JP2006507416A - Clothing for protecting body parts against biological agents - Google Patents

Abstract

The present invention relates to a garment made of polypropylene and polyethylene and suitable for partial protection of the body, especially suitable for a barrier against biological substances. The garment offers a very high level of protection against liquid penetration and microbial intrusion, and excellent mechanical properties including abrasion resistance, excellent flexibility, drapeability, and comfort.

Description

Detailed Description of the Invention

〔Technical field〕
The present invention relates to clothing suitable for protection against biological agents.

[Background Technology]
There are various situations where workers are exposed to infectious biological agents. Infectious biological agents include microorganisms containing genetically modified organisms that can cause infection, allergies and toxicity. In some situations, such as microbial laboratories, biotech production sites, etc., infectious agents are generally well known.

  In other tasks, such as farming, waste disposal, especially hospital waste disposal, veterinary laboratories, and emergency cleaning activities, the chemicals to which workers are exposed may not be well known. The assessment is based only on potential risks.

  Under these circumstances, protective clothing is needed to prevent infectious agents from reaching the skin. Protective clothing can be manufactured from disposable or reusable fabrics. Attempts to meet the standards for a safe, effective and comfortable protective barrier have developed many excellent fabrics and production techniques.

  For reusable fabrics, from the early 20th century to the early 1970s, we started with cotton that was not water-resistant and easily passed through liquids, to polyester / cotton blends with improved mechanical properties, and waterproof chemistry Fabrics have been developed for use in finished and tightly knitted cotton or polyester / cotton blends.

  In the 1980's, a new generation of fabrics was developed, such as tightly woven fibers consisting of continuous filament yarns and possibly fine filaments (microfibers). These can be chemically finished and can be calendered to increase liquid penetration resistance. All of the above fabrics are formed by an interlocking geometry to provide a safety and protective barrier.

  Disposable protective garments are generally composed of non-woven fabric and are manufactured by fiber bonding techniques (thermal, chemical, or physical) to provide safety and strength. The basic raw materials are various types of natural fibers (eg cotton, wood pulp) and synthetic fibers (eg polyester, polyolefin).

  The woven fabric can be designed to reach the desired properties by using a special type of fiber, the bonding process and finishing.

  In short, fibers are mechanically (spun lace method) by high-speed water jets that entrain the fibers, thermally by in-line melt spinning (spun bond method), or chemically by chemical binder (wet method). Can be glued.

  Nonwoven fabrics are primarily made from polyolefins.

  Both reusable and disposable products are often reinforced to enhance and improve properties. In special applications, it is often the case that the raw material to be added is added (in whole or in part) in the form of a layer, coating, reinforcing agent or laminate of the raw material.

  In particular, the second layer of fabric is used to improve liquid penetration and slip resistance. Also, chemicals are used to obtain reinforcement and liquid resistance characteristics.

  Various protective garments obtained by the above-described processing are described, for example, in EP 033555559B1 (priority GB87714535).

  Polyethylene is one of the most commonly used fabrics, and several types are manufactured for different uses.

  In addition, Tyvek® protective material is a spunbond olefin made from fine continuous filaments of high density polyethylene that are bonded together by heat and pressure.

  Such fabrics are described, for example, in EP850330 and US4322171.

  In particular, there are gowns made from such fabrics, which have high resistance to liquids, powders, and chemical resistance, but are cut-resistant, wear-resistant, draped, flexible, flexible and breathable. It is not very effective for ease of use.

  Given that the protective material must be strong enough to withstand the stresses encountered in normal use and that the comfort-related properties are of utmost importance in a very dangerous work environment, All such properties are as important as protective properties.

  Thus, a new protective garment with a more improved effect because it can provide an appropriate level of protection against liquid penetration and microbial intrusion, while at the same time providing properties in other important performances including mechanical resistance and comfort Finding it is a constant necessity.

[Summary of the Invention]
We have found new garments made of polypropylene and polyethylene that are effective in protecting certain parts of the body, particularly suitable as a barrier to biological agents.

  The garment of the present invention has a very high level of protection against liquid penetration and microbial invasion, excellent mechanical properties including tear resistance and abrasion resistance, excellent flexibility, drapeability, and comfort Gowns, jackets and trousers.

  The present invention relates to a novel garment suitable for partial protection of the body against biological agents.

  The garment is composed of a layer of non-woven polypropylene laminated with a polyethylene film, and the weight ratio of polypropylene to polyethylene is in the range of 70:30 to 50:50, preferably 65:35 to 55:45. .

The garment, unit weight is typically thick 240~270μ nonwoven polypropylene layer is 35~45g / ^{m 2,} unit weight thickness in 30~70μ is a 20 to 30 g / ^{m 2} Laminated with a polyethylene film.

The total thickness of the dough is 270 to 340 μm and the unit weight is 55 to 75 g / m ² .

In particular, the garment is a non-woven polypropylene layer having a thickness of 245 to 255 μm and a unit weight of 37.5 to 40.0 g / m ² , and a thickness of 40 to 60 μm and a unit weight of 22.5 to 27.27. It is preferably laminated with a polyethylene film of 5 g / m ² . In this case, the thickness of the garment is preferably 285 to 315 μm, and the unit weight is preferably 60.0 to 67.5 g / m ² .

  The inner layer consists of a nonwoven spunbond fabric made from continuous filaments of polypropylene.

  In addition to providing barrier properties against liquids and microorganisms, the inner layer ensures high drape and comfort, as well as physiological safety and breathability.

  The outer layer is small enough to prevent liquid penetration and microbial invasion, and in addition to that, it has micropores with pores that allow moisture in the air to pass through at the molecular level to ensure high air permeability. Made of porous polyethylene film.

  The combination of the two fabrics in each shape and in the right proportions gives a combination of properties that can never be reached with previously known partial body garments, such as chemical and physical properties, drape and comfort. Can be provided.

  In particular, the fabric flexibility, which ensures high drape and excellent comfort under any circumstances, does not adversely affect the barrier properties against liquids and microorganisms. And the said cloth | dough is the same or more barrier property with respect to a liquid and microorganisms compared with the high-density conventional cloth | dough.

  Furthermore, the tear and wear resistance is strong enough to withstand the stresses encountered during use in any hazardous situation.

  The objects of the garment of the present invention include gowns, outerwear, and trousers. The garment is designed according to the specific requirements of the current law, in particular the instructions 686/89 (Italian DL 475 04.12.92).

  There are various types of clothing, for example clothing in foundries only protects specific parts of the body, so to protect the rest of the body, gloves and other protection Must be worn in combination with clothing.

  More specifically, the gown and outerwear of the present invention can be connected to the trousers of the present invention. For example, FIG. 1 shows a front view (1a) of a gown for protecting exposed parts of the body, such as the base of the neck, chest, arms, and legs to the knee.

  The gown is provided with a rubber band to ensure a perfect fit around the wrist to isolate the arm from contact with possible dangerous elements. All joints are joined by heat welding, and the joints ensure high barrier properties equivalent to the fabric. The gown is easy to wear and the back (1b) is open so that it can be closed by four rear fixtures, two on the inside and two on the outside.

  The garment is designed and manufactured to avoid areas that irritate or adversely affect the wearer. For example, the gown is accurately measured and the wearability and roughness are evaluated. Checked gowns are D.04 / 12/92. L. n. It meets 475 safety and health requirements and is manufactured in accordance with the provisions of ergonomic regulations EN340 / 94.

  The garments are manufactured in a plurality of sizes in order to be comfortable for any worker in any work environment and to prevent the garments from being damaged.

For example, the dimensions in cm of different size gowns that meet EN340 rules are listed in the table below. The values in the table include a tolerance of ± 3%.
Size S M L
Length 110 120 130
Chest 130 134 140
(Thorax circumference)
Shoulder width 56 59 62
Sleeve width 58 59 62
The measurement was performed according to the test method of ISO3635 / '81 under a normal environment where the temperature is 20 ° C. and the relative humidity is 65%.

  The manufacturing method is based on the normal manufacturing rules for protective clothing. Cut the dough, make holes, select different members based on size, and number them. And the said clothing is manufactured by checking the dimension of a different member and heat-welding a different member. At that time, the label is affixed to the inside of the clothing.

  In addition to the manufacturer name, the label includes a model number, a reference pictogram, a size, and a pictogram representing “Resident Evil”. In particular, the garments are labeled according to the European Standard (CE) for protective clothing against biological agents.

  The information for the wearer is unambiguous and clearly written, and the CE label is clear evidence to ensure that it meets basic safety and health requirements. FIG. 2 shows an example of a label.

  At the end of the manufacturing process, the manufacturing process is checked by checking that all the members are correctly connected and that the structures of the different layers and the different layers to be stacked are in accordance with the work instructions. Management is performed. Special checks are made for sealing of the welded area, display compatibility and display position.

  Finally, in order to protect the clothing until it is used, the clothing is folded and pre-stitched, and the information is folded and packed.

  The garments thus produced are suitable for protection against biological agents such as bacteria, parasites, fungi and viruses.

  The garments are effective against any microorganisms, including genetically modified organisms, cell cultures, and human parasites that can cause infection, allergies, and toxicity.

  In particular, the garments include microorganisms such as hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV) transmitted by blood and body fluids, causative agents of BSE and other TSE, and Effective against Bacillus Anthracis.

  The garments can be used in any situation where an operator may be exposed to various forms, such as liquid, air, aerosol, or solid, and various types of hazardous materials.

  Examples of work environments at risk of exposure to infectious substances include biotechnology production sites, health care work (including isolation and dissection equipment), chemistry and biology work, veterinary and medical laboratories, Examples include working at a waste disposal site, and interacting with animals and / or animal-derived products.

  The above garment may be worn on top of normal work clothes, but the effect is not guaranteed unless it is worn correctly, that is, unless an appropriate size is worn.

  In the following, the results of some tests conducted to evaluate the technical properties of the gown will be described. Such results are merely examples, and the scope of the present invention is not limited thereto.

(Barrier properties)
The main property of protective clothing is the effect of a suitable level of protection against microbial invasion.

  The liquid is generally accepted to be the most important vector carrying microorganisms. However, other possible vectors, including air and aerosols, as well as dry invasion of microorganisms facilitated by mechanical action are also possible.

Therefore, an effective barrier to microorganisms must be able to resist the invasion of microorganisms in both wet and dry conditions.
In order to measure the barrier properties of the gown according to the present invention, a series of tests (Tests 1 to 3) were performed.

(Test 1)
Resistance to infiltration of contaminated liquid under hydrostatic pressure This test measures the resistance of a dough against invasion by pathogens carried to the blood using alternative pathogens under continuous liquid contact.

The test is divided into the following two procedures.
(A) Using artificial blood simulating blood and other body fluids, subjecting the fabric to continuously increasing pressure, the penetration of the artificial blood into the fabric is visually observed. This procedure (a) is used as a screening test.
(B) Measure resistance to invasion of surrogate pathogen into the dough. Alternative pathogens that are microorganisms act as mimics of other microorganisms that are pathogenic to humans.

  Artificial blood mimics body fluids. Many factors, such as body fluid surface tension, viscosity, and polarity, can affect body fluid invasiveness and permeability. The surface tension range of blood and body fluids (excluding saliva) is approximately 0.042 to 0.060 N / m.

  The range of the surface tension of the imitation product is adjusted to 0.042 (± 0.002) N / m, which is substantially the minimum value of the surface tension range.

  The alternative pathogen used in this study is bacteriophage phi-X174, which serves as a pseudovirus that is not pathogenic to humans but is pathogenic to humans.

  The surrogate pathogen is one of the smallest known viruses with a diameter of 0.027μ and a size and shape similar to the smallest blood pathogen HCV with a diameter of 0.03μ. Therefore, bacteriophage phi-X174 also acts similarly to HBV (0.042μ) and HIV (0.10μ).

(Test results)
(1a) Screening Test for Resistance to Artificial Blood This test method uses artificial blood having different hydrostatic pressure levels and is intended for measuring the resistance of a protective fabric against invasion by biological fluid.

  The test is based on ASTM F1670 and is used as a screening test.

  The test is performed on three randomly selected specimens of 75 mm × 75 mm at an air temperature of 25 (± 5) ° C. and a relative humidity of 52%, and each pressure is maintained for 5 minutes.

  The penetration of the artificial blood into the fabric can be visually observed for each specimen under different pressures, and if it does not penetrate, it passes (P), and if it penetrates, it records a failure (F). did.

The test results are as follows.
Pressure (Kpa) Sample 1 Sample 2 Sample 3
0 P P P
1.75 P P P
3.50 P P P
7.00 P P P
14.00 P P P
20.00 P P P
Similar results were obtained even when the test was repeated for the heat-welded part.
(1b) Method for testing resistance to invasion of infectious substances using bacteriophage phi-X174 The test uses bacteriophage phi-X174 as a test system to test the resistance of the protective fabric against invasion of infectious substances. This is done by measuring.

  The test is based on ASTMF1671 and applies only to fabrics that have passed the screening test (a).

  The test was performed on three specimens of 75 mm × 75 mm randomly selected from the fabric.

  The specimens were exposed to a culture medium containing a virus-containing nutrient that was continuously pressurized at an air temperature of 21 (± 5) ° C. every 5 minutes.

  Detection of microbe invasion at each pressure was performed even when liquid penetration was not visible.

  If the applied hu / ml (plaque forming units / milliliter) penetrating the liquid is less than 1 under the applied pressure, the specimen shall pass the test. A fabric has passed the test when all three specimens have passed the test under the applied pressure.

The results are as follows.
Pressure Sample 1 Sample 2 Sample 3
14Kpa 0hu / ml 0hu / ml 0hu / ml
(Test 2)
Resistance tests against the entry of biologically contaminated aerosols were performed in a Parspex box equipped with a Collison atomiser.

  A solution containing the microorganism Staphylococcus aureus ATCC 6538 (NCIMB9518) was sprayed into the box. An underpressure is performed to collect the contaminated aerosol droplets on the two membrane filters. One of these filters is protected by protective clothing fabric.

  And the filter was removed, microorganisms were extracted, and after culturing overnight at 37 ° C., the number of microorganisms was calculated.

  The barrier properties of protective clothing fabrics were evaluated by using the percentage of bacteria found on the protected and unprotected filters.

  Four specimens (circular with a diameter of 25 mm) were tested in 7 minutes.

The results for microorganisms that entered through the dough are as follows.
Sample 1 Sample 2 Sample 3 Sample 4
0% 0% 0% 0%
(Test 3)
The resistance test against the entry of biologically contaminated dust is based on the EDANA method 190.0-89 / '96.

  The powder was contaminated with spores of Bacillus subtilis ATCC 9372 (CIP A4) and shaken through protective clothing fabric for 30 minutes.

  The number of microorganisms that invaded through the dough was calculated after culturing at 35 ° C. for 24 hours.

  The test was performed on six specimens measuring 200 mm × 200 mm, and one of the specimens was used as an uncontaminated object.

The results are as follows.
Specimen 1 2 3 4 5 Reference microorganism 0 0 0 0 0 0 0
(mechanical nature)
Other properties such as durability against mechanical stresses encountered during normal use that damage the fabric and consequently adversely affect barrier properties are important in assessing the performance of the fabric.

  In order to evaluate the mechanical properties of the garment, several tests (tests 4-8) were carried out.

(Test 4)
Abrasion resistance is determined according to Martindale method and J.A. Measurements were taken with a Heal machine using 00 abrasive paper.

  The test was performed on four specimens at an air temperature of 20 (± 2) ° C., a relative humidity of 65%, and a pressure of 9 Kpa until one hole having a diameter of 0.5 mm was opened in the fabric (evaluated with a stereoscopic microscope).

The result is expressed in the period required until the first hole is opened.
Specimen 1 2 3 4 Average period 2880 3300 2500 2500 2795
According to this method, the fabrics are classified into four types, with the highest category being level 4 (> 500 cycles), indicating the fabric with the highest wear resistance.

  Thus, according to tests, the fabric of the present invention shows the highest resistance to damage during use.

  The following is a list of results based on tests performed to assess other mechanical properties.

(Test 5)
Tear resistance Trepezoidal method-UNIENISO9073 / '99
Longitudinal tear strength = 59.4 (± 10.1) N
Transverse tear strength = 35.2 (± 5.7) N
(Test 6)
Bending crack resistance method ISO7854 / '84
The specimens did not show any damage up to 100.000 cycles at 10x.

(Test 7)
Tensile strength (Grab method)
Method UNI EN ISO 13935-2 / '01
Sample: 100 x 250 mm
Air temperature: 20 ± 2 ℃
Relative humidity: 65%
Average breaking strength = 72.2 (± 4.6) N
(Test 8)
Puncture resistance method UNI EN 863 / '96
Puncture resistance = 12.4N
(Resistance to ignition)
There are many things that can cause ignition in the normal use of protective clothing. All doughs burn when exposed to a strong heat source, especially when the oxygen concentration is high.

  The test was conducted to evaluate the flame retardancy of the garment of the present invention.

(Test 9)
The flame retardant test is based on the EN 1146 / '97 method using propane gas and a Bunsen burner according to the EN / 532 / '94 rule and a flame of 800 (± 50) ° C. height 40 mm.

Five specimens were evaluated as having no evidence of combustion or incandescence.
(Resistance to chemicals)
The fabric can come into contact with chemicals such as clinical liquids, skin disinfectants, lubricants, and oils in normal use.

  Since such chemicals damage the fabric and consequently affect the barrier properties, it is of utmost importance that the protective garment has sufficient resistance to chemicals.

  The test was performed using four different liquid chemicals.

(Test 10)
The resistance test against penetration of liquid chemicals is based on the UNI EN588 method.

  Three specimens were tested using four different chemicals at an air temperature of 20 (± 2) ° C., a relative humidity of 65%, and a flow rate of 10 ml / 10 (± 1) seconds.

  Several parameters are evaluated and a list of average values is shown below.

Penetration (%) Repel (%) Absorption (%)
H ₂ SO ₄ 30% 0 86.4 8.6
NaOH 10% 0 86.0 10.2.
n-Heptane 0 78.7 7.0
Isopropanol 0 82.1 8.4
(Resistance of seam part)
Finally, a special water penetration test was performed on the joints in consideration of the ease of liquid penetration at the seams, seams and joints of the protective clothing.

(Test 11)
The resistance test for water penetration under increasing hydrostatic pressure is based on the UNI EN20811 / '93 method, which is carried out using a TEXTTEST FX3000 device and increasing the water pressure at a rate of 60 cm / min.

  The test was conducted at an air temperature of 20 ± 2 ° C., a relative humidity of 65%, and a water temperature of 20 ± 2 ° C.

The results are shown in cm H ₂ O and Pa required at the seam for the third water droplet to penetrate through the dough.

cm H ₂ O Pa
Sample 1 280 27500
Sample 2 304 29800
Sample 3 282 27700
Specimen 4 206 20200
Sample 5 266 26100

It is a front view which shows the clothing of this invention. It is a rear view which shows the clothing of this invention. It is a front view which shows an example of the label attached to the clothing of this invention.

Claims (14)

Manufactured by laminating a layer of polyethylene and a layer of polypropylene,
The body's resistance to biological agents with exceptional mechanical properties, excellent flexibility, draping, and comfort, including a very high level of protection against liquid penetration and microbial invasion, tear resistance and abrasion resistance New protective clothing suitable for partial protection.   The new protective garment according to claim 1, wherein the new protective garment is a gown, a jacket, or trousers.   The inner layer is a non-woven polypropylene layer, the outer layer is made of a polyethylene film, and the weight ratio of the polypropylene to the polyethylene is in the range of 70:30 to 50:50. New protective clothing as described in.   2. The inner layer is a non-woven polypropylene layer, the outer layer is made of a polyethylene film, and the weight ratio of the polypropylene to the polyethylene is in the range of 65:35 to 55:45. New protective clothing as described in. The thickness of the said cloth is 270-340 micrometers, and the unit weight of the said cloth is 50-70 g / m < ² >, The novel protective clothing of Claim 3 characterized by the above-mentioned. The inner layer of the nonwoven polypropylene layer has a thickness of 240 to 270 μm and a unit weight of 35 to 45 g / m ² .
4. The novel protective clothing according to claim 3, wherein the outer polyethylene film has a thickness of 30 to 70 μm and a unit weight of 20 to 30 g / m ² . The thickness of the said cloth is 285-315micro, The unit weight of the said cloth is 60.0-67.5g / m < ² >, The novel protective clothing of Claim 3 characterized by the above-mentioned. The inner layer of the nonwoven polypropylene layer has a thickness of 245 to 255 μm and a unit weight of 37.5 to 40.0 g / m ² .
4. The novel protective clothing according to claim 3, wherein the outer polyethylene film has a thickness of 40 to 60 μm and a unit weight of 22.5 to 27.5 g / m ² .   The novel protective clothing according to claim 1, wherein the joint portion is joined by heat welding. With a rubber band around the wrist,
To protect the neck,
The gown according to claim 2, further comprising a fixing device provided with a total of four fasteners, two on the inner side and two on the outer side.   Claim 1 as protective clothing against biological agents that are microorganisms (bacteria, parasites, fungi, and viruses) including genetically modified organisms, cell cultures, and human endoparasites that can cause infection, allergies, and toxicity. Use of the new protective clothing as described in 1.   The method of using a novel protective clothing according to claim 11, wherein the biological agent is a microorganism (HBV, HCV, and HIV) transmitted by blood and body fluid.   The method of using a novel protective clothing according to claim 11, wherein the biological agent is a causative substance of BSE or other TSE.   The method for using a novel protective clothing according to claim 11, wherein the biological agent is a Bacillus anthracis bacterium.

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