JP2001170927A - Method for manufacturing polyolefin colored resin molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for easily manufacturing a molding which is formed of a polyolefin colored resin of desired tint using a simple installation setup. SOLUTION: A polyolefin raw material and pigment are loaded into a rapid dispersing biaxial kneader 11, in which, the raw material and the pigment are, in turn, thermally kneaded at a specified temperature. Then the mixture is introduced into a die 13 to obtain a polyethylene colored pipe P, a molding of a specified shape made in the polyolefin colored resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyolefin-colored resin molded article, and more particularly, to a resin molded article colored by adding a pigment to a polyolefin, and in particular,
The present invention relates to a method for manufacturing a colored pipe.

[0002]

2. Description of the Related Art Polyolefin pipes, for example, polyethylene pipes, are generally manufactured by extruding a resin with a single screw extruder and passing the resin through a die having a predetermined shape. ing. When producing a colored pipe using such a single-screw extruder, even if a mixture obtained by mixing the raw resin and the pigment at a predetermined ratio into the single-screw extruder, the raw resin in the extruder and The kneading with the pigment is not sufficiently performed, and the dispersion of the pigment in the resin becomes insufficient and non-uniform, so that defects such as uneven color and insufficient strength are generated in the molded pipe.

[0003] Therefore, when producing a colored pipe, a polyethylene raw material, which is a raw material resin, and colored pellets produced in a separate process in advance are charged into a mixer at a predetermined ratio, and the mixture is sufficiently mixed by the mixer. I am trying to put it in.

[0004] However, the colored pellets are obtained by extruding a resin / pigment mixture containing a large proportion of the pigment into an appropriate shape and then pulverizing the molded product with a pelletizer. In addition to the extrusion molding step, it was necessary to perform a molding step for obtaining colored pellets and a pulverizing step. In addition, in terms of equipment, a mixer, an extruder, a die, a crusher, and the like are necessary only for producing colored pellets. Equipment is required, and in addition to these, cooling equipment, transport equipment, and the like are required. Further, when the color of the colored pipe is changed or adjusted, various adjustments have to be made from the stage of producing the colored pellets, which requires a great deal of labor and time.

Accordingly, an object of the present invention is to provide a method capable of easily producing a molded article comprising a polyolefin colored resin having a desired color with a simple equipment configuration.

[0006]

In order to achieve the above object, a method for producing a polyolefin-colored resin molded article of the present invention comprises the steps of: charging a polyolefin raw material and a pigment into a high-speed dispersion twin-screw kneader; Kneading while heating to a predetermined temperature in a kneading machine, characterized in that it is introduced into a die to obtain a molded product of a predetermined shape made of a polyolefin colored resin, and further, between the high-speed dispersion biaxial kneader and the die, A gear pump is provided for feeding the resin kneaded by the high-speed dispersing twin-screw kneader to the die.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic view showing an example of an extrusion equipment for carrying out the method for producing a polyolefin colored resin molded article of the present invention. This production facility is for producing a colored pipe made of polyolefin, for example, a colored pipe P made of polyethylene, and includes a high-speed dispersing twin-screw kneader 11, a gear pump 12, and a base 13.

The high-speed dispersing twin-screw kneader 11 mounts a kneading desk and a conveying screw on two shafts provided in parallel in a barrel, and rotates both shafts in the same direction at a high speed to knead. It is formed so that the temperature can be adjusted by a cooling pipe, a jacket, a heater, or the like provided on the outer periphery of the barrel. This high-speed dispersion twin-screw kneader 11
By appropriately setting the state of attachment of the desk and the screw to the shaft, the raw material input from the raw material input section 14 can be effectively kneaded and dispersed and sent out from the head 15.

The production of the colored pipe P made of polyethylene using the high-speed dispersing twin-screw kneader 11 is performed by appropriately supplying
For example, using a capacity type feeder or a weight type feeder, feed the polyethylene raw material and the pigment, and further, if necessary, an appropriate additive into the raw material input unit 14 at a predetermined ratio,
While adjusting the temperature so that the temperature inside the barrel is close to the melting temperature of the resin, high-speed kneading and dispersion at several hundred revolutions per minute are performed, and the molten resin in a state where the pigment is sufficiently dispersed is transferred to the head 1.
5 and pressurized to a predetermined pressure by the gear pump 12 and sent to the base 13, whereby the colored pipe P formed into a predetermined shape can be obtained from the base 13.

[0010] As described above, the pigment can be uniformly dispersed in the resin by kneading and dispersing the resin raw material and the pigment at high speed by the high-speed dispersing twin-screw kneader 11. A colored pipe P having no defect can be obtained. Further, since it is not necessary to manufacture colored pellets as intermediates as in the related art, the steps and equipment can be greatly simplified, and the manufacturing cost of the colored pipe P can be reduced. Further, the color of the colored pipe can be changed or adjusted in the raw material input section 14 of the high-speed dispersing twin-screw kneader 11.
Can be adjusted simply by changing the ratio of the resin raw materials and pigments to be added to the product, so that color adjustment can be performed more easily and in a shorter time than in the past, and the product with the desired coloring can be stabilized. Can be obtained reliably.

When the discharge pressure of the resin in the high-speed dispersing twin-screw kneader 11 is sufficiently high, it is also possible to omit the gear pump 12 and directly supply the resin from the head 15 to the base 13 for extrusion molding. . Further, the kind of the polyolefin or the pigment used as a raw material is arbitrary, and can be appropriately selected according to the intended molded product.

[0012]

As described above, according to the method for producing a polyolefin-colored resin molded article of the present invention, a polyolefin-colored resin molded article having no color unevenness or defects, for example, a colored polyethylene pipe can be easily and at low cost. can do. Further, the change and adjustment of the color can be easily and reliably performed.

[Brief description of the drawings]

FIG. 1 is a schematic view showing one example of an extrusion equipment for carrying out the method of the present invention.

[Explanation of symbols]

11 high-speed dispersing twin-screw kneader, 12 gear pump, 13
Base, 14: Material input section, 15: Head, P: Colored pipe

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) C08K 3/00 C08K 3/00 C08L 23/00 C08L 23/00 // B29K 23:00 B29K 23:00 B29L 23:00 B29L 23:00 F-term (reference) 4F070 AA12 AE04 FA03 FB06 FC04 4F071 AA14 AE09 AH19 BA01 BB06 BB13 BC05 BC07 4F201 AA03 AB12 AG08 BA01 BC01 BC13 BC37 BD05 BK02 BK13 BK26 BK31 BQ09 BQ20 ABK13A KL23 KL94 KM15 4J002 BB001 BB031 FD096 GT00

Claims (2)

[Claims] 1. A polyolefin raw material and a pigment are charged into a high-speed dispersing twin-screw kneader, kneaded while heating to a predetermined temperature in the high-speed dispersing twin-screw kneader, and introduced into a die to form a predetermined shape comprising a polyolefin colored resin. A method for producing a polyolefin-colored resin molded product, characterized by obtaining a molded product of (1). 2. The polyolefin coloring according to claim 1, wherein a gear pump for feeding the resin kneaded by the high-speed dispersing twin-screw kneader to the die is provided between the high-speed dispersing twin-screw kneader and the die. Manufacturing method of resin molded product.