JPH04245965A - Hard shaped article of fiber - Google Patents

Abstract

PURPOSE:To obtain a hard shaped article of fiber useful as a substitute for molded article of polyurethane cushion, having small change in shape and excellent shapability. CONSTITUTION:A shaped article of highly entangled fibers is obtained by blending crimped staple fibers of hollow fibers of polyethylene terephthalate with staple fibers of hollow core-sheath type conjugate yarn comprising a core component polymer of polyethylene terephthalate and a sheath component polymer of polyhexamethylene terephthalate/polyethylene terephthalate-based copolymer polyester as heat binder fibers and entangling and entangled points of the fibers of the shaped article are at least partially fused and fixed with the sheath component polymer of the heat binder fibers to give a hard shaped article of fiber having <=20% compression ratio at 0.12-0.45g/cm<3> apparent density and >=10mm thickness under 1.0kg/cm<2> load.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a firm cotton molded article which is a substitute for a polyurethane cushion molded article and which exhibits little change in shape.

0002

[Prior Art] Conventionally, laminated composites of fabrics such as non-woven fabrics, sheets of polybutylene terephthalate knitted fabrics, non-woven fabrics, etc., and plastic sheets have been deep-drawn to produce car seats and automobile interior materials. 1986-6
No. 284 discloses that high melting point fibers such as polyester fibers are mixed with low melting adhesive fibers such as core-sheath type composite fibers using low melting point components whose melting point is 30°C or more lower than the core, and the mixture is rolled into a cotton shape and processed by needle processing, etc. It has been disclosed in Japanese Utility Model Application Publication No. 81884/1984, Japanese Patent Application Publication No. 6865/1998, and Japanese Patent Application Publication No. 2-6865 that hard felt-like cotton obtained by entanglement treatment and heat treatment can be used as a cushion body for beds and seats or as a base material for interior decoration. -15405
It has been proposed in Publication No. 0, etc.

0003

[Problems to be Solved by the Invention] Conventionally proposed hard felt-like cotton cushion bodies or interior materials for beds and seats do not have sufficient fiber density and are inferior in form stability and compression properties. The elasticity of the body is low, and there are problems such as buckling even with slight bending. Furthermore, even in drawing forming, it is difficult to obtain well-organized curvature portions.

SUMMARY OF THE INVENTION The object of the present invention is to provide a firm cotton molded article that is less susceptible to changes in shape and has excellent moldability as an alternative to polyurethane cushion molded articles.

[0005]

[Means for Solving the Problems] The present invention provides short fibers of crimped polyester hollow fibers having a single fineness of 6 to 80 deniers and polyethylene terephthalate as a core component polymer.
A molded body of a fiber entangled body consisting of short fibers of polyester hollow core-sheath type composite fibers having a single denier of 3 to 50 deniers and a polyester having a melting point of 230°C or less as a sheath component polymer, wherein the fibers of the molded body are At least a part of the contact point is fused by the sheath component polymer of the core-sheath composite fiber, and when the apparent density is 0.12 to 0.45 g/cm3, the thickness is 10 mm or more, and the load is 1.0 Kg/cm2. Compression rate is 20%
This is a solid cotton molded article having the following characteristics.

The polyester hollow fibers constituting the firm cotton molded article of the present invention are, for example, polymers selected from polyethylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polyarylate, etc., in which 80 mol% or more is ethylene terephthalate. polyester hollow fibers that are spun, stretched, and mechanically crimped, or a combination of two types of polyesters with different thermal properties from the above polymers, composite spun side-by-side, stretched, and as required. This is a polyester hollow latent crimpable composite fiber obtained by mechanical crimping. The fineness and fiber cross-sectional shape of these polyester hollow fibers are determined depending on the desired use, but usually the fineness is in the range of 6 to 80 deniers and the hollow ratio is in the range of 7 to 25%. Hollow irregular cross-section fibers of square or multilobal shape are used.

[0007] In addition, since the polyester hollow core-sheath type composite fiber is used as a thermal binder fiber, the sheath component polymer of the core-sheath type composite fiber has a melting point of the main fiber constituting the fiber entanglement and a core component polymer. at least 30°C below the melting point of
It is a polyester polymer with a low melting point, and generally contains 20 to 47 copolymerized polyesters with a melting point of 230°C or less, such as ethylene isophthalate, butylene isophthalate, or hexamethylene terephthalate.
A low melting point polymer selected from polybutylene terephthalate, polypentamethylene terephthalate, polyhexamethylene terephthalate, polybutylene isophthalate, etc. can be used. On the other hand, the core component polymer is preferably polyethylene terephthalate containing 80 mol% or more of ethylene terephthalate. Then, the core component polymer and the sheath component polymer can be spun by a normal core-sheath composite spinning method, drawn, and mechanically crimped to form a polyester hollow core-sheath composite fiber. The fineness and fiber cross-sectional shape of this polyester hollow core-sheath type composite fiber are determined depending on the intended use, but usually the fineness is in the range of 3 to 50 deniers and the hollow ratio is in the range of 7 to 25%.
In addition to hollow circular cross-sectional fibers, hollow irregular cross-sectional fibers having a polygonal or multilobal cross-sectional shape are used.

[0008] Next, the method for producing a hard cotton molded article is to use short fibers of polyester hollow fibers and polyester hollow core-sheath composite fibers each having a fiber length of 25 to 80 mm, with a weight ratio of polyester hollow fibers of 85 to 45 mm. Mix within % range. If the mixing ratio is too high, the compression rate will be high and the shape retention will be poor, while if the mixing ratio is low, the shape retention will be good but it will be hard, have a low compressive elasticity, and will be prone to buckling and have a poor texture. Furthermore, if you want to increase the bulkiness of the molded product and obtain good cushioning properties, use polyester hollow latent crimped composite fibers or crimped polygonal or multilobal hollow irregular cross-section fibers. use. In addition, when trying to increase the fiber density of the molded product to obtain a molded product that is hard and has high compressive elasticity, high-shrinkage polyester hollow fibers or high-shrinkage polyester hollow fibers and polyester hollow latent crimp composite fibers can be used. It is preferable to use blended cotton. After the above fibers are mixed at a predetermined fiber ratio, a fiber web with an average weight of 30 to 200 g/m2 is formed by a normal dry method, and the fiber webs are laminated to a predetermined weight or thickness to obtain a molded product. Then, it is made into a fiber entangled nonwoven using a fiber entangled treatment method such as a needle punch method, a stitch bond method, or a high-pressure water treatment method.

[0009] Next, the fiber-entangled nonwoven fabric is heat-treated to give shrinkage to the shrinkable fibers, to cause the latent crimpable fibers to develop spontaneous crimp, and to increase the sheath component weight of the core-sheath composite fibers, which are thermal binder fibers. Fusion and fixation between fibers is performed by coalescence. The heat treatment is carried out in hot water at 70 to 135°C, in a wet heat or dry heat atmosphere at 80 to 185°C, under one condition or a combination of two or more conditions. In addition, fiber entangled nonwoven fabrics or fiber entangled nonwoven fabrics that have been heat-treated in advance can be laminated one or more layers and hot press molded with a heated mold or press plate, or hot press processed with heated rolls to form a fiber entangled product. A molded article is obtained in which at least some of the contact points of the fibers are fused and fixed with the sheath component polymer of the core-sheath type composite fiber. The apparent density of this molded body is 0.12 to 0.45g
/cm3, thickness is 10mm or more, load 1.0Kg/c
The compression ratio at m2 shall be 20% or less. As a result, a solid cotton molded article with good elasticity and little change in shape can be obtained, and it can also be useful as a cushion body as an alternative to polyurethane.

[0010] In addition, the hard cotton molded article of the present invention can be prepared by adding a flame retardant, a flame retardant, or
Treatment with insect repellents, fungicides, heat stabilizers, colorants, aromatics, etc., resin processing, or application of a resin film may also be carried out.

Next, the solid cotton molded article of the present invention will be explained with reference to the drawings. Figure 1 is a schematic cross-sectional view of polyester hollow fibers constituting a solid cotton molded body, and Figure 1 (1) is a hollow circular cross-section fiber;
(2) and (3) are hollow irregular cross-section fibers, and Figure 1 (4) is a hollow latent crimpable composite fiber in which two types of polyester components 1 and 2 with different thermal properties are joined side-by-side. , 1 is a polyester component I, 2 is a polyester component II, and 3 is a hollow part. Figure 2 is a schematic cross-sectional view of a polyester hollow core-sheath type composite fiber which is a thermal binder fiber constituting a hard cotton molded body, and Figure 2 (1) is a hollow circular cross-section fiber;
2 (2) and (3) are hollow irregular cross-section fibers, 3 is a hollow portion, 4 is a polyethylene terephthalate core component, and 5 is a low melting point polyester sheath component.

FIG. 3 is a schematic cross-sectional view of a solid cotton molded article, in which at least one of the fiber intersections of the fiber entangled body is formed by mixing and entangling polyester hollow fibers 7 and polyester hollow core-sheath composite fibers 8. This is a hard cotton molded body 6 whose portions are fused and fixed 9.

[0013]

[Examples] Next, the present invention will be explained with examples. In addition, parts and percentages in the examples refer to weight unless otherwise specified.

Example 1 Machine crimped fineness 40dr,
65 parts of polyethylene terephthalate hollow fiber with a hollow ratio of 14.7% and a fiber length of 55 mm, as a thermal binder fiber,
50 parts of polyethylene terephthalate having an intrinsic viscosity [η] = 0.85 as a core component and 50 parts of hexamethylene terephthalate/ethylene terephthalate copolyester (melting point 135°C) as a sheath component were spun into a hollow core-sheath type composite fiber, drawn, and mechanically wound. A fiber web with an average weight of 75 g/m2 obtained by blending 35 parts of a polyester hollow core-sheath type composite fiber with a shrinked fineness of 18 dr, a hollow ratio of 17.4%, and a fiber length of 51 mm and passing it through a card and a random webber is cross-woven. They were laminated by a wrapping method and pre-needled to obtain a nonwoven fabric having an average weight of 769 g/m2. Laminate two sheets of this nonwoven fabric, and alternately use a regular needle with a needle size of 36 from both sides of the nonwoven fabric for a total of 180 needles.
A needle punch of 1/cm2 was performed. Then temperature 1
It was treated in hot air at 50°C and pressed with a calendar press roll provided at the exit of the heat treatment machine to obtain a sheet-like molded body made of a smooth fiber-entangled nonwoven fabric with fibers fused and fixed.

[0015] This sheet-like molded product has an apparent density of 0.14
9g/cm3, thickness 10.3mm, load 1.0Kg/c
Compression rate at m2 is 6.5%, width 25mm - length 20
Even when holding both ends of the 0 mm rectangular test piece and bending it, it was a strong sheet-like molded product that did not buckle.

[0016] This sheet-like molded product was suitable as a cushion body to be used by placing it on a spring of a seat, bed, or the like. Furthermore, this cushion body has been subjected to practical tests such as temperature dependence and thermal deterioration acceleration tests.
Unlike polyurethane cushion bodies, the molded body did not have large temperature dependence and was durable and stable.

Comparative Example 1 In place of the polyester hollow core-sheath composite fiber as the thermal binder fiber of Example 1, a normal polyester core-sheath composite fiber having a fineness of 18 dr and a fiber length of 51 mm was used. A sheet-like molded body made of a smooth fiber-entangled nonwoven fabric with fibers fused and fixed by the same processing was obtained.

[0018] This sheet-like molded product has an apparent density of 0.17
4g/cm3, thickness 8.85mm, load 1.0Kg/c
Compression rate at m2 is 4.4%, width 25mm - length 20
When a 0 mm rectangular test piece was bent by holding both ends, buckling occurred in the middle, and although the hardness of the molded product increased, the sheet-like molded product was weak.

Example 2 Mechanically crimped polyethylene terephthalate with a fineness of 30 dr, a hollow ratio of 15.3%, and a fiber length of 51 mm/8 mol%
40 parts of Zide-by-side type hollow latent crimp composite fiber of isophthalate-modified polyethylene terephthalate, mechanically crimped fineness 40dr, hollowness ratio 14.7%,
Polyethylene terephthalate hollow fiber 3 with fiber length 55mm
A fiber web with an average weight of 77 g/m2 obtained by mixing 0 part of polyester core-sheath type composite fiber of Example 1 and passing it through a card and a random web was laminated by a cross-wrapping method, and pre-needled to obtain an average A nonwoven fabric weighing 792 g/m2 was obtained. Laminate two sheets of this nonwoven fabric, and alternately use a regular needle with a needle size of 36 from both sides of the nonwoven fabric for a total of 1
After performing 80 needle punches/cm2, the temperature was 95.
It was treated in hot water at 0.degree. C. to develop spontaneous crimp, and then dried and free heat treated in a tenter heat treatment machine to obtain a sheet-like molded article made of a fiber-entangled nonwoven fabric in which the fibers were fixed. This sheet-like molded product was punched out into a certain shape and size for an automobile seat, and heated and press-molded using a mold to produce a cushion body for an automobile seat.

[0020] This cushion body has an apparent density of 0.206
g/cm3 and an average thickness of 10.4 mm, the molded product was strong, had excellent compressive elasticity, and had a stable shape. In particular, this cushion body was suitable as a cushion body for automobile seats because it did not have large temperature dependence like polyurethane cushion bodies, had appropriate hardness, and the change in hardness over time was almost negligible.

[0021]

[Effects of the Invention] The firm cotton molded article of the present invention has excellent compression properties and elastic properties, and is a product with good shape stability. In particular, it can be used as an alternative to applications where there is concern about the generation of toxic gases due to thermal decomposition of polyurethane, such as seat cushions, automobiles, etc.
It is widely applied to interior and exterior materials for buildings and furniture, insulation materials, toys, etc.

[0022]

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of polyester hollow fibers constituting the firm cotton molded article of the present invention.

FIG. 2 is a schematic cross-sectional view of a polyester hollow core-sheath type composite fiber as a thermal binder fiber of the present invention.

FIG. 3 is a schematic cross-sectional view of the solid cotton molded article of the present invention.

[Explanation of symbols]

1 Polyester component I 2 Polyester component II 3 Hollow part 4 Polyethylene terephthalate core component 5 Low melting point polyester sheath component 6 Hard cotton molded product 7 Polyester hollow fiber 8 Polyester hollow core-sheath composite fiber 9 Fiber fusion part

Claims (1)

[Claims] Claim 1: Short fibers of crimped polyester hollow fibers with a single fineness of 6 to 80 deniers, polyethylene terephthalate as a core component polymer, and polyester with a melting point of 230°C or less as a sheath component polymer, with a single fineness of 3 to 80 deniers. A molded article of a fiber entangled body consisting of short fibers of a 50-denier polyester hollow core-sheath composite fiber, wherein at least a portion of the contact points of the fibers of the molded article are made of the sheath component polymer of the core-sheath composite fiber. The apparent density is 0.12 to 0.45.
g/cm3, load 1.0K for thickness 10mm or more
A solid cotton molded article having a compression ratio of 20% or less in g/cm2.