JP2002165721A - Biodegradable bathing towel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bathing towel having excellent cleaning ability to remove the dirt on a skin, softness to the skin and a property to naturally decompose, and not giving a load on environment on dumping. SOLUTION: The bathing towel is made of a warp knitted fabric formed by a yarn made of a biodegradable fiber. 50-100 mass % of the yarn made of the biodegradable fiber is a multifilament yarn made of a polylactic acid fiber. The multifilament yarn made of the polylactic acid fiber is a nonturning or weakly turning yarn having a crimped shape in the longitudinal direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bath towel excellent in disposability, which can be suitably used with a soft touch to slime and the like, and which can be biodegraded by compost after use.

[0002]

2. Description of the Related Art Conventionally, bath towels are roughly classified into a soft type using a spun yarn mainly composed of cotton yarn and a hard type using a synthetic fiber long fiber such as nylon. Each is widely used.
Of the above, the soft type has the advantage that the feel when washing the body is soft and it is hard to hurt the skin, but the friction with the skin is too small, it is difficult to remove fine dirt clogged in pores, etc., It is uneconomical to consume a large amount of a cleaning agent such as soap in order to sufficiently foam. On the other hand, the hard type is easy to remove dirt from the skin, consumes less detergent, and has excellent durability, but the rigidity of the synthetic fiber used is too irritating to the skin,
It is avoided by people and women with sensitive skin, and because the material itself does not decompose naturally, generates a large amount of heat during combustion and easily generates harmful gases, which poses a problem of environmental load due to disposal.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the conventional bath towels, and has excellent detergency for removing skin stains, is gentle on the skin, and decomposes naturally. It is an object of the present invention to provide a bath towel which has no environmental impact when disposed.

[0004]

Means for Solving the Problems The present inventors have studied using various biodegradable fibers in order to solve the above-mentioned problems.
In order to prevent skew deformation when the knitted fabric is formed, it is necessary to apply a crimp having a small swirling property in the longitudinal direction of the yarn, and polylactic acid is suitable as a material subjected to knitting / denitting for that purpose. Further, by using such a polylactic acid multifilament yarn having a crimp for a warp knitted fabric, an elastic undulating surface is created on the surface, and a toweling fabric that gives a suitable stimulation to the skin is obtained. And found that the present invention was completed.

That is, the gist of the present invention is as follows. 1. What is claimed is: 1. A bath towel using a warp knitted fabric formed of a yarn composed of biodegradable fibers, wherein 50 to 100% by mass of the yarn composed of the biodegradable fibers is composed of a polylactic acid fiber. A bath towel, wherein the multifilament yarn comprising the polylactic acid fiber is a non-swirling or weakly swirling yarn having a crimp shape in a longitudinal direction. 2. The above-mentioned bath towel, wherein the multifilament yarn composed of polylactic acid fiber has a boiling water shrinkage of 3% or less. 3. 3. The bath towel according to the above 1 or 2, wherein the multifilament yarn made of polylactic acid is provided with a crimp shape in a longitudinal direction by knitting / denitting.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. From the viewpoint of disposal after use, the bath towel of the present invention needs to be formed using a thread composed of biodegradable fibers (hereinafter, sometimes abbreviated as biodegradable thread).
As the biodegradable fibers, natural fibers such as cotton, cellulosic fibers such as rayon, and biodegradable thermoplastic resin fibers such as polylactic acid can be used. As the biodegradable thermoplastic resin, an aliphatic polyester resin which is biodegradable through hydrolysis is preferable, and among them, an aliphatic polymer synthesized from a diol component and a dicarboxylic acid component is particularly suitable, and polylactic acid is preferable. , Polyalkylene alkanoates, poly β-hydroxy alkanoates and copolymers thereof, and specifically, polylactic acid is most preferably used.

The bath towel of the present invention comprises a warp knitted fabric, and the biodegradable yarn forming the warp knitted fabric includes a multifilament yarn made of polylactic acid fiber. Need to have a crimped shape in the longitudinal direction and be non-swirlable or weakly swivelable. Since the yarn has a crimped shape in the longitudinal direction, an elastic undulating surface is formed on the surface of the warp knitted fabric formed using the yarn, thereby realizing a detergency for removing stains on the skin. Also,
Since the yarn is non-swirl or weakly swirlable, the warp knitted fabric formed by using the yarn does not undergo skew deformation. In addition, the non-swirl property or the weak-swirl property in the present invention is defined as follows. That is, as shown in FIG. 1, a yarn 1 having a length of about 1 meter is folded into two to form a loop 1 having a closed end, and a weight 2 having a predetermined mass (the number of decitex of yarn × 0.1 g) is hooked on the loop. It is suspended naturally, and the number of twists per 50 cm generated at this time (the number of twists is 2 in FIG. 1) is defined as the turning index.
Those having a turning index of 0 are referred to as non-turning properties, and those having a turning index of 1 to 15 are referred to as weak turning properties. In a warp knitted fabric formed using a revolving yarn having a revolving index of more than 15, the shape is easily damaged due to skew deformation, and the handleability as a bath towel is deteriorated. Preference is given to using non-spinning yarns.

The filament cross section of the multifilament yarn made of polylactic acid or other biodegradable fibers is not particularly limited, and may be any cross section such as a round cross section, a multilobal cross section, a flat cross section, and a hollow cross section. It may be in shape,
A plurality of types having different cross-sectional shapes may be mixed.

In the present invention, it is particularly important that the multifilament yarn having a crimp shape in the longitudinal direction and having a non-swirling property or a weakly swirling property is made of polylactic acid fiber. Non-swirl crimps are obtained by knit / denit processing described later, but depending on the type of fiber, crimp does not occur even if such processing is performed,
This is because even if crimp occurs, the crimp often disappears easily due to external force or the like, and processing cannot be performed due to a low melting point. The present inventors have studied various fibers and found that polylactic acid fibers having a melting point of 120 ° C. or higher impart a continuous non-swirl crimp by knit / denit processing among biodegradable fibers. It was found to be the most suitable fiber to make. Another reason for using polylactic acid fibers is the moderate rigidity of polylactic acid. In other words, by using polylactic acid, the elastic undulating surface formed on the warp knitted fabric surface has a detergency to remove dirt on the skin, and may cause excessive skin irritation and pain. Instead, it gives a pleasant massage effect.

[0010] The boiling shrinkage of the multifilament yarn comprising the polylactic acid fiber is preferably 3% or less, more preferably 2% or less. When the bath towel of the present invention is used in a bath, it may be immersed in hot water. However, if the boiling water shrinkage exceeds 3%, the yarn shrinks due to the action of hot water and warp knitting. The voids between the ground loops and between the filaments may be lost, and the foaming property when foaming soap or the like with a bath towel tends to deteriorate, which is not preferable.

The proportion of the multifilament yarn comprising polylactic acid fibers in the biodegradable yarn forming the bath towel of the present invention must be 50 to 100% by mass. , 75 to 100% by mass. If the above ratio is less than 50%, the effect of using the yarn cannot be obtained. In addition, the performance such as usability and the biodegradability can be changed by mixing other biodegradable yarns other than the multifilament yarns composed of the polylactic acid fibers. For example, non-crimped flat yarn, side-by-side conjugate yarn, interlaced entangled yarn, or cotton,
By using a spun yarn such as rayon as another biodegradable yarn, it is possible to change practical performance such as feel, foaming property, and detergency.

Although the polylactic acid fiber used in the present invention has biodegradability, it has the property of being hydrolyzed because it is a kind of polyester. Is characterized by the fact that biodegradation by microorganisms is accelerated after the process has progressed, and ultimately changes to water and carbon dioxide. That is, the biodegradation is performed efficiently by promoting the hydrolysis preferably in an environment of a temperature of 55 ° C. or more and a humidity of 65% or more. Therefore, the bath towel of the present invention containing 50% by mass or more of the polylactic acid fiber is placed in a high-temperature and high-humidity environment, so that hydrolysis of polylactic acid starts, and after a certain period of time, biodegradation by microorganisms occurs with time. Proceed to. When biodegradation is performed, it may be left in a compost or soil where bacteria and the like proliferate. However, by using a composting machine capable of setting the temperature and humidity, efficient processing can be performed.

Next, a preferred method for producing the bath towel of the present invention will be described. First, in order to obtain a multifilament yarn which is made of polylactic acid fiber, has a crimp shape in the longitudinal direction, and is non-rotating, knitting and denitting are performed. That is, a drawn yarn of a multifilament yarn made of polylactic acid fiber is continuously knitted into a tubular shape, and this tubular knitted fabric is treated with hot water at about 100 ° C., dried, and then deknitted. Thereby, a non-swirl crimp is obtained as a yarn formed in the longitudinal direction (hereinafter, abbreviated as a knit / denit processing yarn). At this time, knit
In order to reduce the boiling water shrinkage of the denitted yarn to 3% or less, it is preferable to increase the shrinkage during hot water treatment by increasing the knitting density when knitting into a tubular shape.

Next, a warp knitted fabric is knitted by a known method using the knitted / denitized yarn and, if necessary, other yarns, and the knitted fabric is appropriately sewn to obtain a bath towel according to the present invention. Is obtained. In addition, as a method of dyeing the bath towel of the present invention, in the case of using 100% of polylactic acid fiber, it can be dyed at a temperature of 90 to 110 ° C. using a disperse dye and contains other biodegradable fibers. In such a case, one or more baths may be dyed using a dye suitable for the fiber.

[0015]

Next, the present invention will be described specifically with reference to examples. Example 1 Polylactic acid containing 99.3% of poly-L lactic acid (melting point: 17
(2 ° C, average molecular weight 140,000) by melt spinning using a conventional method,
Subsequently, a multifilament yarn (560 dtex / 96 filaments) made of polylactic acid was obtained by performing a drawing process. Using this multifilament yarn, a tube knitting machine (cylinder diameter 10.16 cm, number of needles 1
20) to form a continuous tubular knitted fabric. Then
This knitted fabric was subjected to hot water treatment in 95 ° C. hot water for 30 minutes, dried, and then subjected to deknitting and winding to obtain a knitted / denitized yarn having a boiling water shrinkage of 1.2%. Using the above-mentioned knitted / denitized yarn, a net-shaped warp knitted fabric (25 cm width) is produced by combining a chain knitting and an inlay knitting with an 8-gauge two-sheet reed Russell knitting machine, and this is 50c.
After being cut to length m, the longitudinal end was sewn to produce the bath towel of the present invention. When the bath towel of the present invention obtained as described above was used, creamy and abundant lathering was obtained even with a small amount of soap or body shampoo, and a moderate slip between the skin and the skin was obtained. There was a feeling and it was comfortable, and it was also excellent in slime effect. In addition, it was used for one month for bathing, but it was used comfortably without any particular decrease in performance. Then, the one used for one month is used in a composting machine using soil bacteria (set temperature 58
(C °, set humidity 70%), 90% disappeared in about 10 days.

[0016]

The bath towel of the present invention has a moderately elastic undulating surface, so that it has excellent detergency for removing dirt on the skin, but has a comfortable sliding feeling and does not excessively irritate the skin. It is a highly practical bath towel that can provide abundant creamy foaming by using a small amount of soap or the like. Furthermore, when discarded after the end of its useful life, it is decomposed into harmless substances in the soil or in a composting machine in a short time, or generates little harmful gas even when incinerated. Therefore, the burden on the environment is extremely small. Further, according to the production method of the present invention, such a bath towel can be easily produced.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a method for checking the presence or absence of a turning property of a yarn used in the present invention.

[Explanation of symbols]

 1. 1. Loop of thread Weight 3. hook

Claims (3)

[Claims] 1. A bath towel using a warp knitted fabric formed of a thread composed of biodegradable fibers, wherein 50 to 100% by mass of the thread composed of the biodegradable fiber is polylactic acid. A bath towel, which is a multifilament yarn made of fibers, wherein the multifilament yarn made of the polylactic acid fiber is a non-swirling or weakly turning yarn having a crimp shape in a longitudinal direction. 2. A bath towel characterized in that a multifilament yarn made of polylactic acid fiber has a boiling water shrinkage of 3% or less. 3. The bath towel according to claim 1, wherein the multifilament yarn made of polylactic acid is provided with a crimp shape in a longitudinal direction by knit / denit processing.