JP2010138963A - Synthetic resin pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a synthetic resin pipe of which the pipe inner face has hydrophilicity of 50° or less of contact angle to water, and excellent in productivity and handleability. <P>SOLUTION: This synthetic resin pipe of which at least the pipe inner face has 50° or less of contact angle to the water is constituted to form at least the pipe inner face of a polyvinyl chloride resin composition added with 1-5 pts.wt. of ionic surfactant such as an anionic surfactant and fatty acid ester such as diglycerol stearate, as total thereof, with respect to 100 pts.wt of polyvinyl chloride resin. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a synthetic resin pipe that is hard to adhere to oil such as slime on the inner surface.

Up to now, drainage vertical pipes of condominiums etc. have been regularly washed with high pressure by slime (oil) adhering to the inner surface after long-term use. However, since high costs are incurred in implementing high-pressure cleaning, there is a demand for reducing the burden on the residents by reducing the number of cleanings.
Therefore, in order to make slime less likely to adhere to the inner surface of the tube, the slime adhesion is achieved by making the inner surface of the tube hydrophilic with a water contact angle of 50 degrees or less so that a water film is formed along the inner surface of the tube. Has been proposed (Patent Document 1).

Moreover, as a method of imparting hydrophilicity to the inner surface of the tube, a hydrophilic material is applied to the inner surface of the extruded resin tube, or the resin tube has a multilayer structure and a hydrophilic material is used on the innermost surface. , A method of forming a hydrophilic film or layer on the inner surface of the resin tube, or a method of blending a hydrophilic material in advance with the resin used for molding the resin tube. In the case of a method of preliminarily blending a hydrophilic material with a resin, even if hydrophilicity can be imparted, there are problems that the strength and heat resistance of the tube itself are reduced and that the tube surface is sticky and workability is poor, Substantially, a hydrophilic paint is applied to the inner surface of the tube.
However, the method of applying a hydrophilic paint has a problem that productivity is poor because at least two steps of a tube forming process and a hydrophilic paint applying process are necessary.

Japanese Patent Laid-Open No. 2004-270764

  In view of the above circumstances, an object of the present invention is to provide a synthetic resin tube whose inner surface has hydrophilicity with a contact angle of 50 degrees or less with respect to water, and which is excellent in productivity and handleability.

  In order to achieve the above object, a synthetic resin tube according to the present invention is a synthetic resin tube having a contact angle with water of at least 50 degrees on the inner surface of the tube, and at least the inner surface of the tube is composed of an ionic surfactant and a fatty acid. It is characterized by being formed of a vinyl chloride resin composition obtained by adding 1 to 5 parts by weight of ester to 100 parts by weight of vinyl chloride resin in total.

  In the present invention, the total amount of the ionic surfactant and the fatty acid ester is limited to 2 to 5 parts by weight based on 100 parts by weight of the vinyl chloride resin. If the amount is too small, the contact angle cannot be reduced to 50 degrees or less, and if it exceeds 5 parts by weight, the oil component such as slime does not adhere directly to the inner surface of the pipe, but solids such as dust adhere. This is because slime adheres easily through this garbage.

The ionic surfactant may be any of an anionic surfactant, a cationic surfactant and an amphoteric surfactant, but an anionic surfactant is preferred.
Although it does not specifically limit as an anionic surfactant, For example, a carboxylic acid type, a sulfate ester type, and a sulfonic acid type are mentioned, A sulfonic acid type is preferable.

Although it does not specifically limit as said fatty acid ester, For example, glycerol fatty acid ester, diglycerol fatty acid ester, polyglycerol fatty acid ester is mentioned, Diglycerol fatty acid ester is preferable.
As a fatty acid which comprises fatty acid ester, a C12-C20 thing is preferable.
Specific examples of the diglycerin fatty acid ester include diglycerin laurate, diglyceryl stearate, and diglycerin oleate. Among them, diglycerin stearate is preferable.

  In addition, when the ionic surfactant is an anionic surfactant and the fatty acid ester is a diglycerin fatty acid ester, the mixing ratio is not particularly limited, but the anionic surfactant and the diglycerin fatty acid ester are in weight. It is preferable to be added in a ratio of 20:80 to 60:40. That is, if the proportion of the anionic surfactant is too large, stickiness occurs, and the outer surface of the tube is added with 1 to 5 parts by weight of the ionic surfactant and the fatty acid ester in total with respect to 100 parts by weight of the vinyl chloride resin. When the vinyl chloride resin composition is formed, there may be a problem in handleability. If the blending ratio of the anionic surfactant is too small, the contact angle may not be 50 degrees or less. is there.

  Furthermore, in the vinyl chloride resin composition, if necessary, stabilizers, lubricants, processing aids, impact modifiers, heat resistance improvers, antioxidants, ultraviolet absorbers, light stabilizers, fillers, Various additives such as thermoplastic elastomers, pigments, and plasticizers may be used.

  Examples of the stabilizer include a heat stabilizer and a heat stabilization aid, and the heat stabilizer is not particularly limited. For example, dibutyltin mercapto, dioctyltin mercapto, dimethyltin mercapto, dibutyltin malate, dibutyltin. Organotin stabilizers such as malate polymer, dioctyltin malate, dioctyltin malate polymer, dibutyltin laurate, dibutyltin laurate polymer; lead stearate, dibasic lead phosphite, tribasic lead sulfate, etc. Lead-based stabilizers; calcium-zinc-based stabilizers; barium-zinc-based stabilizers. These may be used independently and 2 or more types may be used together.

The stabilization aid is not particularly limited, for example, epoxidized soybean oil, phosphate ester,
Examples include polyol, hydrotalcite, and zeolite. These may be used alone or in combination of two or more.

  Examples of the lubricant include an internal lubricant and an external lubricant. The internal lubricant is used for the purpose of lowering the flow viscosity of the molten resin during molding and preventing frictional heat generation. The internal lubricant is not particularly limited, and examples thereof include butyl stearate, lauryl alcohol, stearyl alcohol, epoxy soybean oil, glycerin monostearate, stearic acid, and bisamide. These may be used alone or in combination of two or more.

  The external lubricant is used for the purpose of increasing the sliding effect between the molten resin and the metal surface during molding. The external lubricant is not particularly limited, and examples thereof include paraffin wax, polyolefin wax, ester wax, and montanic acid wax. These may be used alone or in combination of two or more.

  The processing aid is not particularly limited, and examples thereof include acrylic processing aids such as alkyl acrylate-alkyl methacrylate copolymers having a weight average molecular weight of 1 to 2 million. The alkyl acrylate-alkyl methacrylate copolymer is not particularly limited, and examples thereof include n-butyl acrylate-methyl methacrylate copolymer and 2-ethylhexyl acrylate-methyl methacrylate-butyl methacrylate copolymer. These may be used alone or in combination of two or more.

The impact modifier is not particularly limited, and examples thereof include methyl methacrylate-butadiene-styrene copolymer (MBS), chlorinated polyethylene, and acrylic rubber.
The heat resistance improver is not particularly limited, and examples thereof include α-methylstyrene-based resins and N-phenylmaleimide-based resins.

It does not specifically limit as said antioxidant, For example, a phenolic antioxidant etc. are mentioned.
The light stabilizer is not particularly limited, and examples thereof include hindered amine light stabilizers.
The ultraviolet absorber is not particularly limited, and examples thereof include salicylic acid ester-based, benzophenone-based, benzotriazole-based, and cyanoacrylate-based ultraviolet absorbers.

The filler is not particularly limited, and examples thereof include calcium carbonate and talc.
The pigment is not particularly limited, and examples thereof include organic pigments such as azo, phthalocyanine, selenium, and dye lake; oxides, molybdenum chromate, sulfide / selenide, ferrocyanide, and the like. An inorganic pigment etc. are mentioned.
The plasticizer is not particularly limited, and examples thereof include dibutyl phthalate, di-2-ethylhexyl phthalate, and di-2-ethylhexyl adipate.

The synthetic resin tube of the present invention is formed of a vinyl chloride resin composition in which only the inner surface is added with 1 to 5 parts by weight of the ionic surfactant and the fatty acid ester with respect to 100 parts by weight of the vinyl chloride resin. The outer surface layer does not need to have hydrophilicity.
Moreover, you may make it provide the intermediate | middle layer comprised with the vinyl chloride resin composition containing a thermal expansion graphite as a fireproof expansion layer between an inner surface layer and an outer surface layer.

  The vinyl chloride resin composition containing thermally expanded graphite preferably contains 1 to 15 parts by weight of thermally expandable graphite with respect to 100 parts by weight of the polyvinyl chloride resin, and the ratio of 1 to 12 parts by weight. More preferably, it is more preferably 2 to 10 parts by weight. That is, if the thermally expandable graphite is less than 1 part by weight of the thermally expandable graphite, sufficient thermal expansion cannot be obtained at the time of combustion, and desired fire resistance cannot be obtained. As a result of the thermal expansion, the shape cannot be maintained and the residue may fall off, resulting in a decrease in fire resistance.

Thermally expandable graphite consists of natural scale-like graphite, pyrolytic graphite, quiche graphite and other powders such as concentrated sulfuric acid, nitric acid, selenic acid and other inorganic acids, concentrated nitric acid, perchloric acid, perchlorate, permanganate, heavy It is a crystalline compound that maintains the layered structure of carbon obtained by acid adjustment by inserting an inorganic acid between graphite layers with a strong oxidizing agent such as chromate or hydrogen peroxide, and then adjusting the pH. It is preferable to use thermally expandable graphite adjusted to pH 1.5 to 4.0 and thermally expandable graphite having a 1.3 times expansion temperature of 180 ° C to 240 ° C.
That is, if the pH of the heat-expandable graphite is less than 1.5, the acidity is too strong to easily cause corrosion of the molding apparatus. If the pH exceeds 4.0, the effect of promoting the carbonization of the polyvinyl chloride resin It may become thin and sufficient fire resistance performance may not be obtained.

The synthetic resin pipe according to the present invention is a synthetic resin pipe having a contact angle with water of at least 50 degrees on the inner surface of the pipe, and at least the inner surface of the pipe is a total of a vinyl chloride resin containing an ionic surfactant and a fatty acid ester. Since it is formed of a vinyl chloride resin composition added by 1 to 5 parts by weight with respect to 100 parts by weight, the inner surface of the pipe has hydrophilicity with a contact angle of 50 degrees or less with respect to water, and slime adhesion can be reduced. Therefore, when used as a drainage vertical pipe, the frequency of high-pressure cleaning of the drainage vertical pipe can be reduced. And since it can manufacture only by extrusion molding, it is excellent in productivity.
Further, the ionic surfactant is an anionic surfactant, the fatty acid ester is a diglycerin fatty acid ester, and the anionic surfactant and the diglycerin fatty acid ester are in a weight ratio of 20:80 to 60:40. If the vinyl chloride resin composition added in a proportion is used, the strength and heat resistance are not lowered, and the handleability is excellent.
Furthermore, if it consists of three layers of an inner surface layer, an intermediate | middle layer, and an outer surface layer and the intermediate | middle layer is formed with the vinyl chloride resin composition containing thermally expanded graphite, it can be used also as a refractory tube.

Examples of the present invention will be described in detail below.
(Example 1)
For 100 parts by weight of vinyl chloride resin (TS1000R manufactured by Tokuyama Sekisui Kogyo Co., Ltd.), 1 part by weight of anionic surfactant sodium alkane sulfonate (Riken Vitamin Riquemar SE-11), diglycerin stearate (RIKEN Vitamin) A vinyl chloride resin composition containing 1 weight of Riquemar S-71-D) was extruded to obtain a sample plate having a thickness of 8 mm.

(Example 2)
A sample plate was obtained in the same manner as in Example 1 except that the blending amounts of the anionic surfactant and diglyceryl stearate were 1.5 parts by weight, respectively.

Example 3
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant and diglycerin stearate was 2.5 parts by weight.

Example 4
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 0.8 part by weight and the amount of the diglyceryl stearate was 1.2 parts by weight.

(Example 5)
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 1.2 parts by weight and the amount of the diglyceryl stearate was 1.8 parts by weight.

Example 6
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 2 parts by weight and the amount of diglyceryl stearate was 3 parts by weight.

(Example 7)
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 0.6 parts by weight and the amount of diglyceryl stearate was 2.4 parts by weight.

(Example 8)
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 1 part by weight and the amount of diglyceryl stearate was 4 parts by weight.

(Comparative Example 1)
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 0.2 parts by weight and the amount of the diglyceryl stearate was 0.8 parts by weight.

(Comparative Example 2)
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 0.3 part by weight and the amount of diglycerin stearate was 2.7 parts by weight.

(Comparative Example 3)
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 0.1 part by weight and the amount of diglyceryl stearate was 0.9 part by weight.

(Comparative Example 4)
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 0 part by weight and the amount of the diglyceryl stearate was 3 parts by weight.

(Comparative Example 5)
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 0 part by weight and the amount of the diglyceryl stearate was 5 parts by weight.

(Comparative Example 6)
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 2 parts by weight and the amount of diglyceryl stearate was 0 parts by weight.

(Comparative Example 7)
A sample plate was obtained in the same manner as in Example 1 except that the amount of the anionic surfactant was 5 parts by weight and the amount of diglyceryl stearate was 0 parts by weight.

(Comparative Example 8)
A vinyl chloride resin composition containing 5 parts by weight of glycerin monostearate (Riken Vitamin Co., Ltd. Rikemar S-100A) is extruded to 100 parts by weight of vinyl chloride resin (TS1000R manufactured by Tokuyama Sekisui Kogyo Co., Ltd.), and the thickness is 8 mm. A sample plate was obtained.

(Comparative Example 9)
A vinyl chloride resin composition in which 5 parts by weight of sorbitan stearate (Riken Vitamin Co., Ltd. Riquemar S-300W) is blended with 100 parts by weight of vinyl chloride resin (Tokuyama Sekisui Kogyo TS1000R) is 8 mm thick. A sample plate was obtained.

(Comparative Example 10)
A sample plate having a thickness of 8 mm was obtained using only a vinyl chloride resin (TS1000R manufactured by Tokuyama Sekisui Kogyo Co., Ltd.).

Each of the sample plates obtained in Examples 1 to 9 and Comparative Examples 1 to 10 was examined for contact angle with water and the presence or absence of stickiness, and the results are shown in Tables 1 and 2.
The contact angle was measured according to the method of JIS K2396. Stickiness was evaluated qualitatively by touching the surface of the sample plate with fingers.

Claims (3)

  A synthetic resin pipe having a water contact angle of at least 50 degrees with respect to water on the inner surface of the pipe, and at least the inner surface of the pipe is 2 to 5 with respect to 100 parts by weight of vinyl chloride resin in total of ionic surfactant and fatty acid ester. A synthetic resin pipe formed of a vinyl chloride resin composition added with parts by weight.   The ionic surfactant is an anionic surfactant, the fatty acid ester is a diglycerin fatty acid ester, and the anionic surfactant and the diglycerin fatty acid ester are in a weight ratio of 20:80 to 60:40. The synthetic resin pipe according to claim 1, which is added.   The synthetic resin pipe according to claim 1 or 2, comprising an inner layer, an intermediate layer and an outer surface layer, wherein the intermediate layer is formed of a vinyl chloride resin composition containing thermally expanded graphite.