JP5099507B2 - Method for producing polylactic acid knitted fabric and method for producing clothing - Google Patents

Description

  The present invention relates to a polylactic acid knitted fabric containing polylactic acid fibers that is excellent in deep color without impairing the texture of the knitted fabric, and a method for producing the same.

In recent years, for the purpose of protecting the global environment, biodegradable polymers that are decomposed in a natural environment have attracted attention and are being studied all over the world. Known biodegradable polymers include polyhydroxybutyrate, polycaprolactone, aliphatic polyester, polylactic acid, and the like. Among them, polylactic acid is considered to be used not only as a biodegradable polymer but also as a versatile polymer in consideration of the global environment because lactic acid or lactide, which is a raw material of polylactic acid, can be produced from natural products. Patent Document 2). However, polylactic acid fibers are inferior in heat resistance to ordinary polyester fibers such as polyethylene terephthalate fibers, so that they are hardened during the dyeing process and the texture becomes hard, and the dyeing temperature cannot be raised, so that deep color cannot be obtained. There was a problem.
International Publication No. 2008/029934 Pamphlet

  The present invention has been made in view of the above-mentioned background, and an object thereof is to provide a polylactic acid knitted fabric containing polylactic acid fibers that is excellent in deep color without impairing the texture of the knitted fabric, a method for producing the same, and a garment. There is.

  As a result of intensive investigations to achieve the above-mentioned problems, the present inventors have spun poly L-lactic acid (A component) and poly D-component (B component) in the presence of a specific phosphate metal salt (C component). When a dyeing process is performed after forming a knitted fabric with a predetermined density using a polylactic acid filament obtained by stretching, a polylactic acid knitted fabric excellent in deep colorability can be obtained without impairing the texture of the knitted fabric The present invention has been completed by repeated headings and further intensive studies.

Thus, according to the present invention, "(i) poly L-lactic acid (A component), (ii) poly D-lactic acid (B component) and (iii) 0.05 parts per 100 parts by weight of the total of A component and B component" ~ 5 parts by weight of a polylactic acid composition containing a phosphoric acid ester metal salt (component C) represented by the following formula (1) or (2) is melt-spun to obtain an undrawn yarn; the process and the drawn yarn obtained drawn yarn at 140 ° C. and facilities the dyeing polylactic acid knitted fabric comprising a polylactic acid filament obtained by heat treating at 170 to 220 ° C., and the knitted fabric after dyeing, 1 square 2 A method for producing a dyed polylactic acid knitted fabric characterized in that the number of loops per 54 cm is in the range of 200 to 10,000 ”is provided.

式中、Ｒ_１は水素原子または炭素数１〜４のアルキル基を表し、Ｒ_２、Ｒ_３は各々独立に水素原子または炭素数１〜１２のアルキル基を表し、Ｍ_１はアルカリ金属原子またはアルカリ土類金属原子を表し、ｐは１または２を表す。

In the formula, R ₁ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ₂ and R ₃ each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and M ₁ represents an alkali metal atom or Represents an alkaline earth metal atom, and p represents 1 or 2.

式中、Ｒ_４、Ｒ_５およびＲ_６は、各々独立に水素原子または炭素数１〜１２のアルキル基を表し、Ｍ_２はアルカリ金属原子またはアルカリ土類金属原子を表し、ｐは１または２を表す。

In the formula, each of R ₄ , R ₅ and R ₆ independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, M ₂ represents an alkali metal atom or an alkaline earth metal atom, and p represents 1 or 2 Represents.

At that time, the polylactic acid composition contains 0.1 to 5 parts by weight of a carboxyl terminal blocking agent per 100 parts by weight in total of the poly L-lactic acid component (component A) and the poly D-lactic acid component (component B). It is preferable to contain. Moreover, it is preferable that the single yarn fineness of the said polylactic acid filament exists in the range of 0.1-6.0 dtex. Moreover, it is preferable that the knitted fabric is composed only of the polylactic acid filament. The L value of the knitted fabric after dyeing is preferably 15 or less.

Moreover, according to the present invention, there is provided a method for producing a dyed and processed polylactic acid knitted fabric as described above, wherein the dyeing temperature is in the range of 100 to 140 ° C. Is done.
Further, according to the present invention, to obtain a garment using a polylactic acid knitted fabric obtained by the manufacturing method described in the method for producing a garment is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the polylactic acid knitted fabric containing the polylactic acid fiber excellent in deep color property without impairing the texture of a knitted fabric, its manufacturing method, and clothing are obtained.

Hereinafter, the present invention will be described in detail.
The poly L-lactic acid (component A) used in the present invention mainly comprises L-lactic acid units. The L-lactic acid unit is a repeating unit derived from L-lactic acid. The poly L-lactic acid (component A) preferably contains 90 to 100 mol%, more preferably 95 to 100 mol%, and still more preferably 98 to 100 mol% of L-lactic acid units. Other repeating units include D-lactic acid units and units other than lactic acid. The D-lactic acid unit and the units other than lactic acid are preferably 0 to 10 mol%, more preferably 0 to 5 mol%, still more preferably 0 to 2 mol%.

  Examples of units other than lactic acid include hydroxycarboxylic acids such as glycolic acid, caprolactone, butyrolactone, propiolactone, ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,4-propanediol, 1,5 -Propanediol, hexanediol, octanediol, decanediol, dodecanediol, aliphatic diols having 2 to 30 carbon atoms, succinic acid, maleic acid, adipic acid, aliphatic dicarboxylic acids having 2 to 30 carbon atoms, terephthalic acid And units derived from one or more monomers selected from aromatic diols such as isophthalic acid, hydroxybenzoic acid, and hydroquinone, and aromatic dicarboxylic acids.

The poly L-lactic acid (component A) preferably has crystallinity. The melting point is preferably 150 to 190 ° C, more preferably 160 to 190 ° C. If these conditions are satisfied, a stereocomplex crystal having a high melting point can be formed and the crystallinity can be increased.
In poly L-lactic acid (component A), the weight average molecular weight is preferably 50,000 to 300,000 (more preferably 100,000 to 250,000).

  On the other hand, poly D-lactic acid (B component) used in the present invention mainly comprises D-lactic acid units. The D-lactic acid unit is a repeating unit derived from D-lactic acid. The poly-D-lactic acid preferably contains 90 to 100 mol%, more preferably 95 to 100 mol%, and still more preferably 98 to 100 mol% of D-lactic acid units. Other repeating units include L-lactic acid units and units other than lactic acid. The L-lactic acid unit and the units other than lactic acid are preferably 0 to 10 mol%, more preferably 0 to 5 mol%, still more preferably 0 to 2 mol%.

  Examples of units other than lactic acid include hydroxycarboxylic acids such as glycolic acid, caprolactone, butyrolactone, propiolactone, ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,4-propanediol, 1,5 -Propanediol, hexanediol, octanediol, decanediol, dodecanediol, aliphatic diols having 2 to 30 carbon atoms, succinic acid, maleic acid, adipic acid, aliphatic dicarboxylic acids having 2 to 30 carbon atoms, terephthalic acid And units derived from one or more monomers selected from aromatic diols such as isophthalic acid, hydroxybenzoic acid, and hydroquinone, and aromatic dicarboxylic acids.

Poly D-lactic acid (component B) preferably has crystallinity. The melting point is preferably 150 to 190 ° C, more preferably 160 to 190 ° C. If these conditions are satisfied, a stereocomplex crystal having a high melting point can be formed and the crystallinity can be increased.
In poly D-lactic acid (component B), the weight average molecular weight is preferably 50,000 to 300,000 (more preferably 100,000 to 250,000).

  Poly-L-lactic acid (component A) or poly-D-lactic acid (component B) can be produced by directly dehydrating condensation of L-lactic acid or D-lactic acid, or once dehydrating and cyclizing L-lactic acid or D-lactic acid. It can be produced by a method of ring-opening polymerization after making lactide. Catalysts used in these methods include divalent tin compounds such as tin octylate, tin chloride, and tin alkoxides, tetravalent tin compounds such as tin oxide, butyltin oxide, and ethyltin oxide, metal tin, zinc compounds, aluminum compounds, Examples thereof include calcium compounds and lanthanide compounds.

  The poly L-lactic acid (component A) and the poly D-lactic acid (component B) are preferably washed away with a polymerization catalyst used during the polymerization, or the catalytic activity is deactivated. A catalyst deactivator can be used to inactivate the catalyst activity.

As a catalyst deactivator, an organic ligand consisting of a group of chelate ligands having an imino group and capable of coordinating to a metal polymerization catalyst, a phosphorus oxoacid, a phosphorus oxoacid ester, and an organic phosphorus oxoacid compound represented by the formula (3) There may be mentioned at least one selected from the group. The catalyst deactivator is preferably blended in an amount of 0.3 to 20 equivalents, more preferably 0.4 to 15 equivalents, and even more preferably 0.5 to 10 equivalents per equivalent of the metal element in the catalyst at the end of the polymerization. .
_{X 1 -P (= O) m} (OH) n (OX 2) 2-n (3)
In the formula, m is 0 or 1, n is 1 or 2, and X ₁ and X ₂ each independently represent a hydrocarbon group optionally having a substituent having 1 to 20 carbon atoms. Examples of the hydrocarbon group include alkyl groups having 1 to 20 carbon atoms such as a methyl group, an ethyl group, a propyl group, and a butyl group.

  The metal ion content in poly L-lactic acid (component A) and poly D-lactic acid (component B) is preferably 20 ppm or less from the viewpoint of heat resistance and hydrolysis resistance of the fiber. The metal ion content is preferably such that the content of each metal selected from alkaline earth metals, rare earths, transition metals of the third period, aluminum, germanium, tin and antimony is 20 ppm or less.

  Next, the phosphoric acid ester metal salt (component C) used in the present invention is a compound represented by the following formula (1) or (2). The phosphoric acid ester metal salt may be used alone or in combination.

In Formula (1), R ₁ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms represented by R ₁ include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, and an iso-butyl group. The
R ₂ and R ₃ each independently represent a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. Examples of the alkyl group having 1 to 12 carbon atoms include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, sec-butyl group, iso-butyl group, tert-butyl group, amyl group, tert-amyl group, hexyl group, heptyl group, octyl group, iso-octyl group, tert-octyl group, 2-ethylhexyl group, nonyl group, iso-nonyl group, decyl group, iso-decyl group, tert-decyl group, An undecyl group, a dodecyl group, a tert-dodecyl group, etc. are mentioned.
M ₁ represents an alkali metal atom such as Na, K or Li or an alkaline earth metal atom such as Mg or Ca. p represents 1 or 2.

Preferable examples of the phosphoric acid ester metal salt represented by the formula (1) include those in which R ₁ is a hydrogen atom and R ₂ and R ₃ are both tert-butyl groups.

In the formula (2), R ₄ , R ₅ and R ₆ each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. Examples of the alkyl group having 1 to 12 carbon atoms include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, sec-butyl group, iso-butyl group, tert-butyl group, amyl group, tert-amyl group, hexyl group, heptyl group, octyl group, iso-octyl group, tert-octyl group, 2-ethylhexyl group, nonyl group, iso-nonyl group, decyl group, iso-decyl group, tert-decyl group, An undecyl group, a dodecyl group, a tert-dodecyl group, etc. are mentioned.
M ₂ represents an alkali metal atom such as Na, K or Li or an alkaline earth metal atom such as Mg or Ca. p represents 1 or 2.

Preferred examples of the phosphoric acid ester metal salt represented by the formula (2) include those in which R ₄ and R ₆ are methyl groups and R ₅ is a tert-butyl group. As a phosphoric acid ester metal salt, trade name, NA-11, manufactured by ADEKA Co., Ltd. can be mentioned. The phosphoric acid ester metal salt can be synthesized by a known method.

As described in JP-A-2003-192884, the compound represented by the formula (1) or (2) is a compound known as a crystal nucleating agent for polylactic acid. However, in the present invention, M ₁ and M ₂ in the formulas (1) and (2) are an alkali metal atom or an alkaline earth metal atom. When M ₁ and M _{2 in the} formulas (1) and (2) are other metals such as aluminum, the heat resistance of the compound itself is low, and a sublimate is generated during spinning, which makes it difficult to spin. There is a case.

  The phosphoric acid ester metal salt (component C) preferably has an average primary particle size of 0.01 to 10 μm, more preferably 0.05 to 7 μm. It is industrially difficult to make the particle size smaller than 0.01 μm, and it is not necessary to make it so small. On the other hand, if it is larger than 10 μm, the frequency of yarn breakage increases during spinning and drawing.

  The content of the phosphoric acid ester metal salt (component C) is 0.01 to 5 parts by weight per 100 parts by weight in total of the poly L-lactic acid (component A) and the poly D-lactic acid (component B), preferably 0.00. 05 to 5 parts by weight, more preferably 0.05 to 4 parts by weight, particularly preferably 0.1 to 3 parts by weight. If the amount is less than 0.01 parts by weight, the desired effect is hardly recognized. On the other hand, if it is used in a larger amount than 5 parts by weight, it is not preferable because thermal decomposition or fiber breakage may occur during fiber formation.

  The ratio of poly L-lactic acid (component A) to poly D-lactic acid (component B) is component A / component B (weight), preferably 40 / 60-60 / 40, more preferably 45 / 55-55. / 45, more preferably 50/50.

  For mixing the A component, the B component, and the C component, various conventionally known methods can be used. For example, the A component, the B component, and the C component can be mixed with a tumbler, a V-type blender, a super mixer, a nauta mixer, a Banbury mixer, a kneading roll, a monoaxial or biaxial extruder, and the like.

  The polylactic acid composition thus obtained can be melt-mixed and transferred to the spinning device as it is or via a metering pump or the like. The temperature for melting and mixing is preferably higher than the melting point of the resulting stereocomplex polylactic acid, and preferably higher than 220 ° C. Further, it may be once pelletized and then supplied to the spinning device. The pellet length is preferably 1 to 7 mm, the major axis is 3 to 5 mm, and the minor axis is 1 to 4 mm. The pellet shape is preferably uniform. The pelletized composition can be transferred to a spinning device using a normal melt extruder such as a pressure melter type or a single-screw or twin-screw extruder type. In forming the stereocomplex crystal, it is important to sufficiently mix the A component and the B component, and it is particularly preferable to mix them under shear stress.

  In the polylactic acid composition, a carboxyl group end-capping agent having a specific functional group can be suitably applied as a wet heat resistance improver. As such a carboxyl terminal blocking agent, it is preferable to use at least one compound selected from an epoxy compound, a carbodiimide compound, an oxazoline compound, an oxazine compound, and an isocyanate compound. By containing the terminal carboxyl group terminal blocking agent, not only the effect of improving the heat and moisture resistance can be improved, but also a fiber excellent in spinnability, mechanical properties, heat resistance and durability can be obtained.

  Here, as an epoxy compound, a glycidyl ether compound, a glycidyl ester compound, a glycidyl amine compound, a glycidyl imide compound, a glycidyl amide compound, and an alicyclic epoxy compound can be preferably used.

  Examples of the carbodiimide compound include dicyclohexylcarbodiimide, diisopropylcarbodiimide, dimethylcarbodiimide, diisobutylcarbodiimide, dioctylcarbodiimide, octyldecylcarbodiimide, di-t-butylcarbodiimide, t-butylisopropylcarbodiimide, dibenzylcarbodiimide, N-octacarbodiimide, -N'-phenylcarbodiimide, N-benzyl-N'-phenylcarbodiimide, N-benzyl-N'-tolylcarbodiimide, di-o-toluylcarbodiimide, di-p-toluylcarbodiimide, bis (p-nitrophenyl) carbodiimide, Bis (p-aminophenyl) carbodiimide, bis (p-hydroxyphenyl) carbodiimide, bis (p- Lorophenyl) carbodiimide, bis (o-chlorophenyl) carbodiimide, bis (o-ethylphenyl) carbodiimide, bis (p-ethylphenyl) carbodiimide bis (o-isopropylphenyl) carbodiimide, bis (p-isopropylphenyl) carbodiimide, bis (o -Isobutylphenyl) carbodiimide, bis (p-isobutylphenyl) carbodiimide, bis (2,5-dichlorophenyl) carbodiimide, p-phenylenebis (o-toluylcarbodiimide), p-phenylenebis (cyclohexylcarbodiimide, p-phenylenenebis ( p-chlorophenylcarbodiimide), 2,6,2 ′, 6′-tetraisopropyldiphenylcarbodiimide, hexamethylenebis (cyclohexylcarbodiimide), Tylene bis (phenylcarbodiimide), ethylene bis (cyclohexylcarbodiimide), bis (2,6-dimethylphenyl) carbodiimide, bis (2,6-diethylphenyl) carbodiimide, bis (2-ethyl-6-isopropylphenyl) carbodiimide, bis ( 2-butyl-6-isopropylphenyl) carbodiimide, bis (2,6-diisopropylphenyl) carbodiimide, bis (2,6-di-t-butylphenyl) carbodiimide, bis (2,4,6-trimethylphenyl) carbodiimide, Bis (2,4,6-triisopropylphenyl) carbodiimide, bis (2,4,6-tributylphenyl) carbodiimide, di-β-naphthylcarboimide, N-tolyl-N′-cyclohexylcarbosiimide, N— Thrill Mono- or di-carbodiimide compounds such as N'- phenyl carbocyclylalkyl imide and the like.

  Of these, bis (2,6-diisopropylphenyl) carbodiimide and 2,6,2 ', 6'-tetraisopropyldiphenylcarbodiimide are preferred from the viewpoints of reactivity and stability. Of these, industrially available dicyclohexylcarbodiimide and diisopropylcarbodiimide are also suitable.

  Also, poly (1,6-cyclohexanecarbodiimide), poly (4,4′-methylenebiscyclohexylcarbodiimide), poly (1,3-cyclohexylenecarbodiimide), poly (1,4-cyclohexylenecarbodiimide), poly (4 , 4′-diphenylmethanecarbodiimide), poly (3,3′-dimethyl-4,4′-diphenylmethanecarbodiimide), poly (naphthylenecarbodiimide), poly (p-phenylenecarbodiimide), poly (m-phenylenecarbodiimide), poly Examples thereof include polycarbodiimides such as (p-tolylcarbodiimide), poly (diisopropylcarbodiimide), poly (methyldisopropylphenylenecarbodiimide), and poly (triethylphenylenecarbodiimide).

  As the commercially available polycarbodiimide compound, for example, “Carbodilite” marketed by Nisshinbo Co., Ltd. can be used. Specifically, “Carbodilite” LA-1 sold as a polylactic acid resin modifier, or polyester “Carbodilite” HMV-8CA sold as a resin modifier can be exemplified.

  A carbodiimide compound can also be manufactured by a conventionally well-known method. For example, it can be produced by subjecting an organic isocyanate to a decarboxylation condensation reaction in a solvent-free or inert solvent at a temperature of 70 ° C. or higher using an organic phosphorus compound or an organometallic compound as a catalyst. The polycarbodiimide compound may be a conventionally known method for producing a polycarbodiimide compound, for example, US Pat. No. 2,941,956, Japanese Examined Patent Publication No. 47-33279, J. Pat. Org. Chem. 28, 2069-2075 (1963), Chemical Review 1981, Vol. 81 no. 4, p619-621 and the like.

  The content of the carboxyl group terminal blocking agent is preferably 0.1 to 5.0 parts by weight, more preferably 0.5 to 2.0 parts by weight, per 100 parts by weight of the polylactic acid composition. A polylactic acid fiber containing a carboxyl group end-capping agent in such a range has a molecular weight retention of 95% or more after treatment for 30 minutes in boiling water at 100 ° C., and a more preferable fiber can be obtained.

  In the present invention, the polylactic acid filament is a filament composed of the above-mentioned polylactic acid composition, and preferably has a stereoization rate of 90% or more by wide-angle X-ray diffraction (XRD) measurement. The fiber strength is preferably 2.3 cN / dtex or more in terms of tensile strength. Moreover, it has a single melting peak in a differential scanning calorimeter (DSC) measurement, and it is preferable that this melting peak temperature is 195 degreeC or more.

  Such a polylactic acid filament can be produced, for example, by the following method. That is, the polylactic acid composition is melted with an extruder type or pressure melter type melt extruder, weighed with a gear pump, filtered in a pack, and then monofilament, multifilament, etc. from a nozzle provided on the base Discharged and spun as. At that time, the number of ejection holes is not particularly limited. The discharged yarn is immediately cooled and solidified, then converged, added with oil, and wound. The spinning speed is not particularly limited, but a range of 300 to 5000 m / min is preferable because a stereocomplex crystal is easily formed. In particular, from the viewpoint of drawability, a spinning speed at which the stereo ratio of the undrawn yarn is 0% is preferable. The wound undrawn yarn is then subjected to a drawing step, but the spinning step and the drawing step are not necessarily separated from each other. Even if a direct spinning drawing method is used in which the drawing is continued without being wound once after spinning. Good. Such undrawn yarn is substantially amorphous as measured by wide-angle X-ray diffraction. Further, when the differential scanning calorimeter (DSC) measurement is performed, at least two endothermic peaks of the low-temperature crystal melting phase (A) and the high-temperature crystal melting phase (B) are not exhibited, and the stereocomplex crystal is substantially A single melting peak is shown. Such melting peak temperature is 195 ° C. or higher. That is, it is estimated that the undrawn yarn forms an amorphous stereocomplex but does not contain a poly L-lactic acid phase and / or a poly D-lactic acid phase capable of forming a low-temperature crystal phase. These characteristics are useful properties that have never been expected in the past due to the fact that the fiber contains a phosphoric acid ester metal salt (component C).

Not having a crystalline phase of poly-L-lactic acid or poly-D-lactic acid at the stage of undrawn yarn is effective for obtaining a high stereo ratio after the subsequent drawing step.
The stretching may be one-stage or multi-stage stretching of two or more stages. From the viewpoint of producing a high-strength fiber, the draw ratio is preferably 3 times or more, more preferably 4 times or more, and further preferably 3 to 10 times. It is. However, if the draw ratio is too high, the fiber is devitrified and whitened, so that the strength of the fiber is lowered. Preheating for stretching can be performed by using a flat plate or pin-shaped contact heater, non-contact heater, heating medium bath, etc., in addition to raising the temperature of the roll. The stretching temperature is preferably 70 to 140 ° C, more preferably 80 to 130 ° C. Even in the drawn yarn, substantially no low-temperature crystal melt phase (A) is observed, and only a single melt peak of the high-temperature crystal melt phase (B) is observed. Further, the melting start temperature of the high-temperature crystal melting phase (B) of the drawn yarn is 190 ° C. or higher, preferably 200 ° C. or higher. In addition, the stereoization rate (Sc rate) obtained from the integrated intensity of the stereocomplex crystal diffraction peak by wide-angle X-ray diffraction measurement of the drawn yarn is at a high level of 90% or more.

  Furthermore, it is preferable to heat-treat the drawn yarn. The heat treatment is performed at 170 to 220 ° C. (preferably 180 to 200 ° C.). The heat treatment is preferably performed under tension. The heat treatment can be performed with a hot roller, a contact heater, a non-contact hot plate or the like. By heat-treating, a polylactic acid filament having a high stereo ratio, excellent heat resistance and iron resistance, and high fiber strength can be obtained.

  The dyed polylactic acid knitted fabric of the present invention is obtained by dyeing a knitted fabric containing the polylactic acid filament. At that time, the single yarn fiber fineness, total fineness, and number of single yarns of the polylactic acid filament are as follows: single yarn fiber fineness of 0.1 to 6.0 dtex (more preferably 0.5 to 2.5 dtex), total fineness of 20 to 300 dtex ( More preferably, it is within the range of 30 to 100 dtex) and the number of single yarns of 4 to 200 (more preferably 12 to 150, particularly preferably 30 to 150). Further, the cross-sectional shape of the single yarn fiber is not limited, and may be an irregular cross-sectional shape such as a triangular shape, a flat shape, a constricted flat shape, a cross shape, a hexagonal shape, or a hollow shape in addition to a normal circular cross section.

Here, it is important that the polylactic acid filament is untwisted or has a twist coefficient defined by the following formula of 300 or less. If the twist coefficient is larger than 300, the soft texture of the knitted fabric may be impaired, which is not preferable.
Twist factor = (twist number (T / m) / (fineness (dtex) ^1/2

  In addition, when knitting a knitted fabric, it is most preferable to use only the polylactic acid filaments described above, but if it is 30% by weight or less with respect to the knitted fabric weight, other fibers such as polyethylene terephthalate fibers are used. May be.

  The woven structure of the knitted fabric is not particularly limited, and may be a circular knitted fabric (weft knitted fabric) or a newly knitted fabric. Preferred examples of the structure of the circular knitted fabric (weft knitted fabric) include a flat knitted fabric, rubber knitted fabric, double-sided knitted fabric, pearl knitted fabric, tucked knitted fabric, float knitted fabric, one-sided knitted fabric, lace knitted fabric, and bristle knitted fabric. Examples include a single denby knitting, a single atlas knitting, a double cord knitting, a half tricot knitting, a back hair knitting, and a jacquard knitting. The number of layers may be a single layer or a multilayer of two or more layers. Furthermore, it may be a raised fabric composed of a raised portion made of a cut pile and / or a loop pile and a ground tissue portion.

  The conditions for the dyeing process are not particularly limited, and may be a dyeing process using a normal disperse dye. For example, the dyeing treatment may be performed at a temperature of 100 ° C. or higher (preferably 100 to 140 ° C.) for 20 to 40 minutes with a dye aqueous solution containing a leveling agent, a pH adjuster, etc. in addition to the disperse dye. The dye used for dyeing is preferably an azo-based disperse dye having good washing fastness, but is not particularly limited. Among these, disperse dyes that are easily decomposed in a cleaning treatment liquid described later are preferably disperse dyes having a diester group, azo disperse dyes, among which thiazole type and thiophene type, but are not particularly limited. Further examples include anthraquinone-based disperse dyes, benzodiphyranone-type disperse dyes, and disperse dyes having an alkylamine group.

  Subsequently, it is preferable to perform a reduction cleaning process on the dyed knitted fabric. At that time, it is preferable to carry out a reduction cleaning treatment in a reducing bath of pH 8-2. In an alkaline region larger than ph8, the polylactic acid fiber may be hydrolyzed and the fiber strength may be reduced.

  Examples of the reducing agent include a tin-based reducing agent, Rongalite C, Rongalit Z, stannous chloride, a sulfine-based reducing agent, and hydrosulfite. The use concentration of the reducing agent is preferably 1 to 10 g / L, and the concentration may be selected according to the type of dye used, the dyeing concentration, and the reducing bath temperature. Although the processing temperature of a reducing bath is not specifically limited, The range of 60-98 degreeC is preferable, and the processing time is 10 to 40 minutes.

  Further, in the treatment in the reducing bath, as a fiber swelling agent, generally used carriers such as chlorobenzene carrier, methylnaphthalene carrier, orthophenylphenol carrier, aromatic ether carrier, aromatic ester A carrier or the like may be used. Examples of the fiber swelling agent include polyoxyethylene alkyl allyl ether, polyoxyethylene alkyl amine, polyoxyethylene alkyl phenol ether, polyoxyethylene alkyl ether, polyoxyethylene alkyl amine ether, polyoxyethylene alkyl allyl ether, polyoxyethylene alkyl amine, polyoxyethylene alkyl phenol ether, Examples include, but are not limited to, ethylene alkyl benzyl ammonium chloride and alkyl picolinium chloride.

  In the dyed polylactic acid knitted fabric thus obtained, it is important that the number of loops per square 2.54 cm is in the range of 200 to 10,000. If the number of loops is less than 200, the knitted fabric may be squeezed and the appearance may be impaired. On the contrary, if the number of loops is larger than 10,000, the soft texture of the knitted fabric may be impaired, which is not preferable.

  The dyed knitted fabric of the present invention is a knitted fabric containing polylactic acid filaments excellent in heat resistance as described above, so that it can be dyed at high temperatures and has excellent deep color properties. The deep color is preferably 15 or less in terms of L value. Moreover, since the density of the knitted fabric is within a specific range, a soft texture is exhibited.

  The dyed knitted fabric of the present invention has functions such as a conventional water-repellent finish, brushed finish, ultraviolet shielding or antibacterial agent, deodorant, insect repellent, phosphorescent agent, retroreflective agent, negative ion generator, etc. Various processes for imparting may be additionally applied.

  Next, the apparel of the present invention is an apparel using the dyed knitted fabric. Such clothing includes sports clothing, nifoam clothing, shirts, blousons, pants, coats, and the like. Since such garments include the dyed knitted fabric, they exhibit deep color and soft texture.

  In addition, the dyed knitted fabric is a vehicle interior material such as a car seat skin material, a floor material, a ceiling material, a clothing material such as a cup and a pad, an interior product such as a curtain, carpet, mat, and furniture, Industrial materials such as belts, nets, ropes, heavy cloths, bags, felts, filters, accessories, form straps, glasses wipes, dish wipes, mouse pads, plush toys, toys, hats, gloves, whiteboard cleaners, notebook covers It is also suitably used as small items such as.

  Hereinafter, although the present invention is explained using an example, the present invention is not limited to this example. In addition, the physical property in an Example was measured with the following method.

(1) Weight average molecular weight (Mw)
The weight average molecular weight of the polymer was determined by GPC (column temperature 40 ° C., chloroform) in comparison with a polystyrene standard sample.

(2) Stereo conversion rate (Sc conversion rate)
An X-ray diffraction pattern was recorded on an imaging plate by the transmission method using a ROTA FLEX RU200B type X-ray diffractometer manufactured by RIKEN. In the obtained X-ray diffraction pattern, a diffraction intensity profile in the equator direction is obtained. Here, the integrated intensity of each diffraction peak derived from the stereocomplex crystal appearing in the vicinity of 2θ = 12.0 °, 20.7 °, and 24.0 °. Was obtained from the total intensity ΣI _SCi and the integrated intensity I _HM of the diffraction peak derived from the homocrystal appearing in the vicinity of 2θ = 16.5 ° in accordance with the following formula. Incidentally, as shown in FIG. 1, ΣI _SCi and I _HM were estimated by subtracting diffuse scattering due to background or amorphous in the diffraction intensity profile in the equator direction.
X-ray source: Cu-Kα ray (confocal mirror)
Output: 45kV x 70mA
Slit: 1mmΦ ~ 0.8mmΦ
Camera length: 120mm
Integration time: 10 minutes Sample: 3cm length, 35mg
Sc conversion rate = ΣI _SCi / (ΣI _SCi + I _HM ) × 100
Here, ΣI _SCi = I _SC1 + I _SC2 + I _SC3
I _SCi (i = 1 to 3) is 2θ = 12.0 °, 20.7 °,
Integrated intensity of each diffraction peak around 24.0 °

(3) Melting point, crystal melting peak, crystal melting start temperature, crystal melting enthalpy measurement:
TA-2920 differential scanning calorimeter DSC manufactured by TA Instruments was used.
In the measurement, 10 mg of a sample was heated from room temperature to 260 ° C. at a heating rate of 10 ° C./min in a nitrogen atmosphere. In the first scan, the homocrystal melting peak, homocrystal melting (starting) temperature, homocrystal melting enthalpy and stereocomplex crystal melting peak, stereocomplex crystal melting (starting) temperature and stereocomplex crystal melting enthalpy were determined.

(4) Fiber strength (cN / dtex)
Using “Tensilon” (trade name) manufactured by Orientic Corporation, ten target single yarns (filaments) are randomly extracted from the fiber structure to be measured, the yarn sample length is 50 mm (length between chucks), and the elongation speed is 500 mm. The strain-stress curve was measured under the conditions of an atmospheric temperature of 20 ° C. and a relative humidity of 65% under the conditions of / min, and after obtaining the strength (cN / piece) from the stress and elongation at the breaking point, the strength was divided by the fineness. The fiber strength (cN / dtex).

(5) Texture evaluation Sensory evaluation was performed on the soft feeling by three testers and evaluated in three stages. “Excellent” was shown in the third grade, “Normal” in the second grade, and “Inferior” in the first grade.

(6) Number of loops A square sample having a side of 2.54 cm was taken in the same direction as the length and width of the knitted fabric, and the number of loops per square 2.54 cm was counted using a microscope.

[Production Example 1] (Production of poly L-lactic acid)
To 100 parts by weight of L-lactide (manufactured by Musashino Chemical Laboratory, Inc., 100% optical purity), 0.005 part by weight of octyltinate was added, and the reaction was performed at 180 ° C. in a nitrogen atmosphere in a reactor equipped with a stirring blade. After reacting for 2 hours, phosphoric acid equivalent to 1.2 times the amount of tin octylate was added, and then the remaining lactide was removed at 13.3 kPa to obtain chips to obtain poly L-lactic acid.
The obtained L-lactic acid had a weight average molecular weight of 150,000, a glass transition point (Tg) of 63 ° C., and a melting point of 180 ° C.

[Production Example 2] (Production of poly-D-lactic acid)
To 100 parts by weight of D-lactide (manufactured by Musashino Chemical Laboratory, Inc., 100% optical purity), 0.005 part by weight of tin octylate was added, and the reactor was stirred at 180 ° C. with a stirring blade in a nitrogen atmosphere. After reacting for 2 hours, phosphoric acid equivalent to 1.2 times the amount of tin octylate was added, and then the remaining lactide was removed at 13.3 kPa to obtain chips. Poly D-lactic acid was obtained. The weight average molecular weight was 150,000, the glass transition point (Tg) was 63 ° C., and the melting point was 180 ° C.

[Production Example 3] (Production of stereocomplex polylactic acid resin)
50 parts by weight of each of the poly L-lactic acid obtained in Production Example 1 and the poly D-lactic acid in Production Example 2, and phosphate metal salt (ADEKA (former: Asahi Denka Kogyo Co., Ltd.) ADK STAB NA-11) ) 0.5 parts by weight was melt-kneaded at 230 ° C., and 0.7 parts by weight of Nisshinbo Carbodilite LA-1 as the carbodiimide per 100 parts by weight of the total of poly L-lactic acid and poly D-lactic acid was supplied first. The mixture was supplied from the mouth and kneaded and extruded at a cylinder temperature of 230 ° C., and the strand was taken into a water tank and chipped with a chip cutter to obtain a stereocomplex polylactic acid resin. Mw of the obtained stereocomplex polylactic acid resin was 135,000, melting | fusing point (Tm) was 224 degreeC, and the stereoification rate was 100%.

[Example 1]
The stereocomplex polylactic acid resin obtained in Production Example 3 was dried at 110 ° C. for 2 hours and at 150 ° C. for 5 hours to give a moisture content of the resin of 80 ppm, and then a spinneret having 36 holes of 0.27 φmm was formed. The undrawn yarn was wound up at a speed of 500 m / min after spinning at a spinning temperature of 255 ° C. and a discharge rate of 8.35 g / min. The wound undrawn yarn was drawn 4.9 times with a drawing machine at 80 ° C. by preheating to wind the drawn yarn, and then heat treated at 180 ° C. The process passability in the spinning process and the drawing process was good, and the wound drawn yarn was a multifilament having a fineness of 167 dTex / 36 fil, a strength of 3.6 cN / dTex, an elongation of 35%, and a melting point of 213 ° C. . Moreover, it had a single melting peak in DSC measurement, the melting peak temperature (melting point) was 224 ° C., and the stereoification rate was 100%.

After knitting a tentacle knitted fabric using the obtained stereocomplex polylactic acid filament, the knitted fabric was set at 150 ° C. for 2 minutes by dry heat, and then 20 ° C. at 120 ° C. using a liquid dyeing machine. Minute staining was performed. At that time, a black disperse dye was used. Furthermore, a dry heat set at a temperature of 160 ° C. for 2 minutes was performed.
In the obtained knitted fabric, the number of loops per square 2.54 cm (1 inch) was 4,200, and the texture was grade 3 and the L value was 13.4.

[Example 2]
After the multi-filament of stereocomplex polylactic acid filament 84dTex36fil obtained in the same manner as in Example 1 was knitted into a tense knitted fabric, the knitted fabric was dry heat set at a temperature of 150 ° C. for 2 minutes, and then a liquid dyeing machine was used. And dyeing was performed at 120 ° C. for 20 minutes. At that time, a black disperse dye was used. Furthermore, a dry heat set at a temperature of 160 ° C. for 2 minutes was performed.
In the obtained knitted fabric, the number of loops per square 2.54 cm (1 inch) was 8400, and the texture was grade 3 and the L value was 14.4.

[Comparative Example 1]
In Example 1, it carried out similarly to Example 1 except using the poly L-lactic acid obtained in manufacture example 1 instead of the stereocomplex polylactic acid resin.
The melting point of the polylactic acid filament was 180 ° C. The obtained knitted fabric contracted due to the heat history during dyeing and became hard (texture 1st grade). Further, the texture was hard and it was difficult to accurately measure the L value with a measuring instrument, but the apparent deep color was insufficient.

[Comparative Example 2]
Example 1 was the same as Example 1 except that the gauge of the knitting machine was changed to a high gauge.
In the obtained knitted fabric, the number of loops per square inch 2.54 cm (1 inch) was 11200, and although the deep color was obtained with the texture level 1 and the L value of 15.1, the texture was hard and not sufficient.

[Reference Example 1]
As a phosphoric acid ester metal salt, aluminum bis (2,2′-methylenebis (4,6-ditertiarybutylphenyl) phosphate) hydroxide (ADEKA STAB NA-21 manufactured by ADEKA Corporation (formerly Asahi Denka Kogyo Co., Ltd.)) When the same operation as in Example 1 was performed except that 0.5 part by weight was used, a sublimation product was vigorously generated during spinning, and it was difficult to perform spinning.

  ADVANTAGE OF THE INVENTION According to this invention, the polylactic acid knitted fabric containing the polylactic acid fiber excellent in deep color property without impairing the texture of a knitted fabric, its manufacturing method, and clothing are provided, The industrial value is very large.

In an Example, an example of the diffraction intensity profile of the equatorial direction for calculating | requiring a stereoization rate (Sc rate) is shown.

Claims (7)

(I) poly L-lactic acid (component A), (ii) poly D-lactic acid (component B) and (iii) 0.05 to 5 parts by weight of the following formula per 100 parts by weight of the total of components A and B ( A step of melt spinning the polylactic acid composition containing the phosphoric acid ester metal salt (component C) represented by 1) or (2) to obtain an undrawn yarn, and a step of obtaining an undrawn yarn at 70 to 140 ° C. and drawn yarn to facilities the dyeing polylactic acid knitted fabric comprising a polylactic acid filament obtained by heat treating at 170 to 220 ° C., and the knitted fabric after dyeing, the number of loops per square 2.54 cm 200 A method for producing a dyed polylactic acid knitted fabric , characterized in that it is within a range of 10000 pieces.

In the formula, R ₁ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ₂ and R ₃ each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and M ₁ represents an alkali metal atom or Represents an alkaline earth metal atom, and p represents 1 or 2.

In the formula, each of R ₄ , R ₅ and R ₆ independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, M ₂ represents an alkali metal atom or an alkaline earth metal atom, and p represents 1 or 2 Represents. The polylactic acid composition contains 0.1 to 5 parts by weight of a carboxyl terminal blocking agent per 100 parts by weight in total of a poly L-lactic acid component (A component) and a poly D-lactic acid component (B component). The method for producing a dyed and processed polylactic acid knitted fabric according to claim 1. The method for producing a polylactic acid knitted fabric dyed and processed according to claim 1 or 2, wherein a single yarn fineness of the polylactic acid filament is in a range of 0.1 to 6.0 dtex. The method for producing a dyed polylactic acid knitted fabric according to any one of claims 1 to 3, wherein the knitted fabric is composed of only the polylactic acid filaments. The L value of the knitted fabric after dyeing is 15 or less, the production method of dyeing polylactic acid knitted fabric according to any one of claims 1 to 4. A method of manufacturing a stainer processed polylactic acid knitted fabric according to any one of claims 1 to 5, the temperature of dyeing is in the range of 100 to 140 ° C., the production of dyeing polylactic acid knitted fabric Method. Obtaining a garment using a polylactic acid knitted fabric obtained by the production method described in any one of claims 1-6, clothing manufacturing method.

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