JP7112769B2 - METHOD FOR REINFORCING WALL OF RESIN CONTAINER - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method of reinforcing a resin container by adhering fabric to the wall of the container.

Conventionally, the container is reinforced by adhering fabric to the outside or inside of the wall of the container made of resin, or by inserting the fabric into the wall. As the fabric, a woven fabric, a knitted fabric, a multiaxial sheet, or the like is used. As such a reinforcing material made of fabric, a material having yarns made of core-sheath type composite fibers as constituent yarns is used. The core-sheath type conjugate fiber has a core component made of a high melting point polymer and a sheath component made of a low melting point polymer. And since only the sheath component can be softened or melted and can be fused to the wall of a resin container, it is used as a constituent fiber of a fabric reinforcing material.

High-melting point polymers such as polyamide, polyester, polyolefin, polyurethane, polycarbonate, acrylic, polyphenylene ether and polyvinyl alcohol are used as the core component of the core-sheath type composite fiber used for the fabric reinforcing material, and the sheath component is Low-melting point polymers such as polyethylene, polypropylene and ethylene-propylene copolymers are used (Patent Document 1, Claims 1 to 3). That is, it is known that various polymers can be used as the core component as long as they are high-melting polymers, and the use of olefinic polymers, which are well compatible with resins and have excellent adhesiveness, as the sheath component.

However, core-sheath type conjugate fibers used as constituent fibers of reinforcing materials are required to have high strength and elongation. In particular, high strength and elongation are required for the core component, which remains in a fibrous form after being adhered to the wall of the resin container. In order to increase the strength and elongation of the fiber, the fiber may be subjected to a drawing treatment. However, in the case of the core-sheath type conjugate fiber, the core component and the sheath component separate when subjected to a drawing treatment, and the sheath component is separated when the yarn made of the core-sheath type conjugate fiber is used for weaving or knitting. There is a drawback that it is difficult to have the sheath component uniformly present in the fabric due to detachment or cutting. Moreover, even if the core-sheath type conjugate fiber in which the core component and the sheath component are separated is adhered to the wall of a container or the like, there is a drawback that strong adhesion cannot be realized.

Japanese Patent Application Laid-Open No. 2003-193332

An object of the present invention is to provide a resin container wall by using a woven fabric in which the core component and the sheath component are difficult to separate even when the core-sheath type conjugate fiber is subjected to a drawing treatment, and the sheath component is uniformly present in the woven fabric. To provide a method for firmly reinforcing the

The present invention solves the above problems by using a specific polymer for the core component and the sheath component and performing a specific treatment. That is, the present invention comprises a step of producing a multifilament yarn comprising a core-sheath type composite fiber having a core component made of polyamide and a sheath component made of maleic acid-modified polyolefin and high-density polyethylene by a composite melt spinning method, and the multifilament yarn. After cooling the yarn, it is subjected to drawing treatment under heating to produce a drawn multifilament yarn, weaving a woven fabric using the drawn multifilament yarn as warp and weft, and making the woven fabric from a resin. Reinforcement of the wall of a resin container characterized by comprising a step of stretching the surface of the wall of the container, heating and pressurizing, and bonding by softening or melting only the sheath component of the core-sheath type composite fiber. It is about the method .

First, a polyamide is prepared as a core component. Nylon 6, nylon 66, or the like can be used as the polyamide. The melting point of polyamide varies depending on the type, but is generally 170°C to 270°C. By using polyamide as the core component, excellent chemical resistance and impact resistance can be obtained, and the core component can have high strength and high elongation by drawing treatment. In addition, a maleic acid-modified polyolefin is prepared as a sheath component. Maleic acid-modified polyolefin is obtained by adding maleic acid (including maleic anhydride) to the side chains of polyolefin. Maleic acid-modified polyethylene and maleic acid-modified polypropylene can be used as the maleic acid-modified polyolefin. The melting point of the maleic acid-modified polyolefin also varies depending on the type, but is generally 110 to 160° C., which is lower than the melting point of the polyamide. By using a maleic acid-modified polyolefin as the sheath component, the compatibility with the adherend is improved and the adhesiveness is improved.

High-density polyethylene is added to the maleic acid-modified polyolefin that is the sheath component. The amount of high-density polyethylene added is about 50 to 150 parts by weight with respect to 100 parts by weight of maleic acid-modified polyolefin. The reason for adding high-density polyethylene is to give the sheath component two melting points to improve the fusion bondability. It is also for facilitating composite melt spinning by adjusting the melt flow rate of the sheath component.

A method in which a core component and a sheath component are introduced in a molten state into a spinning device having a plurality of composite melt spinning holes, and the core component and the sheath component are discharged from the heated composite melt spinning hole (that is, a composite melt spinning method ) to obtain a core-sheath type composite fiber. A multifilament yarn is obtained by arranging the core-sheath type composite fibers obtained from the composite melt spinning holes. It is preferable to adjust the melt flow rates of the core component and the sheath component within a certain range in order to continuously discharge the core component and the sheath component from the composite melt spinning hole and coat the core component well with the sheath component. . Specifically, it is preferable to set the melt flow rate of the core component within the range of 5 to 40 g/10 minutes and the melt flow rate of the sheath component within the range of 15 to 65 g/10 minutes. In particular, within this range, it is preferable to make the melt flow rate of the sheath component higher than the melt flow rate of the core component to enhance the fluidity of the sheath component. The melt flow rate was measured under a load of 2.16 kg at a temperature of 270° C., which is close to the temperature during composite melt spinning.

The resulting multifilament yarn is cooled and wound up. Also, after cooling, an oil agent may be applied to the multifilament yarn. By applying an oily agent, it is possible to improve winding properties, unwinding properties, weaving properties, knitting properties, and the like. After cooling, the multifilament yarn is drawn under heat to obtain a drawn multifilament yarn. Examples of the heating method include a method of blowing superheated steam onto the multifilament yarn, a method of blowing hot air, and the like. The heating temperature is preferably a temperature that promotes crystallization of the core component, and is about 100 to 200°C. Of course, even if superheated steam or hot air is blown onto the multifilament yarn, the temperature of the multifilament yarn does not immediately reach the temperature of the superheated steam or hot air. . Stretching takes place between two pairs of rollers. For example, after introducing a multifilament yarn between a pair of first rollers heated to about 100° C., this multifilament yarn is introduced between a pair of heated second rollers having a faster rotation speed than the first roller. It is done by By providing a rotation speed difference between the first roller and the second roller, the film can be stretched at an arbitrary ratio. For example, when the rotation speed of the first roller is X rpm, if the rotation speed of the second roller is 2 X rpm, the film is stretched at a draw ratio of 2 times. In the present invention, the draw ratio is preferably 3 to 7 times, most preferably 4 to 6 times.

In the obtained drawn multifilament yarn, the fineness of the core-sheath type conjugate fibers is about 5 to 10 decitex, and the number of the core-sheath type conjugate fibers is about 100 to 300. Therefore, the total fineness of the drawn multifilament yarn is about 500-3000 decitex. The drawn multifilament yarn is used for warp and weft and woven to obtain a woven fabric. A conventionally known weave such as a plain weave, a twill weave, or a satin weave may be used for the weave of the woven fabric. Since the yarns constituting these fabrics are made of core-sheath type conjugate fibers, only the sheath component may be softened or melted to fuse the yarns to prevent misalignment. . Of course, the core-sheath type conjugate fibers forming each thread may also be fused to each other to impart rigidity to the fabric.

The fabric made of the fabric obtained by the above method is stretched on the surface of the wall of the resin container, heated and pressurized, and only the sheath component of the core-sheath type composite fiber is softened or melted and bonded to the resin. The walls of the container can be reinforced.

In the woven fabric used in the method of the present invention, the core component and the sheath component of the core-sheath type conjugate fibers constituting the woven fabric are not separated, and the sheath component is uniformly present in the woven fabric. Therefore, by adopting the method according to the present invention, the woven fabric is strongly adhered to the wall of the resin container, and thus has an excellent reinforcing effect.

Example 1
As a core component, nylon 6 having a melting point of 225° C. and a melt flow rate of 10.6 g/10 minutes was prepared. As a sheath component, the following mixed resin was prepared. That is, 40 parts by weight of high-density polyethylene having a melting point of 131° C. and a melt flow rate of 55.8 g/10 minutes, and 60 parts by weight of maleic acid-modified polyethylene having a melting point of 122° C. and a melt flow rate of 25.9 g/10 minutes. A uniformly mixed mixed resin was prepared. Then, a core-sheath type composite spinneret having a hole diameter of 0.5 mm and 192 holes was installed in the composite melt spinning device, and the core component:sheath component was adjusted to 2:1 (weight ratio) at a nozzle temperature of 265 ° C. Both were supplied, and 192 core-sheath type conjugate fibers were spun. Then, it is passed through a heating cylinder with a length of 20 cm at a temperature of 300 ° C. provided directly under the spinneret, and then, using a horizontal cooling device, cold air is blown at a temperature of 16 ° C. and a speed of 0.8 m / sec. The core-sheath type composite fiber was cooled. After cooling, an oil agent was applied to the surface of the core-sheath type conjugate fiber, and the multifilament yarn in which 192 core-sheath type conjugate fibers were aligned was wound with a winding roller.

The multifilament yarn was unwound from the take-up roller, introduced into a pair of first rollers heated to 100°C, and further introduced into a pair of second rollers heated to 110°C. Between the first roller and the second roller, the multifilament yarn was drawn at a draw ratio of 4.8 times while spraying superheated steam at a temperature of 300° C. and a pressure of 0.3 MPa using a steam processor. After drawing, relaxation treatment and relaxation treatment were performed by a conventional method to obtain a drawn multifilament yarn of 1670 decitex/192 filaments.

Example 2
A drawn multifilament yarn was obtained in the same manner as in Example 1, except that the mixing ratio of the mixed resin was 30 parts by weight of high-density polyethylene and 70 parts by weight of maleic acid-modified polyethylene.

Reference example 1
A drawn multifilament yarn was obtained in the same manner as in Example 1, except that 100 parts by weight of maleic acid-modified polyethylene was used instead of the mixed resin.

Comparative example 1
A drawn multifilament yarn was obtained in the same manner as in Example 1, except that 100 parts by weight of high-density polyethylene was used instead of the mixed resin.

A photograph of the cross section of the drawn multifilament yarn obtained in Example 1 observed with an optical microscope is shown in FIG. 1, and the cross section of the drawn multifilament yarn obtained in Comparative Example 1 was observed with an optical microscope. is shown in FIG. As is clear from a comparison of FIGS. 1 and 2, in the core-sheath type conjugate fiber constituting the drawn multifilament yarn obtained in Example 1, the core component and the sheath component were hardly separated, whereas In the core-sheath type conjugate fiber obtained in Comparative Example 1, separation between the core component and the sheath component is remarkable.

Plain woven fabrics were woven using the drawn multifilament yarns obtained in Examples as warp and weft yarns, and when this was adhered to the wall of a resin container by heating and pressing, the fabric firmly adhered to the wall of the resin container. It adhered and could be suitably used as a reinforcing material.

1 is a photograph of a cross section of the drawn multifilament yarn obtained in Example 1, observed with an optical microscope. 4 is a photograph of a cross section of the drawn multifilament yarn obtained in Comparative Example 1, observed with an optical microscope.

Claims (1)

a step of manufacturing a multifilament yarn comprising a core-sheath type composite fiber having a core component made of polyamide and a sheath component made of maleic acid-modified polyolefin and high-density polyethylene by a composite melt spinning method;
a step of cooling the multifilament yarn and then subjecting the multifilament yarn to drawing treatment under heating to produce a drawn multifilament yarn;
a step of weaving a woven fabric using the drawn multifilament yarns as warps and wefts; A method for reinforcing a wall of a resin container, comprising a step of softening or melting a chisel to bond.

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