JP2008025035A - Combined filament yarn of cellulose ester - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a combined filament yarn of cellulose ester which has an excellent touch, swelling feeling and color development when made into a fabric. <P>SOLUTION: The combined filament yarn of cellulose ester comprises a highly shrinkable cellulose ester fiber (A) having a boiling water shrinkage percentage of 7-25% and a low shrinkable cellulose ester fiber (B) having a boiling water shrinkage percentage of 2-5% and satisfies formula (I) 5%≤the boiling water shrinkage percentage of the cellulose ester fiber (A)-the boiling water shrinkage percentage of the cellulose ester fiber (B)≤20%. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cellulose ester mixed yarn having an excellent texture, swellness, and color development when made into a fabric.

  Cellulose-based materials such as cellulose esters and cellulose ethers have recently attracted a great deal of attention as biomass-based materials that are most produced on the earth and as biodegradable materials in natural environments. In addition, since the cellulosic material has a low refractive index, it also has the advantage of being excellent in vivid coloring when it is made into a fiber.

  Cellulosic fibers can be obtained by a solution spinning method or a melt spinning method. However, since the obtained fibers have a low boiling water shrinkage ratio, there is a problem that a swelling feeling cannot be obtained when the fabric is made. In order to solve such a problem, a mixed yarn of cellulose triacetate fiber and polyester fiber is immersed in an alkaline aqueous solution, and the surface of the acetate in the mixed yarn is saponified to develop ultrafine crimps. A technique for imparting a new texture has been proposed (see Patent Document 1). However, in this proposal, the cellulose triacetate fiber is dry or wet spinning using a solvent, and the polyester fiber is by melt spinning. Therefore, the two spinning methods are different, and simultaneous fiber mixing during spinning is impossible. There was a problem. Furthermore, since the polyester fiber has low color developability, there is a problem in that a shaded color difference appears in the dyed fabric, causing irritation and remarkably lowering the quality.

On the other hand, there has been proposed a technique for providing a fabric excellent in swelling and same color by mixing fibers mainly composed of cellulose ester and fibers composed of polyhydroxycarboxylic acid (see Patent Document 2). However, even in this proposal, there is a difference in dyeability due to different polymers, and the same color has room for improvement. Furthermore, since the Young's modulus of the fiber made of polyhydroxycarboxylic acid is high, it was not possible to obtain a sufficiently satisfactory flexibility as a mixed yarn.
JP-A-6-316873 (page 3) JP 2004-250798 A (pages 6-7)

  The object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a cellulose ester blended yarn having a sufficient difference in boiling water shrinkage and having an excellent texture, swell feeling and color development when made into a fabric. There is to do.

  The subject of the present invention is from a highly shrinkable cellulose ester fiber (A) having a boiling water shrinkage of 7 to 25% and a low shrinkage cellulose ester fiber (B) having a boiling water shrinkage of 2 to 5%. And can be solved by a cellulose ester mixed yarn characterized by satisfying the following formula (I).

(I) 5% ≦ boiling water shrinkage of cellulose ester fiber (A) −boiling water shrinkage of cellulose ester fiber (B) ≦ 20%
Moreover, the cellulose ester fiber (A) and / or the cellulose ester fiber (B) constituting the cellulose ester fiber has a total substitution degree of 2.5 to 3.0, and the cellulose ester fiber (A) and / or the cellulose ester fiber (B It is preferable that the acyl group carbon number of at least one part of the cellulose ester which comprises) is 3-18.

  Furthermore, it can be suitably employed that the cellulose ester constituting the cellulose ester fiber (A) and / or the cellulose ester fiber (B) is at least one of cellulose acetate propionate and cellulose acetate butyrate.

  Furthermore, it can also be preferably employed that the cellulose ester fiber (A) comprises a composition comprising an amorphous polymer having a glass transition temperature of 110 ° C to 260 ° C.

  Another object of the present invention can be achieved by a fiber structure using at least the cellulose ester mixed yarn described above.

  ADVANTAGE OF THE INVENTION According to this invention, the mixed fiber excellent in the feeling of swelling and color development than the conventional mixed fiber can be obtained. Therefore, a fiber structure such as a fabric using the mixed yarn has a good swell feeling and color developability and can be suitably used particularly for clothing.

  Hereinafter, the cellulose ester mixed yarn of the present invention will be described in detail.

  The cellulose ester mixed yarn in the present invention is composed of a highly shrinkable cellulose ester fiber (A) and a low shrinkable cellulose ester fiber (B). The difference in boiling water shrinkage between the cellulose ester fibers (A) and (B) {boiling water shrinkage (A) -boiling water shrinkage (B)} is 5% or more and 20% or less. If the difference in boiling water shrinkage is 5% or more, the desired swelling feeling can be obtained. The difference in boiling water shrinkage rate is more preferably 6% or more, and further preferably 7% or more. On the other hand, if the difference in boiling water shrinkage is 20% or less, it is preferable because no shrinkage or dyeing spots occur due to excessive shrinkage. The difference in boiling water shrinkage is more preferably 15% or less, and further preferably 10% or less.

  The highly shrinkable cellulose ester fiber (A) and the low shrinkable cellulose ester fiber (B) of the present invention are mainly composed of a cellulose ester. A fiber containing cellulose ester as a main component is preferable because excellent color developability unique to cellulose ester can be obtained. The cellulose ester of the present invention is preferably a cellulose ester having at least a part of the acyl group having 3 to 18 carbon atoms. By setting at least some of the acyl group carbon atoms to 3 to 18, a more flexible fiber can be obtained. The cellulose ester composition may be the same or different between the cellulose ester fibers (A) and (B).

  Specific examples of the cellulose ester having at least a portion of the acyl group having 3 to 18 carbon atoms include cellulose acetate propionate, cellulose propionate, cellulose acetate butyrate, and cellulose butyrate. Among them, cellulose acetate propionate in which an acetyl group having 2 acyl groups and a propionyl group having 3 acyl groups are bonded to cellulose, and an acetyl group and acyl group having 2 acyl groups in cellulose A fiber made of cellulose acetate butyrate having a butyryl group having 4 carbon atoms bonded thereto is particularly preferably used in the present invention because it has moderate hygroscopicity and good mechanical properties.

When cellulose acetate propionate and / or cellulose acetate butyrate is used as the cellulose ester, the total substitution degree of cellulose ester (acetyl substitution degree + acyl substitution degree) preferably satisfies the following formula (I). That is, if the cellulose ester total substitution degree (acetyl substitution degree + acyl substitution degree) is in the range of 2.5 or more and 3.0 or less, the heat fluidity at the time of melt molding is good, thereby preventing the coloring of the fibers. This is preferable because fibers having good color tone can be obtained. The total degree of cellulose ester substitution is more preferably 2.6 or more and 2.9 or less.
(I) 2.5 ≦ acetyl substitution degree + acyl substitution degree ≦ 3.0
The degree of acetyl substitution and the degree of acyl substitution preferably satisfy the following formulas (II) and (III) in order to have a high heat softening temperature and appropriate hygroscopicity even in the case of fibers and fabrics.
(II) 1.5 ≦ acetyl substitution degree ≦ 2.5
(III) 0.5 ≦ acyl substitution degree ≦ 1.5
It is preferable that the weight average molecular weight (Mw) of the cellulose ester fiber having 3 to 18 acyl group carbon atoms is 50,000 to 250,000. A weight average molecular weight (Mw) of 50,000 or more is preferable because the strength of the cellulose ester fiber is increased. The weight average molecular weight (Mw) is more preferably 60,000 or more, and still more preferably 80,000 or more. A weight average molecular weight (Mw) of 250,000 or less is preferable because flexible fibers can be obtained. The weight average molecular weight (Mw) is more preferably 220,000 or less, still more preferably 200,000 or less. The weight average molecular weight (Mw) is a value calculated by GPC measurement, and will be described in detail in Examples.

  The cellulose ester fiber of the present invention preferably contains a plasticizer. The amount of the plasticizer is preferably in the range of 5 to 25% by weight with respect to the entire composition from the viewpoint that the resulting fiber maintains the properties as a cellulose ester. The amount of the plasticizer is more preferably 10% by weight or more, and further preferably 15% by weight or more. The amount of plasticizer is preferably 20% by weight or less.

  As the plasticizer, a polyhydric alcohol plasticizer having good compatibility with the cellulose ester is preferable, and an ester compound having a glycerin skeleton, a polyalkylene glycol, a caprolactone compound and the like are particularly preferably used.

  Specific ester compounds having a glycerol skeleton include glycerol acetate stearate, glycerol acetate palmitate, glycerol acetate laurate, glycerol acetate caprate, glycerol acetate oleate, diglycerol tetraacetate, diglycerol tetrapropionate, di Examples thereof include, but are not limited to, glycerin tetrabutyrate, diglycerin tetracaprylate, and diglycerin tetralaurate, and these can be used alone or in combination.

  Specific examples of the polyalkylene glycol include polyethylene glycol and polypropylene glycol having an average molecular weight of preferably 200 to 4000, but are not limited thereto, and these can be used alone or in combination. . As for the average molecular weight of polyalkylene glycol, 400-1000 are more preferable.

  The cellulose ester fiber of the present invention preferably contains a phosphite-based anti-coloring agent. This is because when the phosphite-based anti-coloring agent is contained, the anti-coloring effect is very remarkable, and the color tone of the resulting fiber is improved.

  Specific examples of the phosphite-based anti-coloring agent include tetrakis (2,4-di-t-butylphenyl) [1,1-biphenyl] -4,4′-diylbisphosphonite, tetrakis (2,6-di). -T-butylphenyl) [1,1-biphenyl] -4,4'-diylbisphosphonite, tetrakis (2,6-di-t-butylphenyl-4-methyl) [1,1-biphenyl] -4 , 4′-diylbisphosphonite, bis (2.6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2-tert-butyl-4-cumylphenyl) pentaerythritol diphosphite, Bis (4-t-butyl-2-cumylphenyl) pentaerythritol diphosphite, bis (2.6-di-t-butyl-4-ethylphenyl) pentaerythritol diphosphite, bis ( .4- di -t- butyl-6-methylphenyl) pentaerythritol diphosphite are preferred.

  The blending amount of the phosphite colorant is preferably in the range of 0.005 to 0.5% by weight with respect to the cellulose ester composition. By setting the blending amount to 0.005% by weight or more, the coloring of the cellulose ester fiber can be suppressed. The blending amount of the phosphite anti-coloring agent is more preferably 0.01% by weight or more, and still more preferably 0.05% by weight or more. On the other hand, when the blending amount of the phosphite-based anti-coloring agent is 0.5% by weight or less, deterioration of the cellulose ester fiber can be suppressed, and the fiber characteristics are improved. The blending amount of the phosphite anti-coloring agent is more preferably 0.3% by weight or less, and still more preferably 0.2% by weight or less.

  In addition to the components described above, the cellulose ester fiber of the present invention includes other resins containing fatty acid esters having different acyl groups, and various additives such as matting agents, deodorants, defoamers, and color adjusters. Including additives such as flame retardants, yarn friction reducers, ultraviolet absorbers, infrared absorbers, crystal nucleating agents, antioxidants, color pigments, electrostatic agents, antibacterial agents, flame retardants and lubricants It does not matter.

  The boiling water shrinkage of the cellulose ester fiber (A) of the present invention is 7 to 25%. When the boiling water shrinkage rate is 7% or more, a swelling feeling can be obtained when a blended yarn is used. The boiling water shrinkage is more preferably 8% or more, and further preferably 9% or more. On the other hand, when the boiling water shrinkage is 25% or less, the fiber structure using the mixed yarn is not cured, which is preferable. The boiling water shrinkage is more preferably 20% or less, and further preferably 15% or less.

  The method for imparting high shrinkage to the fiber is not particularly limited. For example, high shrinkage can be imparted by adding an amorphous polymer to the cellulose ester fiber. The kind of amorphous polymer for imparting high shrinkage to the fiber is not particularly limited. The amorphous polymer is preferably a cyclic olefin polymer, polysulfone, polycarbonate, or a maleimide copolymer, more preferably a maleimide copolymer.

  The glass transition point (Tg) of the amorphous polymer is preferably 110 ° C to 260 ° C. A glass transition point (Tg) of 110 ° C. or higher is preferable because high shrinkage is exhibited when fiberized. The glass transition point (Tg) is more preferably 140 ° C. or higher, and further preferably 170 ° C. or higher. On the other hand, a glass transition point (Tg) of 260 ° C. or lower is preferable because dispersibility with the cellulose ester is improved. The glass transition point (Tg) is more preferably 250 ° C. or lower, and further preferably 240 ° C. or lower.

  When adding the maleimide copolymer preferably used in the present invention, the content of the maleimide copolymer is preferably in the range of 1 to 30% by weight with respect to the cellulose ester composition. When the content of the maleimide copolymer is 1% by weight or more, the high shrinkage of the resulting fiber is remarkably exhibited. The content of the maleimide copolymer is more preferably 2% by weight or more, and further preferably 3% by weight or more. On the other hand, when the content of the maleimide copolymer is 30% or less, the spinnability is sufficient and the fiber characteristics are good. The content of the maleimide copolymer is more preferably 15% by weight or less, and still more preferably 10% by weight or less.

  The maleimide copolymer preferably used in the present invention is a copolymer containing a maleimide in the main chain, and is a copolymer of maleimides with at least one selected from styrene, acrylonitrile, methyl methacrylate, and olefin. Is preferred. The maleimide is preferably phenylmaleimide.

  The maleimide copolymerization ratio in the maleimide copolymer preferably used in the present invention is preferably 30 to 80% by weight, more preferably 30 to 50% by weight, from the viewpoint of high shrinkage.

  The melt flow rate at 260 ° C. of the maleimide copolymer preferably used in the present invention is preferably about 1 to 40 from the viewpoint of fluidity.

  Moreover, it is preferable that the glass transition point (Tg) of a maleimide-type copolymer is 110-240 degreeC. In light of dispersibility with cellulose ester, the glass transition point (Tg) is more preferably 140 ° C. or higher, and even more preferably 170 ° C. or higher. Similarly, from the viewpoint of dispersibility with cellulose ester, the glass transition point (Tg) is more preferably 230 ° C. or less, and further preferably 220 ° C. or less. The reason for the high shrinkage developed by using maleimide copolymer is not clear, but maleimide copolymer has a rigid structure because it has interaction with cellulose ester and has a rigid structure. It is presumed to be moderately dispersed therein and inhibit the formation of the fiber structure of the cellulose ester.

  As the maleimide copolymer, for example, "" Polyimilex "(registered trademark)" (Nippon Shokubai Co., Ltd.), "" DENKA IP "(registered trademark)" (electrochemical product) are known as commercially available ones. In the present invention, these can be preferably used.

  The boiling water shrinkage of the low-shrinkage cellulose ester fiber (B) of the present invention is 2 to 5%. It is difficult to make the boiling water shrinkage smaller than 2%. On the other hand, if the boiling water shrinkage is 5% or less, it does not shrink greatly during the hot water treatment, and therefore, the difference in boiling water shrinkage from the highly shrinkable cellulose fiber (A) can be increased, which is good. A feeling of swelling can be obtained. The boiling water shrinkage is more preferably 4% or less.

  The single fiber fineness of the cellulose ester fibers (A) and (B) of the present invention is preferably 0.5 to 20 dtex. If the single fiber fineness is 0.5 dtex or more, a clear and deep color developability can be obtained by dyeing. The single fiber fineness is more preferably 1 dtex or more, and further preferably 1.3 dtex or more. On the other hand, if the single fiber fineness is 20 dtex or less, flexibility can be obtained. The single fiber fineness is more preferably 15 dtex or less, and further preferably 10 dtex or less. The single fiber fineness may be the same or different between the cellulose ester fibers (A) and (B). In addition, since the total fineness and single fiber fineness of the high-shrinkage cellulose ester fiber (A) can be made larger than that of the low-shrinkage cellulose ester fiber (B), it is possible to give a more excellent swell feeling. preferable. The cellulose ester fibers (A) and (B) may be monofilaments or multifilaments as long as they have the single fiber fineness described above, and may be short fibers (staples) in addition to long fibers.

  The fiber physical properties of the cellulose ester fibers (A) and (B) of the present invention are not particularly limited, but the strength is 0.5 to 2.0 cN / from the viewpoint of process passability in higher processing. It is preferable that dtex and elongation are 8 to 50%. When the elongation is 8% or more, the occurrence of fluff and yarn breakage is reduced in higher processing steps such as weaving and knitting. The elongation is more preferably 10% or more, and further preferably 15% or more. On the other hand, if the elongation is 50% or less, the change in the size of the fabric is small. The elongation is more preferably 40% or less, and further preferably 35% or less. The strength and elongation of the fiber may be the same or different between the cellulose ester fibers (A) and (B).

  The cellulose ester fibers (A) and (B) of the present invention are not particularly limited with respect to the cross-sectional shape of the fibers, and may be a perfect circular circular cross-section, and may be multilobal, flat, elliptical, Different cross-section yarns such as a W shape, an S shape, an X shape, an H shape, a C shape, a paddle shape, a cross girder shape, and a hollow shape may be used. The cross-sectional shape of the fiber may be the same or different between the cellulose ester fibers (A) and (B).

  Next, the cellulose ester mixed yarn of the present invention will be described.

  The ratio of the high-shrinkage cellulose ester fiber (A) and the low-shrinkage cellulose ester fiber (B) in the mixed yarn can be arbitrarily determined. For example, if the ratio of the high-shrinkage cellulose ester fiber (A) and the low-shrinkage cellulose ester fiber (B) is 2:98 to 20:80, the mixed yarn having a high flexibility is slightly inferior in feeling of swelling. can get. On the contrary, if it is 80: 20-98: 2, the mixed fiber yarn which was excellent in the feeling of swell although the softness | flexibility is low will be obtained. In the range of 20:80 to 80:20, a mixed fiber having a good balance between flexibility and bulge is obtained.

  The cellulose ester mixed yarn of the present invention preferably has a Young's modulus of 15 to 29 cN / dtex. If the Young's modulus is 15 cN / dtex or more, it has sufficient strength for making a fabric. On the other hand, if the Young's modulus is 29 cN / dtex or less, excellent swell and softness can be obtained when it is made into a fabric. The Young's modulus is more preferably 27 cN / dtex or less, and further preferably 25 cN / dtex or less.

  The physical properties of the cellulose ester mixed yarn of the present invention are not particularly limited, but the strength is 0.5 to 2.0 cN / dtex and the elongation is 8 from the viewpoint of process passability in higher processing. It is preferably ˜40%. If the elongation of the blended yarn is 8% or more, the occurrence of fluff and yarn breakage is reduced in higher processing steps such as weaving and knitting. The elongation of the mixed yarn is more preferably 9% or more, and further preferably 10% or more. On the other hand, if the elongation is 40% or less, the change in the size of the fabric is small. The elongation of the blended yarn is more preferably 35% or less, and further preferably 30% or less.

  The total fineness of the cellulose ester mixed yarn of the present invention is preferably 50 to 400 dtex. When the total fineness is 50 dtex or more, a feeling of bulge is developed. The total fineness is preferably 70 dtex or more, more preferably 100 dtex or more. On the other hand, if the total fineness is 400 dtex or less, flexibility is not impaired, which is preferable. The total fineness is preferably 350 dtex or less, more preferably 300 dtex or less.

  The cellulose ester mixed yarn of the present invention can be processed such as drawing and false twisting in the same manner as general fibers. In addition, weaving and knitting can be handled in the same way as ordinary fibers.

  The dyeing method of the cellulose ester mixed yarn of the present invention is not particularly limited, and techniques such as cheese dyeing, liquid dyeing and drum dyeing can be employed. As the dye, a disperse dye for acetate and polyester can be suitably used. The dyeing temperature is not particularly limited, but if it is 80 to 140 ° C., a fiber or fabric excellent in color development and swelling can be obtained.

  Next, the manufacturing method of the cellulose ester mixed yarn of this invention is demonstrated.

  Examples of the method for producing the cellulose ester mixed yarn of the present invention include, but are not limited to, a conventionally known post-mixing method and spinning-mixing method.

  In the cellulose ester fiber (A) of the present invention, a cellulose containing at least 70 to 99% by weight of a cellulose ester having 3 to 18 acyl group carbon atoms and 1 to 30% by weight of a maleimide copolymer as a polymer. An ester composition is preferably used. In the cellulose ester fiber (B) of the present invention, a cellulose ester composition containing at least 70 to 99% by weight of a cellulose ester having at least a part of the acyl group having 3 to 18 carbon atoms as a polymer is suitably used.

  In the cellulose ester composition, these components may be kneaded using, for example, a twin-screw kneader before melt spinning, or may be mixed using a static mixer or the like when melt spinning. Absent.

  In the present invention, it is preferable to dry the cellulose ester composition before melt spinning so that the moisture content of the composition is 0.3% by weight or less. When the moisture content is 0.3% by weight or less, it can be stably spun without foaming due to moisture during melt spinning, and the mechanical properties of the resulting multifilament and other fibers are also good. Become. The moisture content is more preferably 0.2% by weight or less, still more preferably 0.1% by weight or less, and most preferably 0.08% by weight or less.

  In the present invention, fibers can be obtained by melt spinning the cellulose ester composition. By performing melt spinning, it is possible to form a sufficiently developed fiber structure from the molten state of the cellulose ester composition to cooling and solidification. As a melt spinning method, for example, extrusion using an extruder can be employed as a suitable means.

  The spinning temperature in melt spinning is preferably in the range of 220 ° C to 280 ° C. By setting the spinning temperature to 220 ° C. or higher, the elongational viscosity of the fiber yarn discharged from the spinneret is sufficiently lowered, so that melt fracture (streamline turbulence occurs when the shear stress of the polymer is high when passing through the spinneret hole). This is a phenomenon in which periodic spots of short pitch due to occurrence and a phenomenon that the shape of the yarn discharged from the spinneret becomes irregular) do not appear, and uniform fibers can be obtained. On the other hand, since the thermal decomposition of the cellulose ester composition can be suppressed by setting the spinning temperature to 280 ° C. or less, the mechanical properties are not deteriorated due to a decrease in the molecular weight of the obtained fiber and the quality is not deteriorated due to coloring. The spinning temperature is more preferably 230 ° C to 270 ° C, and even more preferably 240 ° C to 260 ° C.

  The method for taking the spun fiber is not particularly limited, and it may be taken using a rotating roller, or may be collected by a net or the like. The spinning speed in the case of taking up using a roller is preferably 500 m / min to 3000 m / min. By setting the spinning speed to 500 m / min to 3000 m / min, it is possible to form a developed fiber structure, and fibers having excellent fiber characteristics can be obtained. The spinning speed is more preferably 1000 m / min to 2500 m / min. Moreover, after drawing a fiber, you may extend | stretch continuously and may wind up.

  As the post-mixing method, both fibers are supplied and mixed in the twisting process, both fibers are supplied and mixed in the drawing process, and both fibers are supplied and mixed in the false twisting process. A method of fiber mixing, a method of fiber mixing by air entanglement, a method of fiber mixing by Taslan processing, a method of fiber mixing by twisting or combining yarns, or by aligning, and a method of mixing by spinning by supplying two types of staples in the spinning process. Examples thereof include, but are not limited to, a method for fiber mixing, a method for fiber mixing by knit, a method for fiber mixing by knit.

  The spinning blending method includes a method of discharging yarns from two or more types of bases having different hole shapes and numbers of holes and combining and winding them at the time of winding, or a plurality of methods from a single base having a plurality of discharge holes perforated. Although the method of discharging and winding up a yarn simultaneously is mentioned, It is not limited to these.

  Further, in the case of producing a fabric such as a woven or knitted fabric or a nonwoven fabric using the mixed yarn of the present invention, the knitting / knitting machine, the woven / knitted structure, the nonwoven fabric form and the like are not particularly limited, and a known method is used. be able to.

  The cellulose ester mixed yarn of the present invention can be used as a fiber structure such as a woven fabric, a knitted fabric and a non-woven fabric, and is particularly excellent in texture, swelling feeling, and color developability. Can be suitably used.

Hereinafter, the present invention will be described in more detail with reference to examples. Each characteristic value in the examples is obtained by the following method.
A. Measurement of weight average molecular weight (Mw) by GPC It was completely dissolved in tetrahydrofuran so that the concentration of the cellulose fatty acid ester was 0.15% by weight, and used as a sample for GPC measurement. Using this sample, GPC measurement was performed with Waters 2690 under the following conditions, and the weight average molecular weight (Mw) was determined in terms of polystyrene. The number of measurements was 3, and the average value was Mw.

Column: Two Tosoh TSK gel GMHHR-H connected Detector: Waters2410 Differential refractometer RI
Moving bed solvent: Tetrahydrofuran Flow rate: 1.0 ml / min Injection volume: 200 μl
B. In an environment with high elongation, Young's modulus temperature of 20 ° C, and humidity of 65%, using a Shimadzu autograph AG-50NISMS model, a tensile test was conducted under the conditions of a sample length of 20 cm and a tensile speed of 20 cm / min. The value obtained by dividing the stress (cN) at the point indicated by the value by the fineness (dtex) was defined as the fiber strength (cN / dtex), and the elongation at break was defined as the fiber elongation (%). The initial tensile resistance was defined as the fiber Young's modulus (cN / dtex). In addition, the measurement was performed 5 times per sample, and the average value was defined as the strength, elongation, and Young's modulus of the fiber.
C. Boiling water shrinkage rate The sample was scraped and measured for sample length L0 under a load of 0.09 cN / dtex, and then treated in boiling water for 15 minutes under no load. After the treatment, the sample was air-dried, the sample length L1 was measured under a load of 0.09 cN / dtex, and calculated using the following formula. The number of measurements was 5, and the average value was defined as the boiling water shrinkage.

Boiling water shrinkage (%) = {(L0−L1) / L0} × 100
D. Dyeing characteristics A circular knitted fabric was prepared using the obtained mixed yarn, and after carrying out warm water scouring at 70 ° C. for 20 minutes, a set with dry heat at 160 ° C. for 2 minutes was performed. After that, dyeing was performed using 2% owf of Miketon FastBlueZ, which is a disperse dye, under conditions of a bath ratio of 20, a dyeing temperature of 110 ° C., and a dyeing time of 60 minutes. Regarding the levelness and sharpness of the obtained circular knitted fabric, the dyeing characteristics were evaluated by 10 visual examinations through visual sensory tests. The level dyeability was defined as a state where the entire fabric was dyed evenly and no irritation was observed. According to the sensory test, “no irritation” was evaluated as “◯”, “slight irritation” was evaluated as “△”, “with irritation” was evaluated as “x”, and “no irritation” was evaluated as “good”. On the other hand, vividness was defined as a state where a vivid and deep color was obtained with a dye. In the present invention, a blended yarn obtained by blending cellulose ester fibers is used as a reference showing extremely excellent sharpness. According to the sensory test, “excellent” was evaluated as ◎, “excellent” as ◯, “ordinary” as △, “inferior” as ×, and “excellent” as ○ or better.
E. Texture characteristics Regarding the flexibility and feeling of swelling of the circular knitted fabric after dyeing, the texture characteristics were evaluated by combining ten sensory tests with ten subjects. Evaluate flexibility and swell, `` Excellent '' is ◎, `` Excellent '' is ○, `` Normal '' is △, `` Inferior '' is ×, `` Excellent '' is more than ○ Passed.
Synthesis example 1
To 100 parts by weight of cellulose (dissolved pulp manufactured by Nippon Paper Industries Co., Ltd.), 240 parts by weight of acetic acid and 67 parts by weight of propionic acid were added and mixed at 50 ° C. for 30 minutes. After the mixture was cooled to room temperature, 172 parts by weight of acetic anhydride cooled in an ice bath and 168 parts by weight of propionic anhydride were added as an esterifying agent, and 4 parts by weight of sulfuric acid was added as an esterification catalyst, followed by stirring for 150 minutes. An esterification reaction was performed. In the esterification reaction, when it exceeded 40 ° C., it was cooled in a water bath. After the reaction, a mixed solution of 100 parts by weight of acetic acid and 33 parts by weight of water was added as a reaction terminator over 20 minutes to hydrolyze excess anhydride. Thereafter, 333 parts by weight of acetic acid and 100 parts by weight of water were added, and the mixture was heated and stirred at 80 ° C. for 1 hour. After completion of the reaction, an aqueous solution containing 6 parts by weight of sodium carbonate was added, and the precipitated cellulose acetate propionate was filtered off, subsequently washed with water, and dried at 60 ° C. for 4 hours. The cellulose acetate propionate thus obtained had an acetyl substitution degree of 2.0, a propionyl substitution degree of 0.7 (total cellulose ester substitution degree of 2.7), and a weight average molecular weight (Mw) of 178,000. It was.

Example 1
77.9% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 17.0% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, maleimide copolymer (electrochemical industry “DENKAIP MS-NA” styrene / anhydrous Maleic acid / N-phenylmaleimide = 50.1 / 1.8 / 48.1, MFR (260 ° C.) = 2.5, Tg 196 ° C.) 5.0% by weight and bis (2, 6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite 0.1% by weight using a biaxial extruder at 230 ° C., cutting to about 5 mm, and cellulose ester composition pellets (MW16 .60,000).

  This pellet was vacuum dried at 80 ° C. for 8 hours, and spun from a die having 12 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 10.0 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min Winding with a winder to obtain yarn A. The properties of the obtained fiber are shown in Table 1.

  82% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 17.9% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, and bis (2,6-di-t-butyl-4 as a phosphite colorant -Methylphenyl) pentaerythritol diphosphite 0.1% by weight was kneaded at 230 ° C. using a biaxial extruder and cut to about 5 mm to obtain cellulose ester composition pellets (MW 16,000,000).

  This pellet was vacuum dried at 80 ° C. for 8 hours, and spun from a die having 12 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 10.0 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min A yarn B was obtained by winding with a winder via a second godet roller rotating at 1000 m / min. The properties of the obtained fiber are shown in Table 1.

  Yarn A and Yarn B were mixed by air entanglement at a mixing ratio of 50:50 to form a uniform mixed yarn, and then knitted using a circular knitting machine. This knitted fabric was scoured, set and dyed by the method described above. The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 1, and had extremely excellent dyeability and texture.

Example 2
In the yarn A of Example 1, the maleimide copolymer was designated as “DENKAIP MS-L2A” (styrene / maleic anhydride / N-phenylmaleimide = 49.7 / 6.2 / 44.1, MFR (260 ° C.)). = 2.5, Tg 196 ° C.) Threads A and B and mixed yarn were produced in the same manner. The weight average molecular weight (MW) of the cellulose ester composition used for the production of the yarn A was 162,000. The properties of the obtained fiber are shown in Table 1.

  The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 1, and had extremely excellent dyeability and texture.

Example 3
In Example 2, the yarns A and B and the mixed yarn were manufactured in the same manner except that the mixing ratio of the mixed yarn was changed to A: B = 80: 20. The properties of the obtained fiber are shown in Table 1.

  The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 1. The dyeing characteristics and texture characteristics were extremely excellent. In addition, although the Young's modulus of the mixed yarn was somewhat low, it had excellent flexibility.

Example 4
Except for changing the discharge amount of the thread A to 7.0 g / min and the number of the nozzle holes to 6, the thread A and the thread B are the same as in Example 2 except that the number of the nozzle holes is changed to 24. Yarn B was produced in the same manner as in Example 2. The mixed yarn was produced in the same manner as in Example 2. The properties of the obtained fiber are shown in Table 1.

  The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 1, and had extremely excellent dyeability. In addition, since the boiling water shrinkage rate of the yarn B is 4.2%, the difference in boiling water shrinkage rate of the blended yarn is slightly small at 5%, which is slightly inferior to that of Example 3. A feeling of swell was felt.

Example 5
Cellulose acetate propionate (CAP482-20) manufactured by Eastman Chemical Co. having an acetyl substitution degree of 0.2 and a propionyl substitution degree of 2.5 (cellulose ester total substitution degree of 2.7), 86.9% by weight, average molecular weight 600 wt% polyethylene glycol (PEG 600), maleimide copolymer (Electrochemical Industry “DENKAIP MS-L2A” styrene / maleic anhydride / N-phenylmaleimide = 49.7 / 6.2 / 44.1) , MFR (260 ° C.) = 2.5, Tg 196 ° C.) 5.0% by weight and bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite 0 as a phosphite colorant 1% by weight is kneaded at 230 ° C using a biaxial extruder and cut to about 5mm Suesuteru composition to obtain a pellet (MW16.1 50,000).

  This pellet was vacuum-dried at 80 ° C. for 8 hours, and spun from a die having 12 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 8.4 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min The yarn A was obtained by winding with a winder via a second godet roller rotating at 1000 m / min. The properties of the obtained fiber are shown in Table 1.

  82% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 17.9% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, and bis (2,6-di-t-butyl-4 as a phosphite colorant -Methylphenyl) pentaerythritol diphosphite 0.1% by weight was kneaded at 230 ° C. using a biaxial extruder and cut to about 5 mm to obtain cellulose ester composition pellets (MW 16,000,000).

  This pellet was vacuum dried at 80 ° C. for 8 hours, and spun from a die having 6 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 10.0 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min Winding with a winder, yarn B was obtained. The properties of the obtained fiber are shown in Table 1.

  Yarn A and Yarn B were mixed by air entanglement at a mixing ratio of 40:60 to form a uniform mixed yarn, and then knitted using a circular knitting machine. This knitted fabric was scoured, set and dyed by the method described above. The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 1, and had extremely excellent dyeability. In addition, although the Young's modulus of the blended yarn was slightly low, it had excellent flexibility, and had an excellent feeling of swelling even though the difference in boiling water shrinkage of the blended yarn was slightly small. .

Example 6
73.9% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 16.0% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, maleimide copolymer (electrochemical industry “DENKAIP MS-L2A” styrene / anhydrous Maleic acid / N-phenylmaleimide = 49.7 / 6.2 / 44.1, MFR (260 ° C.) = 2.5, Tg 196 ° C.) 10.0% by weight and bis (2, 6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite 0.1% by weight using a biaxial extruder at 230 ° C., cutting to about 5 mm, and cellulose ester composition pellets (MW16 .30,000).

  The pellets were vacuum dried at 80 ° C. for 8 hours, and spun from a die having 72 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. and a discharge rate of 10 g / min. After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min Winding with a winder to obtain yarn A. The properties of the obtained fiber are shown in Table 1.

  82% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 17.9% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, and bis (2,6-di-t-butyl-4 as a phosphite colorant -Methylphenyl) pentaerythritol diphosphite 0.1% by weight was kneaded at 230 ° C. using a biaxial extruder and cut to about 5 mm to obtain cellulose ester composition pellets (MW 16,000,000).

  This pellet was vacuum dried at 80 ° C. for 8 hours, and spun from a die having 12 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 10.0 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min Winding with a winder, yarn B was obtained. The properties of the obtained fiber are shown in Table 1.

  Yarn A and Yarn B were mixed by air entanglement at a mixing ratio of 70:30 to form a uniform mixed yarn, and then knitted using a circular knitting machine. This knitted fabric was scoured, set and dyed by the method described above. The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 1, and had extremely excellent dyeability and texture.

Example 7
In Example 1, the yarn A and the mixed yarn were produced in the same manner except that an acetate fiber (100 dtex-24fila) having an acetyl substitution degree of 2.6 was used as the yarn B. The properties of the obtained fiber are shown in Table 2.

  The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 2, and the dyeability and the feeling of swelling were extremely excellent. Moreover, despite the slightly higher Young's modulus of the blended yarn, it had excellent flexibility.

Example 8
Cellulose acetate butyrate (CAB171-15) manufactured by Eastman Chemical Co. having an acetyl substitution degree of 2.0 and a butyryl substitution degree of 0.7 (cellulose ester total substitution degree of 2.7), an average molecular weight of 600 Polyethylene glycol (PEG600) 14.0% by weight, maleimide copolymer (Electrochemical Industry “DENKAIP MS-NA” styrene / maleic anhydride / N-phenylmaleimide = 50.1 / 1.8 / 48.1, MFR (260 ° C.) = 2.5, Tg 196 ° C.) 5.0% by weight and bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite as a phosphite colorant 1% by weight is kneaded at 230 ° C. using a biaxial extruder and cut to about 5 mm to obtain a cellulose ester. It was obtained ether composition pellets (MW15.8 ten thousand).

  This pellet was vacuum-dried at 80 ° C. for 8 hours, and spun from a die having 12 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 8.4 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min The yarn A was obtained by winding with a winder via a second godet roller rotating at 1000 m / min. The properties of the obtained fiber are shown in Table 2.

  82% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 17.9% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, and bis (2,6-di-t-butyl-4 as a phosphite colorant -Methylphenyl) pentaerythritol diphosphite 0.1% by weight was kneaded at 230 ° C. using a biaxial extruder and cut to about 5 mm to obtain cellulose ester composition pellets (MW 16,000,000).

  This pellet was vacuum dried at 80 ° C. for 8 hours, and spun from a die having 12 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 10.0 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min A yarn B was obtained by winding with a winder via a second godet roller rotating at 1000 m / min. The properties of the obtained fiber are shown in Table 2.

  Yarn A and Yarn B were mixed by air entanglement at a mixing ratio of 50:50 to form a uniform mixed yarn, and then knitted using a circular knitting machine. This knitted fabric was scoured, set and dyed by the method described above. The dyeing characteristics and texture characteristics of the resulting knitted fabric are as shown in Table 2, and had extremely excellent dyeability and flexibility. Moreover, although the boiling water shrinkage | contraction rate difference of the mixed yarn was a little small, it had the outstanding swell feeling.

Example 9
Cellulose acetate butyrate manufactured by Eastman Chemical Co., Ltd., having a acetyl substitution degree of 2.0 and a butyryl substitution degree of 0.7 (cellulose ester total substitution degree of 2.7) in the yarn A of Example 8 (CAB381-20) Yarns A and B and mixed yarn were produced in the same manner except that 89.9 wt% and polyethylene glycol (PEG600) were changed to 5.0 wt%. The weight average molecular weight (MW) of the cellulose ester composition used for the production of the yarn A was 15.9 million. The properties of the obtained fiber are shown in Table 2.

  The dyeing characteristics and texture characteristics of the resulting knitted fabric are as shown in Table 2, and had extremely excellent dyeability and flexibility. Moreover, although the boiling water shrinkage | contraction rate difference of the mixed yarn was a little small, it had the outstanding swell feeling.

Example 10
82% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 17.9% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, and bis (2,6-di-t-butyl-4 as a phosphite colorant -Methylphenyl) pentaerythritol diphosphite 0.1% by weight was kneaded at 230 ° C. using a biaxial extruder, and cut to about 5 mm to obtain cellulose ester composition pellets (MW 166,000).

  This pellet was vacuum dried at 80 ° C. for 8 hours, and spun from a die having 12 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 10.0 g / min. . The spun yarn was cooled by cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applied with an oil agent, converged, and then taken up by a first godet roller rotating at 1000 m / min. Subsequently, the yarn A was obtained by winding it with a winder without heat treatment through a second godet roller (roller surface temperature 26 ° C.) rotating at 1100 m / min (stretching ratio 1.1 times). It was.

On the other hand, the obtained cellulose ester composition pellets were vacuum-dried at 80 ° C. for 8 hours, and 12 nozzle holes of 0.23 mmφ−0.30 mmL were formed at a spinning temperature of 260 ° C. under a discharge rate of 15.0 g / min. Spinning from the mouthpiece. After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging it, after taking it up with a first godet roller rotating at 1500 m / min The yarn B was obtained by winding with a winder via a second godet roller rotating at 1500 m / min. The properties of the obtained fiber are shown in Table 2.
Yarn A and Yarn B were mixed by air entanglement at a mixing ratio of 50:50 to form a uniform mixed yarn, and then knitted using a circular knitting machine. This knitted fabric was scoured, set and dyed by the method described above. The dyeing characteristics and texture characteristics of the resulting knitted fabric are as shown in Table 2, and had extremely excellent dyeability and flexibility. Moreover, although the boiling water shrinkage | contraction rate difference of the mixed yarn was a little small, it had the outstanding swell feeling.

Comparative Example 1
In Example 1, the yarn B and the mixed yarn were produced in the same manner except that polyethylene terephthalate fiber (56 dtex-24fila) was used as the yarn A. Table 3 shows the characteristics of the obtained fiber.

  Table 3 shows the dyeing characteristics and texture characteristics of the obtained knitted fabric. Due to the low color developability of the polyethylene terephthalate fiber, the levelness of the knitted fabric was extremely poor and irritations were observed. The sharpness was normal (Δ) as compared to the case of using a mixed yarn in which cellulose ester fibers were extremely excellent. In addition, since it had a sufficient difference in boiling water shrinkage rate, it had a very good feeling of swell, but due to the high Young's modulus of the mixed yarn, it was a hard fabric without flexibility .

Comparative Example 2
Polylactic acid pellets (MW 12 million) were vacuum-dried at 80 ° C. for 12 hours, and a nozzle hole of 0.23 mmφ−0.30 mmL was formed at a spinning temperature of 220 ° C. and a discharge rate of 27.0 g / min. Spinning from the mouthpiece. The spun yarn is cooled by cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, and is applied with an oil agent to be converged. Then, the spun yarn is unwound by a first godet roller rotating at 3000 m / min. A drawn yarn was obtained. Using a hot roller type drawing machine, this was drawn under the conditions of a first hot roller temperature of 90 ° C., a second hot roller temperature of 130 ° C., a draw ratio of 1.5 times, and a drawing speed of 800 m / min to obtain a yarn A. It was.

  Further, 82% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 17.9% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, and bis (2,6-di-tert-butyl as a phosphite colorant) -4-methylphenyl) pentaerythritol diphosphite 0.1% by weight was kneaded at 230 ° C. using a biaxial extruder, and cut to about 5 mm to obtain cellulose ester composition pellets (MW 16.000,000). .

  This pellet was vacuum dried at 80 ° C. for 8 hours, and spun from a die having 12 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 10.0 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min Winding with a winder, yarn B was obtained. Table 3 shows the characteristics of the obtained fiber.

  Yarn A and Yarn B were mixed by air entanglement at a mixing ratio of 50:50 to form a uniform mixed yarn, and then knitted using a circular knitting machine. This knitted fabric was scoured, set and dyed by the method described above. Table 3 shows the dyeing characteristics and texture characteristics of the obtained knitted fabric. Due to the difference in color developability between cellulose ester fiber and polylactic acid fiber, slight irritation was observed. The sharpness was slightly inferior compared with the case of using a mixed yarn obtained by mixing extremely excellent cellulose ester fibers, and was excellent (◯). In addition, although the difference in boiling shrinkage of the blended yarn was slightly small, the feeling of swelling was excellent, but due to the high Young's modulus of the blended yarn, the softness was low and the fabric was slightly hard. It was.

Comparative Example 3
82% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 17.9% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, and bis (2,6-di-t-butyl-4 as a phosphite colorant -Methylphenyl) pentaerythritol diphosphite 0.1% by weight was kneaded at 230 ° C. using a biaxial extruder, and cut to about 5 mm to obtain cellulose ester composition pellets (MW 166,000).

  This pellet was vacuum dried at 80 ° C. for 8 hours, and spun from a die having 12 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 10.0 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min Winding with a winder to obtain yarn A. Moreover, the thread B was manufactured similarly to the thread A. Table 3 shows the characteristics of the obtained fiber.

  Yarn A and Yarn B were mixed by air entanglement at a mixing ratio of 50:50 to form a uniform mixed yarn, and then knitted using a circular knitting machine. This knitted fabric was scoured, set and dyed by the method described above. The dyeing and texture characteristics of the knitted fabric obtained are as shown in Table 3 and had excellent dyeability and flexibility, but due to the fact that there was no difference in boiling water shrinkage rate, the bulge The feeling was inferior.

Comparative Example 4
Yarn A was produced in the same manner as in Example 1, and knitted using a circular knitting machine without performing fiber mixing. This knitted fabric was scoured, set and dyed by the method described above. The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 3. Although the dyeing characteristics and softness were extremely excellent, the feeling of swelling was inferior because the fibers were not mixed.

Comparative Example 5
77.9% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 17.0% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, maleimide copolymer (electrochemical industry “DENKAIP MS-L2A” styrene / anhydrous Maleic acid / N-phenylmaleimide = 49.7 / 6.2 / 44.1, MFR (260 ° C.) = 2.5, Tg 196 ° C.) 5.0% by weight and bis (2, 6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite 0.1% by weight using a biaxial extruder at 230 ° C., cutting to about 5 mm, and cellulose ester composition pellets (MW16 .40,000).

  This pellet was vacuum dried at 80 ° C. for 8 hours, and spun from a die having 6 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 7.0 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min Winding with a winder to obtain yarn A. Table 4 shows the characteristics of the obtained fiber.

  82% by weight of cellulose acetate propionate prepared in Synthesis Example 1, 17.9% by weight of polyethylene glycol (PEG 600) having an average molecular weight of 600, and bis (2,6-di-t-butyl-4 as a phosphite colorant -Methylphenyl) pentaerythritol diphosphite 0.1% by weight was kneaded at 230 ° C. using a biaxial extruder and cut to about 5 mm to obtain cellulose ester composition pellets (MW 16,000,000).

  This pellet was vacuum-dried at 80 ° C. for 8 hours, and was spun from a die having 24 holes of 0.23 mmφ−0.30 mmL at a spinning temperature of 260 ° C. under a discharge rate of 10.0 g / min. . After cooling this spun yarn with cooling air at a temperature of 25 ° C. and a wind speed of 0.25 m / sec, applying an oil agent and converging, and then picking it up with a first godet roller rotating at 1000 m / min Winding with a winder, yarn B was obtained. Table 4 shows the characteristics of the obtained fiber.

  Yarn A and Yarn B were mixed by air entanglement at a mixing ratio of 50:50 to form a uniform mixed yarn, and then knitted using a circular knitting machine. This knitted fabric was scoured, set and dyed by the method described above. The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 4 and had extremely excellent dyeability and flexibility, but did not have a sufficient difference in shrinkage of boiling water. The feeling was normal (△).

Comparative Example 6
The yarns A and B and the mixed yarn were produced in the same manner except that the discharge amount was changed to 10.0 g / min in the yarn A of Comparative Example 5 and the number of cap holes in the yarn B was changed to 12. Table 4 shows the characteristics of the obtained fiber.

  The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 4 and had extremely excellent dyeability and flexibility, but due to the low boiling water shrinkage of the yarn A. The sufficient boiling water shrinkage difference could not be obtained, and the swelled feeling was poor.

Comparative Example 7
In Example 1, yarns A and B and mixed yarn were produced in the same manner except that the maleimide copolymer was changed to a polyester elastomer (Toray DuPont "Hytrel 2571", Tg 60 ° C). The weight average molecular weight (MW) of the cellulose ester composition used for the production of the yarn A was 162,000. Table 4 shows the characteristics of the obtained fiber.

  The dyeing characteristics and texture characteristics of the obtained knitted fabric are as shown in Table 4 and had extremely excellent dyeability and flexibility, but the difference in boiling water shrinkage of the yarn A was low. Thus, a sufficient difference in boiling water shrinkage rate could not be obtained, and the feeling of swelling was inferior.

  The cellulose ester mixed yarn of the present invention has excellent texture, swelling feeling, and color developability. Therefore, a fiber structure such as a fabric using the mixed yarn has a good swell feeling and color developability and can be suitably used particularly for clothing.

Claims (5)

It consists of a highly shrinkable cellulose ester fiber (A) having a boiling water shrinkage of 7 to 25% and a low shrinkage cellulose ester fiber (B) having a boiling water shrinkage of 2 to 5%, and the following formula (I) A cellulose ester mixed yarn characterized by satisfying
(I) 5% ≦ boiling water shrinkage of cellulose ester fiber (A) −boiling water shrinkage of cellulose ester fiber (B) ≦ 20%   The total degree of substitution of the cellulose ester constituting the cellulose ester fiber (A) and / or the cellulose ester fiber (B) is 2.5 to 3.0, and the cellulose ester fiber (A) and / or the cellulose ester fiber (B) The cellulose ester mixed yarn according to claim 1, wherein the cellulose ester constituting at least part of the acyl ester has 3 to 18 carbon atoms.   The cellulose ester constituting the cellulose ester fiber (A) and / or the cellulose ester fiber (B) is at least one of cellulose acetate propionate or cellulose acetate butyrate, according to claim 1 or 2. Cellulose ester blended yarn.   The cellulose ester fiber (A) is composed of a composition comprising an amorphous polymer having a glass transition point (Tg) of 110 ° C to 260 ° C. Cellulose ester blend yarn.   A fiber structure comprising at least the cellulose ester mixed yarn according to any one of claims 1 to 4.