JP2747957B2 - Bark and wood board sheet casting composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to relates to a bark-like sheet and wood board sheet, casting molding composition for forming a sheet having a ie bark-like or tree-shaped surface appearance.

[0002]

2. Description of the Related Art Conventionally, for example, to produce artificial wood, for example, a cement mortar is poured into a mold having a bark surface shape similar to that of the artificial wood to be manufactured, hardened, then released, and a paint is applied. The method is commonly used. In this case, an aqueous resin emulsion may be used in combination with the cement mortar, but the resin content was as small as about 5 to 15% by weight based on the cement. This is because when a resin having a diameter of 10 cm is molded, if a large amount of resin is mixed, moisture in the cured product remains without escaping and tends to be insufficiently cured.

[0003] In order to harden a pseudo-wood or the like formed by using the above-mentioned cement / mortar as a main component, it is necessary to reduce the temperature from room temperature to
It must be carried out at a temperature of 60 ° C. in a high humidity atmosphere or in an autoclave, and its curing takes from half a day to 1
It takes a long time of about 0 days.

[0004] In addition, pseudo wood or the like molded using the above-mentioned cement mortar as a main component has a hard base material and a poor tactile sensation because the main component is a cured product of the cement mortar, irrespective of its appearance. Fine projections and the like of cement mortar were formed, and there was a drawback such as injury when touched. In addition, although the material is hard and durable due to its hardness, the material tends to be cracked or chipped due to impact on the other hand. In this case, a base cement layer appears and the appearance is impaired.

[0005] Further, even if the artificial wood is molded using the cement mortar as a main component, its appearance is easily impaired by efflorescence even if its surface is coated (the efflorescence is the surface of hardened cement. Is a precipitate that is dissolved in water and carried and deposited.) In particular, before completely hardening (the full hardening of cement usually takes about 28 days), painting on a material with high surface alkali strength or a material with efflorescence, Easy to peel off paint. Also,
Even during use, new efflorescence is generated from pinholes, scratches, etc., and the appearance may be impaired.

Further, in the cement-mortar type, since the base material is hard, a complicated projection portion or a delicate pattern portion expressing a bark-like appearance is broken at the time of demolding. It is not possible to obtain a molded article that faithfully expresses the bark-like appearance of cedar-like deep and complex irregularities, and conversely, the surface of cherry blossoms, birches, and even baked cedar boards is almost smooth. Also, a molded product faithfully expressing the appearance of bark having a delicate pattern cannot be obtained.

[0007]

DISCLOSURE OF THE INVENTION The present invention has good releasability (releasability) during sheet molding, has a surface appearance very similar to the appearance of bark or wood board, and has an elasticity and a tactile feel. It is an object of the present invention to provide a composition for casting bark-like and wood-like sheets which can be easily formed into bark-like and wood-like sheets which resemble wood and wooden boards and which are rich in bending resistance.

[0008]

The bark-like and wood-like sheet casting composition of the present invention comprises (a) a glass transition point of 5;
100 parts by weight of an aqueous emulsion of a resin at a temperature of not more than 100 ° C (resin solid content), (b) hydraulic inorganic cement powder 140 to 3
It is a composition containing 00 parts by weight, (c) 20 to 120 parts by weight of foam particles, and (d) 0 to 200 parts by weight of a non-hydraulic inorganic powder.

As an aqueous emulsion of (a) a resin having a glass transition point of 5 ° C. or less for preparing a composition for casting and molding bark-like and wood-like sheet of the present invention, for example, acrylic acid 2-
Ethylhexyl [the glass transition point of the homopolymer is -8
5 ° C. (this is abbreviated as “Tg-85 ° C.”)], n-butyl acrylate (Tg-54 ° C.), ethyl acrylate (Tg-22
° C), vinylidene chloride (Tg-18 ° C), isopropyl acrylate (Tg-5 ° C), 2-ethylhexyl methacrylate (Tg-5 ° C), n-propyl acrylate (Tg 8 ° C), n-butyl methacrylate ( Tg 20
° C), vinyl acetate (Tg 30 ° C), acrylic acid (Tg
87 ° C.), n-propyl methacrylate (Tg 81
C), styrene (Tg 100 ° C), acrylonitrile (Tg 100 ° C), methyl methacrylate (Tg 10
5 ° C.), methacrylic acid (Tg 130 ° C.), maleic anhydride, itaconic acid (Tg 130 ° C.), acrylamide (Tg 153 ° C.), ethyl methacrylate (Tg 6
Glass transition point obtained by emulsion polymerization of one or more unsaturated monomers selected from vinyl chloride (Tg 79 ° C), ethylene, butadiene, etc. Emulsion of homopolymer or copolymer at 0 ° C. or lower, and 2
Mixtures of more than one species are used. Further, a resin emulsion (commonly known as a powder emulsion) obtained by redispersing a water redispersible resin powder produced from these emulsions in an aqueous medium can also be used.

The hydraulic mineral cement powder (b) used in the present invention is referred to as portland cement (for example, ordinary cement, white cement, high-strength cement, ultra-high-strength cement, etc.) and mixed cement. (Eg blast furnace cement, silica cement, fish eye cement, etc.), other alumina cement, hydraulic gypsum, etc.
White cement is preferred.

(B) The hydraulic mineral cement powder comprises:
(A) 140 to 300 parts by weight, preferably 160 to 300 parts by weight, based on 100 parts by weight of the resin solid content of the aqueous resin emulsion.
240 parts by weight are used. If the use ratio is too small, the bark-like and wood-plate-like sheets obtained will have reduced elasticity, and will not be able to express complicated irregularities and delicate patterns on the bark surface, etc. Etc. are hard and brittle, especially with water.

Examples of the foam particles (c) in the present invention include inorganic foam particles such as shirasu balloons and foam glass beads, and organic foam particles such as expanded polystyrene. Considering the compatibility and miscibility, inorganic foam particles are preferred. The mixing ratio of the foam particles is
(A) 20 to 120 parts by weight, preferably 40 to 80 parts by weight, based on 100 parts by weight of the resin solid content of the aqueous resin emulsion. If the compounding ratio is too small, the tactile sensation of the bark sheet or the like, particularly the cork texture of the tree, cannot be obtained,
It takes a long time to cure and dry when molding a bark sheet or the like, especially the time required for drying after curing, and the productivity is reduced. If the proportion is too large, the bark sheet or the like becomes hard and brittle.

The non-hydraulic inorganic powder (d) used in the present invention includes, for example, calcium carbonate, silica sand, talc, clay, ceramic particles, various inorganic extender pigments, and inorganic coloring pigments. The non-hydraulic inorganic powder is not an essential component but is preferably blended.
That is, the mixing ratio is from 0 to 200 parts by weight, preferably from 80 to 150 parts by weight, per 100 parts by weight of the resin solid content of the aqueous resin emulsion (a). If the compounding ratio is too large, the resulting bark-like sheet or the like is hard and brittle, and becomes a cured product of cement mortar,
The wood feel is lost and becomes particularly hard when immersed in water.

In order to form a bark-like or wood-like sheet using the composition for casting a bark-like or wood-like sheet of the present invention, the composition is sufficiently added after further adding water as required. After kneading to form a slurry with an appropriate water content, a mold having bark-like or wood-plate-like irregularities or patterns (for example, a negative pattern on the bark-like surface is formed from bark using a silicone resin mold or the like) )), The slurry is poured into the mold, and the mold is pressed from above, molded, and then cured.

On the slurry poured into the mold in that case,
Before curing, put a water-permeable base cloth on it and press and cure it to obtain a bark-like sheet lined with the base cloth,
The strength can be improved, and the adhesiveness at the time of laminating to another thing with an adhesive or the like, or casting a mortar or the like with a sheet as a mold frame and integrally molding is improved.

Examples of the water-permeable base fabric include spunbonds of various synthetic fibers, for example, fibers such as polypropylene, polyethylene, polyethylene terephthalate, and nylon, non-woven fabrics, miscellaneous felts, woven fabrics, and woven fabrics;
Woven cloth such as hemp and wool, glass fiber cloth, and the like.

The thickness of the bark-like and wood-like sheet to be formed is preferably 2 to 30 mm, more preferably 3 to 15 mm.
mm. If it is too thick, it takes a long time for curing and drying, which is not preferable. On the other hand, if it is too thin, the feel of the bark or the like tends to be lost.

The formed bark-like and wooden board-like sheets may be further sprayed with an appropriate powdery colorant on the surface thereof for the purpose of further increasing the bark or wood board-likeness or improving the strength, or by applying a coloring paint or the like. A clear paint or the like can be applied. The powdery colorant can be dispersed in a mold for molding a bark sheet or the like in advance so as to function as a release agent for releasing the molded sheet from the mold.

The bark-like and wooden board-like sheets produced as described above (hereinafter sometimes abbreviated as “bark-like sheets”) can be used in various modes. For example, this bark-like sheet is attached to a tubular or rod-like material such as an iron pipe, concrete pile, plastic rod or pipe, wood log, paper tube, etc., and the seam of the sheet and the upper end of the tube or rod are attached. After filling or applying an aqueous slurry (resin mortar) of the same composition as the composition for forming a bark sheet of the present invention using a brush or iron,
When a pigment powder is sprayed on the surface and solidified, and then a clear resin solution is applied thereon, a pseudo wood is obtained. Alternatively, a bark-like sheet may be provided on the inner surface of the cylinder, and mortar or the like may be poured into the sheet and integrated to form a pseudo tree.

[0020]

EXAMPLES Examples and comparative examples will be described below in more detail. "Parts" described in these examples means parts by weight.

Example 1 900 parts of Acronal S-400 (trade name, manufactured by Mitsubishi Yuka Birdish Co., Ltd., aqueous emulsion of acrylate-styrene copolymer resin, resin solid content: 57%, Tg of resin is 0 ° C. or lower) , 100 parts of white cement, 20 parts of Shirasu balloon (brand name Winilite SB-9011), 15 parts of water, and 1 part of iron oxide red
Parts were mixed and kneaded well to form a slurry.

The slurry is poured into a concave mold having a bark appearance of a sushi made of silicone resin (average wet thickness: 5 mm, maximum wet thickness: 10 mm), and a polyester spunbond base cloth (Mitsui Petrochemical Co., Ltd.) is placed thereon. A trade name (Syntex R-24, basis weight 69 g / m ² ) was placed and pressed to make sufficient contact. Then, it was heated to 140 ° C. from the silicone mold side. After heating for 60 minutes, the mold was removed, and a sheet having an appearance surface of bark-like bark was obtained.

Examples 2 to 7 Comparative Examples 1 to 2 The composition of the sheet composition and the sheet production conditions were changed as shown in Tables 1 and 2, respectively. Was manufactured.

Examples 8 and 9 The composition of the sheet composition and the sheet manufacturing conditions were changed as shown in Table 2, and the bark pattern was changed to the baked cedar board pattern. To produce a sheet.

[0025]

[Table 1]

[0026]

[Table 2]

Notes to Tables 1 and 2: * 1 ... Trade name of Mitsubishi Yuka Birdish Co., Ltd., aqueous emulsion of acrylate-styrene copolymer resin, resin solids concentration 57%, Tg of resin is 0 ℃ or less * 2 ... Ichi Kasei Co., Ltd., Winilite SB
-9011 * 3 ... Mitsui Petrochemical Industries Co., Ltd. trade name, made of polyester spunbond (basis weight 69g / m ²⁾ * 4 ··· Mitsubishi Petrochemical Co., Ltd. Badisshe product name, Acronal YJ-3042D, acrylic acid Aqueous emulsion of ester-styrene copolymer resin, solid content 50%,
The resin has a Tg of 3 ° C * 5: Mitsubishi Yuka Birdish Co., Ltd., Acronal YJ-1560D, an aqueous emulsion of an acrylate-styrene copolymer resin, solid content 48%,
Tg of the resin is 10 ° C * 6: Mitsui Petrochemical Industry Co., Ltd., polypropylene spunbond (basis weight 40 g / m ² )

With respect to each of the sheets obtained in Examples 1 to 9 and Comparative Examples 1 to 3, demolding property, bending property, elasticity, and immersion in water at 20 ° C. or 60 ° C. The appearance of the sheet was examined and evaluated, and the results were as shown in Table 3.

[0029]

[Table 3]

Notes on Table 3: * 1 ... The release properties of the cured / dried sheet were evaluated according to the following criteria.・ ・ ・: Easy release without leaving any residue of the sheet composition in the silicone mold, and no abnormality on the surface of the sheet. Δ: A part of the sheet composition adhered to the mold when the mold was released, and abnormality of the sheet was observed within 10% of the sheet surface. ×: Above 10% of the sheet surface, abnormalities such as tearing and cracking of the sheet are observed.

* 2 ... The bendability was evaluated by placing a cylinder having a diameter of 20 mm on the surface of the bark-like sheet, bending the sheet 180 ° along the cylinder, and visually observing the sheet, and evaluated according to the following criteria. did. ◎: There is no abnormality in the sheet. ・ ・ ・: It takes some time for the bent portion of the sheet to return to the original state. ・ ・ ・: The habit remains in the bent portion of the sheet or whitens. ×: The sheet is broken or cracked.

* 3 ... The elasticity is measured by placing the bark-like sheet on a plywood (thickness: 10 mm) with the back side facing up, 2 kg / c.
The compression deformation after pressing at m ² and then releasing was examined and evaluated according to the following criteria. ◎ ・ ・ ・ There is compression deformation ○ ・ ・ ・ There is some compression deformation △ ・ ・ ・ There is almost no compression deformation × ・ ・ ・ There is no compression deformation

* 4: The appearance was evaluated according to the following criteria. ◎ ・ ・ ・ No abnormality is observed visually × ・ ・ ・ Efflorescence is observed visually

As is clear from Table 3, the sheet of the example is excellent in the releasability, bendability, elasticity, and appearance after immersion in water in a well-balanced manner as compared with the sheet of the comparative example.

[0035]

EFFECT OF THE INVENTION The composition for casting bark-like and wood-plate-like sheets of the present invention is excellent in mold release properties during molding of molded sheets, and the resulting sheets have resistance to bending. It is rich in elasticity and has a surface appearance and a tactile sensation that closely resembles the bark and the wooden board that faithfully expresses the appearance of the bark and the wooden board, and its appearance and tactile sensation do not change much even when exposed to wind and rain.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // B44F 9/02 B44F 9/02 (C04B 28/02 24:26 14:16 14:02) (56) References JP 63-315546 (JP, A) JP-A-4-114943 (JP, A) JP-B-1-48236 (JP, B2)

Claims (1)

(57) [Claims] (A) 100 parts by weight of an aqueous emulsion of a resin having a glass transition point of 5 ° C. or lower (solid content of resin);
A bark comprising (b) 140 to 300 parts by weight of hydraulic mineral cement powder, (c) 20 to 120 parts by weight of foam particles, and (d) 0 to 200 parts by weight of non-hydraulic inorganic powder. And sheet-like sheet casting composition.