JP2008190060A - Wiping cloth - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wiping cloth of environment consideration type which is obtained by using a core-sheath type conjugate fiber including a core part composed of a biomass polymer and a sheath part composed of a petroleum-based polymer and has excellent moist heat resistance, dry heat resistance and color fastness. <P>SOLUTION: The wiping cloth is obtained by using a core-sheath type conjugate fiber comprising a core part composed of a biomass polymer and a sheath part composed of a petroleum-based polymer and has tenacity retention rate (ratio) of the core-sheath type conjugate fiber after treatment for 500 hours in the environment at 50°C×95%RH of ≥85%, and color fastness to friction of fourth class or higher. In the wiping cloth, a polylactic acid is preferable as the biomass polymer and a polyethylene terephthalate is preferable as the petroleum-based polymer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a wiping cloth that is excellent in moisture and heat resistance, dry heat resistance and dyeing fastness, and can reduce the amount of carbon dioxide generated at the stage of production to disposal.

  Conventionally, synthetic fibers have been widely used from the viewpoint of versatility, and are used in various fields.

  However, synthetic fibers are mainly made from limited precious fossil resources such as petroleum, and there are concerns about future resource shortages. In addition, it is hardly decomposed in the natural environment, and when it burns, it generates high heat, causing problems such as severe damage to the incinerator. Yes. For this reason, the idea that reducing the amount of petroleum-based synthetic fibers used in the industry itself is environmental protection is spreading.

  In recent years, biomass polymers have attracted attention in terms of carbon neutral, which absorbs carbon dioxide at the stage of procuring a plant as a raw material, and offsets even if carbon dioxide is generated during combustion. Therefore, development of fiber products using biomass polymers has been extensively performed.

As an example, Patent Document 1 discloses a wiping cloth using polylactic acid ultrafine fibers.
JP 2001-192932 A

  Synthetic fibers made of biomass polymer are used not only for clothing but also for materials. However, there is a problem that physical properties and dyeing fastness are difficult to maintain when using laundry or ironing.

  Further, in the above applications, a high level of tear strength and burst strength, wear resistance, dimensional stability and the like that are not problematic in practice are required. However, when the synthetic fiber is used, there is a problem that the strength decreases due to the influence of wet heat treatment such as scouring and dyeing and dry heat treatment such as drying and heat setting. That is, the synthetic fiber made of biomass polymer has the disadvantages that it is inferior in mechanical properties and dyeing fastness such as friction fastness to petroleum synthetic fiber.

  Further, there is a problem that the fibers are gradually deteriorated and the strength is lowered by exposing them to sunlight in a wet state, or leaving them in a high temperature environment such as in a car or outdoors, or repeating tumbler drying. Especially in the case of wiping cloth, such a tendency significantly impairs the commercial value.

  The present invention solves the above-mentioned problem, and uses a core-sheath type composite fiber having a core part made of biomass polymer and a sheath part made of a petroleum-based polymer, and is resistant to moist heat resistance, dry heat resistance and dyeing fastness. It provides an environmentally friendly wiping cloth that is superior to the above.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have used a core-sheath type composite fiber in which the core part is made of a biomass polymer and the sheath part is made of a petroleum-based polymer. The inventors have found that a wiping cloth excellent in dyeing fastness can be obtained, and reached the present invention.

That is, the gist of the present invention is as follows.
(1) The strength of the core-sheath composite fiber after treatment for 500 hours in a 50 ° C. × 95% RH environment using a core-sheath composite fiber in which the core part is made of biomass polymer and the sheath part is made of a petroleum polymer. A wiping cloth having a retention of 85% or more and a dyeing fastness to friction of 4 or more.
(2) The wiping cloth according to (1), wherein the petroleum-based polymer is polyethylene terephthalate.
(3) The wiping cloth according to (1), wherein the petroleum polymer is polyethylene terephthalate obtained by copolymerizing at least one component of isophthalic acid, cyclohexanedimethanol, and cyclohexanedicarboxylic acid in an amount of 5 to 20 mol%.
(4) The wiping cloth according to any one of (1) to (3), wherein the biomass polymer is polylactic acid.
(5) The wiping cloth according to any one of claims 1 to 4, wherein the core-sheath type composite fiber is a modified cross-section yarn satisfying the following formulas (1) to (3).

  The wiping cloth of the present invention uses a core-sheath type composite fiber made of biomass polymer. Therefore, compared to a conventional wiping cloth composed only of petroleum-based synthetic fibers, it is possible to reduce the amount of carbon dioxide generated at the stage of production to disposal, and to improve wet heat resistance, dry heat resistance, dyeing fastness, and the like.

  Hereinafter, the present invention will be described in detail.

  In the core-sheath type composite fiber in the present invention, the core part is made of a biomass polymer and the sheath part is made of a petroleum polymer.

  The biomass polymer in the present invention is not particularly limited as long as it can be melt-spun. Specifically, polymers formed by chemically polymerizing monomers derived from biomass such as PLA (polylactic acid), PTT (polytrimethylene terephthalate) and PBS (polybutylene succinate), PHA (polyhydroxybutyric acid) and the like. And microbial production polymers such as alkanoates). Among them, polylactic acid that has stable heat resistance and is relatively mass-produced is preferable. As the polylactic acid, either a homopolymer or a copolymer (hereinafter, this polymer may be referred to as copolymer polylactic acid) can be used. Among these, examples of the homopolymer include poly D-lactic acid, poly L-lactic acid, a mixture of poly D-lactic acid and poly L-lactic acid (stereo complex), and the like. On the other hand, as the copolymerized polylactic acid, poly-DL-lactic acid obtained by copolymerizing poly-D-lactic acid and poly-L-lactic acid, D-lactic acid and / or L-lactic acid and hydroxycarboxylic acid are copolymerized. Examples thereof include polylactic acid, copolymerized polylactic acid obtained by copolymerizing D-lactic acid and / or L-lactic acid, aliphatic dicarboxylic acid and aliphatic diol, or a blend thereof.

  The physical properties of the polylactic acid are preferably a melting point of 120 ° C. or higher and a heat of fusion of 10 J / g or higher. The melting point of poly L-lactic acid and poly D-lactic acid, which are polylactic acid homopolymers, is about 180 ° C. On the other hand, in the copolymerized polylactic acid obtained by copolymerizing D-lactic acid and L-lactic acid, the melting point becomes about 130 ° C. when the proportion of any of the components is about 10 mol%. Further, when the proportion of any of the components is 18 mol% or more, the melting point is less than 120 ° C. and the heat of fusion is less than 10 J / g, and as a result, the film is almost completely amorphous. Such an amorphous state is disadvantageous in obtaining high-strength fibers. Specifically, it becomes difficult to heat-stretch and may affect heat resistance, wear resistance, and the like. Therefore, the L / D or D / L, which is the content ratio of L-lactic acid and D-lactic acid (the molar ratio between L-lactic acid and D-lactic acid when polymerizing using lactide as a raw material), is preferably 82/18 or more. 90/10 or more is more preferable, and 95/15 or more is particularly preferable. Considering the melting point in particular, a mixture (stereo complex) of poly D-lactic acid and poly L-lactic acid is most preferable. In this case, the melting point is 200 to 230 ° C. When the melting point of polylactic acid is increased, the process passability after forming a woven or knitted fabric is improved, and for example, ironing is also possible.

  Moreover, when employ | adopting the copolymerization polylactic acid which copolymerized D-lactic acid and / or L-lactic acid, and hydroxycarboxylic acid as polylactic acid in this invention, glycolic acid, hydroxybutyric acid, hydroxyvaleric acid is used as hydroxycarboxylic acid. Hydroxycaproic acid, hydroxypentanoic acid, hydroxyheptanoic acid, hydroxyoctanoic acid and the like. Of these, glycolic acid and hydroxycaproic acid are preferable in terms of cost.

  Furthermore, when adopting copolymer polylactic acid obtained by copolymerizing D-lactic acid and / or L-lactic acid, aliphatic dicarboxylic acid and aliphatic diol as the polylactic acid in the present invention, as aliphatic dicarboxylic acid and aliphatic diol Examples thereof include sebacic acid, adipic acid, dodecanedioic acid, trimethylene glycol, 1,4-butanediol, 1,6-hexanediol, and the like.

  When employing copolymerized polylactic acid, it is preferable to use a copolymer obtained by copolymerizing 80 mol% or more of D-lactic acid and / or L-lactic acid. If the D-lactic acid and / or L-lactic acid is less than 80 mol%, the crystallinity of the copolymer polymer tends to be low, and the melting point tends to be less than 120 ° C. and the heat of fusion is less than 10 J / g.

  The molecular weight index (melt flow rate) of polylactic acid in the present invention is preferably 1 to 100 g / 10 min, and more preferably 5 to 50 g / 10 min. By setting the melt flow rate within this range, the strength, wet heat decomposability and wear resistance of polylactic acid can be improved. Here, as the melt flow rate, a value measured under conditions of a temperature of 210 ° C. and a load of 2160 g according to the ASTM D-1238 method used as an index of molecular weight is adopted.

  In addition, for the purpose of enhancing the durability of polylactic acid, a terminal blocking agent such as aliphatic alcohol, carbodiimide compound, oxazoline compound, oxazine compound or epoxy compound may be added to polylactic acid.

  On the other hand, the petroleum polymer in the present invention is not particularly limited as long as it can be melt-spun. Specifically, polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate, polytrimethylene terephthalate, polyamides such as nylon 6, nylon 66, nylon 46, nylon 11 and nylon 12, polyolefins such as polypropylene and polyethylene, polychlorinated Examples thereof include chlorine polymers such as vinyl and polyvinylidene chloride, fluorine polymers such as polytetrafluoroethylene and polyvinylidene fluoride, and blends thereof. Of these, polyester and polyamide are preferable in terms of cost. In the present invention, polylactic acid is preferable as the biomass polymer. However, when polylactic acid is employed as described above, it is preferable to employ polyester as the petroleum polymer in consideration of compatibility.

  As the polyester, either a homopolymer or a copolymer (hereinafter, this polymer may be referred to as a copolymer polyester) can be used. When a copolymerized polyester is employed as the polyester, compatibility with the polylactic acid, thermal characteristics, viscosity, and the like can be easily changed by appropriately setting the type and amount of the copolymer component.

  Any copolymerizable component may be used as long as it has ester-forming ability. Specifically, aromatic dicarboxylic acids such as isophthalic acid and 5-sulfoisophthalic acid, aliphatic dicarboxylic acids such as adipic acid, succinic acid, suberic acid, sebacic acid and dodecanedioic acid, ethylene glycol, propylene glycol, 1, Aliphatic diols such as 4-butanediol and 1,4-cyclohexanedimethanol, glycolic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxycaproic acid, hydroxypentanoic acid, hydroxyheptanoic acid, hydroxyoctanoic acid and other hydroxycarboxylic acids, ε -Aliphatic lactones such as caprolactone. Of these, isophthalic acid (IPA), cyclohexanedimethanol (CHDM), and cyclohexanedicarboxylic acid (CHDA) are preferable.

  And when using a copolymer polyester, it is preferable to use the copolymer polyester which copolymerized the said copolymer component preferably 5-20 mol%, More preferably, 5-10 mol%.

  When a copolyester is used, the reaction temperature during the polycondensation reaction may be lowered. Then, the spinning temperature can be lowered. This is advantageous because the thermal decomposition of the core biomass polymer that occurs during spinning can be suppressed, especially when the melting point of the biomass polymer disposed in the fiber core is lower than that of polyethylene terephthalate. Furthermore, by adopting the copolyester, there may be a case where it is possible to suppress a decrease in strength in a high humidity environment such as 50 ° C. × 95% RH.

  Also, as a copolymerized polyester, a copolymer of high degree of polymerization obtained by solid-phase polymerization by heating a melt-polymerized polyester (prepolymer) chip at a temperature below the melting point of the polyester under reduced pressure or under an inert gas flow. When polyester is used, high-strength fibers may be obtained.

  Furthermore, the petroleum polymer and / or biomass polymer may contain additives such as a filler, a thickener, and a crystal nucleating agent as long as the object of the present invention is not impaired. Additives include carbon black, calcium carbonate, silicon oxide and silicate, zinc white, high-site clay, kaolin, basic magnesium carbonate, mica, talc, quartz powder, diatomaceous earth, dolomite powder, titanium oxide, oxidation Aliphatic amide compounds such as zinc, antimony oxide, barium sulfate, calcium sulfate, alumina, calcium silicate, boron nitride, behenamide, aliphatic urea compounds, benzylidene sorbitol compounds, crosslinked polymer polystyrene, rosin metals Examples thereof include salt, glass fiber, and whisker. Of these, inorganic fillers are preferred in consideration of price and physical properties.

  Examples of the additive content in the polymer include an aspect in which the additive is contained as it is, an aspect in which the additive is contained as a nanocomposite, and the like.

  Moreover, the said petroleum-type polymer and / or biomass polymer may contain a plasticizer in the range which does not impair the objective of this invention. By containing a plasticizer in the polymer, it is possible to reduce the melt viscosity at the time of heat processing and to suppress a decrease in molecular weight due to shearing heat generation or the like, and to improve the crystallization speed. Examples of plasticizers include ether plasticizers, ester plasticizers, phthalic acid plasticizers, and phosphorus plasticizers. Among them, ether plasticizers and ester plasticizers are used in consideration of compatibility with polyester. preferable. Here, examples of the ether plasticizer include polyoxyalkylene glycols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. On the other hand, examples of the ester plasticizer include esters of aliphatic dicarboxylic acid and aliphatic alcohol. Examples of the aliphatic dicarboxylic acid include oxalic acid, succinic acid, sebacic acid, adipic acid and the like. Aliphatic alcohols include monohydric alcohols such as methanol, ethanol, n-propanol, isopropanol, n-hexanol, n-octanol, 2-ethylhexanol, n-dodecanol, stearyl alcohol, ethylene glycol, 1,2-propylene glycol 1,3-propylene glycol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, dihydric alcohols such as diethylene glycol, neopentyl glycol, polyethylene glycol, glycerin, trimethylolpropane, penta And polyhydric alcohols such as erystole. In addition, copolymers, di-copolymers, tri-copolymers, tetra-copolymers, or blends thereof composed of a combination of two or more of the above polyethers and polyesters can also be used as plasticizers. As the plasticizer, a hydroxycarboxylic acid compound obtained by esterifying the above compound or a derivative thereof can also be used.

  Further, within the range not impairing the object of the present invention, the petroleum polymer and / or biomass polymer is a colorant such as pigment or dye, an odor absorbent such as activated carbon or zeolite, a fragrance such as vanillin or dextrin, or an antioxidant. Further, it may contain a stabilizer such as an ultraviolet absorber, a lubricant, a release agent, a water repellent, an antibacterial agent and other secondary additives.

  In addition, the petroleum polymer and / or biomass polymer may contain a compatibilizing agent for the purpose of improving the compatibility at the composite interface between the sheath and the core, as long as the object of the present invention is not impaired. Good. As the compatibilizing agent, a material compatible with the biomass polymer and the petroleum-based polymer can be used. For example, a surfactant copolymer or a block copolymer can be used. Furthermore, a crosslinking agent that reacts with both polymers can also be used. For example, an epoxy compound having an epoxy group at both ends, an oxazoline compound, an oxazine compound and a copolymer thereof, a carbodiimide compound and a copolymer thereof, and the like can be given.

  The core-sheath type composite fiber according to the present invention has a core part made of a biomass polymer and a sheath part made of a petroleum polymer, and the core / sheath ratio (mass ratio) is: core / sheath = 20/80 to 80/20. Preferably there is. When the core-sheath ratio is less than 20/80, the ratio of the core biomass polymer is decreased, and the carbon dioxide reduction effect and the like tend to be reduced. On the other hand, when the core-sheath ratio is 80/20 or more, the strength retention of the wiping cloth tends to decrease, which is not preferable.

  Next, the form of the core-sheath type composite fiber in the present invention is not particularly limited, and any of staple, shortcut fiber, and filament may be used, and the filament may be monofilament or multifilament. Further, it may be used as a flat yarn, false twisted yarn, knitted knitted yarn, fluid ejection processed yarn, or twisted yarn obtained using a double twister or a ring twisting machine. Of course, there is no problem even if it is in the form of a composite yarn obtained by means of blending, fiber blending or the like. Further, the fiber cross-sectional shape may be an elliptical cross-section, a triangular cross-section, an irregular cross-section such as an uneven cross-section, in addition to a round cross-section.

  The form of the core-sheath type composite fiber in the present invention can be arbitrarily set as described above, but the cross-sectional shape is preferably a modified cross-section yarn from the viewpoint of water absorption / diffusion performance. Accompanying false twisted yarn is preferred. As specific atypical characteristics of the atypical cross section, it is preferable that the following formulas (1) to (3) are satisfied.

Since CS is 1.5 or more, S _1.5 is 50% or more, and S _1.8 is 20% or more, the bending rigidity of the false twisted yarn is reduced, and the slimy feeling is eliminated. A wiping cloth with excellent fit and usability can be obtained. Here, as a more preferable range, CS is 1.6 or more, _S1.5 is 60% or more, and _S1.8 is 25% or more. Moreover, it is also a preferable aspect that S _2.0 represented by the number of filaments having a cross-sectional deformation ratio of 2.0 or more / the total number of filaments × 100 is 10% or more. In this case, the above effect is further promoted. Is done.

In the above formulas (1) to (3), the upper limit is not particularly limited, but if it is excessively large, a feeling of roughness may occur. Therefore, it is preferable that CS is 2.5 or less, S _1.5 is 100% or less, and S _1.8 is 70% or less.

  Here, the average cross-sectional deformation rate (CS) is a numerical value obtained by photographing a cross section of a yarn, measuring the cross-sectional deformation rates of all filaments, and calculating the average value. However, when the number of filaments exceeds 80, the section deformation rate of 80 selected at random is measured, and the average value is calculated. The cross-sectional deformation rate of each filament is represented by the diameter ratio of the circumscribed circle and the inscribed circle in the cross section.

S _1.5 , S _1.8 and S _2.0 are numerical values calculated by the above formulas (1) to (3) by measuring the cross-sectional deformation rate of each filament according to the above method. is there.

  Moreover, as a strong retention rate of the said core-sheath-type composite fiber, it is preferable that the intensity | strength after being immersed in a 130 degreeC water bath for 30 minutes is hold | maintained 70% or more with respect to before immersion.

  In general, a wiping cloth tends to require antifouling properties and palatability, and is usually used after being dyed. In the core-sheath type composite fiber, since different polymers are disposed in the core part and the sheath part, optimum dyeing conditions exist for each. For example, in the case of polylactic acid, it is preferable to dye in a water bath at 100 to 110 ° C. for 15 to 60 minutes. On the other hand, in the case of polyethylene terephthalate, it is preferable to dye in a water bath at 125 to 135 ° C. for 15 to 60 minutes.

In general, the higher the dyeing temperature, the greater the damage to the fibers. Therefore, in the present invention, it is preferable not to raise the dyeing temperature so much. If the dyeing temperature is raised too much, the fiber strength retention rate may be less than 70%, and the fiber strength decreases during dyeing. When used as a wiping cloth, the burst strength, tear strength, tensile strength, etc. Is not preferred because it tends to be unsuitable for practical use. On the other hand, even if the dyeing temperature is lowered too much for the purpose of suppressing the decrease in strength, the color development required as a wiping cloth tends to be poor. In the present invention, the dyeing temperature is preferably around 130 ° C.
The wiping cloth of the present invention is formed by using the above-described core-sheath type composite fiber, and it is necessary that the strength retention after treatment for 500 hours in a 50 ° C. × 95% RH environment is 85% or more.

  Here, the tenacity retention is the cutting strength (fiber strength) of fibers taken out from the woven or knitted fabric after being treated for 500 hours in a 50 ° C. × 95% RH environment. This is a numerical value indicating the level of cutting strength (fiber strength). Specifically, the fibers are taken out from the woven or knitted fabric before and after the treatment for 500 hours, the respective fiber strengths are measured according to JIS L-1013, and the strength retention is calculated according to the following formula (a).

  When the strength retention is less than 85, the heat and moisture resistance and the dry heat resistance are inferior. That is, a mode in which heat is applied in a wet state or a dry state, for example, a wiping cloth that is exposed to sunlight while wearing the wiping cloth in a wet state, or left in a high temperature environment such as in a car or outdoors in a wet state. Repeating washing and drying, and using a tumbler dryer to dry the wiping cloth, the fiber gradually deteriorates, and the strength of the wiping cloth decreases.

  Further, the wiping cloth of the present invention preferably has a dyeing fastness to friction of 4th or higher. The dyeing fastness to friction here refers to a value measured according to JIS L-0849. Specifically, as a test piece (220 × 30 mm) in the friction tester type 2, a woven or knitted fabric is set on a test piece base and a white cotton cloth for friction is attached to the tip of the friction element, and the test piece is 100 mm with a load of 2N. The fastness of the woven or knitted fabric is determined by reciprocating 100 times at a speed of 30 reciprocations per minute and comparing the degree of coloring of the white cotton fabric for friction with the gray scale. In the present invention, both the 7.1 dry test and the 7.2 wet test need to be grade 4 or higher.

  When only fibers composed only of biomass polymer are used for the wiping cloth, the friction fastness of the wiping cloth is deteriorated. Specifically, when dyed in a dark color with an L * value of less than 50, the fastness to friction in the dry state is at the level 2-3, which is not suitable for practical use. The wiping cloth may be used not only in a dry state (dry wiping) but also in a wet state (including moisture and a cleaning agent), and it is preferable that the fastness to friction is high in both the dry state and the wet state. In the wiping cloth of the present invention, by using the core-sheath type composite fiber, the dyeing fastness to friction in a dry state and a wet state can be made to be 4th or higher.

  The wiping cloth of the present invention may include other yarns in addition to the core-sheath composite fiber described above. Other yarns include viscose rayon, solvent-spun cellulose fiber, recycled fibers such as cupra and polynosic, natural fibers such as cotton, hemp, silk, wool and bamboo, polyamides such as nylon 6 and nylon 66, polyethylene terephthalate, poly Examples thereof include aromatic polyesters such as butylene terephthalate and polytrimethylene terephthalate, or synthetic fibers such as polyacrylonitrile and polyurethane.

Hereinafter, the present invention will be described in detail by way of examples. In addition, this invention is not limited by these.

(Example 1)
As a biomass polymer, a polylactic acid having a relative viscosity of 1.850, a melting point of 168 ° C., an L-lactic acid unit of 98.8 mol%, and a D-lactic acid unit of 1.2 mol% was used. An aromatic polyester (copolymerized PET) obtained by copolymerizing 8 mol% of isophthalic acid having a melting point of 230 ° C. was used. Each chip was dried under reduced pressure, and then supplied to a concentric core-sheath type composite melt spinning apparatus for melt spinning. The spinning conditions at this time were such that polylactic acid was the core and copolymerized PET was the sheath, and the core-sheath ratio (mass ratio) was core / sheath = 50/50. The spinning temperature was 260 ° C., and the spinning speed was 3050 m / min. By such melt spinning, a core-sheath type composite fiber which is a highly oriented undrawn yarn of 140 dtex48f was obtained.

  Then, using this highly oriented undrawn yarn as a feed yarn, false twisting was performed in the Z direction under conditions of a speed of 100 m / min, a heater temperature of 120 ° C., a draw ratio of 1.38 times, and a false twist number of 2900 times. A twisted yarn was obtained.

Next, using this false twisted yarn for the pile portion and the ground portion, a circular knitted fabric having the structure shown in FIG. 1 was obtained using an LPJ-H33 type double-sided circular knitting machine (needle density 22 gauge) manufactured by Fukuhara Seiki Co., Ltd. Knitting was performed (weight per unit area: 200 g / m ² ).

  Subsequently, the above-mentioned knitted fabric was scoured and relaxed in an aqueous solution containing 5 g / L of soda ash and 1 g / L of a nonionic activator at 80 ° C. for 20 minutes using a liquid dyeing machine. Then, the dyeing | staining process was carried out on condition of 130 degreeC x 30 minutes with the following dyeing | staining prescription. And the dyed knitted fabric is 80 ° C. × 20 minutes in an aqueous solution containing 5 g / L of soda ash, 1 g / L of hydrosulfite, and 1 g / L of a nonionic surfactant (Sunmol FL: manufactured by Nikka Chemical Co., Ltd.). Reduced and washed under conditions. Then, it was dried at 130 ° C. and finished and set at 140 ° C. for 1 minute to obtain a wiping cloth of the present invention.

In addition, when false twisted yarn was extracted from this wiping cloth and the atypical characteristics were measured, the average cross section deformation rate (CS) = 1.71, S _1.5 = 72.5%, S _1.8 = 33.0 %, S _2.0 = 14.9%.

<Dyeing prescription 1>
Disperse dye 3% omf (“Dianix Bule UN-SE (trade name)” manufactured by Dystar Japan Co., Ltd.)
Dispersing leveling agent 0.5 g / L (“Nika Sun Salt SN-130 (trade name)” manufactured by Nikka Chemical Co., Ltd.)
Acetic acid (concentration 48% by mass) 0.2cc / L

(Example 2)
Use false twisted yarn in Example 1 and polyester modified cross section yarn ("Lumiace (trade name)" 73dtex44f) manufactured in Example 1 as the yarn used, and adopt the structure shown in FIG. 2 instead of FIG. Otherwise, the same procedure as in Example 1 was performed to obtain a wiping cloth of the present invention. In the knitting, false twisted yarns were supplied to the yarn feeders F1 and F2 in FIG. 2, and polyester atypical section yarns were supplied to the yarn feeders F3 and F4. In this wiping cloth, the mixing rate of false twisted yarn was 57.8%, and the basis weight was 200 g / m ² .

(Comparative Example 1)
A wiping cloth was obtained in the same manner as in Example 1 except that a false-twisted yarn of 100 dtex48f made of polylactic acid alone was used instead of the false-twisted yarn made of the core-sheath composite fiber. The basis weight of this wiping cloth was 206 g / m ² . In addition, when false twisted yarn was extracted from this wiping cloth and the atypical characteristics were measured, the average cross section deformation rate (CS) = 1.45, S _1.5 = 47.5%, S _1.8 = 2.0. %, S _2.0 = 0.1%.

(Comparative Example 2)
A wiping cloth was obtained in the same manner as in Example 1 except that a false twisted yarn of 100 dtex48f made of PET alone was used instead of the false twisted yarn using the core-sheath type composite fiber. The basis weight of this wiping cloth was 202 g / m ² . In addition, when false twisted yarn was extracted from this wiping cloth and the atypical characteristics were measured, the average cross section deformation rate (CS) = 1.81, S _1.5 = 79.5%, S _1.8 = 45.0 %, S _2.0 = 33.9%.

  The strength retention of the wiping cloths according to the above Examples and Comparative Examples and the dyeing fastness to friction were measured, and the results are shown in Table 1. In the table, “dry” means the result of the dry test, and “wet” means the result of the wet test.

  As is clear from Table 1, the wiping cloth according to Examples 1 and 2 uses a core-sheath type composite fiber in which polylactic acid is arranged in the core part and copolymerized PET is arranged in the sheath part. In addition, the dyeing fastness to friction satisfied a predetermined range and was excellent in practicality.

  On the other hand, since the comparative example 1 wiping cloth used the fiber which consists of polylactic acid alone, it became a result inferior to heat-and-moisture resistance and dry heat resistance. Further, the fastness to dyeing against friction in a dry state was as low as about 1st grade. Moreover, since the wiping cloth according to Comparative Example 2 uses a fiber made of PET alone, it satisfies the structural requirement that the strength retention is 80% or more and the dyeing fastness to friction is grade 4 or more. However, since the biomass polymer is not contained in the fiber, the main effect of the present invention to reduce the amount of carbon dioxide generated from the production to the disposal stage is not achieved.

  From the above results, it was proved that the wiping cloth of the present invention was extremely excellent in terms of strength retention and dyeing fastness, and in terms of environmental load reduction.

It is an example of the knitted fabric structure | tissue which can be employ | adopted in the wiping cloth of this invention. It is another example of the knitted fabric structure | tissue which can be employ | adopted in the wiping cloth of this invention.

Explanation of symbols

F1 to F4 Yarn feeder C Cylinder needle D Dial needle

Claims (5)

  Using a core-sheath type composite fiber having a core part made of biomass polymer and a sheath part made of a petroleum polymer, the core-sheath type composite fiber has a strong retention rate after being treated in a 50 ° C. × 95% RH environment for 500 hours. A wiping cloth having a dyeing fastness to friction of 4 or more and 85% or more.   The wiping cloth according to claim 1, wherein the petroleum-based polymer is polyethylene terephthalate.   2. The wiping cloth according to claim 1, wherein the petroleum-based polymer is polyethylene terephthalate obtained by copolymerizing at least one component of isophthalic acid, cyclohexanedimethanol and cyclohexanedicarboxylic acid in an amount of 5 to 20 mol%.   The wiping cloth according to any one of claims 1 to 3, wherein the biomass polymer is polylactic acid. The wiping cloth according to any one of claims 1 to 4, wherein the core-sheath composite fiber is a modified cross-section yarn satisfying the following formulas (1) to (3).