JP4344020B2 - Red towel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a crepe towel that is excellent in biodegradability using polylactic acid fibers.
[0002]
[Prior art]
Traditionally, natural fibers such as cotton, hemp, silk, etc. have been used for red towels. In recent years, synthetic fiber products such as nylon, polypropylene, and vinylidene chloride have been developed.
[0003]
Conventional towels made of natural fibers such as cotton, hemp, silk, etc. have poor durability and become hard to use for a long period of time, become dark or yellowish, and have mold during use. it may or generated, or strength or cause breakage tends to decrease, poor practical usability. On the other hand, towels made of synthetic fibers such as nylon, polypropylene, and vinylidene chloride have improved durability, but have a poor feeling of use, and have inherent problems such as changes in quality such as yellowing and darkening. In particular, rough the hardness of synthetic fiber tight irritating to the skin, it may also cause skin disorders such mill scale disease. Furthermore, the environmental impact of waste materials that have been attracting attention in recent years cannot be ignored.
[0004]
Akasuri towel made of synthetic fibers, much more than those using natural fibers in terms of the cost of the point and the supply, less expensive, but has become possible stable supply, with respect to disposal after use almost There are difficulties not found in conventional natural fibers, such as not permanently degrading. In other words , it does not decompose in normal disposal and remains semipermanently, and when incinerated, it generates a large amount of combustion heat and damages the incinerator, or NO _x , SO in the exhaust gas. It increases the amount of _X, or may be carcinogenic to generate dioxin there.
[0005]
[Problems to be solved by the invention]
Or the present invention have a stability of stable quality and supply, also excellent in use feeling has creaking feeling, and at the time of disposal in soil or activated sludge, degrade in a relatively short time at compost , or does not generate toxic gases during incineration, also aims to propose a friendly Akasuri towel environment that minimized the occurrence of harmful NO _X and SO _X due to the low combustion heat to the cellulose parallel.
[0006]
[Means for Solving the Problems]
The present invention uses at least 50% by weight of 20-100d monofilament or single yarn denier 3-25d multifilament made of polylactic acid fiber having an optical purity of 96% or more for warp, and polylactic acid having an optical purity of 96% or more for weft. A multi-filament processed yarn of 75 to 500d made of fibers is used at least 50% by weight, and a polylactic acid filament fiber having a fine fineness and a polylactic acid filament fiber having a fine fineness are mixed in the whole filament fiber of the polylactic acid. It is a red towel towel constructed and used . A red towel is a towel that is mainly used for red dust in the bathroom.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
The optical purity (hereinafter abbreviated as OP) of the polylactic acid used in the present invention is usually 96% or more , particularly preferably 98% or more. If the OP does not reach 90%, the polymer crystallinity is low and the crystallization rate is low, so that yarn breakage is likely to occur during fiber production, and the operability is lowered and the crystallinity of the obtained fiber is also reduced. In addition , there are problems in the manufacturing process and problems during use, such as low fiber strength, lack of thermal stability, and changes in dyeability. In addition, there are problems such as poor heat setability when making knit / denit, which is essential for towel fabric production, making it impossible to produce good crimp yarns, or bulky yarns such as wooly processed yarns. . When the OP is 90% or more, the crystallinity is good and the above problems are few. In particular, when the OP is 98% or more, the fiber crystallinity is particularly excellent, there are few problems at the time of fiber production, and the strength and heat resistance of the obtained fiber and the setting property in knit / denit are very good.
[0008]
In general, polylactic acid is a polymer (a copolymer in a broad sense) in which L-form and D-form lactic acid that are optical isomers are mixed, and the optical purity of polylactic acid is determined by their ratio. The body of living organisms in the natural world is almost composed of L-form compounds, and thus there are abundant enzymes that decompose polymers and compounds composed of L-forms. However, the D-form hardly exists in nature, and polymers and compounds containing a large amount of D-form are not easily decomposed in nature. Therefore, the polylactic acid fiber of the present invention is preferably poly L-lactic acid having a high L-lactic acid content.
[0009]
Therefore, in the composition of polylactic acid fiber, biodegradability decreases as the ratio of D-form increases. In this sense, OP is preferably high.
[0010]
Polylactic acid fibers, polylactic acid prepared by melt spinning or solution spinning, but the diversity of melt spinning production efficiency and product, preferably In terms of load on the environment in the production is small.
[0011]
In melt spinning, polylactic acid resin is heated and melted to a melting point or higher, and discharged and cooled in the air from a spinneret having minute holes to obtain fibers. The discharged / cooled fiber is wound to go to the next step. However, in the case of long fibers, the winding speed is called a conventional spinning method called POY (Partially Oriented Yarn). ) Method with a winding speed of about 5500 m / min or less, called a HOY (Highly Oriented Yarn) method, or a method with a winding speed of about 5500 m / min or more, or SPD (Spin Draw) ) Method can be adopted. Further, the short fibers, to push a number of nozzles overwhelmingly as compared with the long fiber, the winding speed is normal to slower than long fibers, it is carried out at usually 2000 m / min or less. In particular, it is most commonly performed at 1500 m / min or less.
[0012]
In the red towel of the present invention, at least 50% by weight of polylactic acid filament fiber is used for each of the warp and weft of the fabric. Akasuri towels other components (hereinafter referred to as "non-polylactic acid fiber component") may be a conventional synthetic fiber, or may be a natural fiber. Preferably, a majority of the non-polylactic acid fiber components are natural fibers, more preferably 2/3 or more are natural fibers, and particularly preferably all are natural fibers. When the polylactic acid fiber is less than 50% of the towel, the durability and the feeling of use are not improved, or the biodegradability is poor.
[0013]
The filament fiber of polylactic acid used in the present invention is any fiber such as a normal cross section fiber, a flat cross section fiber, a Δ cross section fiber, a hollow cross section fiber (◯, Δ), a non-circular cross section fiber such as a U-shaped cross section fiber, etc. Cross sections can also be used. In consideration of the feeling of use and the like, it is also possible to use a mixture of a flat cross-section fiber, a Δ cross-section fiber, or a modified cross-section fiber such as a U cross-section fiber, rather than a simple ○ cross-section fiber. In order to improve the texture, swellness, detergency, foaming properties, etc., the irregular cross-section fibers are mixed at about 10% or more, preferably 20% or more, more preferably 30% or more. In the case of mixing, a mixed fiber method may be used, but it may be used as a warp or weft of a woven fabric or a part thereof.
[0014]
The thickness of the filament fiber of polylactic acid is usually a monofilament of single yarn denier 20 to 100d or a multifilament of single yarn denier 3 to 25d , more preferably a monofilament of 25 to 75d or single yarn denier 4 to 20d. Multifilament. Whether to use a monofilament or a multifilament can be determined according to the application and target performance. In the multifilament, untwisted yarn, sweet twisted yarn or medium twisted yarn can be used, but it is preferable to use untwisted yarn in terms of cost.
[0015]
Filament fibers of polylactic acid for use in Akasuri towel weft of the present invention, multifilament usually 75～500D, preferably multifilament 100～400D. Single yarn denier is usually 3 to 15 d, but can be used depending on the purpose and application outside this range. Because wefts have an important role in the cleaning effect of the towel and the touch, crimped yarn by knit / denit method, crimped yarn by staffin method, crimped yarn by gear method, or crimped yarn by Panlon method It is preferable to use a machine-crimped yarn such as, a spiral-shaped crimped yarn by side-by-side composite yarn, or a processed yarn such as false twisted yarn, among others, false twisted yarn called Woolley yarn or the like, or yarn knit Denit is especially preferred. Fibers may be of one type, texture and feel, can be mixed using several kinds of fibers for improved durability. In particular, if a mixed Tsukai of fibers with fibers and thin fineness having a thick fineness, feeling also durability is improved. In the combination of these fibers, the yarn itself becomes swollen by changing the difference in fineness and the shrinkage rate (for example, heat shrinkage rate) of each fiber, and the fluffy texture and soft feeling of use it is possible to produce, more preferable. In particular, when the shrinkage rate of the fine yarn is large and the shrinkage rate of the fine yarn is set low, this effect can be exhibited more remarkably.
[0016]
As long as at least 50% by weight of polylactic acid filament fiber is used for each of the warp and the weft, a polylactic acid staple fiber may be further used. In that case, the polylactic acid fiber of 100% of the spun yarn can be well as other fibers, such as cotton, hemp, natural fibers, nylon, such as silk, polyester, also be used in blend the acrylic fiber. However, from the viewpoint of environmental load, it is preferable to use natural fibers as the blended partner. In addition , a richer texture, feeling of use, durability, and the like can be expressed by using a mixture of different polylactic acid staple fibers having different finenesses and fibers having different hot water shrinkage rates.
[0017]
As described above, the cast towel of the present invention can use polylactic acid fiber or a mixed spun yarn of polylactic acid fiber and other fibers, and further woven other synthetic fibers or natural fibers into these fibers. It is possible to develop a weaving pattern and a different color at the time of dyeing.
[0018]
If the structure | tissue of a textile fabric is a woven structure normally used for toweling, it will not specifically limit. For example, ordinary plain weave, twill weave, and satin weave are basically used, and those having a changed structure can also be used. Moreover, although it is a single woven fabric of a normal weave, a double woven fabric is also possible in order to give a high-class feeling. In particular, in the case of interweaving with other fibers, it is preferable to use a structure other than plain weave in order to change the type of yarn to be put on the surface according to the characteristics of the fibers. For example, when softer fibers are used for the wefts, it is preferable to have a structure in which a lot of wefts are produced by twill weave or satin weave when soft texture is given.
[0019]
The density of the woven fabric is usually 3-50 yarns / inch, preferably 5-40 yarns / inch, and more preferably 10-30 yarns / inch. The weft is usually 15 to 50 yarns / inch, preferably 18 to 45 yarns / inch, and more preferably 20 to 40 yarns / inch.
[0020]
With 100% polylactic acid fiber, dyeing can be performed with a disperse dye at a temperature of 95 to 120 ° C., but polylactic acid fiber has a slightly lower dyeing fastness than conventional polyester fiber. However, the dye fastness can be maintained by appropriately selecting the dye. For example, those having medium hardness (SF to F type) are preferable. The dyeing concentration can be appropriately selected depending on the use and purpose. Also, mixed weave with other fibers, in Akasuri towel blend Tsukai, when dyeing the other fiber 2 bath dyeing or other fiber dyes can also be dyed by one bath dyeing added simultaneously. It is also possible to process ultraviolet absorbers, slip agents, antibacterial agents, etc. during or after dyeing. In particular, in order to improve light fastness, it is preferable to use an ultraviolet absorber of 1% / owf or more.
[0021]
The scraped towel of the present invention is excellent in biodegradability when discarded after use, and in the case of incineration treatment, the combustion heat is 3400-3500 cal / g, which is similar to that of newspaper, so the furnace is damaged or NO _X and that no to generate toxic gases such as gases and dioxins sO _X or the like can be easily incinerated. Because it is biodegradable, or buried in a corner of the home garden, or treated with compost machine for home use, it is possible to easily composting in the region of the compost factory. In this respect, the red towel of the present invention can be said to be a very environmentally friendly material.
[0022]
【Example】
The present invention will be specifically described below with reference to examples. In the examples, “part” means “part by weight” unless otherwise specified, and “%” means “% by weight” unless otherwise specified. Relative viscosity: ηrel was determined by a conventional method at 20 ° C. in a mixed solvent of phenol / tetrachloroethane = 6/4 (weight ratio). The melting point (Tm) was determined from the peak value of the endothermic peak of a differential scanning calorimeter (hereinafter referred to as DSC) manufactured by Rigaku Corporation.
[0023]
Example 1
A polylactic acid having an L-lactic acid content of 99.2%, ηrel = 3.1, a weight average molecular weight of 130,000, a melting point of 175 ° C. was melted at a melting temperature of 230 ° C., a pore diameter of 0.25 mm, and the number of pores It was extruded into the air from a spinning nozzle having 48 pieces and spun by a normal filament method to obtain a 75d / 24f bifilament filament. Similarly, a single filament was used to obtain a filament of 400d / 48f. Each strength 4.5g / d, 4.2g / d, elongation 34%, 37%, had physical properties of modulus ^{685Kg / mm 2, 645Kg / mm} 2. The 75d / 24f yarn is used as a warp with a torque of 300 T / m. The 400d / 48f yarn is heat-treated at 110 ° C. for 40 minutes and then knitted to be crimped and used as weft. Using the fibers, weft weft fabrics were manufactured with warp yarns appearing on the surface with a warp: 10 / inch and weft: 35 yarn / inch yarn design. Performance as Akasuri towel fabric material is very soft friction with the skin, it was excellent and foaming soap. Moreover, the drainability after use was also good, and it was possible to dry well indoors.
[0024]
Example 2
A polylactic acid having an L-lactic acid content of 99.1%, ηrel = 3.3, a weight average molecular weight of 150,000, and a melting point of 173 ° C. was melted at a melting temperature of 235 ° C. It was extruded into the air from a spinning nozzle having 12 pieces and spun by a normal filament system to obtain a 30d / 1f monofilament for 12-minute fiber separation. A filament of 400 d / 24 f was obtained in the same manner as in Example 1. Each strength 4.0g / d, 4.3g / d, elongation 38%, 36%, had physical properties of modulus ^{617Kg / mm 2, 640Kg / mm} 2. The 30d / 1f monofilament is used as it is as a warp. 400d / 24f uses weft containing the false twist about 1500T / m at texturing machine of a spindle type as one of the ten weft Example 1. Using this fiber, a plain fabric was manufactured with a design of warp: 10 / inch and weft: 35 / inch. Performance as Akasuri towel fabric was very soft, and the friction of the skin is excellent in lightweight feeling was very soft. The soap foaming was also good. Moreover, the drainability after use was also good, and it was possible to dry well indoors.
[0025]
Example 3
Using the polylactic acid of Example 1, it was extruded into the air at an extrusion temperature of 220 ° C., and 1.5d (38 mm cut) staples were obtained by a normal production method. A 20/1 yarn is obtained with the fiber, and this is used as one of the five wefts of Example 1. The spun yarn had a strength of 750 g and an elongation of 30%. 30d / 1f manufactured in Example 2 was used as a warp, and a warp fabric was manufactured with a design of warp: 10 / inch and weft: 30 / inch. Performance as Akasuri towel fabric was very soft, and friction between the skin and excellent in lightness and loft was very soft. The soap foaming was also good. Moreover, the drainability after use was also good, and it was possible to dry well indoors.
[0026]
Example 4
The polylactic acid staple of Example 3 / about 1.3 d cotton was mixed at a ratio of 75/25 to obtain 15/1 yarn. Using this as the weft, a woven fabric having the same structure as in Example 3 was obtained. Performance as Akasuri towel fabric was very soft, and the friction of the skin is excellent in lightweight feeling was very soft. The soap foaming was also good. Moreover, the drainability after use was also good, and it was possible to dry well indoors.
[0027]
Example 5
Melted at 225 ° C. melt temperature using a polylactic acid of Example 1, extruded in the air from the nozzles 96 pairs consisting of small holes 5 Ke having a pore size of 0.12 mm, small holes 5 Ke having ties U section 150d / 96f A filament of (single yarn 1.56d) was obtained. The fiber had physical properties of strength 4.5 g / d, elongation 35%, and elastic modulus 658 kg / mm ² . Two of the fibers were combined and false twisted with a spindle type false twister. The false twisted yarn and the 400d / 24f knit / denit yarn of Example 2 are used as wefts in a ratio of 2/8 . As the warp , a plain woven fabric was manufactured with a design of 10 yarns / inch alternately of 300d / 192f processed yarn and 400d / 24f knitted / denit yarn and 30 weft / inch yarn. Performance as Akasuri towel fabric was very soft, and the friction with the skin has excellent lightness was very soft. The soap foaming was also good. Moreover , the drainability after use was also good, and it was able to dry sufficiently indoors.
[0028]
【The invention's effect】
The clam towel made of the polylactic acid fiber of the present invention has an excellent feeling of use and is decomposed by landfill treatment in the disposal process after use, and finally decomposes into water and carbon dioxide gas. Without causing excessive heat generation at the time of incineration, NO _X effects on incinerators and combustion gas, it is possible to reduce the generation amount of hazardous gases such as SO _X, it can be said that a very environmentally friendly Akasuri towel . As the characteristics of Akasuri towels made of polylactic acid fibers, slightly hydrolysed becomes weakly acidic, or the like can create a gentle conditions in skin, and healthy preferred products also environmentally.

Claims (1)

At least 50% by weight of 20-100d monofilament made of polylactic acid fiber with an optical purity of 96% or more is used for the warp or multifilament of single yarn denier 3-25d is used, and the weft is made of polylactic acid fiber with an optical purity of 96% or more. ˜500 d multifilament processed yarn is used at least 50% by weight, and the polylactic acid filament fiber is mixed with a polylactic acid filament fiber having a thick fineness and a polylactic acid filament fiber having a fine fineness. A warm red towel.