WO1997007273A1

WO1997007273A1 - Nonwoven fabric or silk for medical supplies

Info

Publication number: WO1997007273A1
Application number: PCT/JP1996/002271
Authority: WO
Inventors: Takashi Ninagawa
Original assignee: Silk Kogei Co. Ltd.
Priority date: 1995-08-11
Filing date: 1996-08-07
Publication date: 1997-02-27

Abstract

Silk fibers are cut into short fibers having a length of about 1 to 10 cm, from which a nonwoven fabric is prepared by needle punching or water stream entanglement without using any binder. This nonwoven fabric has a satisfactory liquid absorbency and is so soft that it does not damage the internal tissues. It is therefore suitable for medical supplies such as surgical gauzes. Scoured silk fibers are used for surgical gauzes, while both scoured and unscoured silk fibers are used for sheet and so forth.

Description

Technical Description Medical silk nonwovens Technical field

The present invention relates to a medical nonwoven fabric used for gauze, bandages, sheets, surgical gowns and the like. Background art

Some of the so-called surgical gauze include an affected gauze used to protect the tissue during surgery, a square gauze (wiper) used for absorption and wiping, and our gauze used for surgical procedures (Dressing).

Surgical gauze has the following roles:

① Absorption of blood and wastewater

② Partition of the surgical site

③ Tissue, organs, incised tissue protection and cushioning

To fulfill these roles, surgical gauze is required to have the following characteristics. a. High X-ray contrast and easy counting

b. Easy to fold and open

c Functionally sufficient dry and wet strength

d. Low lint and resistance to fraying

e. Fast liquid absorption and high absorption

f. Do not cause trauma to the tissue surface when contacting the tissue

, g. Optimal fluid retention for tissue hydration

h. Steam and gas can be sterilized by radiation

i. High-speed machining, low cost

j. Compliance with safety and toxicological standards

In order to meet such demands, the affected area gauze is currently made of rayon cotton and spunlace blended with polyester for strength. Have been done. In addition, cotton yarn woven gauze is used for dressing to absorb or protect wound exudate. Generally, this gauze is basically 30 cm in width and is cut or folded according to the size of the wound. However, it is difficult to use the lint after cutting or to fold it. (Medical non-woven fabric handbook, supervised by the Japan Society of Medical Instruments, October 1998, published by Nanzando Co., Ltd.)

On the other hand, nonwoven fabrics are widely used in the medical field, such as sheets and surgical gowns, but most of the nonwoven fabrics conventionally used are made of synthetic fibers such as nylon and polyester.

Conventional cotton yarn woven gauze has been used for a long time, and its safety has been proven.However, in addition to the drawbacks of the above-mentioned lint, the wound absorbs a large amount due to insufficient liquid absorbency. In that case it had to be replaced many times. In addition, cotton yarn gauze appears to be soft at first glance, but has a disadvantage that it is relatively hard on body tissue and makes fine scratches on the surface of body tissue. In addition, cotton fibers were not always sufficiently compatible with tissues in the body, and if some of the fibers remained in the body, it was inevitable that rejection would occur.

The present invention has been made to solve such problems, and one of the objects thereof is to have sufficient absorbency, sufficient softness not to damage body tissues, and An object of the present invention is to provide a surgical gauze with less rejection from body tissues. It also provides materials that can be widely used for other medical uses. Disclosure of the invention

The medical nonwoven fabric according to the present invention, which has been made to solve the above-mentioned problem, is characterized in that the medical nonwoven fabric is made of only short fibers obtained by cutting silk fibers. Therefore, no binder (adhesive) is used to fix the fibers.

The silk fibers may be unrefined or refined. Unrefined products can be produced at low cost, so they are suitable for use in sheets, blankets, medical clothing, and the like. It is also suitable for applications that require a high degree of chemical rejection, because there is no risk of residual chemicals during scouring. On the other hand, by performing scouring, part or all of the sericin layer on the surface is removed, and at the same time, dirt on the surface is also removed. When required, it is desirable to use refined silk fibers. Such scoured silk fibers are used for surgical gauze such as the affected area gauze, wiper, and dressing described above. However, in this case, perform sufficient de-chemical treatment after scouring.

The length of the short fiber is about l to 10 cm. If the length is shorter than this, the entanglement becomes insufficient and the print tends to occur. In addition, even if the length is longer than this, the entanglement does not work well, and the nonwoven fabric has a lot of fraying. In addition, it is more preferably about 5 to 7 cm. As the entanglement for forming the silk short fibers into a nonwoven fabric, any of a needle punching method and a hydroentanglement method used in general nonwoven fabric production can be employed.

In the case of the needle punch method, the nonwoven fabric according to the present invention is produced as follows. First, unrefined or refined raw silk fibers (filament fibers) are cut into appropriate lengths to make short fibers. This is removed by carding to remove short fibers of less than a predetermined length and impurities to form a sliper. Before the carding, different types of silk fibers may be mixed (mixed). Slivers generated continuously are cut at appropriate intervals by Athenyue. At this time, cut the sliver so as not to cut the short silk fiber.

A slicer cut to an appropriate length is placed on a net, and the net is vibrated to form a fleece (fiber accumulation layer). Keep the fleece slightly moist. As a method of giving moisture to the fleece, a method such as spraying fog water on the fleece or increasing the humidity of the atmosphere can be used. This removes static electricity due to friction between the silk fibers, prevents separation between the silk fibers due to static electricity, and facilitates formation of a fleece. Further, in the needle punching step described later, the degree of adhesion between the needle and the fiber is increased, and the entanglement of the fiber is facilitated.

Next, the rotatable blade supported by the hanging bar is inserted into the moving fleece. The blades rotate as the fleece moves, stirring the silk fibers in the fleece and removing short waste fibers (dust).

And the fiber is entangled by repeatedly passing the needle through the fleece, Obtain an integrated nonwoven. Finally, the thickness is made uniform by pressing with a heating roller.

In the case of the water entanglement method, a high-pressure columnar water stream is similarly sprayed onto the filtered fleece to entangle the fibers.

As the surgical gauze, any one produced by the needle punch method or the hydroentanglement method can be used. However, when emphasis is placed on the liquid retention ability (the ability to absorb and hold blood and other liquids) The one manufactured by the 21 dollar punch method is more suitable, and the one manufactured by the hydroentanglement method is more suitable when emphasis is placed on strength or low lintability.

For gauze, about 50 to 200 g / mm ² when manufactured by the 21 dollar punch method, and about ²⁰ to 100 g Z mm ² when manufactured by the hydroentanglement method (preferably ²⁰ mm (Approximately 60 g / mm ² ) is appropriate. Also, the length of the silk fiber used as the raw material should be slightly longer in the case of the hydroentanglement method than in the case of the needle punch method. BEST MODE FOR CARRYING OUT THE INVENTION

When used as surgical gauze, it is sterilized by ripening with Simmel Kettel or the like, as with conventional gauze. Although the nonwoven fabric of the present invention is made of silk, its properties do not change as long as it is subjected to heat sterilization treatment or gas sterilization treatment (EOG) similar to conventional cotton yarn gauze. Further, as with the conventional surgical gauze, a urethane thread or the like for X-ray detection may be embedded.

The medical non-woven fabric according to the present invention includes, in addition to the surgical gauze described above, a bandage, a base cloth for a patch, a gauze for an emergency bandage (also referred to as a wound tape, for example, a brand name band aid), a surgical gown, a mask, Can be used for sheets, filters, etc. Of course, it is desirable to appropriately change the basis weight and the like according to each of these uses. The invention's effect

Conventionally, silk sutures have been used for surgical sutures, and it has already been demonstrated that there is no problem with human compatibility. It is also known that silk fibers are less likely to cause allergies. The nonwoven fabric according to the present invention is composed only of silk fibers. Therefore, it can be used with confidence even on parts that directly touch the skin or body tissues. The results of examining the allergic properties of silk fiber by comparison with rabbit hair are described below. The experimental method used is as follows. First, 5 mg each of silk fiber and rabbit hair are subcutaneously planted in an ICR mouse (a type of hybrid mouse). Three weeks later, mice were inoculated with a solution (0.1% aqueous solution) of the same silk fiber or rabbit hair dissolved in water having a weight of 100 times the weight (0.1% aqueous solution), and the thickness of the footpad was measured. The strength of the allergic reaction was examined by the weight of the popliteal lymph node and the weight of the popliteal lymph node.

Table 1 Delayed-Type Hypersensitivity (Experiment 1)

Footpad thickness (10 m) Antigen Antigen-inoculated side. Inoculated saline side Increased amount Silk (0.1% aqueous solution) 1 325 340 -15

2 335 335 0

3 335 330 5

4 325 315 10

Mean soil SD 330 ± 6 330 ± 11 0 ± 11 Rabbit hair (0.1% aqueous solution) 1 380 325 55

2 385 335 50

3 380 340 40

4 375 320 55

Mean soil SD 380 ± 4 330 ± 9 50 ± 7 Weight of popliteal lymph node (nig) Antigen Inoculated antigen side Inoculated saline side Increased amount Silk (0.1% aqueous solution) 1 2.5 3.2 —0.7

2 3.3 3.3 0

3 3.3 3.4 -0.1

A 9 A 9 <i n 1

Mean soil SD 2.88 ± 0.49 3.05 ± 0.51-0.18 ± 0.36 Rabbit hair (0.1% aqueous solution) 1 5.8 2.1 3.7

2 6.1 2.9 3.2

3 3.7 3.5 0.2

4 5.1 3.6 1.5

Mean soil SD 5.18 ± 1.07 3.03 ± 0.69 2.15 ± 1.61 Silk fiber or rabbit hair (5 mg) was subcutaneously implanted in ICR mice, and after 3 weeks, 1000 times the weight of the raw material of silk fiber or rabbit hair (0.1% aqueous solution) ) Was inoculated into a footpad, and the allergic reaction was examined. Table 2 Delayed-Type Hypersensitivity (Experiment 2)

Footpad thickness (10 m) Antigen Antigen inoculated side Inoculated saline side Increased amount Silk (0.1% aqueous solution) 1 300 300 0

2 295 290 5

3 300 300 0

4 '310 305 5

Mean soil SD 301 ± 6 299 ± 6 3 ± 3 Rabbit hair (0.1% aqueous solution) 1 340 300 40

2 345 300 45

3 350 295 55

4 35-5 310 45

Mean soil SD 348 ± 6 301 ± 6 46 ± 6 Weight of popliteal lymph node (mg) Antigen Antigen inoculated side Inoculated saline side Increased amount Silk (0.1% aqueous solution) 1 2.1 1.9 0.2

2 1.8 1.9 -0.1

3 1.8 1.7 0.1

4 1.8 1.8 0

Meaner SD 1.88 ± 0.15 1.83 ± 0.10 0.05 ± 0.13 Rabbit hair (0.1% aqueous solution) 1 3.1 1.6 1.5

2 4.6 2.4 2.2

3 4.2 1.8 2.4

4 2.7 1.9 0.8

Mean soil SD 3.65 ± 0.90 1.93 ± 0.34 1.73 ± 0.73 Silk fiber or rabbit hair (5 mg) was inoculated subcutaneously into ICR mice, and after 3 weeks, 1000 times the weight of the silk fiber or rabbit hair material (0.1% aqueous solution) ) Was inoculated into a footpad, and the allergic reaction was examined. Tables 1 and 2 summarize the results of the two experiments, respectively, for both the thickness of the footpad and the weight of the popliteal lymph node, for the 0.1% silk solution. The increase was nearly zero, whereas a 0.1% rabbit hair solution showed a significant increase. That is, it has been experimentally proved that silk fibers hardly cause allergy.

Next, the medical nonwoven fabric according to the present invention is made of silk, so that it is soft and hardly makes any fine scratches on the surface even when the body tissue is wiped. In addition, the silk fiber itself has a large liquid absorption capacity, and a relatively densely packed nonwoven fabric can improve the liquid absorption capacity depending on the tissue. A gauze having a liquid absorption capacity about 2 to 5 times that of cotton gauze can be obtained. Therefore, when used as a wiper during surgery, a relatively small amount of gauze can be sufficiently absorbed by simply applying it without wiping as in the past, so that the affected part can be seen better, and rapid And it will greatly help the progress of certain operations. Further, even if the surface of internal organs or the like is wiped with the gauze according to the present invention in order to see the affected part better, the surface of the tissue is rarely damaged. Furthermore, since it is composed of only silk fibers, which are animal fibers without impurities, it does not stimulate the internal organs, wounds, etc. even if they come into contact with them. There are few problems. In addition, since it is made of silk fiber, which is a natural material, there is no problem of disposal after use, unlike nonwoven fabric using synthetic fibers.

Claims

The scope of the claims

1. Medical silk non-woven fabric consisting only of short fibers obtained by cutting silk fibers.

2. Medical non-woven silk fabric obtained by entanglement of short fibers obtained by cutting silk fibers by the needle punch method.

3. The medical silk nonwoven fabric according to claim ² , wherein the basis weight is 50 to 200 gZmm2.

4. Medical silk non-woven fabric made by entanglement of short fibers obtained by cutting silk fibers by a hydroentanglement method.

5. basis weight 20~ 100 gZmm ² a is 4. The medical silk nonwoven fabric according.

6. basis weight 20 to 60 g / mm ² a is 4. The medical silk nonwoven fabric according.

7. The medical silk nonwoven fabric according to any one of claims 1 to 6, wherein the length of the short silk fibers is 1 to 10 cm.

8. The medical silk nonwoven fabric according to any one of claims 1 to 6, wherein the length of the silk short fibers is 5 to 7 cm.

9. The medical non-woven silk fabric according to any one of claims 1 to 6, wherein the silk fiber is unrefined.

10. The medical silk nonwoven fabric according to any one of claims 1 to 6, wherein the silk fiber is refined.

1 1. Surgical gauze made of short fibers obtained by cutting scoured silk fibers to 1 to 10 cm and entangled by the needle punch method.

12. basis weight 50~200 gZmm ² a surgical gauze of claim 1 1, wherein.

13. Surgical gauze formed by entangled short fibers obtained by cutting scoured silk fibers to 1 to 10 cm using the hydroentanglement method.

14. basis weight is 20 ~ 100 gZmm ² claims 1 to 3, surgical gauze according.

1 5. basis weight 20 ~ 60 gZmm ² a surgical gauze of claim 13, wherein.