JPH0284560A - Hot-melt short fiber containing allantoin compound and production thereof - Google Patents

Abstract

PURPOSE:To obtain the subject fiber having flame-resisting effect and excellent carding performance of short fiber and suitable as a diaper in the form of a nonwoven fabric by depositing an allantoin compound on the surface of a fiber. CONSTITUTION:The objective short fiber can be produced by passing (A) a spun and crimped fiber of a polyolefin polymer (e.g., low-density polyethylene) into (B) a solution of an allantoin compound to fix 0.1-10wt.% of the component B to the component A and subjecting the fiber to subsequent processes such as cutting.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a fiber made of a polyolefin polymer on which an allantoin compound having cell activation and wound protection effects is deposited, and a method for producing the same. It is.

(Prior art) Allantoin compounds have long been used as cell activators and wound protectants, but also as skin anti-inflammatory agents. Utilizing this property, they have been widely used in pharmaceuticals, cosmetics, daily necessities, etc. It is something that exists.

Recently, a new use of the above-mentioned allantoin compound is the application to "allantoin-added paper for diaper dermatitis" [Pediatric Clinical J vol. 30. Nc7P15
3 (1977).

The allantoin-added paper is a sheet material made of rayon and cellulose nonwoven fabric to which an allantoin compound is added. The inventors have already filed a patent application in 1986-1.
No. 12997 proposes an allantoin compound-containing nonwoven fabric in which solid particles of an allantoin compound are thermally fixed to the surface layer of a polyolefin polymer, and a method for producing the same.

(Problems to be Solved by the Invention) Here, the following three methods have been proposed for applying a drug using fibers as a support during the process of forming a nonwoven fabric.

■A method of applying a chemical in the form of an aqueous solution or aqueous dispersion to fibers by spraying, impregnating, coating, etc. ■A method of thermally fixing a chemical to the fiber surface ■A method of wet paper making by dispersing the chemical in water together with a binder. In the yarn manufacturing process, if you try to apply method (1), the chemical will fall off from the guide etc. because the chemical is applied during the spinning and drawing process of the heat-adhesive short fibers, and the problem will occur. This is not preferred because it inhibits stretchability.

When attempting to apply method (2), it is necessary to heat-fix the material to prevent it from mechanically falling off even if the drug is applied. However, if thermal fixation is performed, the card passageability of the non-woven fabric will be hindered.

In the wet papermaking method (2), there are problems such as the chemicals being hidden by the binder and falling off due to external forces, etc. when being rubbed during use. Furthermore, since the binder is used in areas that come into direct contact with the human body, it is necessary to select a binder from the viewpoint of safety.

It cannot be added at the fiber manufacturing stage.

As mentioned above, although the application of chemicals has been studied, there is still no solution for a thermally adhesive short fiber for nonwoven fabrics that is economical, and that reduces allantoin elution due to physical friction and urination, etc., and its manufacturing method. The current situation is that this has not been done.

(Means for Solving the Problems) The present inventors have conducted intensive studies to solve the above problems.
This has led to the present invention.

Namely, the gist of the present invention is to provide an allantoin compound-containing heat-adhesive short fiber in which an allantoin compound is deposited on the fiber surface on which a polyolefin polymer is partially or fully exposed, and a method for producing the same. It is something.

Examples of the fibers used in the present invention include fibers made of polyolefin polymers and fibers in which polyolefin polymers are exposed on part or all of the fiber surface;
Possible examples include core-sheath type composite fibers, eccentric core-sheath type composite fibers, and island-in-the-sea type composite fibers. Among the above-mentioned composite fibers, care must be taken during fiber production, especially in the case of bonded composite fibers, it is necessary that both components do not separate during the spinning process and the cut-tS shrinking process.

Next, the polyolefin polymers constituting the heat-adhesive short fibers include low-density polyethylene, high-density polyethylene, linear low-density polyethylene copolymerized with α-olefin hydrocarbon, crystalline polypropylene, and copolymerized polyethylene. Examples include polymers.

In the case of composite fibers, at least one component is a polyolefin polymer, and other components include polyester,
Thermoplastic polymers such as polyamide and polypropylene are preferred. Composite fibers can be formed by using a plurality of commonly used extruder type extruders and merging two component polymers in a nozzle pack or near a nozzle plate to form a composite fiber.

The composite ratio of composite fibers can be adjusted freely depending on the use and purpose, as long as it satisfies the various performances required for practical use, such as bulkiness, strength, elongation, and texture. You can choose.

Allantoin compounds used in the present invention include allantoin (melting point 245°C), chlorohydroxyaluminum allantoinate (melting point 245°C), and dihydroxyaluminum allantoinate (melting point 248°C).

Here, the melting point was measured using a PerkinElmer differential scanning calorimeter DSC-2C under a nitrogen atmosphere at a heating rate of 2.
It was determined from the peak temperature of the DSC curve measured under the conditions of 0°C/min and a sample amount of 5 mg. The three types of allantoin compounds mentioned above are all thermally unstable compounds that decompose near their melting points. Therefore, in order to uniformly deposit the compounds on the fiber surface, they must be applied in a solution state. Furthermore, it is necessary to maintain a drying temperature at which the fibers do not fuse together until they pass through a card machine.

In particular, since the above fiber contains polyolefin, 1
It is desirable to dry at 00°C or lower.

The amount of the allantoin compound fixed to the heat-adhesive short fibers is not particularly limited, but is preferably 0.1-10% by weight.

If the amount is less than 0.1% by weight, the cell activation effect and wound protection effect will be poor, while if it exceeds 10% by weight, the cost will be higher, but there is not much difference in terms of the above-mentioned cell activation effect, etc. It is from.

In the present invention, in order to produce heat-adhesive staple fibers in which an allantoin compound is deposited on the fiber surface on which a polyolefin polymer is partially or completely exposed, the allantoin compound is added after the crimping process. It is necessary to grant

As for this application method, it is also possible to apply the allantoin compound alone in a solution state. usually.

In the short fiber manufacturing process, especially when a polyolefin polymer, which is a low melting point polymer as in the present invention, is exposed, the fibers are cooled with water or the like to prevent the fibers from fusing together. Therefore, it is preferable to apply the allantoin compound in a step after this crimping process.

Note that since the oil applied in the spinning/drawing process usually flows out in the cooling process after the crimping process, the oil is applied after this cooling process. therefore.

From the viewpoint of process rationalization, an allantoin compound may be dissolved in the oil and added at the time of applying the oil. Also.

For the purpose of improving sustained release during urination, a water-soluble polymer may be dissolved in a system of an allantoin compound and an oil agent, and a solution consisting of a tertiary system may be applied. in this way.

The application method and prescription may be selected as appropriate.

Rather than applying allantoin compound as a single solution,
When used in combination with an oil agent, smoothness is imparted to the fiber surface,
Card passing efficiency will be improved.

Furthermore, when used in combination with a water-soluble polymer, the binder effect suppresses the outflow of the allantoin compound during urination, providing a sustained release effect. Examples of water-soluble polymers include polyvinyl alcohol, sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose,
Pullulan and the like are preferably used. Note that the amount of the water-soluble polymer attached is not particularly limited, but is preferably 11% by weight or less. If it exceeds 1% by weight, it is not preferable because when the obtained short fibers are applied to a carding machine, card passing properties become poor.

Next, a method for producing heat-adhesive short fibers containing an allantoin compound according to the present invention will be explained with reference to the drawings.

FIG. 1 shows a process diagram in which an undrawn tow is drawn and cut into short fibers through a crimping process. In the present invention, an allantoin compound is added in zone B after the crimping process.

As for the application method, the aqueous solution 1 dispersion can be applied by spraying, roller application, or dipping treatment.

Furthermore, drying after application is carried out at a drying temperature of 100° C. or less without thermal deterioration of the allantoin compound and without fusion between the fibers, and short fibers with allantoin compound deposited can be obtained after the first cutting step.

These steps are 4 (
It is possible to obtain short fibers having an allantoin compound deposited on the fiber surface.

The obtained short fibers can be used alone or mixed with other materials to form a nonwoven fabric by a heat fusion method.

(Function) The present inventors speculate as follows as to the reason why the allantoin compound-containing heat-adhesive short fiber of the present invention has good card passability and the allantoin compound attached to the fiber surface does not flow out due to urination etc. are doing.

Since the allantoin compound is applied in a solution state to the surface portion of the fiber, it is deposited uniformly and thinly on the fiber surface. Therefore, the card passes smoothly through the card machine, has little resistance, and is less likely to fall off. Further, the step of applying 1 is carried out after the crimping step, and smoothness is improved especially when used in combination with an oil agent, and the allantoin compound is dotted in the oil agent film. Due to this oil coating, when used on the top sheet of disposable diapers,
The oil component improves the parent wood performance, improves the wetting performance of the sheet, and allows smooth penetration into water-absorbing substances. Similarly, by using a water-soluble polymer in combination, the allantoin compound is dotted in one resin film, so a sustained release effect of the drug can be obtained, and as another advantage, card passing properties are improved.

By depositing the allantoin compound uniformly in a thin film state on the fiber surface in this manner, short fibers for nonwoven fabrics that have good cart passage properties and are less likely to fall off during urination can be obtained.

(Example) Next, one embodiment of the present invention will be explained with reference to examples.

First, the allantoin compound attached to the fibers or the allantoin compound deposited on the nonwoven fabric was quantified and the performance of the obtained nonwoven fabric was determined by the following method.

(1) Quantification of Allantoin Compound A sample of a certain number of layers was taken, and A1 was quantified by flame analysis to measure the amount of allantoin attached and the amount of allantoin remaining after the dissolution test.

(2) Dissolution test of allantoin compound A predetermined amount (6C1ll x 6CII+) of allantoin compound-deposited nonwoven fabric was sampled and placed in a metal hat filled with physiological saline.
Soaked for minutes. Next, glass plate 2 of 7c+nX7c+n
A dipping-treated allantoin nonwoven fabric is sandwiched between the sheets.
A load of 1.5 kg was applied and left for 5 minutes. after that,
The nonwoven fabric subjected to the dipping treatment and pressure treatment was dried at 100'C. The allantoin compound was quantified in the sample allantoin nonwoven fabric before and after dipping, and the residual amount was determined from the following formula.

(3) Tensile strength of nonwoven fabric The maximum tensile strength was measured from a test piece having a sample width of 30u+ and a length of 100n according to the strip method described in JTS L-1096. Note that the strength in the lateral direction in Table 1 is sampled in the direction perpendicular to the 3rd direction.

(4) Compression bending resistance A nonwoven fabric sample of 5 cm x 10 cm was made into a cylindrical shape, a secondary compression load cell was attached, and the maximum stress when the sample was compressed was determined. A smaller value indicates a softer texture.

Example 1 High-density polyethylene with a melting point of 135'C is used as a sheath component, polyethylene terephthalate with a melting point of 258C is used as a core component, the discharge amount is adjusted so that the weight ratio of the core-sheath component is 50:50, and spinning is performed. Composite spinning was carried out at a speed of 1200 m/min. Next, the obtained undrawn yarn was stretched in a tow state with a total fineness of 200,000 denier at a stretching temperature of 90°C and a stretching ratio of 2.3 times, crimped with a crimper, dried, and cut. Short fibers of 2 denier x 51 long fiber length were obtained. Here, in step B in FIG. 1 after the crimping step, chlorohydroxyaluminum allantoinate is used as the allantoin compound, and an isometric compound of polyethylene glycol (degree of polymerization 400) monolaurate and lauryl sulfate potassium salt is used as the oil component. The above-mentioned allantoin compound was added to an aqueous solution consisting of the following, and polyvinyl alcohol was further applied as a water-soluble polymer by spraying in a solution state. (Amount of oil component deposited: 0.6%) The amount of allantoin compound deposited on the obtained short fibers was measured by flame analysis. The results are shown in Table 1.

Table 1 shows that when the allantoin compound was applied at the experimental position 2, the allantoin compound was applied at position A immediately before crimp formation. However, in the crimping process, external forces and friction between fiber bundles occur when crimping the fibers, so especially in the case of fibers made of low melting point polymers,
To prevent fusion between fibers, the fibers are cooled with water after the first crimping step.

Therefore, this water causes the allantoin compound to flow out. In fact, in Experiment Kan 2, the amount of the allantoin compound attached in the short fiber state was smaller than in other Experiments 3 to 5. From this, it can be seen that the process of applying a finishing oil (position B in FIG. 1) is appropriate.

Example 2 The short fiber cotton obtained in Example 1 was passed through a carding process and opened to form a web, which was then heat treated to form a nonwoven fabric. In this process of making a nonwoven fabric, process observation and performance evaluation of the obtained nonwoven fabric were performed. The results are shown in Table 2.

Table 2 Here, the process observation is the experiment 11kL 1.3~5 raw cotton (
Floor 1 represents a blank with no allantoin deposited. ) was used, and the card passability and the generation of white powder during the carding process were observed.

From the table, the present invention Nα3.4 shows card passing properties and opening properties comparable to blank raw cotton (positive 1) to which no allantoin compound is added. In addition, regarding the performance of the nonwoven fabric, there is little change in texture due to the adhesion of chemicals or binders. Furthermore, it showed good residual performance in the immersion test, and in particular, in the case of an allantoin compound combined with a water-soluble resin that limited the amount of polyvinyl alcohol attached, the immersion test also showed an excellent residual rate.

In the case of Experimental Grade 5, the amount of polyvinyl alcohol attached was large, so the card passing property and opening property were poor.

(Effects of the Invention) The heat-adhesive short fibers of the present invention are fibers on which an allantoin compound having an anti-inflammatory effect is deposited, and by using this fiber and making it into a nonwoven fabric, it can be used for diapers and diaper liners. It is. Rather than adding allantoin compounds to conventional nonwoven fabrics.

Since it can be applied at the raw cotton manufacturing stage, the heat-adhesive short fibers of the present invention can be used alone or mixed with other materials, and are superior in terms of nonwoven fabric performance.

[Brief explanation of drawings]

FIG. 1 is a process diagram in which unstretched tow is stretched and crimped into short fibers. 1-----Kens 2-----1 Unstretched tow 3-----10th roller 4--1 20th roller 5--30th roller 6-----Crimping Apparatus 7 ------- - Dryer 8 ------- One cutter - A, B - - Allantoin compound application position Patent applicant Uni-Tei Riki Co., Ltd.

Claims (2)

[Claims] (1) An allantoin compound-containing heat-adhesive short fiber in which an allantoin compound is deposited on the fiber surface on which a polyolefin polymer is partially or completely exposed. (2) Allantoin compound-containing, characterized in that the allantoin compound is added after the crimping step in the heat-adhesive short fiber manufacturing process of fibers in which the polyolefin polymer is partially or fully exposed on the surface of the fibers. A method for producing heat-adhesive short fibers.