JPH0333217A - Thermo-binder fiber - Google Patents

Abstract

PURPOSE:To provide the subject fiber composed of thermoplastic polymers having respective specific melting points as core and sheath components, containing specific amounts of pigment in the core component, the sheath component and the fiber having the sheath-core conjugate structure and effective in suppressing the color shading in dyeing and imparting a masking effect, etc., to a non-woven fabric, etc. CONSTITUTION:The objective fiber containing a total pigment content of 0.5-10wt.% is a pigment-containing sheath core conjugate fiber composed of (A) a core component consisting of a thermoplastic polymer (e.g. polyethylene terephthalate) having a melting point of >=150 deg.C and containing 0-5wt.% of pigment based on the core component and (B) a sheath component consisting of a thermoplastic polymer (e.g. polyethylene) having a melting point lower than that of the core component by >=30 deg.C and containing 0-50wt.% of pigment. If necessary, the fiber is further incorporated with an antioxidant, a stabilizer, etc.

Description

[Detailed description of the invention] [Industrial application field]

The present invention is a thermal binder fiber that is mixed into a fiber aggregate such as a nonwoven fabric, a woven fabric, or a knitted fabric and used to bond and fix the fibers. , relates to mature binder fibers that are suitably used to impart excellent hiding effects.

[Conventional technology]

Conventionally, many proposals have been made for thermal binder fibers. For example, a peelable composite fiber of polyethylene and polypropylene is disclosed in Japanese Patent Publication No. 52-4653, with a first component consisting of crystalline polypropylene, and a second component consisting of a polymer mixture of polyethylene, ethylene-vinyl acetate copolymer, or its saponified product, and polyethylene. Heat-fusible composite fibers arranged in parallel type or sheath-core type
According to Japanese Patent Publication No. L82, Japanese Patent Publication No. 55-17807, Japanese Patent Publication No. 55-26209, and Japanese Patent Publication No. 55-27174, heat-melting anhydrous polyvinyl alcohol and a hydrophobic thermoplastic resin are mixed and melt-spun. According to Japanese Patent Publication No. 5g-9163, the obtained thermoplastic fibers are used as binder fibers, and linear low density polyethylene (^) is used as a sheath component.
JP-A-63-243324 discloses a core-sheath type heat-adhesive fiber containing crystalline polypropylene and (^) mud as a core component, and further laminates four or more layers of thermoplastic polyester and low-softening thermoplastic polyester. A self-fusing polyester composite fiber has been proposed in Japanese Patent Application Laid-Open No. 63-243325.

[Problem to be solved by the invention]

However, in conventional manufacturing techniques for core-sheath type composite fibers, there have been almost no proposals for actively adding pigments to improve the concealment properties of textile products such as nonwoven fabrics that are finally obtained. In particular, transparent thermoplastic polymers have been used as polymer materials in conventional thermal binder fibers.
There were some disadvantages depending on the application. For example, in the case of non-woven fabrics for sanitary materials, since the constituent fibers of the non-woven fabric are mainly synthetic fibers, they are highly transparent, which often causes discomfort as the internal absorbent material can be seen through. was there. In addition, because the main fiber and thermal binder fiber components of the fiber aggregate have different dyeing behavior, the product has the disadvantage of causing uneven color and gloss. Sufficient consideration has not been given to improving the degree of cleanliness and increasing the sense of cleanliness by improving the temperature of 0 degrees. An object of the present invention is to provide a thermal binder fiber that eliminates the drawbacks of the conventional thermal binder fibers as described above, suppresses color unevenness and gloss unevenness of fiber aggregates, and provides an excellent hiding effect. be.

[Means to solve the problem]

The present invention provides a thermal binder fiber having a pigment-containing core-sheath type composite structure, in which the core component is a thermoplastic polymer having a melting point of 150°C or higher, and the sheath component is a thermoplastic polymer having a melting point at least 30°C lower than the melting point of the core component. , the pigment is contained in the sheath component of the thermal binder V & fiber in an amount of 0 to 5% by weight, the core component thereof as contained in an amount of 0 to 5% by weight, and the total pigment content in the thermal binder fiber is 05 to 10% by weight. It is a thermal binder@fiber characterized by the following. The thermal binder fiber of the present invention has a two-sheath type composite structure in which the core component is a thermoplastic polymer having a melting point of 150° C. or higher and the sheath component is a thermoplastic polymer having a melting point at least 30'C lower than the melting point of the core component. Thermoplastic polymers include, for example, polyesters such as polyethylene terephthalate, polybutylene terephthalate, ethylene terephthalate copolymers with at least 85 mole percent ethylene terephthalate, 6-nylon, 6-row nylon, 610-nylon, 11-nylon, 12 - A thermoplastic polymer selected from the group of polyamides such as nylon, polyolefins such as polyvinyl chloride and polypropylene. The thermoplastic polymer contains 0 to 5% by weight of pigment based on the weight of the polymer. The pigment content is determined by the form or fineness of the final fiber and the thickness (fabric weight) of the fiber aggregate. That is, when the fineness is small and the thickness of the fiber aggregate is thin, the amount added is increased. However, if the amount of pigment added exceeds 5% by weight, the fiber performance may deteriorate and the physical properties of the fiber aggregate may be impaired. Furthermore, if the amount of pigment added to the core component is small, the hiding effect of the fiber aggregate will be reduced, so in that case, it is preferable to increase the amount of pigment added to the nitric acid. Further, the thermoplastic polymer of the sheath component is a polymer having a melting point at least 30°C lower than the melting point of the thermoplastic polymer of the core component, for example, polyethylene, polypropylene, ethylene and propylene, butene, octene, etc. copolymers, polyolefins such as ethylene vinyl acetate copolymers and ethylene vinyl alcohol copolymers, and polyesters such as polyhexamethylene terephthalate, polyhexamethylene butylene terephthalate, polyhexamethylene terephthalate isophthalate, and polyethylene terephthalate isophthalate. at least one thermoplastic polymer selected from the group consisting of thermoplastic polymers; Particularly preferred polymers have a measurement temperature of 190
Melt flow rate at °C ~ 40g/10
It is a highly fluid polymer. If the melting temperature of the sheath component polymer becomes high and the melt flow rate becomes a polymer, the adhesive strength will not be sufficient and the fixation between the fibers will not be sufficient. Therefore, the fiber aggregate becomes a fiber product with poor shape retention, which is not preferable. It is preferable that the thermoplastic polymer contains a pigment in order to impart a concealing effect without causing color unevenness or gloss unevenness during dyeing. Pigment content is 0-5% by weight
is within the range of The content of this pigment is determined by the form of the final fiber aggregate and its thickness (basis weight). That is,
If the thickness of the fiber aggregate is thin, increase the amount added. However, if the amount of pigment added exceeds 5% by weight, the binder effect between the fibers decreases and the physical properties of the fiber aggregate may be impaired. On the other hand, if the amount added is too small, the concealing effect cannot be sufficiently exerted, so in such a case, the amount added relative to the core component may be adjusted. In the present invention, as long as a good concealing effect is achieved, it is sufficient to mix the pigment in either the core or the sheath component, or in such a case, a relatively large amount of pigment may be added to one of the components. Therefore, care must be taken not to impair spinnability. Also, if you are trying to improve only the hiding effect, it is more efficient to add pigment to the sheath component, but on the other hand, the binder effect decreases and the texture and texture of the final fiber aggregate decreases. Therefore, it is desirable to appropriately select the addition method, amount, etc., depending on the required properties. In the present invention, it is necessary to add C to the total pigment content in the thermal binder fibers of 0.5 to 10% by weight, preferably 2 to 6% by weight. If the amount added is too small, the concealing effect will not be achieved, and even if it is too much, it will be 6! This tends to cause deterioration in physical properties, spinnability, etc. Moreover, the effect of the thermal binder of the present invention is that since it has a core-sheath structure, it is possible to change the color property by adding pigments of different colors to the core and sheath respectively. Furthermore, during the production of thermal binder fibers, additives are added to the core component and/or sheath component as necessary, such as antioxidants, ultraviolet absorbers, optical brighteners, stabilizers, etc. f: Additives may also be added. Pigments to be added to the thermal binder w&fiber of the present invention include:
It is preferable to use an opaque pigment in order to suppress uneven gloss and provide a concealing effect. The pigments used are, for example,
Select from inorganic pigments such as titanium dioxide, antimony oxide, carbon black, titanium yellow, iron oxides, cobalt oxide complexes, and other pigments, and organic pigments such as phthalocyanine and azo pigments according to the color tone of the desired textile product. at least one opaque pigment. Furthermore, titanium dioxide is preferable for textile products whose main purpose is to enhance the white skin and concealment effect and to suppress uneven gloss. Next, in the method for producing thermal binder fibers of the present invention, fibers are obtained by spinning using a conventional core-sheath type composite spinning device. The conjugate fiber obtained by spinning is subjected to treatments such as drawing and fixing by ordinary means to obtain a core-sheath type conjugate fiber having a single fiber w1 fineness of 1 to 10 deniers. The amount of the core component polymer in the core-sheath composite fiber is 35 to 65% by weight, and the number of core components may be 1 or 2 to 5. Further, the cross-sectional shape of the core component in the thermal binder fibers may be a normal circular shape, or the core fiber shape may have a modified cross-section in order to provide a concealing effect using light reflectivity. Examples of irregular cross-sectional shapes include elliptical, triangular, sea star, etc.
Examples of fiber aggregates to which the thermal binder fibers of the present invention can be applied include flat and polygonal types, such as woven fabrics, knitted fabrics, napped fabrics, and napped knitted fabrics. Fabrics, various nonwoven fabrics (fiber webs, fiber entangled nonwoven fabrics, stitch bonded nonwoven fabrics, fiber lumps, etc.),
This includes paper obtained from wet papermaking. The fibers constituting these fiber aggregates are thermoplastic fibers, regenerated fibers, and natural fibers made of a thermoplastic polymer having a melting point higher than the melting point of the sheath component of the thermal binder fibers by 30° C. or higher. For example, polyester 1m such as polyethylene terephthalate fiber, ethylene terephthalate copolymer fiber, polybutylene terephthalate fiber, polyamide fiber such as 6 nylon fiber, 6 row nylon fiber, 610-nylon fiber, 11-nylon fiber, 12-nylon fiber, These include chemical fibers such as regenerated cellulose fibers, polyvinyl alcohol fibers, and acrylic fibers, and animal and plant fibers such as cotton, hemp, silk, and wool. Further, when a composite fiber having a high degree of latent crimp ability is used as the thermoplastic fiber, it is possible to improve the bulkiness and length recovery property of the fiber aggregate finally obtained. The thermal binder fiber of the present invention suppresses uneven gloss, has a high hiding effect, and in some cases can obtain a fiber aggregate with excellent color properties.For example, it can be used as a waterproof fabric,
It is useful as a thermal binder fiber for high-density fabrics, nonwoven fabrics for clothing, nonwoven fabrics for interior decoration, thermal binder fibers for knitted fabrics, thermal binder fibers for glueless non-twisted yarns, etc.

【Example】

Next, implementation fJ4@ of the present invention will be explained using a specific example. Note that parts and percentages in the examples are by weight unless otherwise specified. Examples 1 to 4, Comparative Example 1 Titanium dioxide was added to the core component polymer at ■0% and ■1.5%.
, ■ 30%, ■ 4.5%, 07.0% (Comparative Example 1), 45 parts of polyethylene terephthalate (melting point 265°C) with [η] = 0.67, added to the sheath component polymer, Polyhexamethylene with 0.6% titanium dioxide added

[Non-terephthalate polyester (melting temperature 123-1.
55 parts (melt flow rate 32g/10 minutes at 28℃, measurement temperature 190℃) were spun at 290℃ and winding speed 1,000m/1 using a melt spinning machine equipped with a core-sheath type composite spinneret with one core. Spun for 1 minute, stretched at 75°C in a water bath,
After crimping, heat setting and cutting, fineness 2.5 dr.
, 5 types of thermal binder fibers r, n with a fiber length of 51 mm
1 m, ■ and V were obtained. Polyethylene terephthalate fiber a containing 35 parts of this thermal binder fiber and 1.0% titanium dioxide with a fineness of 2 dr.
651!1, carded it, and made a fibrous web with an average basis weight of 100 g/+a'' using Random Univer. This fibrous web was made into a fiber-entangled nonwoven fabric using a hydroentanglement method, and then treated with a pair of heated calenders. A nonwoven fabric with a smooth surface, a thickness of 0.37 mm, and an apparent density of about 0.27 g/C113 was prepared.
Concealability [Standard colored paper p, c, c, s, symbol 2/R-4, 5
Place the sample nonwoven fabric on the -9 (red) plate and place it under indoor light for 10 minutes.
Results of relative comparison of color visibility by human appraisers] and color unevenness [color unevenness of sample dyed with 2% OWF disperse dye]. The evaluation results are shown in Table 1. Evaluation symbol (): Best, ○: Good △: Fairly bad, There was almost no uneven color. Dresses were made using the nonwoven fabrics of each of these examples, and both white and dyed fabrics had good concealment properties, so they did not show through, and the products had an even gloss, a soft texture, and good drapability. Ta. Example 5 Melting point 265 with 2.5% carbon black added to core component
°Ca polyethylene terephthalate ([ηj=0.67)
50 parts of polyethylene with a melting point of 120°C (melt flow rate of 20g/10 min at 190°C) with 0.5% carbon black added to the sheath component and 50 parts of polyethylene with a core component of a flat irregular cross section. Using a composite spinneret, the fibers were spun at a spinning temperature of 285°C, drawn, crimped, and heat-set to obtain a core-sheath type composite fiber having two flat cores with a single fiber fineness of 2.5 dr. Ta. This fiber was cut into a fiber length of 51 cm and used as a stable fiber as a thermal binder fiber. 130 of these thermal binder fibers are blended with 70 parts of 6-nylon staple fibers with a single fiber fineness of 2 dr, and a fiber length of 51 mm, and a random web is made by passing through a card and a random univer, three sheets are laminated, and fiber entanglement treatment is performed. and then temperature 1
Heat treated in a heating zone at 35℃ and calendered to fix the fibers and smooth the surface, resulting in an average basis weight of 145g/m.
After forming a fiber-fixed nonwoven fabric with a thickness of 0.58+*s, it was dyed in wine color with a metal complex dye, but the color unevenness and the shine of the binder fibers were not noticeable and were good. This dyed nonwoven fabric was processed into a futon storage bag, which had a high shielding effect and was breathable, so it had good storage stability. Effects of the Invention The thermal binder fiber of the present invention can suppress color unevenness and gloss unevenness during dyeing, provide a fiber aggregate with high concealing effect and light shielding effect, and have a different color in the core and sheath. When these pigments are blended, it becomes a color with a wide range of color changes. Above all,
It is useful as a thermal binder fiber for fiber aggregates for colored articles.

Claims (3)

[Claims] (1) In a thermal binder fiber having a pigment-containing core-sheath type composite structure, the core component is a thermoplastic polymer having a melting point of 150° C. or higher, and the sheath component is a thermoplastic polymer having a melting point at least 30° C. lower than the melting point of the core component, The pigment is contained in the sheath component of the thermal binder fiber at 0 to 5% by weight, the core component contains 0 to 5% by weight, and the total pigment content in the thermal binder fiber is 0.5 to 10% by weight. A thermal binder fiber characterized by: (2) Claim (1) wherein the cross-sectional form of the core component is an irregular cross-section.
Thermal binder fibers described in . (3) The thermal binder fiber according to claim (1) or claim (2), wherein the pigment is titanium dioxide.