JP2005325152A - Baseboard - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a baseboard made from an incineration-problem-free non-vinyl-chloride resin, possessing such good applicability as to not undergoing whitening and cracking when bent at a recessed or projected corner and undergoing little dimensional change with a temperature change. <P>SOLUTION: The baseboard comprises a layer of a thermoplastic resin prepared by dispersing 5 to 50 pts.wt. ethylene/propylene copolymer rubber microparticles having a mean particle diameter of 0.1 to 0.5 μm in 50 to 95 pts.wt. homopolypropylene resin. In one embodiment, 5 to 20 pts.wt., per 100 pts.wt. above thermoplastic resin, woody filler having a mean particle diameter of 1-200 μm is further contained. This baseboard can exhibit a low coefficient of linear thermal expansion as well as an initial bending modulus kept at a value as small as 80 to 500 MPa and can be therefore applied to recessed or projected corners in a room without undergoing whitening or cracking caused by bending and without causing a joint gap or abutment raise to form between it and the adjacent skirting board. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a baseboard for attaching the interior wall of a building in contact with the floor, in particular, using an environmentally friendly non-vinyl chloride resin, and even if bent at the entrance corner or the exit corner It relates to a baseboard that has a workability that does not crack or whiten and is also resistant to scratches.

  Many conventional baseboards use a flexible polyvinyl chloride (polyvinyl chloride) resin in consideration of the bendability at the entrance and exit corners. However, PVC resins have been problematic because they can generate hydrogen chloride gas or dioxins when burned.

  Then, instead of the vinyl chloride resin, as shown in the following Patent Document 1, a baseboard using a polyolefin resin not containing chlorine has been proposed. However, since the baseboard made of polyolefin resin is too hard, if it is folded at the entrance and exit corners of the room, the resin will be stretched by bending, so it will whiten due to neck-in and follow the elongation. There was a problem that it was not cracked and was inferior in cutting or cutting workability.

  In order to satisfy these performances, it may be possible to soften by adding low density polyethylene as a softening agent to homopolypropylene resin, or using random homopolypropylene resin instead of homopolypropylene resin. .

However, when the flexibility is increased as described above, the rigidity and surface hardness are insufficient, the scratch resistance is reduced, the linear expansion coefficient is increased, the dimensional stability against temperature change is lowered, and the temperature is low. There are problems, such as generating gaps between the baseboards in the case of, and floating due to the thrusting of the baseboards at high temperatures.
JP 2000-336919 A

  The present invention has been made to solve such problems, and the problem is to use a non-vinyl chloride resin that does not cause a problem during combustion and bend it at the corners of entry and at the corners of exit. However, the present invention is to provide a baseboard having good workability that does not cause whitening or cracking and having a small dimensional change due to temperature change.

  The present invention solves this problem, that is, the invention according to claim 1 is characterized in that ethylene-propylene copolymer rubber fine particles having an average particle diameter of 0.1 to 0.5 μm are contained in 50 to 95 parts by weight of a homopolypropylene resin. A baseboard having a thermoplastic resin layer dispersed in an amount of 5 to 50 parts by weight.

  The invention according to claim 2 is characterized in that 5 to 20 parts by weight of a woody filler having an average particle diameter of 1 to 200 μm is contained in 100 parts by weight of the thermoplastic resin. A skirting board.

  According to the first aspect of the present invention, since no vinyl chloride resin is used, there is no possibility that hydrochloric acid gas or dioxin is emitted even if burned. In addition, when 50 to 95 parts by weight of homopolypropylene resin is dispersed with 5 to 50 parts by weight of ethylene-propylene copolymer rubber fine particles having an average particle size of 0.1 to 0.5 μm, the initial flexural modulus is reduced. It becomes possible to suppress the value to a low value of 80 to 500 Mpa and to make the coefficient of linear expansion low, which makes it difficult to cause whitening or cracking even when folded at the entrance and exit corners of the room. No gaps or thrusts occur.

  According to the invention of claim 2, in addition to the appearance effect of giving a warm wood texture from the inorganic texture that is felt only with plastic by adding a wood filler, the surface hardness is In addition to being further raised and less likely to be scratched, it can be easily cut with a saw or cutter, so it does not generate burrs or whiskers, eliminates the need for deburring during on-site processing, and improves workability. There are benefits.

  The best form of the baseboard in this invention has a layer which consists of a molded object of the mixed composition of a thermoplastic resin and a wood type filler.

  The thermoplastic resin may be obtained by dispersing 5 to 50% by weight of ethylene-propylene copolymer rubber fine particles having an average particle size of 0.1 to 0.5 μm in 50 to 95% by weight of a homopolypropylene resin. This is a feature of the present invention.

  By dispersing the ethylene-propylene copolymer rubber fine particles in the homopolypropylene resin, the bending initial elastic modulus is generally lowered and the flexibility is increased, compared with a homopolypropylene resin generally having an initial bending elastic modulus exceeding 500 MPa, While the machinability and flexibility are greatly improved, the thermal expansion and contraction of the homopolypropylene resin is absorbed by the ethylene-propylene copolymer rubber fine particles by its elastic action, so that the linear expansion coefficient does not increase but decreases. Thus, the dimensional stability against temperature change is improved. Moreover, due to the excellent elastic action of the ethylene-propylene copolymer rubber fine particles, permanent deformation due to the action of pressure hardly occurs despite its high flexibility, compared with the case of using a homopolypropylene resin alone. Even so, the scratch resistance is not reduced.

  In this manner, various performances as a baseboard such as scratch resistance, dimensional stability against temperature change, and construction suitability such as cutting or cutting suitability and appropriate flexibility can be achieved.

  The reason why the average particle diameter and blending amount of the ethylene-propylene copolymer rubber fine particles are defined as described above is that when the blending amount is less than 5% by weight, the effect of addition is poor, and conversely, when the blending amount exceeds 50% by weight. When the average particle size exceeds 0.5 μm, the resin becomes flexible but the linear expansion coefficient is reduced. This is because if the effect is lost and the average particle size is less than 0.1 μm, the dispersion in the homopolypropylene resin described later becomes extremely difficult and the utility is lost.

  As the homopolypropylene resin in the present invention, in addition to the homopolypropylene resin which is a homopolymer of propylene, an unsaturated carboxylic acid such as maleic acid or its anhydride is graft-polymerized in order to improve the adhesiveness with a wooden filler. A modified homopolypropylene resin such as an acid-modified homopolypropylene resin may be appropriately blended.

  Further, by adding a wood-based filler, a warm texture with a wood texture can be obtained, the surface hardness can be further increased, the linear expansion coefficient can be reduced, and the machinability can be improved.

  The addition amount of the wood filler is suitably 5 to 20 parts by weight with respect to 100 parts by weight of the homopolypropylene resin. This is because if it is 20 parts by weight or more, cracking and whitening will occur when it is bent at the protruding corner and the entering corner. Moreover, it is because the texture of wood does not come out if it is 5 weight part or less.

  The material of the wood-based filler used can be selected without any particular restrictions, but in general, the wood is broken by a cutter mill or the like, and this is crushed by a ball mill or an impeller mill, Use fine powder (wood flour).

  It is important that the average particle diameter of the wood filler is 1 to 200 μm, preferably 10 to 150 μm. Those having an average particle size of less than 1 μm are difficult to handle, and particularly when the amount of the wood filler is large, the dispersion into the resin is poor. If it is larger than 200 μm, the uniformity and flatness of the molded product will be deteriorated, and the compatibility with polypropylene will be deteriorated. Therefore, when it is bent at the time of construction, cracks may occur at that portion.

  Moreover, in order to improve the adhesiveness between the wood filler and the homopolypropylene resin, the following can be mixed. For example, by increasing the compounding ratio of an acid-modified resin, such as polyethylene or polypropylene obtained by graft copolymerization with an unsaturated carboxylic acid such as maleic acid or its anhydride, and making the resin itself polar, It is desirable to increase adhesion.

  In the baseboard according to the present invention, a heat stabilizer, an acid neutralizer, an ultraviolet absorber, a light stabilizer, a colorant such as a pigment and a dye, a filler, an antistatic agent, a lubricant, and a nucleating agent are used as necessary. A flame retardant, an antiblocking agent, a dehydrating agent, a light scattering agent for making translucent, a gloss adjusting agent, and the like can also be added.

  Among these additives, hindered phenols, sulfurs, phosphoruss, etc. as heat stabilizers, stearic acid metal salts, hydrotalcite, etc. as acid neutralizers, benzotriazoles, benzoates as ultraviolet absorbers, etc. Benzophenone, triazine, etc., and light stabilizers include hindered amines.

  Examples of flame retardants include halogen flame retardants, phosphorus flame retardants, and chlorine flame retardants. Fillers include calcium carbonate, silica, titanium oxide, barium sulfate, zinc oxide, alumina, talc, mica, magnesium silicate, and titanium. Examples include potassium acid, magnesium sulfate, aluminum hydroxide, magnesium hydroxide, iron oxide, carbon black, and metal powder.

  As lubricants, hydrocarbon lubricants, fatty acids, higher alcohols, fatty acid amides, metal soaps, esters, fluorines, etc. As nucleating agents, carboxylate metal salts, sorbitol, phosphate ester metal salts, etc. Examples of pigments include condensed azo, insoluble azo, quinacridone, isoindolinone, anthraquinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, mica, and other pearl pigments. Generally, it is used in combination.

  In the present invention, the homopolypropylene resin, the ethylene-propylene copolymer rubber fine particles, the wood filler, and other additives are not particularly limited, but are kneaded by a Banbury mixer and pelletized by a pelletizer. The method and the method of mixing and pelletizing by a twin screw extrusion kneader are common. In addition, if the moisture content of the wood-based filler is large, it causes foaming during pelletization. Therefore, it is desirable to suppress the moisture content to 8% or less in advance using a dryer or hopper dryer before kneading.

  50 parts by weight of a commercially available polypropylene resin (bending initial elastic modulus 1500 MPa), 100 parts by weight of a wood-based filler having an average particle size of 100 μm, which is obtained by breaking a wood powder with a cutter mill and pulverizing it with a ball mill. 3 parts by weight of calcium stearate-based lubricant was mixed with a twin-screw extrusion kneader and pelletized to prepare a woody resin composition.

50% by weight of ethylene-propylene copolymer rubber fine particles having a particle diameter of 0.2 to 0.3 μm is obtained with respect to 18% by weight of this wood resin composition (6% by weight of homopolypropylene and 12% by weight of wood filler). 100 parts by weight of dispersed homopolypropylene resin (Cataloy KS081P manufactured by Sun Allomer Co., Ltd.) was added and formed into a long shape having a width of 6.2 cm and a thickness of 1.5 mm by a single screw extruder, and a baseboard having a bending initial elastic modulus of 400 MPa. Was made.
<Comparative Example 1>
A baseboard having the same shape was prepared with 40 parts by weight of the wood-based filler (wood powder) contained in the baseboard.
<Comparative example 2>
Using a resin composition in which 40 parts by weight of a polyethylene resin was added to 100 parts by weight of a polypropylene resin, a baseboard having the same shape was produced.
<Comparative Example 3>
The baseboard of the same shape was produced using only polypropylene resin.

The following evaluation was performed with respect to the above Examples and Comparative Examples.
<90 degree bending process>
For the projecting corner, the produced sample is cut into a width of 6 cm and a flow direction of 5 cm, and the receiving jig as shown in FIG. 1 has a 90-degree recessed V-shape and the pushing jig has a 90-degree protruding V-shape. The receiving jig was pressed with the surface facing down outside of the V shape and pressed. For entering the corner, the sample was cut as described above, and set in a press machine receiving jig so that the surface was inside the V shape and pressed. As a result, the case of cracking was rated as x, the case of no cracking but whitening was marked as Δ, and the case of neither cracking nor whitening was marked as ○.
<Pencil hardness test>
It was carried out according to JIS. Moreover, the linear expansion coefficient was measured.

以上に示したように、実施例１は９０度折れ曲げ試験で割れも白化もしないにも関わらず、表面硬度も低下していないものなり、線膨張係数もポリプロピレン樹脂のみの比較例３よりも低下したものとなった。

As described above, Example 1 is a 90-degree bending test in which neither crack nor whitening occurs, but the surface hardness is not reduced, and the linear expansion coefficient is also higher than that of Comparative Example 3 using only the polypropylene resin. It was a decline.

It is explanatory drawing of the press machine of a 90 degree bending process.

Explanation of symbols

1 ... Sample 2 ... Pushing jig 3 ... Receiving jig

Claims (2)

  It has a thermoplastic resin layer in which 5 to 50 parts by weight of ethylene-propylene copolymer rubber fine particles having an average particle size of 0.1 to 0.5 μm are dispersed in 50 to 95 parts by weight of a homopolypropylene resin. A skirting board.   The baseboard according to claim 1, wherein 100 parts by weight of the thermoplastic resin contains 5 to 20 parts by weight of a wood filler having an average particle diameter of 1 to 200 µm.

Images