay, china clay, Body pigments such as diatomaceous earth, talc, barite powder, precipitated barium sulfate and barium carbonate; silica sand, gravel, cold water stone, glass beads, resin beads, metal particles, or rock, glass, ceramics, sintered bodies, concrete, mortar, Aggregates such as crushed products such as plastics and rubbers are included. These can be used alone or in combination of two or more.
The mixing ratio of the powder is usually about 5 to 95% by weight, preferably about 20 to 90% by weight, based on the whole coating material.

In the present invention, a cellulose acetate fiber having a fiber length of 0.01 to 10 mm is used as the fiber. This cellulose acetate fiber is easily compatible with the aqueous coating material and has excellent dispersibility. In addition, foaming is less likely to occur as compared with conventionally used fibers. Furthermore, in the formed coating film, the strength improvement effect, crack prevention effect, etc., which are equal to or higher than those of the conventional product, can be obtained, and the decrease in elongation seen in the conventional product can be improved.
Although the mechanism of action of the cellulose acetate fiber in the present invention is not clear, it is effective that the fiber has an appropriate hydrophilicity in the chemical composition and that each fiber has a linear and uniform shape. It is inferred.

The fiber length of the cellulose acetate fiber is 0.01 to 10 mm, preferably 0.05 to 5 mm, and more preferably 0.1 to 1 mm.
The fiber diameter of the cellulose acetate fiber is usually 1 to 1000 μm, preferably 10 to 500 μm, more preferably 10 to 100 μm. If the fiber diameter is too small, the dispersibility is poor and foaming may occur. If the fiber diameter is too large, the foaming prevention effect may decrease.

  Cellulose acetate fiber can be produced by a known method. For example, it can be obtained by subjecting cellulose to acetic acid esterification. The degree of esterification of cellulose acetate is not particularly limited, but is usually about 1.5 to 3.

As the cellulose acetate fiber in the present invention, it is particularly desirable to use a waste material of a tobacco filter. Use of such waste material can greatly contribute to resource recycling.
Tobacco filters are used to remove tars in tobacco smoke and maintain taste, and cellulose acetate fibers are widely used as a fiber bundle constituting the filter. When the tobacco filter is manufactured, the remaining cellulose acetate fibers are discharged as waste material.
Such waste cellulose acetate fiber usually has a fiber length of about several cm to several tens of cm. If these are cut to a length of 0.01 to 10 mm using a known cutting machine such as a rotary cutting machine or a push-cutting cutting machine, they can be used for the aqueous coating material of the present invention. If the fiber length of the waste material itself is within a predetermined range, it can be used as it is.

  As the fiber in the aqueous coating material of the present invention, it is desirable to use only the cellulose acetate fiber having the above-mentioned fiber length, but the fiber length is preferably 0.01 to 0.01 as long as the effect of the present invention is not impaired. Mixtures other than 10 mm can also be used. Further, fibers other than cellulose acetate fibers can be used in combination. Examples of such fibers include pulp fibers, acrylic fibers, polyester fibers, nylon fibers, carbon fibers, and the like.

  The mixing ratio of the fibers is 0.01 to 10% by weight, preferably 0.1 to 3% by weight, based on the whole coating material. If the mixing ratio of the fibers is too large, there is a possibility that the workability of coating may be impaired. Further, the extensibility of the formed coating film becomes insufficient. If the mixing ratio of the fibers is too small, it is not possible to obtain a strength improving effect, a crack preventing effect, and the like.

  The aqueous coating material of the present invention can also contain components that can be used for ordinary coating materials. Such components include, for example, thickeners, film-forming aids, leveling agents, wetting agents, plasticizers, antifreezing agents, pH adjusters, preservatives, antifungal agents, antialgal agents, antibacterial agents, dispersants Agents, defoamers, ultraviolet absorbers, antioxidants, catalysts, crosslinking agents, and the like.

  The aqueous coating material of the present invention can be prepared by mixing the above components with a stirrer or the like. In the present invention, since the dispersibility of the cellulose acetate fiber is good, the labor required for the dispersion step can be reduced. In addition, since foaming hardly occurs in the dispersion step, the amount of an antifoaming agent or the like can be reduced.

The aqueous coating material of the present invention can be suitably used as a thick film type aqueous coating material. Specific examples include lysine, stucco, spray tiles, coating materials for forming a concavo-convex pattern such as a single-layer elastic coating material, and base adjustment coating materials such as putties, fillers, and surfacers. The aqueous coating material of the present invention is also suitable as a joint treatment material used for joints between building materials.
The thickness of the formed coating film varies depending on the application, but is generally about 1 to 10 mm. Before painting, water can be mixed if necessary.

  Examples are shown below to further clarify the features of the present invention. In addition, the cellulose acetate fibers 1 and 2 used in each test were obtained from waste materials of tobacco filters. The cellulose acetate fiber 1 had an average fiber diameter of 40 μm and an average fiber length of 0.5 mm. The fiber diameter is 1 μm and the average fiber length is 0.2 mm.

Test I
(1) 2 parts by weight of cellulose acetate fiber 1 was added to 100 parts by weight of a synthetic resin emulsion (acrylate-styrene copolymer resin, pH 7.5, solid content 50% by weight), and the mixture was stirred for 5 minutes with a propeller type stirring blade. did. The specific gravity of the mixture at this time was measured.
Next, 0.2% by weight of a silicone-based defoaming agent was added to the obtained mixture, and the mixture was further defoamed by a rotary defoamer for 5 minutes, and then the specific gravity was measured.
(2) The specific gravity was measured in the same manner as in (1) above, using cellulose acetate fiber 2 instead of cellulose acetate fiber 1.
(3) Pulp fibers (average fiber diameter: 40 μm, average fiber length: 0.5 mm) were used in place of the cellulose acetate fiber 1, and the specific gravity was measured in the same manner as in (1) above.

(Test results)
When observing the appearance before defoaming, the mixture of cellulose acetate fiber 1 and the mixture of cellulose acetate fibers 2 had higher transparency than the pulp fiber mixture. Further, as shown in Table 1, the specific gravity of the mixture of cellulose acetate fiber 1 and the mixture of cellulose acetate fibers 2 before defoaming was higher than that of the pulp fiber mixture.
From the above results, it became clear that foaming of the mixture of cellulose acetate fiber 1 and the mixture of cellulose acetate fiber 2 was less likely to occur than pulp fiber.

Exam II
(1) 45 parts by weight of a synthetic resin emulsion (acrylate-styrene copolymer resin, pH 7.5, solid content of 50% by weight), 5 parts by weight of a titanium oxide dispersion (60% by weight of titanium oxide), and heavy carbonic acid 30 parts by weight of calcium, 15 parts by weight of water, 1 part by weight of a dispersant, 3 parts by weight of a film forming aid, and 1 part by weight of cellulose acetate fiber 1 were added, and the aqueous coating material A was stirred by a propeller-type stirring blade for 30 minutes. Manufactured.
(2) The obtained aqueous coating material A was subjected to an elongation test at 20 ° C. by the method of JIS A6909-2000 7.31 “Elongation test”.

(3) An aqueous coating material B was produced in the same manner as in the above (1) except that the cellulose acetate fiber 2 was used instead of the cellulose acetate fiber 1. The obtained water-based paint B was subjected to an elongation test at 20 ° C. in the same manner as in the above (2).

(4) An aqueous coating material C was produced in the same manner as in (1) above, except that pulp fibers (average fiber diameter: 40 μm, average fiber length: 0.5 mm) were used instead of the cellulose acetate fibers 1. The obtained water-based paint C was subjected to an elongation test at 20 ° C. in the same manner as in the above (2).

(5) An aqueous coating material D was produced in the same manner as in the above (1) except that polypropylene fibers (average fiber diameter: 40 μm, average fiber length: 0.5 mm) were used instead of the cellulose acetate fibers 1. The obtained water-based paint D was subjected to an elongation test at 20 ° C. in the same manner as in the above (2).

(6) An aqueous coating material E was produced in the same manner as in the above (1) except that the following synthetic resin emulsion was used in place of the synthetic resin emulsion of the above (1). The obtained water-based paint E was subjected to an elongation test at 20 ° C. in the same manner as in the above (2).
Cross-linked synthetic resin emulsion: monomer components (styrene, n-butyl acrylate, methyl methacrylate, acrylamide, methacrylic acid, diacetone acrylamide), cross-linking agent (adipate dihydrazide), solid content 50% by weight, glass transition temperature 0 ° C

(Test results)
Table 2 shows the test results. The aqueous coating materials A, B and E containing cellulose acetate fibers are equal to or higher than the aqueous coating materials C (using pulp fibers) and D (using polypropylene fibers) in tensile strength. While showing excellent values in elongation.

Exam III
The following tests were performed on the obtained aqueous coating materials A and E.

(Repeatability test of wet and cold resistance)
A SK water-based elastic sealer (synthetic resin emulsion-based undercoating material; manufactured by SK Chemical Co., Ltd.) is applied to a 150 × 70 × 3 mm flexible plate at 0.15 kg / m ² , and is in a standard state (23 ° C., 50% RH). After drying for 8 hours, water-based coating materials A and E were applied at 4.0 kg / m ² and cured for 14 days to prepare test specimens. According to JIS K5600-1999 7.4, the prepared specimen was immersed in water at 23 ± 2 ° C. for 18 hours, immediately cooled in a thermostat kept at −20 ± 2 ° C. for 3 hours, and then cooled to 50 ± 3 ° C. The mixture was heated for 3 hours in another thermostat kept at ° C. After repeating this operation 10 times, the film was left in a standard state for about 1 hour, and the state of the coating film surface was visually observed. The evaluation is as follows. The test results are shown in Table 3.
○: No crack ×: Crack

(Accelerated contamination test)
A 150 × 75 × 0.8 mm aluminum plate was coated with SK # 1000 primer (epoxy resin base coating material; manufactured by SK Chemical Co., Ltd.) at 0.15 kg / m ² and dried for 8 hours under standard conditions. Thereafter, the aqueous coating materials A and E were applied at 4.0 kg / m ² and cured for 14 days to prepare test specimens.
After the prepared test body was dried and cured in a standard state for 7 days, a 15% by weight aqueous dispersion of carbon black was dropped onto the coating surface so as to have a diameter of 20 mm and a height of 5 mm. For 2 hours. Thereafter, the film was washed in running water, and the degree of contamination on the coating film surface was visually evaluated. The evaluation is as follows. The test results are shown in Table 3.
◎: No trace ○: Almost no trace ×: There is trace

Claims (3)

  An aqueous coating material containing a binder, a granular material, and fibers as essential components and containing 0.01 to 10% by weight of fibers with respect to the entire coating material, wherein the fibers are acetic acid having a fiber length of 0.01 to 10 mm. An aqueous coating material containing cellulose fibers.   The aqueous coating material according to claim 1, wherein the cellulose acetate fiber is a waste material of a tobacco filter. The aqueous coating material according to claim 1, wherein the binder is a cross-linkable binder having a reactive functional group.