EP1294245B1

EP1294245B1 - Garment assembly

Info

Publication number: EP1294245B1
Application number: EP01940768A
Authority: EP
Inventors: James Ferguson Findlay
Original assignee: WL Gore and Associates UK Ltd
Current assignee: WL Gore and Associates UK Ltd
Priority date: 2000-06-29
Filing date: 2001-06-19
Publication date: 2004-10-20
Anticipated expiration: 2021-06-19
Also published as: AU7426901A; CA2414350A1; DE60106614T2; DE60106614D1; EP1294245A1; AU2001274269B2; GB2364002A; CA2414350C; GB0016014D0; GB2364002B; ATE279867T1; JP2004502050A; WO2002001977A1; US20030167551A1

Abstract

A garment comprises an outer shell (4) and an inner liner (2). The inner liner is a liquid-water-resistant and water-vapour-permeable material (particularly coated expanded polytetrafluoroethylene membrane) which has a discontinuous pattern of abrasion-resisting polymeric material on the side which faces the outer shell. The pattern may be a pattern of dots (26) of abrasion-resisting polymer. The outer shell may be removable from the inner liner.

Description

The present invention relates to a garment assembly comprising an outer shell and an inner liner; and to a liner for use in the assembly. In particular, the invention relates to a garment assembly wherein the inner liner is water-resistant and water-vapour-permeable and the outer shell is fixed or replaceable.

Garments comprising an inner liner which is water-resistant and water-vapour-permeable and which have a replaceable outer shell are known. The replaceable outer shell is generally attached to the inner liner in a removable manner e.g. by zips or press-studs, and gives the wearer the flexibility to choose the colour or fabric of the outer shell independently of the nature of the inner liner (which imparts the necessary water-resistance and water-vapour-permeability). Water-resistance means that under normal conditions of wear, the garment is impervious to penetration by liquid water. Water-vapour-permeability is the ability for moisture exuded from the body of the wearer to pass through the inner liner so as to prevent build up of moisture inside the garment, making it uncomfortable to wear.

A known construction of such a garment involves an inner liner formed of an expanded polytetrafluoroethylene (ePTFE) membrane having a water-vapour-permeable polymeric coating on an inner surface thereof facing the body of the wearer. In order to protect the water-resistant water-vapour-permeable membrane, a knitted material is normally laminated to the outer side of the membrane to protect against abrasion with the outer shell of the garment. However, a problem with this known construction is that under rainy conditions, water penetrates the outer shell and wets the outer facing knitted layer of the inner liner. This knitted layer becomes saturated with water and gives the garment a clammy feel to the wearer and also adds extra weight. This derives from the water absorbancy and retention properties of the knitted materials conventionally used on the outer side of the liner.

A further problem with this known constructions is that it is sometimes difficult to seam-seal the seams of the inner liner to provide the required water-resistance to the liner as a whole, due to the presence of the outward facing knitted layer. As is known, water-resistant water-vapour-permeable garments of this type are generally seam-sealed to provide water-tightness by applying a tape over seams in the garment to prevent water ingress through the seams.

It is an object of the present invention to mitigate these disadvantages.

Patent publication WO99/35926 discloses a waterproof water-vapour-permeable textile assembly for providing protection against heat or cold when used in a garment, and particularly for providing good thermal insulation properties. The textile assembly comprises a porous stretched polyurethane membrane coated with a water-vapour-permeable polyurethane and adhered to a backing fabric. A pattern of silicone bumps of height about about 508 to 1270 microns (0.02 to 0.5 inches) is formed on the backing fabric. The silicone bumps space the coated membrane from the outer shell, thereby providing good heat insulation.

GB 2 316 341 discloses a water proof water-vapour-permeable garment comprising a abrasion resisting layer of dots.

Broadly speaking, the present invention provides a discontinuous pattern of polymeric material over the outward facing side of the water-resistant water-vapour-permeable liner, so as to resist abrasion between the liner and the outer shell. However, the abrasion-resistant polymeric material does not have the disadvantage of becoming wetted by rain to any significant extent.

In particular, the present invention provides A garment which comprises:

an outer shell (4) surrounding an inner liner (2);
the inner liner comprising a water-resistant water-vapour-permeable material having a first side and a second side; the first side facing the outer shell, the water-resistant water-vapour-permeable material comprising a substrate (20) coated with a hydrophilic film (22) forming the first side (24), and a discontinuous pattern of abrasion-resisting polymeric material being provided over said first side; the discontinuous pattern of abrasion-resisting polymeric material being in the form of dots (26) having a height of 50 to 500 microns.

The invention also relates to the inner liner per se having attachment means for attaching to an outer garment shell.

The outer garment shell may in principal be formed of any fabric or other material suitable for this purpose. It can be made of any suitable weight of fabric, though lightweight fabrics are preferred to avoid making the overall garment too heavy. Generally, the fabric will be one which retains water to a minimal extent and is fast drying. It may be treated with a conventional shower-proofing coating, including water repellant coatings or impregnations. The outer shell may surround the inner liner either completely or incompletely. For example, if the inner liner includes sleeves, the outer garment could be in the form of a vest or waistcoat covering only the body part of the inner liner and leaving the sleeves free.

The outer shell may be fixed to the inner liner. However, a particularly preferred embodiment, the outer shell is removable and interchangeable. For example, a number of outer shells may be provided, each differing in terms of colour or fabric or each carrying different logos or wording. For example, a paramedic arriving at an emergency scene might attach onto his inner liner an outer shell bearing particular wording, such as "Supervisor".

The outer shell is preferably removeablp attached to the inner liner by conventional attachment means, such as zips, press studs, hooks, hook and eye fasteners e.g. Velcro (trademark). Typically, the outer shell is attached to the inner liner by a pair of zips extending down either side of the front opening of the garment. Thus, the outer shell and the inner liner are usually only loosely attached to one another and there is a spacing between.

The inner liner comprises a water-resistant water-vapour-permeable material. Suitable materials are disclosed in patent specification GB2316341A. Thus, a preferred material comprises a woven or non-woven substrate, typically formed from expanded polytetrafluoroethylene (ePTFE) coated on the first side facing the outer shell with a water-resistant water-vapour-permeable hydrophilic film of the type disclosed in patent specification US 4,194,041. The polymer is generally a hydrophilic polymer such as a polyurethane or polyester. The hydrophilic polymer may include a filler such as disclosed in patent specification GB9921103.9; nanometer sized carbon particles being particularly preferred in view of the improved abrasion resistance that they impart.

The discontinuous pattern of abrasion-resisting material may be in the form of continuous lines or grids or in the form of unconnected bodies of abrasion-resisting polymer, such as dots, chevrons, discrete lines or other unconnected shapes. The dots may be any shape (in plan-view), such as squares,circles, ovals, rectangles, polygons etc. In order to minimise abrasion of the outer shell, shapes having sharp corners are not preferred. Preferably, the dots are truncated pyramidal, truncated hemispherical, hemispherical or part-spherical in three-dimensional shape. Generally, the polymeric material is partially raised from the surface of the hydrophilic material and the raised profiles are preferably smooth to avoid snagging of the inner liner against the outer shell.

The pattern of dots may be a random pattern or an orderly pattern according to a predetermined spatial geometry. Each dot preferably has a maximum diameter of 200 to 2000 microns, preferably 500 to 1000 microns. The dots may be spaced apart centre-to-centre by 250 to 3000 microns, particularly 800 to 1200 microns. The dots have a height above said first side of 50 to 500 microns, preferably of 100 to 400 microns.

Typically, the abrasion-resisting polymeric material covers 30-80%, preferably 40-75% and typically 50-70% of the first side of the material of the inner liner.

The abrasion resisting polymeric material may include a prepolymer which cures in situ, a UV light-curable polymer, a room temperature vulcanising polymer, or a thermoplastic polymer. The polymeric material may be applied to the substrate in liquid form from a hot melt, by solution coating or by emulsion coating. Suitable elastomeric polymers include polyesters, polyvinylchloride, polyamides, silicones, polyurethanes, or polyurethane-polyester composites. Reactive polyurethanes, such as blocked polymers, whose reactive groups unblock above a certain temperature are especially useful. The cured polymer will generally be resistant to conventional dry-cleaning solvents. Conventional application methods includes screen printing, gravure printing and spraying. The polymeric material may be water-vapour-permeable or not, and the particular polymer will be chosen such that the water-vapour-permeability of the inner liner is within chosen limits.

A conventional textile lining may be laminated to the second side or inner side of the liner material.

The water-vapour-permeability (MVTR) of the inner liner will generally be at least 1,000 or preferably at least 1500 and most preferably greater than 3,000 g/m²/day.

The water-resistance of the inner liner is measured by the suter water-resistance test. An acceptable practical indication of water-resistance is one in which there is no evidence of water being forced through a sample by a pressure of 1.4lbs per sq.inch (0.1kg/cm²) or more typically 2.0lbs per sq.inch (0.14kg/cm²).

Abrasion resistance is measured employing a Martindale abrasion machine of the type described in J.Text.Inst. 1942:33, T151. After a predetermined number of rubs, the material is removed and tested for water-resistance until a leak is detected.

TEST METHODS TEST FOR MOISTURE VAPOUR TRANSMISSION RATE (MVTR) (Potassium Acetate Method)

Moisture vapour transmission rate (MVTR), i.e. water-vapour-permeability, was measured by placing approximately 70 ml of a solution consisting of 35 parts by weight of potassium acetate and 15 parts by weight of distilled water into a 133 ml. polypropylene cup, having an inside diameter of 6.5 cm at its mouth. An expanded polytetrafluoroethylene (PTFE) membrane having a minimum MVTR of approximately 85,000g/m²/24 hrs. as tested by the method described in US Patent No. 4,862,730 to Crosby and available from W. L. Gore & Associates, Inc. of Newark, Delaware, was heat sealed to the lip of the cup to create a taut, leakproof, microporous barrier containing the solution.

A similar expanded PTFE membrane was mounted to the surface of a water bath. The water bath assembly was controlled at 23°C plus or minus 0.2°C, utilising a temperature controlled room and a water circulating bath. The sample to be tested was allowed to condition at a temperature of 23°C and a relative humidity of 50% prior to performing the test procedure. Three samples were placed so that each sample to be tested was in contact with the expanded PTFE membrane mounted over the surface of the water bath, and was allowed to equilibrate for at least 15 minutes prior to the introduction of the cup assembly.

The cup assembly was weighed to the nearest 1/1000g and was inverted onto the centre of the text sample.

Water transport was provided by the driving force between the water in the water bath and the saturated salt solution providing water flux by diffusion in that direction. The sample was tested for 20 minutes and the cup assembly was then removed, and weighed again to within 0.001g.

The MVTR of the sample was calculated from the weight gain of the cup assembly and was expressed in grams of water per square meter of sample surface area per 24 hours.

ABRASION TEST

Abrasion testing was carried out using a Martindale Abrasion machine and by rubbing samples with a standard wool toll SM25 which complied with draft ISO ST CD 12974-1 Table 1, clause 5.6.2 which is based on British Standard BS 5690, 1991.

Briefly, the test procedure is as follows:

Circular specimens of sample material are abraded on a reference abradant of a cross-breed worsted spun plain-woven wool fabric under pressure of 12kPa with a cyclic planar motion in the form of a Lissajous figure, which is the resultant of two simple harmonic motions at right angles to each other. The resistance to abrasion corresponds to the number of cycles to the defined end point. The abrasion machine is of the type described by Martindale (J.Text.Inst. 1942:33,T151).

Each sample is removed from the machine after a predetermined number of rubs and tested for liquid water-resistance as described herein (under a hydrostatic pressure of 2 psi (0.14 kg/cm²) for 3 minutes) until a leak was detected which indicated breakdown of water-resistance. Samples were tested every 100 rubs up to a 1000 rubs. They were then tested at the following intervals:

Every 2,000 rubs up to 20,000 rubs

Then every 5,000 " " 50,000 "

Then " 10,000 " " 100,000 "
and then " 20,000 ".

TEST FOR WATER-RESISTANCE (SUTER TEST)

Samples of the present invention were tested for water-resistance using a modified Suter test apparatus, which is a low water entry pressure challenge. The test procedure is set out in BS3424, method 29C. Water was forced against the underside of a sample of 11.25 cm diameter sealed by two circular rubber gaskets in a clamped arrangement. A sample having a substrate of expended PTFE with a hydrophilic coating on one side was mounted with the hydrophilic coating downwards against the water, the expanded porous PTFE membrane being uppermost. It is important that a leakproof seal is formed by the clamp mechanism, gaskets and sample. In deformable samples, the sample was overlaid by a reinforcing scrim (e.g. an open non-woven fabric) clamped over the sample. The upper side of the sample was open to the atmosphere and visible to the operator. The water pressure on the underside of the sample was increased to 2 pounds per square inch (0.14 kg/cm²) by a pump connected to a water reservoir, as indicated by a pressure gauge and regulated by an in-line valve. The upper side of the sample was visually observed for a period of three minutes for the appearance of any water which might be forced through the sample in the event of lack of water-resistance. Liquid water seen on the surface was interpreted as a deficiency in the water-resistance of the sample (i.e. a leak). The sample passed the test if no liquid water was visible on the upper side of the sample within the three minute test period.

The term "garment" includes jackets, trousers, overcoats etc.

An embodiment of the present invention will now be described by way of example only in conjunction with the attached drawings, wherein;

Figure 1 is a view of a garment i.e. a jacket, according to the present invention, and

Figure 2 is a schematic cross-sectional view of the outer shell and inner liner construction.

Figure 1 shows a jacket according to the present invention comprising an inner liner 2 and an outer shell 4 removably attached thereto. Both the inner liner and outer shell are full garments i.e. they cover both the body and arms of the wearer.

The inner liner is attached to the outer shell by means of half-zips 6,8 respectively down the front of the inner liner and outer shell, which are removably connected by means of a zip clasp 9. One complete zip is provided along each side of the front opening of the jacket.

The jacket is shown with the zip partially open to reveal a portion 10 of the inner liner, which is a first side of the water-resistant water-vapour-permeable material, and on which is provided the discontinuous pattern of abrasion-resisting polymeric dots.

Figure 2 shows a detailed cross-section of the inner liner 2 and the outer shell 4.

Suitable fabrics for the outer shell 4 include filament, staple or blends thereof of any suitable fibre including acrylics, polyesters, polypropylenes, nylons, aramids and melamines. They may be knitted, woven, non-wovens, impregnated fabrics or porous coated fabrics. Generally, the fabric has a moisture vapour permeability (MVTR) in the range 4000 to 19000 g/m²/24hr.

A preferred material for the outer shell is a 65% polyester, 35% cotton blend woven fabric, twill weave (weight 300 g/m²) treated with a water repellant finish (MVTR 19000 g/m²/24hr).

The inner liner 2 comprises an expanded polytetrafluoroethylene membrane 20 of the type disclosed in patent specification US 3,953,566 having applied thereto a coating 22 comprising a hydrophilic polymer as described in patent specification US 4,194,041.

The ePTFE layer 20 and the hydrophilic polymer coating 22 constitute the water-resistant water-vapour-permeable material of the inner liner. On a first side 24 thereof is applied a pattern of polymeric abrasion-resisting dots 26. The dots are applied in a rosette pattern. Each dot is in the shape of a truncated square pyramid of diameter approximately 780 microns and height 200 microns. Coverage is typically 60%. The composite inner liner laminate may be made by the coating and lamination techniques described in GB2316341. The abrasion-resisting polymer is a polyurethane polymer referred to as OLC-5T prepared according to Example 1 of patent specification US 5,209,969. Silicone polymer could also be used.

Both the hydrophilic coating 22 and optionally the polymeric abrasion-resisting dots comprise a filler consisting of nanometer size carbon particles.

Laminated to the inner face of the inner liner is a textile material which is aesthetically pleasing and may be any woven, knitted or non-woven material of any fibre type including nylons, aramids, melamines, acrylics. Typically, the textile lining 30 is a 100% polyester warp knitted, sueded material of a mass approximately 110 g/m².

Generally, the inner liner has an overall moisture vapour permeability in the region 3,000 g/m²/24hr to 14,000 g/m²/24hr.

The breathability of the garment as a whole (outer shell and inner liner) is greater than 2600 g/m²/24hr.

The abrasion resistance of the first side of the liner having the abrasion-resisting dot pattern was tested against 12 kPa abradent wool, and no leaks (6,895 kPa (1 psi) for 3 mins) were detected after 105,000 rubs. Tested against 12 kPa 65% polyester/35% cotton blend fabric, no leaks (6,895 kPa (1 psi) for 3 mins) were detected after 20,000 rubs, and in fact the fabric abraded away first.

A further benefit of this construction is that seam sealing of the sewn seams of the inner liner is carried out over the first side of the inner liner i.e. over the polymeric dot pattern. Thus, the seam sealing tape is not visible on the inside of the garment but is hidden by the presence of the outer shell.

Claims

A garment which comprises:

an outer shell (4) surrounding an inner liner (2);

the inner liner comprising a water-resistant water-vapour-permeable material having a first side and a second side; the first side facing the outer shell, the water-resistant water-vapour-permeable material comprising a substrate (20) coated with a hydrophilic film (22), and a discontinuous pattern of abrasion-resisting polymeric material being provided over said first side; the discontinuous pattern of abrasion-resisting polymeric. material being in the form of dots (26) characterized in that said dots (26) a height of 50 to 500 microns and said hydrophilic coating forms the first side (24).
A garment according to claim 1, which further comprises attachment means (6,8) for removably attaching the outer shell to the inner liner.
A garment according to any preceding claim wherein the water-resistant water-vapour-permeable material comprises an expanded polytetrafluoroethylene substrate (20) coated with said hydrophilic film (22).
A garment according to any preceding claim wherein the dots (26) are hemispherical in three-dimensional shape.
A garment according to claim 1-3, wherein each dot (26) approximates a truncated square pyramid.
A garment according to claim 5 wherein each dot (26) has a maximum diameter of 500 to 1000 microns.
A garment according to claim 5 or 6 wherein each dot (26) has a height of 100 to 400 microns.
A garment according to claim 5, 6 or 7 wherein the abrasion-resisting material covers 50 to 70% of the first side of the inner liner material.
A garment according to any preceding claim wherein the abrasion-resisting polymeric material is a polyurethane.
An inner liner (2) for a garment, which is formed of a water-resistant water-vapour-permeable material having a first side and a second side; the water-resistant water-vapour-permeable material comprising a substrate (20) coated with a hydrophilic film (22) forming the first side (24), a discontinuous pattern of abrasion-resisting polymeric material being provided over the first side; the discontinuous pattern of abrasion-resisting polymeric material being in the form of dots (26) having a height of 50 to 500 microns and which comprises attachment means for removably attaching the inner liner to an outer garment shell such that said first side having the pattern of abrasion-resisting polymeric material faces the outer garment shell.