JP2009505797A - Disposable footwear cover - Google Patents

Abstract

  The present invention relates to a disposable protective footwear cover suitable for use in sterile environments, highly controlled environments, medical facilities and industrial clean rooms.

Description

  The present invention relates to a disposable protective footwear cover suitable for use in sterile environments, highly controlled environments, medical facilities and industrial clean rooms.

  Workers entering highly controlled areas must wear clothing that does not contaminate the environment with materials released from the wearer's body. The garment must not have particles or fibers falling from the fabric. Clothes can also protect workers from light splashes of liquids and dry particulates.

  It is important for boots and shoe covers to prevent tracking particles throughout a very controlled area. Disposable footwear covers are used in the semiconductor and life sciences industries to prevent product contamination and the wearer's exposure to dangerous pathogens and materials.

  Current footwear covers present the wearer with the added risk of slipping and scooping as a result of excess material coming into contact with the floor. In use, the current footwear cover may hang down and drag the material to the floor, creating the risk of stumbling. Typical areas where such materials come into contact with the floor and are at risk include the heel and metatarsal areas.

  Patent document 1 is disclosing the shoe cover which cannot pass the liquid provided with the elastic band which completely surrounds a wearer's heel. This patent does not teach reducing the risk of slipping or scooping associated with the use of a shoe cover.

  Therefore, there is a need for a footwear cover that gathers excess material from the floor and prevents it from slipping, scooping, and rolling.

US Pat. No. 5,983,526

The present invention is a disposable footwear cover having an inner surface, an outer surface, a crus region, a heel region, a metatarsal region, a toe region, and a sole region, the cover comprising:
A flexible polymer sheet;
Elastic gathers in the lower leg area;
Elastic gathers in the metatarsal region,
Elastic gathers in the heel region,
It relates to a disposable footwear cover comprising a non-slip polymer coating covering at least 25 percent of the surface area of the sole region.

  The invention also relates to a process for manufacturing a disposable footwear cover.

  The present invention relates to a disposable protective footwear cover for use in sterilized environments, medical facilities, industrial clean rooms, and the like that uses elastic gathers and non-slip coatings to further protect the wearer from slipping, scooping and rolling.

  The disposable footwear cover of the present invention is made from a flexible sheet material and has an inner surface facing the wearer's foot or footwear and the wearer's foot or foot formed in the overall shape of a shoe, boot or foot. And an outer surface remote from the wear. The flexible sheet material can be woven or non-woven. The flexible sheet material is preferably a nonwoven fabric. The flexible sheet material can optionally include a coating cover on some or all of the surface to provide additional functionality, such as providing barrier properties. In addition, the flexible sheet material can optionally include bicomponent fibers to provide additional functionality, such as stability to gamma radiation for sterilization purposes. Bicomponent fibers are typically made of two different polymers and can be a combination of polyethylene, polypropylene or polyester. However, bicomponent fibers can be made from the same polymer with different properties. The bicomponent fibers may have a polymer sheath / core or side-by-side configuration. The flexible sheet material useful in the present invention is typically selected such that it is impermeable to liquids and additionally serves as a barrier that protects the wearer from the dangers of blood, chemicals, and the like. .

  The flexible sheet material further preferably functions as a barrier to particle permeation. More preferably, the flexible sheet material can prevent greater than 85 percent transmission of particles larger than 0.5 micrometers. Most preferably, the flexible sheet material can prevent greater than 93 percent permeation of particles greater than 0.5 micrometers.

  Flexible sheet materials suitable for use in the present invention include, but are not limited to, microporous films, polyesters and polyolefins. The flexible sheet material preferably comprises polypropylene or polyethylene. Polyethylene is preferred, for example TYVEK available from EI Du Pont De Nemours and Co., Wilmington, DE, Wilmington, Delaware. (Registered trademark). A flexible sheet material suitable for use in the present invention can be produced by methods known in the art such as hydroentangling, carded thermal bonding, spunbonding or meltblowing.

  As shown in FIG. 1, the present invention is a disposable footwear having an inner surface, an outer surface, a lower leg region 35, a heel region 30, a metatarsal region 20, a toe region 25, and a sole region 28. Cover 10. The disposable footwear cover 10 includes an elastic material that collects excess sheet material to provide an improved snug fit. As used herein, the term “elastic gather” refers to elastic bands, threads, etc. attached to a flexible sheet material. Referring to FIG. 1, elastic gathers 50, 60 and 70 typically have a lower leg region 35 that includes an area from about 2 cm below the knee to about 2 cm above the heel, about 2 cm above the heel to about 2 cm below the heel. In each of the heel region 30 including the region up to and the metatarsal region 20 including the region from the vicinity of the thumb ball to the heel, each is disposed on the inner or outer surface of the footwear cover. The elastic gathers 50 arranged in the lower leg region are typically arranged so as to surround the boot cover opening. The width of the elastic gather is typically less than about 2 cm. The elastic gather is preferably less than about 1 cm wide. Most preferably, the elastic gathers are elastic threads. Elastic gathers are typically made of materials such as spandex, natural rubber, polyurethane, and combinations thereof. The elastic gather can be attached to or incorporated into the flexible sheet material of the footwear cover. Typical means of attaching or incorporating elastic gathers include stitch bonding, adhesives, stitching and tunneling (strips are sewed into footwear by surrounding the elastic body with a strip such as flexible sheet material. Is attached).

  The elastic gathers 50 in the lower leg region typically surround at least a portion of the wearer's leg and can completely surround the wearer's leg. The elastic gathers 50 in the lower leg region can be extended to all or part of the periphery of the lower leg region. The elastic gathers 50 in the lower leg region preferably cover only a part of the wearer's leg to facilitate wearing. More preferably, the elastic gathers 50 in the lower leg region surround a part of the back side of the wearer's leg. Most preferably, the elastic gathers 50 in the lower leg region surround approximately 30-80 percent of the circumference of the wearer's leg in the contact area.

  The elastic gathers 60 in the heel region are typically positioned to collect excess footwear cover material and provide a snug fit. The heel region elastic gathers 60 can extend all or part of the periphery of the heel region 30. The heel region elastic gathers 60 preferably extend approximately 25 to 80 percent around the heel region 30 of the footwear cover. More preferably, the elastic gathers 60 in the heel region further extend around the back of the heel. Most preferably, the heel region elastic gather 60 extends approximately 25 to 60 percent around the heel region 30 of the footwear cover including the back of the heel.

  The metatarsal region elastic gathers 70 are typically arranged to gather the excess material of the footwear cover, reduce the chances of wrinkling, and provide a snug fit. The metatarsal region elastic gathers 70 typically extend beyond the metatarsal region 20 from approximately one end of the sole to approximately the opposite end of the sole.

  A method of manufacturing a disposable footwear cover is illustrated in FIGS. 2A-2F. In FIG. 2A, two tapered sheets 100 and 100 'are provided. Each has a narrow end a and a 'and a wide end b and b'. The dimensions of each sheet are about 35 cm long, about 9 cm at the narrow end, and about 12 cm at the wide end. As illustrated in FIG. 2B, the sheets 100 and 100 ′ are aligned and fixed together along the narrow ends a and a ′, and also fixed along the long ends for distances c and c ′, A small opening T is formed at the top and a large opening B is formed at the bottom. The distance c or c 'can be about 15 cm. As illustrated in FIGS. 2C and 2D, a third sheet 104 having ends d and d ′ and end e (about 35 and about 30 cm, respectively) is secured by fixing the ends d and d ′ together. A cylinder. As shown in FIG. 2E, the current peripheral end e of the cylinder 104 is fixed to the end f of the small opening T to form most of the foot cover 10 including the crus region 35 and the heel region 30. Can do. A sheet material (for example, an ellipse of about 33 cm × 15 cm) having a suitable shape and size piece with rounded ends h is fastened to the end g of the large opening B to form the sole sheet 28. As shown in FIG. 1, together with the footwear cover material before assembly, the elastic gathers 70 are disposed beyond the metatarsal region in a direction extending from one end of the sole to the other end of the sole. The elastic gathers 60 are arranged around the back surface of the heel region 30, and the elastic gathers 50 are arranged around the upper part of the lower leg region 35. The elastic gathers 60 or 70 can be incorporated either before or after the sole sheet 28 is attached.

  Referring to FIG. 2F, the disposable footwear cover of the present invention incorporates a polymer coating 32 on a portion of the outer surface of the sole region 28. The sole region 28 usually provides a high coefficient of friction to minimize the risk of slipping or rolling in contact with the floor. The polymer coating desirably has a high coefficient of friction on both wet and dry surfaces. The polymer coating can be continuous, discontinuous, pattern, islands, dots and combinations thereof. As shown in FIG. 2F, the polymer coating 32 is preferably applied to areas that support the heaviest parts during use, such as the toes and heels of the foot. More preferably, the polymer coating 32 covers at least about 25 percent of the area of the sole region, more preferably the polymer coating covers at least about 50 percent of the sole region, most preferably the polymer coating 32 is the sole Cover at least about 80 percent of the area. The polymer coating 32 typically comprises materials such as polyester, polyolefin (eg, polyethylene or polypropylene), polyvinyl chloride, polyurethane, rubber, and combinations thereof. The polymer coating preferably comprises polyethylene, polyvinyl chloride or rubber. Suitable embodiments of the coat portion of the sole of the footwear cover include polyvinyl chloride coated polyester scrim, polyethylene coated polyethylene sheet and rubber coated polyethylene sheet. The polymer coating typically has a coefficient of static friction greater than about 1.5. The coefficient of static friction of the polymer coating is preferably greater than about 2.5. Most preferably, the coefficient of static friction of the polymer coating is greater than about 3.0.

Test Method The coefficient of friction is the dimensionless ratio of the friction force between two objects (F) to the normal force (N) that presses these objects together. The coefficient of friction is determined according to ASTM D1894.

  The static coefficient of friction is the coefficient of friction that corresponds to the maximum friction force that must be overcome to initiate a macroscopic motion between two objects. The coefficient of static friction is determined according to ASTM D1894.

The side view of a footwear cover is shown. Fig. 4 shows a process step for manufacturing a footwear cover.

Claims (12)

A disposable footwear cover having an inner surface, an outer surface, a crus region, a heel region, a metatarsal region, a toe region, and a sole region, the cover comprising:
A flexible polymer sheet;
Elastic gathers in the lower leg region and elastic gathers in the metatarsal region,
Elastic gathers in the heel region,
A disposable footwear cover comprising a non-slip coating covering at least 25 percent of the surface area of the sole region.   The disposable footwear cover according to claim 1, wherein the flexible polymer sheet comprises a material selected from the group consisting of polyolefin and polyester.   The disposable footwear cover according to claim 2, wherein the flexible polymer sheet comprises polyethylene.   The disposable footwear cover according to claim 1, wherein the flexible polymer sheet is a nonwoven fabric.   The disposable footwear cover according to claim 1, wherein the flexible polymer sheet is a woven fabric.   The disposable footwear cover of claim 1, wherein the polymer coating has a coefficient of static friction greater than about 1.5.   The disposable footwear cover according to claim 1, wherein the non-slip coating comprises a material selected from the group consisting of polyvinyl chloride, polyolefin, polyester, rubber, polyurethane, and combinations thereof.   The disposable footwear cover according to claim 7, wherein the non-slip coating comprises polyester.   The disposable footwear cover according to claim 8, wherein the polyester is coated with polyvinyl chloride.   The disposable footwear cover of claim 1, wherein the flexible sheet material blocks more than about 85 percent permeation of particles having an average diameter greater than about 0.5 micrometers.   11. The disposable footwear cover of claim 10, wherein the flexible sheet material blocks more than about 93 percent permeation of particles having an average diameter greater than about 0.5 micrometers. Providing two polymer sheets each having two long sides and a taper from a wide end to a narrow end;
Attach the two sheets together at the narrow end of the taper,
Two sheets are attached together on each long side for a partial distance to form a small opening and a large opening on the opposite side,
Providing a third sheet,
Forming a third sheet into a cylindrical shape;
A third cylindrical sheet is attached to the small opening,
Providing foot sole sheet,
Attach the sole sheet to the large opening,
Attach elastic gathers to the lower leg area,
Attach elastic gathers to the metatarsal region,
The method of manufacturing a footwear cover according to claim 1, comprising attaching an elastic gather to the heel region.

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