JPH01282389A - Nonwoven fabric containing allantoin compound and production thereof - Google Patents

Abstract

PURPOSE:To obtain the subject nonwoven fabric having excellent durability and exhibiting anti-inflammatory effect by using a nonwoven fabric containing a specific amount of fibers containing polyolefin polymer exposed to the surface and thermally fixing an allantoin compound to the surface of said polymer. CONSTITUTION:The base material for the objective nonwoven fabric is a nonwoven fabric containing at least 5% of fiber containing a polyolefin polymer exposed to a part or total of the surface of the fiber or a laminated nonwoven fabric having said nonwoven fabric as a surface layer. Solid particles of an allantoin compound are scattered on the surface part of said polyolefin polymer and are thermally fixed at a temperature not lower than the softening point of the polymer and below 245 deg.C. The obtained nonwoven fabric having thermally fixed solid particles of the allantoin compound exhibits anti-inflammatory effect because of the resistance of the solid particles to falling-off or little dissolution of the particles by urination. The nonwoven fabric is extremely suitable as diaper, etc.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is made by injecting an allantoin compound, which has a cell activation effect and a wound protection effect, in the form of solid particles onto the surface layer of a fiber made of a polyolefin polymer. This invention relates to nonwoven fabrics and their manufacturing methods.

(Prior art) Allantoin compounds have traditionally had excellent skin anti-inflammatory functions as cell activators and wound protection effects, and are compounds that have been widely used in pharmaceuticals, cosmetics, daily necessities, etc. by taking advantage of this performance. It is.

Recently, a new use of the above-mentioned allantoin compound, ``allantoin-added paper for diaper dermatitis,'' has been reported in ``Pediatric Clinical J vol, 30.1lh7゜P2.
S5 (1977). The allantoin-added paper is a sheet material made of rayon and cellulose nonwoven fabric to which an allantoin compound is added.

(Problems to be Solved by the Invention) Here, there are five methods for applying drugs using fibers as a support.
The following two methods have been proposed.

■ A method of wet paper making by dispersing it in water together with a binder ■ A method of applying a chemical in the form of an aqueous solution or aqueous dispersion to the fibers by spraying, impregnating, etc. However, in the former wet paper making method, the chemical is hidden by the binder. This poses a problem of falling off due to external force, etc. if rubbed during use. Furthermore, it is difficult to select a binder from the viewpoint of safety since it is used in parts that come into direct contact with the human body.

On the other hand, methods in which a chemical in the form of an aqueous solution or aqueous dispersion is applied to fibers require a drying step, but the treatment temperature must be strictly controlled in view of the thermal stability of the allantoin compound.

As mentioned above, although the application of drugs has been considered, there are still unsolved problems regarding nonwoven fabrics and their manufacturing methods that are economical, have less shedding due to physical friction, less elution of allantoin due to urination, etc. This is the current situation.

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

In other words, the present invention provides fiber A in which a polyolefin polymer is partially or completely exposed on the surface of the fiber.
An allantoin compound-containing nonwoven fabric, which is a nonwoven fabric B containing at least 5% or more of or a laminated nonwoven fabric C having the nonwoven fabric B as a surface layer, in which solid particles of an allantoin compound are heat-fixed to the surface layer portion of the polyolefin polymer, and the production thereof. The gist is the law.

The fibers A used in the present invention include fibers made of polyolefin polymers or fibers in which polyolefin polymers are exposed on part or all of the surface of single fibers, and the composite fibers include so-called bonded composite fibers,
Possible examples include core-sheath type composite fibers, eccentric core-sheath type composite fibers, and island-in-the-sea type composite fibers.

Among the composite fibers mentioned above, things to be careful of when manufacturing fibers are especially for bonded composite fibers.
It is necessary that both components do not separate during the spinning process and the cut-edge shrinking process.

Next, as the polyolefin polymer constituting fiber A, low density polyethylene, high density polyethylene, α-
Examples include linear low-density polyethylene obtained by copolymerizing olefin hydrocarbons, crystalline polypropylene, and copolymers thereof.

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 by merging two component polymers in a nozzle puncture or near a nozzle plate to form a composite fiber.

The composite ratio of composite fibers is the bulk required for practical purposes.

As long as it satisfies various properties such as strength, elongation, and texture, the composite ratio can be freely selected depending on the use and purpose, as long as it does not deteriorate the spinning properties. In addition, the fibers A may be made of either short fibers or long fibers, but 1 nonwoven fabric B
is short fiber non-woven fabric or.

It is made of long fiber nonwoven fabric, and the content of the above fiber A is 5.
% or more.

Fibers other than Fiber A include polyester, polyamide, rayon, pulp, acetate cotton, acrylic, wool, etc. By combining them, various properties such as texture and stiffness can be adjusted. It is possible to obtain a nonwoven fabric B that meets the intended use. Of course, if the content of fiber A is at least 5% or more, it is possible to heat-fuse with other materials without the need for other binders, and when made into a nonwoven fabric,
A nonwoven fabric with excellent strength can be obtained.

Further, by forming a laminated nonwoven fabric C in which another nonwoven fabric is laminated on the nonwoven fabric B, physical properties such as strength can be improved.

Allantoin compounds used in the present invention include allantoin (melting point 245°C), chlorohydroxyaluminum allantoinate (melting point 245°C) + sil::droxyaluminum 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 cm. All of the three types of allantoin compounds mentioned above are thermally unstable compounds that decompose near their melting points, and therefore, they are applied to fibers in a solid state at temperatures above the softening point of the polyolefin component and at 245°C. It is necessary to carry out heat fixing at temperatures below. In particular, since the allantoin compound is thermally unstable, it is desirable to thermally fix it at 200° C. or lower. The softening points of the polymers shown here are as per ASTM
This is the B-cut softening point specified in D-1525.

The amount of allantoin compound fixed to fiber A is not particularly limited, but is preferably 0.1 to 10% by weight. If it is less than 0.1% by weight, it will be poor in terms of cell activation effect and wound protection effect, while if it exceeds 10% by weight, the cost will be high and the above-mentioned cell activation effect etc. will not be much different from anything less than that. It is.

Next, the method of fixing the solid particles of the allantoin compound to the fiber A by heat is not particularly limited, but it can be produced by the following method.

The allantoin compound can be applied by directly spraying solid powder onto the nonwoven fabric containing fiber A, or by spraying an aqueous allantoin solution or an allantoin dispersion solution, applying with a roller, or dipping.

Next, the applied allantoin compound is thermally fixed at a temperature higher than the softening point of the polyolefin polymer and lower than 245°C. As the heating means, ordinary dyeing processing and heat treatment machines such as a roller dryer, a cylinder dryer, a pin tenter and a roll tenter can be used. The heat fixing time cannot be determined unconditionally depending on the type of polyolefin polymer, heating temperature, and form of the nonwoven fabric, but a few seconds to 5 minutes is sufficient.

The allantoin compound and the fibers A may be thermally bonded to each other after the nonwoven fabric B is produced by thermocompression welding, or after the nonwoven fabric B is produced before the nonwoven fabric B is produced.

(Function) The present inventors speculate as follows regarding the reason why the allantoin compound-containing nonwoven fabric of the present invention does not disappear from the fiber surface and remains even after dipping treatment.

Since the allantoin compound is fixed in the form of solid particles to the surface layer of the fiber made of polyolefin polymer, the amount of allantoin eluted during the dipping treatment is small. In addition, even if that part were eluted, new solid particles of allantoin compound buried in the fibers would reappear on the surface.

Cell activation effects and wound protection effects can be expected, and diaper rash will be prevented. Against this.

In the case of the conventional aqueous solution impregnation method, allantoin is only physically attached to the fiber surface and is not fixed to the fiber surface. For this reason, if you urinate - times.

Allantoin is easily eluted and the diaper rash prevention effect is lost.

In this way, only by thermally fixing the solid particles of the allantoin compound to the fibers A made of polyolefin polymer can an economical nonwoven fabric that is less likely to fall off due to urination, etc. be obtained.

(Example) Next, the present invention will be explained with reference to Examples.

First, 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 weight was taken and Al1 was quantified by one-point 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 (6 cm x 6 cm) of the allantoin compound-deposited nonwoven fabric was sampled and immersed in a metal vat filled with physiological saline for 5 minutes. Next, the allantoin nonwoven fabric that had been immersed was sandwiched between two glass plates of 7 cm x 7 cm, and a load of 1, 5 was applied.
kg was applied and left for 5 minutes. Thereafter, the nonwoven fabric subjected to the immersion treatment and pressure treatment was dried at 100°C. Seven lantoin compounds were quantified for 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 with a width of 30 mm and a length of 100 mm according to the strip method described in JISL-1096. Note that the strength in the lateral direction in Table 1 is sampled in the direction perpendicular to the machine direction.

Example 1. Comparative Example 1 High-density polyethylene with a melting point of 135°C is used as a sheath component.
Polyethylene terephthalate at 58° C. was used as the core component, the discharge amount was adjusted so that the weight ratio of both core and sheath components was 50:50, and composite spinning was performed at a spinning speed of 1200 m/min. Next, the obtained undrawn yarn was stretched at a stretching temperature of 90°C and a stretching ratio of 2 to 3 times, crimped with a crimper, dried, and cut to obtain a short fiber length of 2 denier x 511 cm. Obtained fiber. After opening the obtained short fibers, the fabric weight is 30g/
+d sheet was created.

Next, 1% was added to the seat weight so that it was 0.5 wt% (hereinafter, 1% by weight is abbreviated as -t%).
After temporarily adhering solid particle powder of dichlorohydroxyaluminum allantoinate to the surface of the sheet.

The fibers were passed through a continuous heat treatment machine set at 145° C. for a residence time of 2.5 minutes, and at the same time the solid particles of the allantoin compound were fused and fixed on the fiber surface, and then the fibers were air-cooled and wound into one roll. The amount of allantoin remaining in the obtained nonha cloth was determined by dipping treatment. The results are shown in Table 1. Note that the short fiber nonwoven fabric used in Example 1 was used as Comparative Example 1, and the adhesion of the allantoin compound to the nonwoven fabric was 0.5%.
After impregnating with the allantoin compound aqueous solution so that it adheres by wt%, it was heated at 100°C in the same manner as in Example 1 using the continuous heat treatment machine mentioned above.
The treatment was performed for 3 minutes. The results are shown in Table 1.

Example 2 Linear low density polyethylene copolymerized with octene-1 having a melting point of 125°C was used as a sheath component, polyethylene terephthalate with a melting point of 258"C was used as a core component, and stretched at a stretching temperature of 85°C and a stretching ratio of 2.1 times. Then, dihydroxyaluminum allantoine-1 was used as the drug.

An allantoin compound-containing nonwoven fabric was produced in the same manner as in Example 1 except that the continuous heat treatment temperature was 135°C. The results for the nonwoven fabric are shown in Table 1.

Table 1 □ Example 3 Polypropylene with a melting point of 164°C is used as a sheath component, and a melting point of 258°C is used as a sheath component.
℃ polyethylene terephthalate as the core component, the discharge amount was adjusted so that the weight ratio of both core and sheath components was 60:40, and the mixture was discharged as a jet stream together with 290℃ heated air attached to a composite linear nozzle. The web passed through a duct for opening the web, was collected on a moving collection wire mesh, and was wound into one roll. The average fineness of the long fibers obtained by one-method melt blowing was 0.
It was 5 denier.

Next, the laminate was needle-punched, with a basis weight of 50 g/m2.
I got a sheet of Next, 0.4 g of dihydroxyaluminum allantoinate in the form of solid particles was placed on the sheet.
Temporary adhesion was carried out at % by weight, and treatment was performed for a residence time of 3 minutes in a continuous heat treatment machine set at 180°C.

The results of the obtained nonwoven fabric are shown in Table 1.

Example 4 Linear low density polyethylene copolymerized with octene-1 having a melting point of 125°C was used as a sheath component, polypropylene with a melting point of 165°C was used as a core component, and the ratio of both core and sheath components was 60:40. The discharge amount was adjusted and composite spinning was performed at a spinning speed of 1000 m/min. Then, the obtained undrawn yarn was stretched at a drawing temperature of 70
After stretching at a stretching ratio of 2.3 times at °C, crimps were added using a crimper. After drying and cutting, 2 denier x 5
A fabric with a fiber length of 1 mm was obtained. After opening the cloth, the fabric weight is 30
A sheet of g/m was prepared.

Next, the amount of allantoin adhered to the sheet weight is 0.5.
After temporarily adhering dichlorohydroxyaluminum allantoinate to the sheet surface so as to achieve wt%.

The fibers were passed through a continuous heat treatment machine set at 140'C for a residence time of 2.5 minutes to thermally fuse the fibers together and thermally fix the allantoin compound at the same time, and after air cooling, the fibers were wound into one roll. Table 1 shows the results of the obtained nonwoven fabric.

Example 5 According to Example 1, a short fiber cloth of 2 d×51 ml was obtained.

Next, nylon 6 was melt-spun at a spinning speed of 1200 m/min. Then, the obtained undrawn yarn was drawn at a drawing temperature of 50
After stretching at a stretching ratio of 2.7 times at 9° C., crimping was performed using a crimper, drying and cutting to obtain cut cotton having a fiber length of 0.5 denier and 511 fibers. Defined fibers were mixed and opened so that short fibers made of core-sheath composite yarn and short nylon fibers each accounted for 50%, and a sheet having a weight per unit area of 30 g/m was prepared. Next, dihydroxyaluminum allantoinate was temporarily attached to the sheet surface in order to fix 0.2 wt % of the allantoin compound based on the sheet weight. Next.

The fibers were thermally fused and the allantoin compound was thermally fixed in a continuous heat treatment machine set at 145°C for a residence time of 2.5 minutes, and after cooling once in air, it was wound once. The results are shown in Table 1.

As is clear from Table 1, most of the nonwoven fabrics of Examples 1 to 5 remained on the surface of the nonwoven fabric even after the dipping treatment. On the other hand, in the case of Comparative Example 1, most of it was eluted and the durability was poor.

Example 6 Obtained in Example 1. Weight 30g/rI? The allantoin-containing nonwoven fabric of Example 1 was used as the surface layer, and the core-sheath composite yarn with the same composition as in Example 1 was made into continuous filaments with a single yarn fineness of 1.2 d using an air sucker, and the filaments were collected on a moving endless wire mesh. After that, after the empos roll, the first one (t
A nonwoven fabric sheet was created by laminating the obtained spunbond sheets of log/m. The tensile strength of the obtained nonwoven fabric in the transverse direction was measured. The results are shown in Table 2.

Table 2 shows that the lack of lateral strength of the short fiber nonwoven fabric can be overcome by forming a laminated nonwoven fabric with the long fiber nonwoven fabric, which can significantly improve the lateral strength. From these results, it was found that the nonwoven fabric of the present invention can also be used for nonwoven fabrics and laminated nonwoven fabrics suitable for various uses.

As explained above in the examples, a nonwoven fabric made by thermally fixing an allantoin compound to a part of a polyolefin polymer can be obtained, regardless of whether it is a short fiber nonwoven fabric or a long fiber nonwoven fabric, and furthermore, the texture can be adjusted by combining it with other materials. .

It can be seen that a powerful amplifier can be created by laminating layers.

(Effects of the Invention) The nonwoven fabric of the present invention is made of a nonwoven fabric in which an allantoin compound having an anti-inflammatory effect is thermally fixed to a portion of a polyolefin polymer, and can be used for sanitary products that come into direct contact with the skin, particularly diapers and sheets. In addition, in terms of manufacturing, it is possible to use conventional machinery and incorporate it into the conventional process without causing any thermal decomposition of the allantoin compound, making it possible to reduce costs. Since it does not disappear, it can be provided as a product with new functions.

Patent applicant: Unitika Co., Ltd.

Claims (2)

[Claims] (1) At least 5% of fiber A has polyolefin polymer exposed partially or completely on the fiber surface.
An allantoin compound-containing nonwoven fabric, which is a nonwoven fabric B containing the above, or a laminated nonwoven fabric C having the nonwoven fabric B as a surface layer, in which solid particles of an allantoin compound proboscis are thermally fixed to the surface layer portion of the polyolefin polymer. (2) At least 5% of fiber A has polyolefin polymer exposed partially or completely on the fiber surface.
After applying an allantoin compound in the form of solid particles to the nonwoven fabric B containing the above or the laminated nonwoven fabric C having the nonwoven fabric B as a surface layer, at a temperature higher than the softening point of the polyolefin polymer and lower than 245°C, A method for producing an allantoin compound-containing nonwoven fabric, which comprises thermally fixing solid particles of the allantoin compound.