JPH1087904A - Colored resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition containing a polyolefin resin, a pigment, and a metal oxide, excellent in chlorine-containing water resistance and capable of providing such a molded product as not generating bubbles on its surfaces, even when directly brought into contact with the chlorine- containing water. SOLUTION: This colored resin composition comprises (A) a polyolefin resin (preferably polyethylene, polypropylene or polybutene), (B) a pigment (preferably a blue pigment), and (C) a divalent metal oxide (preferably ZnO, MgO, CaO). Pellets to be supplied to molding processes as such among the composition preferably comprise 100 pts.wt. of the component A, 0.01-10 pts.wt. of the component B and 0.001-10 pts.wt. of the component C. A pellet-like coloring agent (master batch) containing the pigment in a high concentration preferably comprises 100 pts.wt. of the component A, 0.1-100 pts.wt. of the component B and 0.02-100 pts.wt. of the component C. Molded products suitable for use in the pipes of water supply, etc., can thereby be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a colored resin composition for a colored resin molded article which comes into direct contact with chlorine-containing water.
More specifically, the present invention relates to a colored resin composition that can provide a molded article that does not generate water bubbles on the surface of the molded article even when the molded article is in direct contact with chlorine-containing water.

[0002]

2. Description of the Related Art In order to color-mold a polyolefin resin such as polyethylene or polypropylene, inorganic pigments such as zinc oxide, titanium oxide, red iron oxide, ultramarine, cobalt blue, etc.
Organic pigments such as azo type, quinacridone type, anthraquinone type, perylene type, isoindolinone type, phthalocyanine type, dioxazine type, indasulen type, perinone type, quinophthalone type, etc., azo type, anthraquinone type, perylene type, perinone type And thioindigo dyes. When a molded product obtained by blending the above-described dye and pigment with a polyolefin resin is used in direct contact with chlorine-containing water, for example, when used for a water supply pipe or the like, water bubbles are generated on the surface of the molded product, and such water bubbles are generated. There has been a problem that the molded product is peeled and a part of the peeled molded product is mixed into the water.

In particular, in the case of water supply pipes, due to the property that tap water is used for eating and drinking, severe performance as defined in JIS K6762 is required for generation of water bubbles and peeling of water bubbles (partial mixing of molded products). It has been demanded. Therefore, a two-layer tube has been proposed in which a layer containing no pigment is provided on the inner surface that directly contacts the chlorine-containing water, and a layer containing the pigment is provided on the outer surface. However, such a two-layer tube has problems that it is more difficult to manufacture than a single-layer tube and requires a special molding machine. Also, the joint connecting the pipes
Since it is difficult to form a two-layer structure from the viewpoint of structure, a colored resin composition having excellent chlorine-containing water resistance even in a single layer is desired.

[0004]

An object of the present invention is to improve the above-mentioned drawbacks and to provide a colored resin composition having excellent chlorine-containing water resistance.

[0005]

A first aspect of the present invention is a chlorine-resistant water colored resin composition containing a polyolefin resin, a pigment and a divalent metal oxide.

The second invention is a polyolefin resin 100
It is a chlorine-resistant water-containing colored resin composition, which contains 0.1 parts by weight of a pigment, 0.01 to 10 parts by weight of a pigment, and 0.001 to 10 parts by weight of a divalent metal oxide.

A third invention is a polyolefin resin 100
A chlorine-resistant water-containing colored resin composition, comprising 0.1 to 100 parts by weight of a pigment, 0.1 to 100 parts by weight of a pigment, and 0.02 to 100 parts by weight of a divalent metal oxide.

In a fourth aspect, the divalent metal oxide is Zn
The colored resin composition for chlorine-containing water according to any one of the first to third inventions, which is at least one selected from the group consisting of O, MgO, and CaO.

A fifth invention is the chlorine-containing water-containing colored resin composition according to any one of the first to fourth inventions, which comprises a dye.

A sixth invention is the chlorine-resistant water-containing colored resin composition according to any one of the first to fifth inventions, wherein the pigment is a blue pigment.

A seventh invention is the chlorine-resistant water-containing colored resin composition according to any one of the first to sixth inventions, which is used for a water pipe.

An eighth invention is the chlorine-resistant water-containing colored resin composition according to any one of the first to seventh inventions, which is used for a water supply pipe.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The polyolefin resin used in the present invention includes, for example, polyethylene, polypropylene, polybutene and the like, and polyethylene and polybutene are preferred. Examples of polyethylene include various types such as high density (H), low density (L), and linear low density (LL). Among water pipes, high density (H) is used for large-diameter water pipes. Linear low density (LL) for small diameter
Is preferred.

The pigment used in the present invention includes:
Inorganic pigments such as zinc oxide, titanium oxide, red iron oxide, ultramarine, cobalt blue, etc., azo-based, quinacridone-based, anthraquinone-based, perylene-based, isoindolinone-based, phthalocyanine-based, dioxazine-based, indazlen-based, perinone-based, quinophthalone Organic pigments and the like may be mentioned. In the case of water pipes, it is preferable to distinguish them from gas pipes and other pipes that are colored green, and to color them blue to image water, so that ultramarine, cobalt blue, It is preferable to use a phthalocyanine-based or indaslen-based blue pigment. Further, a dye may be used for the purpose of improving sharpness, but a water-insoluble dye must be selected.

The divalent metal oxide used in the present invention is preferably ZnO, MgO, or CaO. Although the mechanism of water bubble generation and its suppression is not clearly elucidated, the formation of water bubbles and water bubbles in areas that come into contact with chlorine-containing water due to the penetration of chlorine dissolved in water into molded products. It is believed that delamination occurs. 2
It is considered that by containing the valent metal oxide, the divalent metal oxide can suppress the above-mentioned generation of water bubbles and peeling of water bubbles due to a chlorine trapping action and a neutralizing action.

The chlorine-resistant water-containing colored resin composition of the present invention may be in the form of pellets (colored pellets) to be directly used for molding, or may be a so-called masterbatch containing a pigment at a high concentration. A colorant in the form of a pellet may be used. When the pigment is contained at a high concentration, the colorant may be diluted with a polyolefin resin and subjected to molding to obtain a molded product.

Among the chlorine-resistant colored resin compositions for water containing water of the present invention, in the case of pellets to be directly used for molding, 100 parts by weight of polyolefin resin, 0.01 to 10 parts by weight of pigment, and divalent metal oxide Preferably contains 0.001 to 10 parts by weight of chlorine. If the amount of the pigment is less than 0.01 part by weight, only a very light colored state can be obtained. Further, when the pigment is contained in an amount of more than 10 parts by weight, mechanical properties and the like as a molded article are easily damaged. When the amount of the divalent metal oxide is less than 0.001 part by weight, the effect of suppressing the generation of water bubbles is extremely small,
On the other hand, if the divalent metal oxide is contained in an amount of about 10 parts by weight, the effect of suppressing the occurrence of water bubbles is not only sufficient, but if the divalent metal oxide is contained too much, the mechanical properties and the like as a molded article are easily impaired. . The amount of the divalent metal oxide is preferably 0.1 to 10 times the weight of the pigment.

Among the chlorine-resistant water-based colored resin compositions of the present invention, in the case of a pellet-shaped colorant (masterbatch) containing a pigment at a high concentration, 100 parts by weight of a polyolefin resin and 0.1 to 100 pigments are used. It is preferable to contain 0.02 to 100 parts by weight of a divalent metal oxide. If the amount of the pigment is less than 0.1 part by weight, it is difficult to obtain a desired colored state in the molded article. If the amount of the pigment exceeds 100 parts by weight, granulation of the master batch becomes difficult. If the amount of the divalent metal oxide is less than 0.02 parts by weight, the effect of chlorine water resistance tends to be insufficient, while if it exceeds 100 parts by weight, granulation of the master batch becomes difficult. The amount of the divalent metal oxide is preferably 0.1 to 10 times the weight of the pigment.

When the pigment is contained at a high concentration as described above, a pellet-shaped chlorine-containing water-containing colored resin composition for water is used as a coloring agent, and the coloring agent is diluted with a polyolefin resin and subjected to molding. What is necessary is just to obtain a molded product. Examples of the polyolefin resin used for dilution include those similar to the polyolefin resin used for obtaining a chlorine-containing water-containing colored resin composition in the form of pellets containing a pigment at a high concentration. The final molded product is 100 parts by weight of the polyolefin resin and the pigment is 0.01 to 100 parts by weight, as in the case of the pellet which is directly used for the molding without the need for the dilution.
It is preferable to contain 10 parts by weight and 0.001 to 10 parts by weight of a divalent metal oxide.

Comparing the masterbatch with the colored pellets, there is no significant difference in the processing steps and the like. The masterbatch is slightly more expensive than the colored pellets because the pigment contains a high concentration of pigment. Since the molded product is obtained by diluting with a polyolefin resin 0.5 to 200 times, when compared with the final molded product, the molded product is diluted with the polyolefin resin using the masterbatch, compared with the case where the molded product is obtained with colored pellets. Is preferred because it is inexpensive.

The chlorine-resistant colored water-containing resin composition of the present invention can be formed into various forms such as films, sheets, plates, various containers, pipes, fibers, etc., and is said to be excellent in chlorine-water resistance. From the viewpoint of functions, it is preferable that the pipe is formed into a pipe for water supply, in particular, a pipe for water supply. In the present invention, the pipe also refers to a pipe as a pipe body and a part (joint) used for joining the pipe.

As long as the effects of the present invention are not impaired, metal soaps, dispersants such as medium- and low-molecular-weight polyethylenes, antioxidants, ultraviolet absorbers and the like can be appropriately blended.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail based on embodiments. [Example 1] Polyethylene resin (density 0.95 (JI
S K 6760), MFR 0.062 g / 10 min
(190 ° C., 2.16 kgf)) 100 parts by weight were mixed with 0.7 parts by weight of low molecular weight polyethylene, 0.7 parts by weight of phthalocyanine blue, and 1 part by weight of calcium oxide, and the mixture was kneaded with a uniaxial kneader. Granulated. Thereafter, the plate was molded by an injection molding machine, and a chlorine-containing water resistance test was performed under the following conditions in accordance with JIS K6762, and the state of water bubble generation was examined.・ Test conditions Chlorine concentration: 2000 ± 100 ppm Temperature: 60 ° C. Immersion time: 168 hours ・ Evaluation criteria 1: 10 bubbles of 0.4 mm or more in diameter in 1 cm ²
There are more than one. 2 ... 4 cm or more of water bubbles with a diameter of 0.4 mm or more in 1 cm ²
There are nine. 3. Less than 4 water bubbles having a diameter of 0.4 mm or more exist in 1 cm ² .

Example 2 A plate was obtained in the same manner as in Example 1 except that magnesium oxide was used instead of calcium oxide, and the state of occurrence of water bubbles was examined.

Example 3 A plate was obtained in the same manner as in Example 1 except that zinc oxide was used instead of calcium oxide, and the state of occurrence of water bubbles was examined.

Example 4 Polyethylene resin (density 0.95 (JIS K 6760), MFR 0.062)
g / 10 min (190 ° C., 2.16 kgf)), 80 parts by weight, 10 parts by weight of low molecular weight polyethylene, 10 parts by weight of phthalocyanine blue, and 10 parts by weight of calcium oxide, and the mixture is kneaded and granulated by a uniaxial kneader. Then, a master batch was obtained. 5 parts by weight of the master batch and 100 parts by weight of the same polyethylene resin as the above-mentioned polyethylene resin were mixed, and a plate was molded by an injection molding machine. The state of water bubble generation was examined in the same manner as in Example 1.

Example 5 A plate was obtained in the same manner as in Example 4 except that magnesium oxide was used instead of calcium oxide, and the state of occurrence of water bubbles was examined.

Example 6 A plate was obtained in the same manner as in Example 4 except that zinc oxide was used instead of calcium oxide, and the state of occurrence of water bubbles was examined.

Comparative Example 1 Polyethylene resin (density 0.95 (JIS K 6760), MFR 0.062
g / 10min (190 ° C, 2.16kgf)) 100
0.7 parts by weight of low molecular weight polyethylene and 0.7 parts by weight of phthalocyanine blue were blended with the parts by weight, and the mixture was kneaded and granulated by a single screw kneader. Thereafter, the plate was molded using an injection molding machine, and a chlorine-containing water resistance test was performed under the following conditions in accordance with JIS K6762 to confirm the state of water bubble generation.

[0030]

[Table 1]

[0031]

As described above, according to the present invention, a colored resin composition having excellent chlorine-containing water resistance can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16L 9/12 F16L 9/12 // C08J 5/00 CES C08J 5/00 CES

Claims (8)

[Claims] 1. A chlorine-resistant water-containing colored resin composition comprising a polyolefin resin, a pigment and a divalent metal oxide. 2. 100 parts by weight of polyolefin resin, 0.01 to 10 parts by weight of pigment, 0.001 to 0.01 parts of divalent metal oxide
A chlorine-resistant water-containing colored resin composition comprising 10 parts by weight. 3. 100 parts by weight of polyolefin resin, 0.1 to 100 parts by weight of pigment, 0.02 to 1 of divalent metal oxide
A chlorine-resistant water-containing colored resin composition, comprising 00 parts by weight. 4. The divalent metal oxide is ZnO, MgO,
The chlorine-containing colored resin composition for water according to any one of claims 1 to 3, which is at least one selected from the group consisting of CaO. 5. The colored resin composition for chlorine-containing water according to claim 1, further comprising a dye. 6. The colored resin composition for chlorine-containing water according to claim 1, wherein the pigment is a blue pigment. 7. The chlorine-resistant water-containing colored resin composition according to claim 1, which is used for a water pipe. 8. The colored resin composition for chlorine-containing water according to claim 1, which is used for a water supply pipe.