JPH01314773A - Nonwoven fabric for medical use - Google Patents

Abstract

PURPOSE:To obtain the subject product having excellent dust-proofing property, air-permeability and lint-free property by laminating and bonding a web layer composed of cellulosic fiber having specific fiber length to a web layer composed of ultrafine synthetic fiber. CONSTITUTION:The objective product having a dust-proofing ratio of >=30% is produced by laminating (A) a web layer composed of a cellulosic fiber having a fiber length of >=20mm and (B) a web layer composed of synthetic fibers having an average fineness of <=0.1 de and fixed with each other with an adhesive at a crossing region of the fibers and bonding the web A to the web B with an adhesive. The fiber of the web A is preferably a continuous long fiber. The above product can be produced, e.g., by applying an adhesive by a printing process to the web layer B formed by melt-blow spinning process, laminating the separately produced web A to the web B and passing the laminate through a gap between a pair of rolls to effect the bonding of the web layers.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to medical nonwoven fabrics. More specifically, the present invention relates to medical nonwoven fabrics suitable for use in disposable surgical gowns, patient gowns, and the like.

[Conventional technology]

Treating an assemblage of wood pulp fibers and synthetic organic fibers with a narrow columnar jet of water having an orifice supply pressure of at least 6900 kpa to entangle the constituent fibers, thereby obtaining a spunlaced nonwoven fabric. A method is disclosed in Japanese Patent Application Laid-Open No. 59-94659.

This nonwoven fabric is used for medical purposes by taking advantage of its bacterial barrier properties.

[Problem to be solved by the invention]

The nonwoven fabric is formed into a dense structure and has excellent bacteria barrier properties, but when actually used in the medical industry, there is a problem in preventing the bacteria contained in the fabric from penetrating when blood adheres to the material. It is said that

In addition, in medical applications, it has been pointed out that if fine fiber debris, so-called lint, is floating in the operating room, it can adhere to the patient's surgical site and cause infection from the bacteria attached to the lint. Ru.

For this reason, medical gowns are required to be lint-free. The conventional nonwoven fabrics mentioned above use extremely short fibers called wood pulp, so when the nonwoven fabric rubs with other fabrics, equipment, or the human body, the pulp turns into lint. The problem is that it is easy to do.

The present invention aims to solve the problems of conventional nonwoven fabrics as described above, and to provide a medical nonwoven fabric that has higher bacteria barrier properties and excellent lint-free properties than conventional nonwoven fabrics.

That is, as mentioned above, medical nonwoven fabrics used for gowns, drapes, etc. are required to have high bacteria barrier properties. The size of bacteria is 0.15 Ja ~ in diameter
It is said to be around 3 rabbits. A nonwoven fabric with a dense structure is desired to capture these microscopic bacteria, but
It is extremely difficult to satisfy both of the contradictory characteristics that the denser the material, the worse the air permeability.

On the other hand, a method for easily evaluating the bacterial barrier property is to use the dustproof rate (%) instead.

Dust-proofing rate is a measurement value obtained from the difference in concentration by simultaneously measuring the upstream and downstream concentrations of a test specimen with two detectors under a flow of monodisperse particles under certain conditions. The better the bacteria barrier properties.

According to the research conducted by the present inventors, a dustproof rate of 10% is not sufficient to provide a sufficient bacterial barrier property, as measured by the dustproof rate measurement method described below. % or more, more preferably 40% or more.

Based on these findings, it is an object of the present invention to provide a medical nonwoven fabric having a dustproof rate of 30% or more, good air permeability, and excellent lint-free properties.

[Means to solve the problem]

The object of the present invention is to provide a web layer made of cellulose fibers having a fiber length of at least 20 mm and an average fineness of 0.
a web layer made of synthetic fibers of 1 denier or less, the constituent fibers of which are fixed to each other with an adhesive at their intersection areas, and the two (4) layers are laminated and joined with an adhesive; 3
This is achieved by a medical nonwoven fabric characterized by having a dustproof rate of 0% or more.

As the synthetic fibers having an average fineness of 01 denier or less (hereinafter referred to as ultrafine fibers), relatively long fibers of 20 mm or more are preferably used. The web layer made of ultrafine fibers, preferably long fibers, can form a dense layer on the web layer made of cellulosic long fibers. As a result, the grouper barrier properties are further improved and lint-free properties can be exhibited.

The web layer made of synthetic fibers (ultrafine fibers) having an average fineness of 0.1 denier or less is a web made of fibers of polyamide, polyester, polypropylene, polyacrylonitrile, and copolymers thereof, or a mixed web thereof.

In addition, the average fineness of the constituent fibers of the ultrafine fiber web forming the dense layer must be 0.1 denier or less, preferably 0.05 denier or less, and if it is larger than this, the dustproofing rate cannot be achieved.

The manufacturing method is not particularly limited, but the desired ultrafine fiber web can be easily obtained by melt blow spinning and flash spinning.

For example, by using the melt blowing spinning method disclosed in Japanese Unexamined Patent Publication No. 63-6107 filed by the same applicant as the applicant of the present invention, ultrafine fibers having an average fineness of 0.01 denier can be spun. A web formed by uniformly arranging such ultrafine fibers can have a basis weight of 7 g/m' or more, but if it is less than 10 g/m', it is insufficient as a dense layer, and if it is more than 50 g/m', it is difficult to ventilate. The preferable range is 15 g/m' to 40 g/m.
'is.

The adhesive applied to the ultrafine fiber web layer may be freely selected as long as it does not cause any harm to the human body.

Examples include acrylic ester, cyanoacrylate, polyurethane, and styrene-butadiene rubber latex.

In addition, a web layer formed of ultrafine synthetic fibers has water repellency and can be used in the above-mentioned gowns to prevent blood, medical fluids, etc. from penetrating in medical settings. However, if the water repellency is reduced by applying an adhesive or dyeing, the water repellent may be mixed with the adhesive.

The web layer made of cellulose fibers functions as a support layer for other layers, and at the same time improves the feeling of wearing when used as the above-mentioned gown.

In particular, it has high hygroscopicity, so it feels nice on the skin when worn and has excellent moisture absorption (sweat) properties.

The cellulose fiber wafer layer of the medical nonwoven fabric of the present invention,
A web made of either regenerated cellulose fibers such as cuproammonium rayon or viscose rayon, or natural cellulose fibers such as cotton; for example, a web formed by aligning fibers with a card and subjected to fiber entanglement treatment;
Alternatively, it is a wet spunbond nonwoven fabric. In addition, the fiber length is relatively long, 20 mm or more, preferably 28 mm or more, and more preferably continuous fibers. If it is less than 20 mm, the fiber entanglement treatment by water jet will not be carried out sufficiently, and lint will likely be generated due to surface friction. In this respect, those made of continuous long fibers are preferable because of their high abrasion resistance.

The two webs that make up the nonwoven fabric are laminated and bonded in a subsequent process.

For example, a web layer made of ultrafine fibers is formed using a melt blow spinning method, and an adhesive is applied using a printing method.
Thereafter, a separately formed web consisting of cellulosic long fibers is laminated on the web, passed between two rolls and bonded, and then dried to obtain a nonwoven fabric.

At this time, by applying an adhesive to the web layer made of ultrafine fibers, the constituent fibers are fixed and integrated in the alternating areas. This improves the abrasion resistance of the surface of the web layer.

Next, an example of the medical nonwoven fabric of the present invention will be shown.

Continuous filaments of cuproammonium rayon were used as the web layer consisting of cellulosic fibers with a basis weight of 4.
A web layer of 0 g/m' was formed.

This web has excellent porosity as a nonwoven support layer. On the other hand, a web layer made of ultrafine polypropylene fibers with an average fineness of 0.01 denier and a basis weight of 20 g/m' was formed, and an adhesive was applied to the ultrafine fiber web layer at a rate of 7 g/m'.
A medical nonwoven fabric was obtained by laminating and adhering cellulose fibers.

This nonwoven fabric has a basis weight of 67 g/m', a thickness of 0.4 +n+n, which is extremely thin, and has excellent flexibility. Therefore, a sewn disposable surgical gown is easy to wear because it has good sleeve loops, and is comfortable to wear because it has high moisture absorption.

Furthermore, the surface has fibers fixed with adhesive, and the back side has long fibers intertwined to increase wear resistance, so the lint will remain strong even when it comes into contact with other objects or the human body. Occurrence is extremely rare.

In addition, although the web layer formed using ultrafine fibers is extremely thin, it has an excellent dustproof rate of 30% to 70%, compared to 10% for conventional web layers. In addition, the breathability is also better than conventional ones. In other words, it has excellent bacteria barrier properties and is comfortable to wear. In addition, it is possible to prevent the adhesion and penetration of airborne bacteria, etc., or the penetration of bacteria, etc. contained therein even if blood is attached in a medical field.

〔Example〕

The present invention will be explained in detail with reference to Examples below.

Prior to describing the examples, the definitions and measurement methods of characteristic values used in the examples will be collectively shown.

◎Basm weight: 250x250 mm from standard sample
After collecting three samples and allowing them to reach a water equilibrium state,
Measure the weight (g) and calculate the average value per unit area (g /
m').

◎Abrasion resistance: Standard sump knob width 25mm x length 2
A 50 mm piece was rubbed using a Gakushin type bending friction tester (manufactured by Takasugi Seisakusho) under conditions of a load of 200 g and 50 times of friction. After rubbing, accurately collect a small piece of sample 2j x 25 mm, approximately 2 g,
Fill an ultrasonic cleaner (Yamato, 822ON) with 250 cc of water, wash for 15 minutes, remove the sample piece, collect the fallen lint on black filter paper, dry it, adjust the humidity, and measure its weight using a microbalance. . The higher the amount (mg) of phosphorus, the worse the wear resistance.

◎Dust-proof rate - Under the flow of monodisperse particles under certain conditions, the upstream and downstream concentrations of the test specimen are measured simultaneously with two detectors and determined as the dust-proof rate (%).

Stearic acid aerosol with an average diameter of 0.3p was used as the monodisperse particles. The flow rate was set at 2.1 cm/sec, and the measurement time was 1 minute. The measuring device is 5IBATA Dig
ital Dust Indicator Model
AP-632 was used.

Dustproof rate (%) = (1-D2 /D,)X100D,
: Upstream photo counter D2 : Downstream photo counter The higher the dustproof rate (%), the better the bacterial barrier property.

◎ Air permeability: The raw fabric area of 26+nmφ (5.3 cut) is expressed as the flow rate (β) of air passing through in 1 minute at a pressure of 10 cm-820.

Example 1 A web layer made of cellulose fibers was produced according to the method for producing a regenerated fiber spunbond nonwoven fabric described in Japanese Patent Publication No. 52-6381. That is, using a rectangular spinning funnel device, a copper ammonia rayon spinning stock solution is spun,
A liquid film containing a large number of filaments is caused to flow down from the lower slit of the spinning funnel device and is continuously collected on an advancing net conveyor, subjected to purification treatment and further water jet treatment. This was applied to rearrange the fibers and then dried to produce a web (referred to as cupro web) consisting of continuous filaments (single yarn 15d) of cupro ammonium rayon and having a basis weight of 40 g/m'.

Separately, a web made of ultrafine polypropylene fibers was produced according to the melt blow spinning method described in JP-A-63-6107. That is, polypropylene resin was put into an extruder, heated and melted, and melt blown under the following conditions. A large number of orifices each having a diameter of 0.3 mm were lined up in a nozzle provided in the die, and the molten polymer was discharged from these orifices. In addition, heated steam was injected from slits on both sides of this orifice, and the molten polymer was made into a draw wire, and the fiber group was collected on a moving net conveyor to form a web layer. Gui temperature 290 t:, gas temperature 370℃, gas pressure 5.0 kg/c++t G
Met. At that time, the conditions were changed and the basis weight was 7 g/m.
', 10g/m', 15g/m', 20g/m', 40
g/m' and 50 g/m'. The fibers were formed to have an average fineness of 0.01 d and a fiber length of 300+ nm. Next, the web layer was glued with an adhesive (Dainippon Ink KK,
The web layer is passed between a print roll and a pressure roll to which an acrylic ester adhesive has been applied, then an adhesive is applied to the web layer, and then a separately manufactured cupro web that is rolled is laminated. The medical nonwoven fabric of the present invention was obtained by passing the fabric between two rolls and adhering it, and then drying it in a dryer.

Table 1 shows the combinations of webs and the characteristic values of the obtained nonwoven fabrics.

As can be seen from Table 1, the products of the present invention have a lower abrasion resistance of 85 mg to 105 mg, compared to 45.0 mg of the conventional product, and are found to generate less lint.

The ultrafine fiber web having a basis weight of 7 g/m' has a low dustproof rate of 3%, which is insufficient as a dense layer. The same product with <10 g/m' has a dustproof rate of 13%, which is almost the same as the 10% of the conventional product. The same <15 g/m' to 5 g/m' shows a dustproof rate of 32% to 70%, and achieves the object of the present invention.

In addition, the breathability of the product of the present invention is 36% compared to 351% of the conventional product.
n~1411, and has excellent air permeability despite having a high dustproof rate.

Example 2 According to Example 1, a web made of ultrafine polypropylene fibers was produced. At that time, the average denier is 0.
．． 1d, 0.05d, and 0.01d, and the basis weight was 2'Og/m'. Then, an adhesive was applied in the same manner as in Example 1, and this web was laminated with the same cupra web having a basis weight of 40 g/m' manufactured in Example 1 to obtain a medical nonwoven fabric of the present invention. Table 2 shows the characteristic values of the obtained nonwoven fabric.

Table 2 (I5) The smaller the value, the higher the dustproof rate. If the average fineness is 0.1 d or less, the object of the present invention can be achieved. Also,
It is more preferable if it is 0.05d or less.

〔Effect of the invention〕

According to the present invention, a medical nonwoven fabric is provided in which a web layer made of ultrafine synthetic fibers and a web layer made of long cellulose fibers with excellent hygroscopicity are laminated and bonded together.

This nonwoven fabric has a dustproof rate of 30% or more, so it has a high bacteria barrier property, and in medical settings, it does not allow airborne bacteria to adhere or pass through, or even if blood adheres to it, the bacteria contained in it. Transmission can be prevented.

In addition, this nonwoven fabric has excellent breathability despite its high dustproof rate, and combined with the hygroscopicity of the cellulose long fiber web, it is a comfortable material to wear.

Furthermore, since it is thin and highly flexible, and uses a simple manufacturing process, it can be manufactured at low cost, and can therefore be used for disposable surgical gowns, patient gowns, and the like.

Claims (1)

[Claims] A web layer consisting of cellulose fibers with a fiber length of at least 20 mm or more, and a web layer consisting of synthetic fibers with an average fineness of 0.1 denier or less, whose constituent fibers are fixed to each other with an adhesive at their intersection areas. A medical nonwoven fabric comprising: the two layers laminated and bonded by an adhesive; and having a dustproof rate of 30% or more.