JP2009072257A - Carpet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carpet which uses a polytrimethylene terephthalate which causes minimal environmental impact, has good elastic recoverability and bulkiness and good uniformity. <P>SOLUTION: The carpet includes a sheath component made of a polytrimethylene terephthalate whose fraction is 60 to 80% by mass, and a core component made of polyester other than the polytrimethylene terephthalate whose fraction is 20 to 40% by mass, and contains crimped yarns crimped by 5 to 35% containing a core-sheath conjugated fiber whose degree of cross-sectional modification is 3.0 or lower. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a carpet.

  In recent years, there has been concern about global warming caused by mass consumption of petroleum resources and depletion of petroleum resources associated with mass consumption, and environmental awareness is increasing on a global scale. In such a background, a carpet made of a material having a low environmental load is demanded.

Among materials having a low environmental load, polytrimethylene terephthalate (PTT) is attracting attention because of its excellent elastic recovery rate and bulkiness. For example, Patent Document 1 discloses a carpet using PTT. However, according to this technique, it has been difficult to produce a carpet having uniformity due to occurrence of yarn unevenness in the pile yarn. On the other hand, as a method of suppressing delayed recovery of PTT, it is disclosed to use a core-sheath composite fiber (Patent Document 2). However, when the core-sheath composite fiber yarn is applied to a carpet, there is a problem that the carpet has no volume feeling (bulky property).
JP 2000-328393 A JP 2005-281891 A

  An object of the present invention is to provide a carpet which uses polytrimethylene terephthalate which has a low environmental load and is excellent in elasticity recovery and bulkiness, and which is excellent in uniformity.

  That is, the present invention comprises a sheath component composed of polytrimethylene terephthalate having a fraction of 60 to 80% by mass and a core component composed of polyester other than polymethylene terephthalate and having a fraction of 20 to 40% by mass. A carpet characterized by comprising a crimped yarn having a crimp rate of 5 to 35% and comprising a core-sheath composite fiber of 0.0 or less.

  According to the present invention, it is possible to provide a carpet that uses polytrimethylene terephthalate with low environmental load and excellent elasticity recovery and bulkiness and excellent uniformity.

  The carpet of the present invention needs to contain polytrimethylene terephthalate (PTT) as a sheath component of the core-sheath composite fiber in the crimped yarn. By doing so, it is possible to obtain a carpet with low environmental load and excellent elasticity recovery and bulkiness. PTT is also suitable as a sheath component because it is excellent in wear resistance and moist heat aging resistance.

  PTT is a polyester containing a repeating unit composed of a 1,3-trimethylene glycol component and a terephthalic acid component (trimethylene terephthalate unit). By having a methylene chain having 3 carbon atoms in the glycol component, It has a feature that the crystal structure itself expands and contracts with respect to elongation deformation. Therefore, even when compared with polyethylene terephthalate (PET) or polybutylene terephthalate (PBT), the modulus is extremely low and the elastic recoverability is high. In contrast to PET, durability (strength retention) by wet heat treatment or alkali treatment is 2 to 4 times, which is suitable as a sheath component of the core-sheath composite fiber.

  The 1,3-trimethylene glycol constituting the trimethylene terephthalate unit is preferably derived from a biomass material from the viewpoint of low environmental load.

  In addition to the trimethylene terephthalate unit, PTT may be copolymerized with other components. However, in order to take advantage of the characteristics of PTT, the trimethylene terephthalate unit is preferably 90 mol% or more, more preferably 92 The mol% or more, more preferably 95 mol% or more.

Examples of the components that are copolymerized with PTT include diphthalic acid components such as isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 4,4 ′. Aromatic dicarboxylic acid components such as diphenyldicarboxylic acid, 4,4′diphenyletherdicarboxylic acid, 4,4′diphenylsulfonedicarboxylic acid, 5-sodiumsulfoisophthalic acid, succinic acid, adipic acid, suberic acid, sebacic acid, dodecanedione Aliphatic dicarboxylic acid components such as acid, dimer acid, and eicosandioic acid can be used.
Examples of the glycol component include ethylene glycol, 1,2-trimethylene glycol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, 2,2′bis (4′-β-hydroxyethoxyphenyl) Propane or the like can be used.
These copolymer components may be used individually by 1 type, and may use 2 or more types together.

  Moreover, the sheath component of the core-sheath composite fiber may contain additives such as other polymers, particles, flame retardants, antistatic agents, antioxidants, and ultraviolet absorbers depending on the purpose.

  The content of PTT in the sheath component of the core-sheath composite fiber is preferably 80% by mass or more, more preferably 85% by mass or more, and further preferably 90% by mass or more.

  In addition, a dimer in which two trimethylene terephthalates are linked in a cyclic manner (hereinafter referred to as “cyclic dimer”) may exist in the PTT, but the content of the cyclic dimer in the PTT is 3% by mass. The following is preferable, More preferably, it is 2.5 mass% or less, More preferably, it is 2 mass% or less. By suppressing the content of the cyclic dimer in the PTT to 3% by mass or less, the hydrolysis resistance of the PTT can be improved. Regarding the relationship between the cyclic dimer and the hydrolyzability, it is assumed that the cyclic dimer becomes a trimethylene terephthalate monomer by hydrolysis, and the hydrolysis is promoted by the catalytic action of the monomer.

  The intrinsic viscosity of PTT is preferably 0.8 to 2 dl / g, more preferably 1 to 1.8 dl / g, and still more preferably 1.2 to 1.6 dl / g. By setting it as 0.8 dl / g or more, the molecular orientation of PTT improves, the elastic recovery property of a crimped yarn, and the fastness of elastic recovery improve. On the other hand, by setting it to 2 dl / g or less, it is possible to suppress an abrupt decrease in molecular weight during melt spinning and to suppress instability of composite spinning due to instability of polymer melt flow.

  The carpet of the present invention needs to contain polyester other than PTT as the core component of the core-sheath composite fiber in the crimped yarn. By doing so, delayed recovery of the crimped yarn containing PTT can be suppressed, and a carpet having excellent uniformity can be obtained.

Polyester is composed of a dicarboxylic acid component and a glycol component.
Examples of the dicarboxylic acid component of polyester other than PTT used for the core component include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 4 , 4′diphenyldicarboxylic acid, 4,4′diphenyletherdicarboxylic acid, 4,4′diphenylsulfonedicarboxylic acid, aromatic dicarboxylic acid components such as 5-sodiumsulfoisophthalic acid, succinic acid, adipic acid, suberic acid, sebacic acid , Aliphatic dicarboxylic acid components such as dodecanedioic acid, dimer acid, and eicosandioic acid can be used. These dicarboxylic acid components may be used alone or in combination of two or more.
Examples of the glycol component include ethylene glycol, 1,3-trimethylene glycol, 1,2-trimethylene glycol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentane. Diol, 1,6-hexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, 2,2′bis (4 '-Β-hydroxyethoxyphenyl) propane or the like can be used. These glycol components may be used individually by 1 type, and may use 2 or more types together.
However, the higher the crystallinity and the higher the dimensional stability, the easier the delay recovery is suppressed, so 90 mol% or more of the polyester other than the core component PTT contains one type of dicarboxylic acid component and one type of glycol component. It is preferable that it is comprised by the repeating unit which consists of these, It is more preferable that it is 92 mol% or more, It is further more preferable that it is 95 mol% or more.

  As specific examples of polyesters other than PTT used for the core component, PET or polylactic acid is preferable for suppressing the delayed recovery of the crimped yarn and obtaining a carpet having excellent uniformity.

  As PET used for the core component, it is also preferred that other components are copolymerized in addition to the ethylene terephthalate unit. The melting point of PET consisting only of ethylene terephthalate units is 254 ° C., which is higher than the melting point of PTT (230 ° C.). In order to achieve stable composite spinning and composite fiber formation with PTT, PET in the melting temperature region of PTT This is to improve fluidity. Examples of the copolymer component include isophthalic acid and bisphenol A. The amount of copolymerization is preferably 0.1 mol% or more in order to improve the fluidity of PET. On the other hand, in order to suppress delayed recovery of PTT, it is preferably 10 mol% or less.

  The intrinsic viscosity of PET is preferably 0.4 to 0.6 dl / g, more preferably 0.43 to 0.56 dl / g, and still more preferably 0.46 to 0.53 dl / g. By setting it to 0.6 dl / g or less, stable composite spinning and composite fiber formation with PTT can be achieved. On the other hand, by setting it to 0.4 dl / g or more, heat resistance, strength, hydrolysis resistance and the like can be maintained.

Polylactic acid is a polymer having-(O-CHCH ₃ -CO) _n -as a repeating unit, and is obtained by polymerizing lactic acid and its oligomer. Lactic acid has two types of optical isomers, D-lactic acid and L-lactic acid. In any case, the higher the optical purity of polylactic acid, the higher the crystallinity of polylactic acid and the higher the melting point, that is, the heat resistance. This is preferable because the delayed recovery of the crimped yarn containing PTT can be suppressed. The optical purity of polylactic acid is preferably 90% or more, more preferably 93% or more, still more preferably 97% or more, and further preferably 99.5% or more. The melting point of polylactic acid is preferably 150 ° C. or higher in order to maintain the heat resistance of the fiber, but the melting point is about 150 ° C. with an optical purity of 90%, the melting point is about 160 ° C. with an optical purity of 93%, and the optical purity. The melting point can be about 170 ° C. at 97%.

  Also, after blending poly (L lactic acid) and poly (D lactic acid) to form a fiber core component, a high temperature heat treatment at 140 ° C. or higher is applied to form a stereocomplex, and the crystallinity is increased. The melting point can be increased to 220 to 230 ° C., which is preferable. In this case, the blend ratio of poly (L lactic acid) and poly (D lactic acid) is preferably 40/60 to 60/40 because the ratio of stereocomplex crystals can be increased.

  The polylactic acid may be copolymerized with components other than lactic acid. The components to be copolymerized include polyalkylene ether glycols such as polyethylene glycol, aliphatic polyesters such as polybutylene succinate and polyglycolic acid, aromatic polyesters such as polyethylene isophthalate, and hydroxycarboxylic acids, lactones, dicarboxylic acids, and diols. An ester bond-forming monomer such as Among these, polyalkylene ether glycol is preferable because it can control the fluidity in the melting temperature region. The amount of copolymerization is preferably 0.1 mol% or more in order to improve the fluidity of PET. On the other hand, in order to suppress delayed recovery of PTT, it is preferably 10 mol% or less.

  In addition, low molecular weight residues such as lactide may usually be present in polylactic acid, but the amount of low molecular weight residues in polylactic acid is preferably 1% by mass or less, more preferably 0.5% by mass or less. More preferably, it is 0.2% by mass or less. By suppressing the amount of low molecular weight residues in polylactic acid, hydrolysis can be suppressed and durability can be improved. Examples of a method for reducing the amount of low molecular weight residue in polylactic acid include adopting solid phase polymerization as a polymerization method and washing the pellet with warm water of about 80 ° C.

  The weight average molecular weight of polylactic acid is preferably 100,000 to 270,000, more preferably 120,000 to 260,000, still more preferably 140,000 to 250,000, and still more preferably 16 from the viewpoint of stable composite spinning with PTT. 10,000 to 240,000.

  Polylactic acid may contain modifiers such as particles, crystal nucleating agents, flame retardants, plasticizers, antistatic agents, antioxidants, ultraviolet absorbers, and crosslinking agents.

  The fraction of the sheath component made of PTT in the core-sheath composite fiber is important to be 60% by mass or more, preferably 62% by mass or more, and more preferably 65% by mass or more. By setting the content to 60% by mass or more, the PTT characteristics such as low modulus property, elastic recovery property, high bulkiness property, and hydrolysis resistance can be expressed in the core-sheath composite fiber. Moreover, the composite structure of the sheath component consisting of PTT and the core component consisting of polyester other than PTT can be stably formed.

On the other hand, the fraction of the core component made of polyester other than PTT in the core-sheath composite fiber is important to be 20% by mass or more, preferably 22% by mass or more, and more preferably 25% by mass or more.
By setting the content to 20% by mass or more, delayed recovery of the crimped yarn containing PTT can be suppressed, and as a result, a carpet having excellent uniformity can be obtained.

  The core-sheath composite structure may be a single-core structure or a multi-core structure such as a 2-core or 3-core structure.

  The carboxyl terminal concentration in the core-sheath composite fiber including the residual monomer and residual oligomer is preferably 30 equivalent / ton, preferably 20 equivalent / ton or less, more preferably 10 equivalent / ton or less. By setting it to 20 equivalents / ton or less, heat resistance and hydrolysis resistance can be improved.

  As a method for suppressing the carboxyl end group concentration, it is effective to add a terminal blocking agent having a reactive group rich in reactivity with a carboxyl end group such as an active hydrogen reactive group to the component constituting the fiber. . In addition, for example, by adding a terminal blocking agent having two or more active hydrogen reactive groups in one molecule, the terminal blocking agent reacts with the carboxyl terminal group of the sheath component and the carboxyl terminal group of the core component to bind. And the adhesiveness of the core-sheath composite interface can be further improved.

  Examples of active hydrogen reactive groups include glycidyl groups, oxazoline groups, carbodiimide groups, aziridine groups, imide groups, isocyanate groups, acid anhydride groups (groups formed from maleic anhydride (maleic anhydride groups), etc.) Can be mentioned. Among the reactive groups, a glycidyl group, an oxazoline group, a carbodiimide group, and a maleic anhydride group can be preferably used, and a glycidyl group and a carbodiimide group can be particularly preferably used.

  In addition, as a specific example of the terminal blocking agent, one having two or more glycidyl units in the triazine ring is preferable because of high heat resistance. For example, triglycidyl isocyanurate (TGIC), monoallyl diglycidyl isocyanurate (MADGIC) and the like are preferably used.

  The cross-sectional shape of the core-sheath composite fiber includes a round cross section, a hollow cross section, a porous hollow cross section, a multileaf cross section such as a trilobal cross section (triangular cross section, Y cross section, T cross section, etc.) and a four lobe cross section (X cross section), a flat cross section, It is possible to adopt a W cross section or the like.

  However, the irregularity of the cross section of the core-sheath composite fiber needs to be 3.0 or less, preferably 2.5 or less. By setting the degree of irregularity to 3.0 or less, a carpet having excellent surface smoothness and low touch by soft touch can be obtained. Also, wear resistance is improved. On the other hand, in order to obtain the bulkiness, it is preferably 1.1 or more, more preferably 1.5 or more. Here, the degree of irregularity is represented by the ratio of the diameter of the circumscribed circle to the diameter of the inscribed circle in the cross section. The circumscribed circle is a circle having the smallest diameter in a circle that touches at least two points with the outline of the cross section of the single fiber and includes the cross section of the single fiber. Further, the inscribed circle is in contact with the outline of the cross section of the single fiber at at least two points, and has the largest diameter among the circles included in the cross section of the single fiber.

  The single fiber fineness of the core-sheath composite fiber is preferably 10 to 30 dtex. By setting it to 10 dtex or more, sag when using the carpet can be suppressed. Moreover, it can suppress that a texture becomes hard by setting it as 30 dtex or less.

  The crimped yarn used in the carpet of the present invention is preferably 5% or less, more preferably 4% or less in terms of CV% as the single fiber fineness unevenness of the core-sheath composite fiber. By suppressing CV% to 5% or less, a carpet having excellent leveling and soft touch can be obtained.

  The carpet of the present invention includes a crimped yarn including the core-sheath composite fiber as described above. By having crimps, bulkiness can be obtained by bending of single fibers or entanglement of single fibers.

  As the type of crimp of the crimped yarn, false twisted yarn, mechanical crimped yarn, BCF yarn or the like can be employed.

  The crimp rate of the crimped yarn needs to be 5% or more. By setting it to 5% or more, a carpet having a high bulkiness can be obtained. On the other hand, the crimp rate is preferably 35% or less, more preferably 25% or less. By setting it to 35% or less, it is possible to prevent the texture from becoming hard due to an excessively strong crimp. In addition, it is possible to obtain a carpet product that suppresses a decrease in fiber strength and is excellent in process passability and durability.

  The strength of the crimped yarn is preferably 1.0 cN / dtex or more, more preferably 1.3 cN / dtex or more. By setting it to 1.0 cN / dtex or more, a carpet having a level of strength that can be practically used can be obtained. on the other hand. A yarn strength of 4.0 cN / dtex is sufficient.

  The boiling water shrinkage of the crimped yarn is preferably 2 to 20%, more preferably 3 to 16%, and still more preferably 4 to 12%. A higher boiling water shrinkage ratio is preferable because the bulkiness is easily exhibited in the dyeing process, steam treatment, and the like.

  The crimped yarn may be a twisted yarn in which a plurality of crimped yarns are combined and twisted in terms of carpet design, texture, touch, and the like. The number of twists is preferably 50 to 250 times / m, more preferably 80 to 200 times / m. By setting it within such a range, characteristics excellent in designability after tufting, texture, touch and the like are expressed. Moreover, it is preferable to heat-set in order to maintain a form after twisting. The heat setting temperature is preferably 80 to 150 ° C. in order to improve the shape stability of the yarn after twisting.

  The crimped yarn is preferably subjected to a dyeing process. Since the core-sheath composite fiber employed in the present invention is excellent in leveling property, it is also suitable for dyeing treatment. By performing the dyeing process, the bulkiness of the crimped yarn can be sufficiently manifested in the wet heat treatment. The dyeing treatment can be performed on crimped yarns such as cheese-like and cloth-like ones with a dyeing machine such as a cheese dyeing machine or a wins dyeing machine.

  When the crimped yarn is used without being dyed, it is also preferable to make the bulkiness apparent by boiling water treatment or steam treatment.

  The carpet of the present invention may contain fibers other than the crimped yarn in the pile portion. Specific examples of the mixed fiber include single twist, various twists, mixed fiber using an intermingle machine, and the like. However, the content of the crimped yarn in the pile portion of the carpet is preferably 50% by mass or more in order to make use of the elastic recovery and the bulkiness.

  Examples of carpet processing forms include woven carpets such as Danten, Wilton, Double Face, and Axminter, embroidery carpets such as tufting and hook drag, adhesive carpets such as bonded, electrodeposition, and cords, or combinations thereof. be able to.

  As the abrasion resistance of the carpet of the present invention, it is preferable that the grade defined as described below according to the Taber method defined in JIS L 1096 is grade 3 or higher (3 to 5 grade). By setting it to 3rd class or higher, it can be used without any problem for applications in which friction is concentrated at a specific location, such as for automobile interiors.

[Measuring method]
(1) Content of cyclic dimer Measured by high performance liquid chromatography.
A sample of 300 mg was weighed and put into an Erlenmeyer flask, and hexafluoroisopropanol and chloroform were mixed uniformly with the same volume and 10 ml of the solution was added. Then, the Erlenmeyer flask was shaken at room temperature for 5 hours to dissolve the sample. Thereafter, 5 ml of chloroform was added and mixed, and further 80 ml of acetonitrile was gradually added. The mixed solution was suction filtered through a glass filter, the filtrate was put into a 200 ml volumetric flask, and acetonitrile was added to make a 200 ml solution. This solution was filtered through a disk filter having a pore size of 0.45 μm to prepare a measurement solution.
A column (“Inert Sil” ODS-3 3.0 × 250 mm manufactured by GL Sciences Inc.) was installed in high performance liquid chromatography (LC-10AD manufactured by Shimadzu Corporation), and the column temperature was kept at 45 ° C.
As a mobile phase, a mixture of 70% by volume of acetonitrile and 30% by volume of water was passed through the column at a flow rate of 0.7 ml / min, 5 μl of the measurement solution was introduced, and an absorption peak at a wavelength of 242 nm was measured. In the obtained chromatogram was determined area A _p of the peak attributable to the cyclic dimer.
Further, as a standard sample, 10.7 mg of a cyclic dimer having a purity of 95% was weighed and a constant volume in 25 ml of chloroform was used as a standard stock solution (the concentration of the cyclic dimer having a purity of 100% in the liquid was 409 μg / ml). Then, acetonitrile was added to the standard solution to prepare four types of diluted standard solutions having a cyclic dimer concentration of 100% purity corresponding to 80 μg / ml, 40 μg / ml, 20 μg / ml, and 10 μg / ml. Each diluted standard solution was subjected to HPLC measurement, and a regression equation was obtained from the relationship between the cyclic dimer concentration in the liquid and the peak area.
And determine the liquid concentration of cyclic dimer by applying the area A _p of the peak of the sample to regression was calculated the content of the cyclic dimer from the further following equation.
Cyclic dimer content (mass%) = cyclic dimer concentration in liquid (mg / l) × 0.2 (l) / 300 (mg) × 100.

(2) Intrinsic viscosity To 0.8 g of sample, 10 ml of o-chlorophenol (hereinafter abbreviated as OCP) was added and dissolved at 160 ° C. for 30 minutes, and then slowly cooled to obtain a measurement solution. About the said measurement solution, relative viscosity (eta) _r was calculated | required by following Formula using the Ostwald viscometer at 25 degreeC, and the intrinsic viscosity was computed by the following formula.
η _r = η / η ₀ = (t × d) / (t ₀ × d ₀ )
Intrinsic viscosity = 0.0242 η _r +0.2634
Where η: viscosity of the measurement solution η ₀ : OCP viscosity t: time of solution fall (seconds)
d: density of the solution (g / cm ³ )
t ₀ : OCP fall time (seconds)
d ₀ : Density of OCP (g / cm ³ ).

(3) Weight average molecular weight of polylactic acid (Mw)
A solution obtained by dissolving the sample (polylactic acid) in chloroform so that the concentration of the sample (polylactic acid) was 10 mg / 4 ml and filtering with a disk filter (“Maishori Disk” 0.5 μm manufactured by Tosoh Corporation) was used as a measurement solution. This was measured using a gel permeation chromatography apparatus (manufactured by Shimadzu Corporation). The column used was a combination of two “shodex” K805 manufactured by Showa Denko KK, the column temperature was 40 ° C., and the mobile phase was chloroform (manufactured by Wako, for HPLC), measured at a flow rate of 1 mL / min. did. RID-10A manufactured by Shimadzu Corporation was used as the differential refractometer, and the weight average molecular weight was calculated in terms of polystyrene from the obtained peak. The number of measurements was 5, and the average value was calculated.

(4) Melting point About 10 mg of the sample was weighed, and heated with a differential scanning calorimeter (DSC-7 manufactured by Perkin Elmer) at a heating rate of 16 ° C./min, and the melting point was measured with 2nd run.

(5) Concentration of carboxyl group terminal concentration A precisely weighed sample was dissolved in o-cresol (water 5%), and an appropriate amount of dichloromethane was added to this solution, followed by titration with a 0.02 N KOH methanol solution. . At this time, an oligomer such as lactide, which is a cyclic dimer of lactic acid, is hydrolyzed to generate a carboxyl group terminal, so that all of the carboxyl group terminal of the polymer, the monomer-derived carboxyl group terminal, and the oligomer-derived carboxyl group terminal are totaled. The carboxyl group terminal concentration obtained is obtained.

(6) Deformation degree A fiber was fixed with an embedding material, a section was cut out, deembedded, and then magnified with an optical microscope and photographed. After digitizing the image, using image analysis software (Mitani Corporation “WinROOF” ver5.0), the diameter D ₁ of the circumscribed circle of the cross section of the fiber and the diameter D of the inscribed circle of the cross section of the single fiber ₂ was measured. And the irregularity degree of the single fiber was calculated | required by following Formula. Of all the single fibers constituting the multifilament, 10 were selected from those having a high degree of deformity, and the average value was calculated to the first decimal place.
Modification degree _{= D} 1 _/ D 2.

(7) Weight fraction (mass ratio) of sheath component and core component
The discharge amount (g / min) of the sheath component in melt spinning and the discharge amount (g / min) of the core component are separately measured, and the discharge amount of the core component / sheath component is determined by the discharge amount of the core component and the sheath component. The mass fraction of the core component / sheath component was calculated by dividing by 100 with the sum of the discharge amount and 100 times.

In addition, as a measurement method from the fiber after spinning, from a cross-sectional photograph of the core-sheath composite fiber,
Image analysis software (Mitani Corp. "WinROOF" ver5.0) at area _{A s} of the sheath component, and measuring the area _{A c} of the core component, with a specific gravity [rho _s of the sheath component, the specific gravity [rho _c of the core component, It can be calculated by the following formula.
Fraction of core component (%) = {A _c ρ _c / (A _c ρ _c + A _s ρ _s )} × 100
Fraction of sheath component (%) = {A _s ρ _s / (A _c ρ _c + A _s ρ _s )} × 100
The density ρ is about 1.30 g / m ^{3 for} PTT, about 1.38 g / m ^{3 for} PET, and about 1.26 g / m ^{3 for} polylactic acid.

(8) Total fineness and single fiber fineness Take a 100m yarn in a skein shape with a measuring scale, measure the mass, multiply the mass by 100, obtain the total fineness (dtex), and calculate the average value of n number 3 Calculated.
Further, the single fiber fineness (dtex) was calculated by dividing the total fineness by the number of filaments.

(9) Tensile strength, tensile elongation Measured according to JIS L 1013: 1999 8.5.1.
With the sample loosely tensioned, it was attached to the grip of a tensile tester (Orientec “Tensilon” (registered trademark) UCT-100) with a grip interval of 20 cm, and the test was performed at a constant speed extension of 20 cm / min. It was. Read the elongation when the initial load is applied as looseness (mm), pull the sample further, measure the load and elongation (mm) when the sample is cut, and use the following formula to determine the tensile strength (tensile strength) and elongation The rate (tensile elongation) was calculated. The number of tests was 10, and the average value was calculated.
T _b = SD / F ₀
Here, _{T b:} tensile strength SD: Disconnection strength F _0: positive amount fineness elongation of the sample _{(%) = [(E 2} -E 1) / (L + E 1)] × 100
Here, E ₁ : Looseness (mm)
E ₂ : Elongation at the time of cutting (mm)
L: Grasp interval (mm).

(10) Strength of crimped yarn after hydrothermal treatment (hydrolysis resistance)
A sample of 100 turns of skein was put into a thermostatic and humidity chamber (LH-20-11M, manufactured by Nagano Scientific Machinery Co., Ltd.) set at a temperature of 70 ° C. and a humidity of 95% Rh, and 168 hours (7 days) ) I left it.
The skein after the constant temperature and humidity treatment was taken out, and the tensile strength of the yarn was determined in the same manner as in (9) above.

(11) Crimp elongation rate After the crimped yarn package is left in an atmosphere of room temperature 30 ± 5 ° C. and relative humidity 50 to 75% for 20 hours or more, the crimped yarn is unwound from the package, After being immersed in boiling water for 30 minutes in an unloaded state, it was dried to an equilibrium moisture content. This was cut into a length of slightly over 50 cm to prepare a sample. An initial load of 2 mg / dtex (0.0196 mN / dtex) was applied to this sample yarn, and after 30 seconds, marking was performed at a position 50 cm (L ₁ ) in length from the hanging fulcrum. Next, a constant load of 100 mg / dtex (0.98 mN / dtex) was applied to the sample, and after 30 seconds had elapsed, the length (L2) from the hanging fulcrum to the previous marking position was measured. The crimp elongation rate was determined according to the following formula.
Crimp elongation (%) = [(L ₂ −L ₁ ) / L ₂ ] × 100.

(12) Fineness CV%
For all the single fibers constituting the multifilament, the cross-sectional area _Af was measured from the cross-sectional photograph with image analysis software (Mitani Corporation “WinROOF” ver5.0), and the average value and the standard deviation were calculated. Then, a value obtained by dividing the standard deviation by the average value and multiplying by 100 is obtained up to the first decimal place, and is defined as the fineness CV%.

(13) Weight of pile yarn The base fabric before tufting and the carpet after tufting were cut into 50 cm squares, the respective masses were measured, and each was converted into a mass (unit weight) per unit area (1 m ² ). And the difference of both fabric weights was taken and it calculated as the fabric weight of a pile yarn.

(14) Carpet Abrasion JIS L 1096: 1999 8.17.3 In accordance with the Taber method, H-18 wear wheels are used, and a load of 1 kgf (9.8 N) is applied to each of the left and right wear wheels. The carpet was worn by 300 rotations over time, and the appearance change was graded according to the following criteria.
Grade 5: No change is observed.
Grade 4: A slight change is seen, but there is almost no change.
3rd grade: Change is seen but not noticeable.
Second grade: Change is intense.
First grade: The change is quite severe.

(15) Abrasion of carpet after wet heat treatment The carpet was treated in a constant temperature and humidity chamber (manufactured by Nagano Scientific Machinery Co., Ltd., model LH-20-11M) at a bath temperature of 70 ° C. and a relative humidity of 95% for 7 days. Then, a carpet dried for 24 hours in an atmosphere of 25 ° C. and a relative humidity of 65% was used as a sample. And abrasion property was measured and evaluated in the same manner as in the above (14).

(16) Carpet Quality Evaluation Carpet feel and quality were evaluated according to the following criteria.
(Double-circle): A touch feeling and the quality are very excellent.
○: Excellent touch feeling and excellent quality.
(Triangle | delta): A touch feeling is slightly inferior and a quality is a little bad.
X: A feeling of touch is bad and quality is bad.

[Examples 1-3, Comparative Examples 1-3]
(Crimped yarn)
(Sheath component)
Intrinsic viscosity is 1.5 g / dl, Tg is 48 ° C., melting point is 230 ° C., cyclic dimer content is 2.6 mass%, carboxyl group terminal concentration is 12 eq / ton, and the average secondary particle diameter is 0.4 μm. PTT containing 3% by mass was vacuum-dried at 150 ° C. for 10 hours and used as a sheath component.

(Core component)
PET having an intrinsic viscosity of 0.5 g / dl, Tg of 70 ° C., a melting point of 254 ° C., and a carboxyl group terminal concentration of 25 eq / ton was vacuum-dried at 150 ° C. for 10 hours and used as a core component.

(Composite spinning / crimping)
The sheath component and the core component are supplied to the melt spinning machine at the fractions shown in Table 1, and are combined into a single-core core-sheath structure in the die at a spinning temperature of 270 ° C. Was discharged.
The discharged fibrous polymer was cooled and solidified with a chimney wind, an oil solution was applied, and the roll rotation speed was 700 m / min and the roll temperature was 65 ° C.
Subsequently, the first stretching was performed at a roll rotation speed of 600 m / min and a roll temperature of 120 ° C. without winding up the yarn, and then the second stretching was performed at a roll rotation speed of 1800 m / min and a roll temperature of 180 ° C.
Next, the drawn yarn was continuously guided to a crimping device without winding the yarn, and crimped with 230 ° C. heating steam, jetted onto a rotary transfer device, and cooled. Next, the plug-like yarn lump was stretched by a pair of separate rolls to break up the lump. The yarn was entangled and wound into a cheese shape to obtain a crimped yarn having 54 filaments and a total fineness of 1450 dtex.

(Mixed yarn)
Two twisted S twists were applied to the crimped yarns 210 times / m, and Z twisted 210 times / m as the upper twist, and heat setting was performed at 105 ° C. to obtain a twisted yarn.

(Dyeing / reduction cleaning)
The above twisted yarn, in the state of cheese winding, contains disperse dye ("Dianix" Blue AC-E manufactured by Dystar) 0.3% owf, dispersant ("Nikkasan Salt" 7000 manufactured by Nikka Chemical Co., Ltd.) As a pH adjuster, it was immersed in a dyeing solution in a high-pressure kettle adjusted to pH 5 with acetic acid / sodium acetate at a bath ratio (mass ratio of yarn and dyeing solution) of 1:20, and dyed at 120 ° C. for 45 minutes.
Subsequently, reduction cleaning was performed at a liquid temperature of 80 ° C. for 20 minutes.

(carpet)
The twisted yarn was washed the stain-reducing as pile yarn, the PET base fabric having a basis weight of 100g / ^{m 2,} 1/10-gauge, tufted stitch 8.7 pieces / mm, pile weight per unit area 1100 g / ^{m 2} level cut products Got the carpet.

The carpets obtained in Examples 1 to 3 had a soft touch and an excellent touch feeling, were very good in quality without any flaws caused by uneven dyeing, and had good wear and hydrolysis resistance.
The carpet obtained in Comparative Example 1 had a high fineness CV%, dyeing unevenness occurred at the time of dyeing, vertical warp was generated on the carpet after tufting, and the mat had poor quality.
Since the carpet obtained in Comparative Example 2 had a low PTT fraction, the carpet was inferior in resilience and bulkiness and in touch. Further, a stable composite structure could not be obtained, and since the fineness CV% was large, dyeing unevenness occurred at the time of dyeing, and the core-sheath peeling occurred in the abrasion test, which was inferior.

[Comparative Example 3]
(Crimped yarn)
(Sheath component)
PTT similar to that used in Examples 1 to 3 was used as the sheath component.

(Core component)
PET similar to that used in Examples 1 to 3 was used as the core component.

(Composite spinning / crimping)
In the same manner as in Example 1 except that the sheath component and the core component were supplied to the melt spinning machine at the fractions shown in Table 1, and a die having a Y-shaped hole was used, the degree of deformity 3.2, the number of filaments 54. A crimped yarn having a total fineness of 1450 dtex was obtained.

(Mixed yarn)
Using the crimped yarn, a twisted yarn was obtained in the same manner as in Examples 1 to 3.

(Dyeing / reduction cleaning)
Dyeing / reduction cleaning was performed on the above-mentioned twisted yarn in the same manner as in Examples 1 to 3.

(carpet)
Carpets were obtained in the same manner as in Examples 1 to 3, using the dyed / reduced and washed twisted yarn as a pile yarn.

  The carpet obtained in Comparative Example 3 had a high degree of irregularity in the cross-section of the fibers constituting the pile yarn, so that the carpet did not have a soft touch quality and the feel was poor. Also, in the abrasion test, a phenomenon that the sheath component tears occurred and was inferior.

[Example 4]
(Crimped yarn)
(Sheath component)
PTT similar to that used in Examples 1 to 3 was used as the sheath component.

(Core component)
L-lactic acid has an optical purity of 99.5%, a weight average molecular weight of 160,000, a low molecular weight residue (lactide) content of 0.10% by mass, Tg of 58 ° C, and a melting point of 170 ° C. Polylactic acid (PLA) is vacuumed at 150 ° C for 10 hours. Dried and used as a core component.

(Composite spinning / crimping)
The sheath component and the core component were supplied to the melt spinning machine at the fractions shown in Table 2, and the number of filaments was 54 and the total fineness was 1450 dtex in the same manner as in Examples 1 to 3 except that the spinning temperature was 255 ° C. A crimped yarn was obtained.

(Mixed yarn)
Using the crimped yarn, a twisted yarn was obtained in the same manner as in Examples 1 to 3.

(Dyeing / reduction cleaning)
Dyeing / reduction cleaning was performed on the above-mentioned twisted yarn in the same manner as in Examples 1 to 3.

(carpet)
Carpets were obtained in the same manner as in Examples 1 to 3, using the dyed / reduced and washed twisted yarn as a pile yarn.

  The carpet obtained in Example 4 had good quality, no wear due to uneven dyeing, and good wear and hydrolysis resistance.

[Comparative Example 4]
(Crimped yarn)
(Sheath component)
PTT similar to that used in Examples 1 to 3 and 4 was used as the sheath component.

(Core component)
The same PLA as used in Example 4 was used as the core component.

(Composite spinning / crimping)
Crimping is carried out in the same manner as in Examples 1 to 3 and 4 except that the sheath component and the core component are supplied to the melt spinning machine at the fractions shown in Table 2 and the roll temperature in the second stretching is 130 ° C. A crimped yarn having an elongation rate of 3%, a filament number of 54, and a total fineness of 1450 dtex was obtained.

(Mixed yarn)
Using the crimped yarn, a twisted yarn was obtained in the same manner as in Examples 1 to 3 and 4.

(Dyeing / reduction cleaning)
The above-mentioned twisted yarn was dyed / reduced and washed in the same manner as in Examples 1 to 3 and 4.

(carpet)
Carpets were obtained in the same manner as in Examples 1 to 3 and 4 using the dyed / reduced washed twisted yarn as a pile yarn.

  The carpet obtained in Comparative Example 4 had a low crimp rate of the pile yarn, so the pile yarn had no bulkiness, no volume as a carpet, and poor quality. Further, since there is no bulky property, carpet covering properties are low and wear resistance is poor.

[Comparative Example 5]
(Crimped yarn)
(Sheath component)
PTT similar to that used in Examples 1 to 3 and 4 was used as the sheath component.

(Core component)
The same PLA as used in Example 4 was used as the core component.

(Composite spinning / crimping)
In the same manner as in Examples 1 to 3 and 4, except that the sheath component and the core component were supplied to the melt spinning machine at the fractions shown in Table 2, and the temperature of the heating steam in the crimping process was 250 ° C. A crimped yarn having a crimp elongation of 40%, a filament number of 54, and a total fineness of 1450 dtex was obtained.

(Mixed yarn)
Using the crimped yarn, a twisted yarn was obtained in the same manner as in Examples 1 to 3 and 4.

(Dyeing / reduction cleaning)
The above-mentioned twisted yarn was dyed / reduced and washed in the same manner as in Examples 1 to 3 and 4.

(carpet)
Carpets were obtained in the same manner as in Examples 1 to 3 and 4 using the dyed / reduced washed twisted yarn as a pile yarn.

  The carpet obtained in Comparative Example 5 had a slightly crimped elongation rate, so that the feeling of touch was slightly inferior due to a crimp that was too strong. Moreover, the tensile strength was low and the wear resistance was poor.

[Example 5]
(Crimped yarn)
(Sheath component)
PTT similar to that used in Examples 1 to 3 and 4 was used as the sheath component.

(Core component)
The same PLA as used in Example 4 was used as the core component.

(Composite spinning / crimping)
In the same manner as in Examples 1 to 3 and 4, except that the sheath component and the core component were supplied to the melt spinning machine at the fractions shown in Table 2, and a die having 60 round holes was used. 1. A crimped yarn having a filament number of 60 and a total fineness of 1450 dtex was obtained.

(Mixed yarn)
Using the crimped yarn, a twisted yarn was obtained in the same manner as in Examples 1 to 3 and 4.

(Dyeing / reduction cleaning)
The above-mentioned twisted yarn was dyed / reduced and washed in the same manner as in Examples 1 to 3 and 4.

(carpet)
The twisted yarn was cleaning a stained-reduction as a pile yarn, a PET base fabric having a basis weight of 100g / ^{m 2,} 1/10-gauge, tufted stitch 6.9 cells / mm, automotive loop of the pile basis weight of 900g / ^{m 2} Got the carpet.

  The carpet obtained in Example 5 was good in quality without abrasion due to uneven dyeing, and had good wear and hydrolysis resistance.

  The use of the carpet of the present invention is not particularly limited, such as residential use, commercial use, and automobile use, but it is particularly suitable for use in automobile interiors that require long-term durability, wear resistance, and the like.

Claims (5)

  It consists of a sheath component made of polytrimethylene terephthalate with a fraction of 60 to 80% by mass and a core component made of polyester other than polymethylene terephthalate with a fraction of 20 to 40% by mass. A carpet characterized by comprising a crimped yarn having a crimp rate of 5 to 35% and comprising a core-sheath composite fiber.   The carpet according to claim 1, wherein the polyester as the core component is polyethylene terephthalate.   The carpet according to claim 1, wherein the polyester as the core component is polylactic acid.   The carpet in any one of Claims 1-3 whose single fiber fineness of the said core-sheath composite fiber is 10-30 dtex.   The carpet according to any one of claims 1 to 4, which is used for automobile interior.