GB2081721A - Porous drawn polyurethane blended polymer films - Google Patents

Porous drawn polyurethane blended polymer films Download PDF

Info

Publication number
GB2081721A
GB2081721A GB8124250A GB8124250A GB2081721A GB 2081721 A GB2081721 A GB 2081721A GB 8124250 A GB8124250 A GB 8124250A GB 8124250 A GB8124250 A GB 8124250A GB 2081721 A GB2081721 A GB 2081721A
Authority
GB
United Kingdom
Prior art keywords
film
polyurethane
films
polymer
moisture vapour
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB8124250A
Other versions
GB2081721B (en
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Smith and Nephew PLC
Original Assignee
Smith and Nephew Associated Companies PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Smith and Nephew Associated Companies PLC filed Critical Smith and Nephew Associated Companies PLC
Publication of GB2081721A publication Critical patent/GB2081721A/en
Application granted granted Critical
Publication of GB2081721B publication Critical patent/GB2081721B/en
Expired legal-status Critical Current

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
    • A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
    • A61L15/22—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons containing macromolecular materials
    • A61L15/225—Mixtures of macromolecular compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L75/00—Compositions of polyureas or polyurethanes; Compositions of derivatives of such polymers
    • C08L75/04—Polyurethanes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/249921—Web or sheet containing structurally defined element or component
    • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
    • Y10T428/249978—Voids specified as micro
    • Y10T428/249979—Specified thickness of void-containing component [absolute or relative] or numerical cell dimension
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/249921—Web or sheet containing structurally defined element or component
    • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
    • Y10T428/249982—With component specified as adhesive or bonding agent
    • Y10T428/249983—As outermost component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/249921—Web or sheet containing structurally defined element or component
    • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
    • Y10T428/249982—With component specified as adhesive or bonding agent
    • Y10T428/249985—Composition of adhesive or bonding component specified
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/26—Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
    • Y10T428/268—Monolayer with structurally defined element
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/28—Web or sheet containing structurally defined element or component and having an adhesive outermost layer

Abstract

A moisture vapour transmitting film comprising a blend of polyurethane and an incompatible polymer characterised in that the incompatible polymer forms a discrete phase within a continuous matrix of polyurethane and that said film contains voids and processes for the manufacture thereof.

Description

1 GB 2 081 721 A 1
SPECIFICATION Polymer blend films, their preparation and use
The present invention is concerned with moisture vapour transmitting polymer blend films, methods of manufacture and their use.
Moisture vapour transmitting polyurethane films are known and their use as backings in adhesive 5 dressings is disclosed in British Patent Specification No. 1,280,361. This patent discloses that suitable polyurethane films are 25 microns thick and can have a moisture vapour transmission rate of approximately 1 600g/m2/24 hours at 370C at 100% to 10% relative humidity difference.
Such thin polyurethane films are very flexible and conformable to skin but are difficult to handle especially when coated with adhesive. Polyurethane films of suitable thickness to enable them to be 10 handled have much lower moisture vapour transmission rates. A method of making porous polyurethane films by permanently stretching thermoformed polyurethane films containing large amounts of inorganic filler is disclosed in US Specifications Nos. 3,844,865 and 3,870,593. However, it is also disclosed in the US specifications that the porous films have physical properties similar to
1!. paper and that water and aqueous solutions can permeate these films. British Patent Specification 15
No. 1,226,841 discloses porous films of a blend of polyurethane and polyvinyl chloride.
It would be advantageous to have a moisture vapour transmitting polyureihd-he film of a handleable thickness which is impermeable to liquid water and capable of being a barrier to bacteria in bandages and dressings.
Elastomeric moisture vapour transmitting polyurethane blend film suitable for bandages and 20 dressings have now been discovered which are impermeable to liquid water.
The present invention provides a moisture vapour transmitting elastomeric films comprising a blend of polyurethane and in incompatible polymer characterised in that the incompatible polymer forms a discrete particulate phase within a continuous matrix of polyurethane and that said film contains voids.
The term "voids when used herein means small holes within the film. These small holes may interrupt the surface or may coalesce. The voids normally have a diameter from.2 to 11 2 microns, for example 3 to 6 microns. Voided films of this invention are impermeable to liquid water and therefor do not contain openings or passages which provide a continuous pathway through the film.
In a second aspect this invention provides a moisture vapour transmitting elastomeric film 30 comprising a blend of polyurethane and a discrete particulate phase characterised in that the discrete particulate phase comprises an incompatible polymer and that said film contains voids.
Suitable polyurethanes for use in this invention are those which can be formed into an elastomeric film.
Especially suitable are the class of polyurethanes which are known as thermoplastic polyurethanes. Aptly the polyurethane employed is a linear polyester or polyether polyurethane.
Preferred are linear thermoplastic polyurethanes known as Estanes (Trade Mark) made by B. F. Goodrich and Co. Ltd., which are a range of linear olyester and polyether urethanes. A preferred polyurethane of this type is Estane 580201 which is an extrusion grade linear polyether urethane.
Other suitable linear thermoplastic polyurethanes include Estane 5714, Pellethane 21103-8AE 40 (Trade Mark) available from Upjohn and Elastollan L85-Al 0 and P85-M 10 (Trade Marks) available from Elastogran (U.K.) Limited.
The polyurethane can contain additives such as fillers and antioxidants.
It is preferred that th( particles of the discrete particulate phase of incompatible polymer should be spherical or ellipsoidal in shape and have a diameter of at feast 1 micron, for example 2 microns to 5 45 microns.
Suitable incompatible polymers include those derived from polymerisation of vinyl hydrocarbons, for example polyethylene and polystyrene.
It is desirable that mechanical and physical properties of the incompatible polymer are significantly different from that of the polyurethane at temperatures at which the film will cold draw. 50 It is particularly desirable that the incompatible polymer should have a higher modulus than that of the polyurethane at the cold draw temperatures.
It is also desirable that the incompatible polymer has a lower melt viscosity than the polyurethane at its melt forming temperature.
In this respect it is often advantageous for the incompatible polymer to contain a filler such as a 55 reinforcing filler. It follows that certain preferred films of this invention include these in which the incompatible polymer contains a filler such as an inorganic filler. Such fillers are frequently present by 4 to 15%, for example 10 to 12%. A particularly apt filler is calcium carbonate.
An especially suitable incompatible polymer is low density polyethylene containing a filler.
Another especially suitable incompatible polymer is polystyrene. The polystrene may be an 60 unmodified (homopolymer) or rubber modified grade. High impact polystyrene is a preferred incompatible polymer.
The incompatible polymer can advantageously contain a lubricant. Suitable lubricants include fatty acids and their amide and ester derivatives, such as stearamide and glyceryl monostearate. Suitably the 2 GB 2 081 721 A 2 lubricant may be present in amounts up to 10% by weight but preferably in amounts not more than 5% by weight of the incompatible polymer. a favoured low density polyethyiene contains 5% by weight of stearamide.
A preferred low density polyethylene is a purging composition reference DG 0964 supplied by British Petroleum. The composition consists essentially of a low density polyethylene containing about 5 11 % parts by weight of a filler consisting.mainly of silica with small amounts of calcium carbonate and small amounts of glycery] monostearate, stearamide and a phenolic antioxidant.
A preferred polystyrene is a high impact polystyrene reference 6MW supplied by R. H. Cole Ltd.
The proportions of polyurethane and the incompatible polymer in the blend depend on some extent on the individual polymers. However in general suitable blends contain 40% to 90% by weight, 10 desirably 45% to 85% by weight and preferably 50% to 80% by weight of polyurethane.
One preferred blend contains 60% of a polyurethane (for example 60% by weight of Estane 5820 1) and 40% by weight of incompatible polymer for example low density polyethylene purging compound from British Petroleum. Another preferred blend contains 80% by weight of polyurethane (for example Estane 58201) and 20Yo by weight of high impact grade polystyrene reference 6MW from R. H. 15 Cole Ltd. A further preferred blend contains 60% by weight of polyurethane and 40% by weight of high impact polystyrene.
The film of the invention can. be used as a backing film for medical dressings and bandages such as adhesive coated first aid dressings and compression bandages. For these uses it is preferred that the film has a moisture vapour transmission rate of at least 200g/M2 more suitably at least 350g/M2, preferabl y at least 500g/m2 and most preferably at least 1 000g/m2 at 100%-10% relative humidity difference.
Most aptly the film of this invention is used as the backing in an adhesive dressing suchas a first aid dressing. Such dressings form a part of this invention.
It is preferred that adhesive coated medical dressings have a moisture vapour transmission rate of at least 1 50g/mI, suitably at least 2509/M2 and preferably at least 500g/m2 at 371C at 100%-10% relative humidity difference. - The adhesive coating layer can be discontinuous for example in the form of porous (including microporous) or pattern coated layers. However it is preferred that the adhesive coating layer is continuous.
Suitable continuous adhesive layers can comprise an acrylate ester copolymer or a polyvinyl ether.
Preferred acryiate ester copolymer adhesives are disclosed in United Kingdom Application No.
8106701. A favoured acrylate ester copolymer of, 47 parts by weight of 2ethyihexyl acrylate, 47 parts by weight of n-butyl acrylate and 6 parts by weight of acrylic acid.
Suitably the thickness of the adhesive layer of adhesive dressings of the invention can be from 35 12.5 microns to 75 microns. Suitable thickness of the film backings of adhesive dressings of the invention are described hereinafter-in relation to films of the invention.
The dressings of this invention will no ' rmally contain a pad covered with a non-adherent wound facing layer as is conventional in dressings of this type.
The moisture vapour transmission rate may be measured by the Payne Cup method. The method 40 - uses a cup 1.5cm deep with a flanged top. The inner diameter of the flange is such to provide an area for moisture vapour transmission of 1 OCM2. In this method 1 Omi. of distilled water is added to the cup and a sample of the material under test, large enough to completely cover the flange, Is clamped over the cup. The complete assembly is then. weighed and placed in a cabinet where the temperature and relative humidity are maintained at 3.IC and 10% respectively. After 17 hours the cup is removed from 45 the cabinet and allowed to cool at room temperature. After re-weighing, the mass of water lost by vapour transmission is calaculated and the result expressed as in g/m2/24hrs. at 371C at 100% 1 10% relative humidity difference.
It is suitable that the film of this invention has a thickness of 0.01 25mm to 0.25mm more suitable 0.05mm to 0.25mm, desirably 0.01 25mm to 0.125mm and preferably 0.075mm to 0.125mm. 50 It is desirable that the film of this..invention has a recoverable elastic strain of at least 100%, more suitably at least 150% and preferablyat least 200%.
The film of the invention is normally opaque due to the voids in the body of the film.
The films of the invention have a. soft surface feel when they are used in the manufacture of body 7 f 1.
contact articles.
The invention provides a process for making a film of this invention which comprises forming a film from a blend of polyurethane and an incompatible polymer and cold drawing (that is stretching at to 45IC) the film until voiding occurs and thereafter allowing the drawn film to contract.
It is preferred that the film is formed by hot melt process in particular by hot melt extrusion. Lt is also preferred that the blending of the polyurethane and the incompatible polymer is carried out under 60 hot melt conditions although pre-mixing of the granules can be carried out by tumbling at room temperature.
Figure 1 illustrates a process for the manufacture of film of this invention.
Premixed granules of polymers are fed into extruder 1 via hopper 2 and extruded as hot melt film 3 which is fed downwards between the nip of the casting rollers 4 to form the polymer blend film 5. The 65 1 il 1 3 GB 2 081 721 A 3 polymer blend film 5 is fed into stenter 6 where it is stretched to give a voided film. The stenter 6 can be of a type which can be operated in different ways to give the necessary longitudinal and/or transverse stretch. In an alternative process the polymer blend film can be made by blown film extrusion.
The extruded polyurethane and incompatible polymer blend film can be stretched to form the elastomeric film containing voids. The stretching should be carried out at cold draw temperatures for example 1 OIC-450C preferably at 1 51C-301C. The stretching can take place in longitudinal or transverse to the extrusion direction. It is preferred that the film is stretched in the transverse direction. It is preferred that the film should be given a stretch of between 200% to 500%. The degree of stretching should be greater than the yield elongation but less than the elongation at break of the film at cold draw temperatures.
After stretching the film is also allowed to contract. These stretching and relaxation stages convert the polyurethane-incompatible blend films into an elastomeric film containing. voids. These voids are normally very small.. with diameters of between 2 and 12. microns and more usually between 3 and 6 microns.
The dressing of this invention may be prepared from the film of this invention in conventional 15.
manner, for example on conventional dressing machines.
EXAMPLE 1 parts by weight of Estane 58201 granules and 40 parts by weight of low density polyethylene purge compound from British Petroleum Limited was premixed by tumbling. The mixed granules were fed into a 60mm Reifenhauser extruder with a length to diameter screw ratio of 20:1 and a compression 20 ratio of 3:1 having a barrel temperature gradient of 1 651C to 1850C at the die end, and the hot melt polymer blend extruded through a 60Omm slit film die at a rate of 5 metres/min. The molten film was fed between the nip, of chill rollers maintained at a temperature of 701C and the cooled film wound up.
The extruded film was 45Omm wide. and 0.0875mm thick.
The film was given a transverse stretch of 500% and then allowed to contract to 200% of its initial 25 width. The film properties were as-follows:
as. extruded after stretching Thickness (mm) 0.0875 0.06 Moisture Vapour Transmission 200 643 rate (glml/24 hrs at 37C at 100% " 10% R.H.% difference EXAM P LE 2 parts by weight of Estane 58201 and 20 parts by weight of high impact polystyrene ref. 6MW from R. H. Cole Ltd. were premixed by tumbling and extruding as Example 1 to form a film 45Omm wide 30 and 0. 1 m m thick.
(a) The film was stretched by 500% in the transverse direction and allowed to contract to 200% of its initial width.
(b) The film was stretched by 500% in the lengthwise direction and allowed to contract to 200% of its initial length. The films had the following properties: 35 after stretching as extruded a b Thickness (mm) 0.1 0.067 0.064 Moisture Vapour 873 773 Transmission Rate (g/M2/24 hrs at 370C at 100% - 10% R.H. difference EXAMPLES 3 to 17 Production of Voided Film The effect of the processing conditions on the properties of voided films made from polymer blends of polyurethane (PLI) reference Estane 58201 and high impact polystyrene (HIPS) reference 40 6MW (from R. H. Cole Limited) or PU and a low density polyethylene (purge) reference DG 0964 (from B.P. Chemicals Limited) are illustrated by Examples 3 to 17.
The voided films of Examples 3 to 17 were made by extruding a polymer mixture as a hot melt through a flat film die into a cooled two roller casting unit and stretching the resultant film on a laboratory tensometer in the following manner.
4 GB 2 081 721 A 4 Polymer Mixture Preparation a) Granules of the polyurethane and the incompatible polymer were mixed by tumbling.
b) The mixture was then fed into a Reifenhauser S60 extruder (melt temperature 1 901C, screw speed 38 rpm) and formed into filaments 1 mm to 2mrn in diameter.
a) The filaments were then cut into 3mm to 5mm lengths.
d) The polymer prepared was then dried in an air circulating oven at 900C for 4 hours using 2.5 cm deep trays. (in example 3 steps b) and c) were omitted).
Extrusion Conditions Films-we-re -made byleeding the polymer mixture into a 37 5mm extruder (Johnson Spartan 150, 10 length to diameter screw ratio of'24-1) -and extruding the polymer mixture at a melt temperature of 1901 C through a 30Omm flat film die into the nip of a cooled two roller film casting unit located 7.5cm directly below the die (rollers maintained at 401C and 30IC).
Q Stretching Conditions The voided films were made by stretching samples of the cast films in the machine direction (M) or 15 transverse direction (T) on a laboratory Hounsfield tensometer. The film samples had a gauge length of 5Omm ond an aspect ratio of 0.5. Samples were stretched to a. draw ratio of 5:1 (400% extension) at rates of between 50mm/min and 125mm/min at 20C and 251'C. The drawn films were then allowed to contract.
0 Results The properties of the thus produced films are given in Table 1. The moisture vapour transmission rate (MVTR) was calculated by the Payne Cup method and the load required-to produce 100% strain (Load/1 00% strain) was calculated from a load/elongation curve derived using sainples with a gauge length of 2.54cm and a width of 2.54cm measured parallel to the draw direction. - The result show that the WTR of the voided films is greater than that of films of similar thickness 25 composed of polyrethane alone (cf Estane 58021 WTR of about 4509/m/24hrs. /37.C/l'OOV,1 0% RH difference for 0. 1 mm film). The load/1 00% strain figures demonstrate that conditions may be varied in order to produce films with various stiffnesses.
1 ,,.'I TABLE 1
Processing Conditions Thickness Composition Die Screw Casting Weight of Load/100% parts by weight Nip Example Gap Speed Speed Draw Initial Final Final Drawn MVTR strain (%) Draw Film (kg/2.5 cm No. (MM) (rpm) (m/min) Dirn. (mm) Ratio (g/M1 (g/m'124 br) wi dth) PU HIPS Purge 3 0.305 22.5 4.0 m 0.102 0.046 3.04 39 1079 2.93 60 40 4 0.305 37.5 2.0 T 0.305 0.229 1.92 121 579 1.41 60 40 0.305 50.0 6.0 T 0.147 0.104 - 91 574 1.35 60 40 6 0.305 50.0 8.0 m 0.106 0.041 3.20 36 637 4.07 60 40 7 0.153 22.5 4.0 T 0.074. 0.056 1.70 51 1612 0.68 60 40 8 0.305 22.5 2.0 m 0.157 0.114 2.58 49 1533 1.34 50 so 9 0.153 22.5 2.0 m 0.140 0.099 2.30 87 1011 2.08 60 40 0.153 22.5 2.0 T 0.140 0.112 1.80 99 1115 1.09 60 40 11 0.153 22.5 2.0 m 0.132 0.097 2.46 75 1432 2.30 50 50 12 0.153 10.0 2.0 m 0.119 0.106 2.24 49 2430 0.57 50 - 50 13 0.153 22.5 2.0 T 0.216 0.201 2.38 92 2432 0.67 50 - 50 14 0.153 37.5 2.0 T 0.236 0.229 2.54 175 2060 1.20 50 - 50 0.305 22.5 2.0 m 0.152 0.135 2.30 - 3031 - 45 - 55 16 0.305 37.5 2.0 T 0.234 0.208 2367 - 55 17 0.305 22.5 2.0 T 0.142 0.129 1.90 2072 50 - 50 M G) W hi 0 00 L A GB 2 081 721 A 6 EXAMPLES 18 to 27 Preparation of VoidedFilm Examples 18 to 27 show the effect of varying the draw ratio in machine and transverse directions (including biaxial stretching) on the properties of voided films made from 60/40 polymer blends of polyurethane (PLI) reference Estane 58201 and high impact polystyrene (HIPS) reference 6 MW from R.
H. Cole Limited and 59/40 blends of PU and HIPS also containing 1 part by weight of Brown Pigment reference 15.075 from Anstead Limited.
Voided films of Examples 18 to 28 were prepared in a similar manner to that of Examples 3 to 17 exceptthat:
a) at polymer mixture stage in blends containing a pigment the pigment was predispersed into the 10 polyurethane granules; b) at the extrusion stage the films were made by feeding-the polymer mixture into a Reinfenhauser 560, 60mm extruder (length to diameter screw ratio of 20:1) and extruding the polymer blend (screw speed 20 rpm) at a melt temperature of 1900C through a 60Omm flat film die set at a gap of 0.254mm, into the nip of a cooled two roller (rollers maintained at 401C and 3WC) film casting unit located T5 13.75cm directly below the die and rotating at 3.2 metres/min and c) at the drawing stage the gauge length of the test samples were 1 0Omm and the aspect ratios and the draw ratios were varied.
The castfilms of Examples 18, 19, 20, 23, 24 and 25 were sequentially drawn in the transverse direction and then in the machine direction. The drawn films were allowed to contract after each draw 20 as in Examples 3 to 17.
Results The MYrR and load at 100% strain was calculated as in Examples 3 to 17. The tear resistance of the voided films were measured parallel to the final draw direction (by the -Trouser Leg- tear method of ASTM D 1938 using a 0. 1 25mm slit and a separation speed of 20Omm/minute.
The results set forth in table 2 demonstrate that MVTR of biaxially drawn film increases over that of uniaxially drawn films. The results also demonstrate that biaxially drawn films exhibit an increased tear resistance when compared with films stretched in the machine direction only. (The greatest tear resistance can be obtained by stretching in the transverse direction only; and that transverse stretching maybe used to enhance the mechanical orthotropy of the film.
f i z 7f 11). ', TABLE 2
Load/100% strain Final Final Final Final MVTR Width g/2.5cm Tear 1st. Draw Aspect 2nd. Draw Aspect Thickness Weight (g/M21 Resistance Film Example
No. Draw Rat! o Ratio Draw Ratio Ratio (mm) Osm) 24 hr.) (a) (b) (9) Composition 18 2:1 T 1.15 0.67 5:1M 2.53 0.46 0.099 87 829 2196 721 16 1 19 3:1 T 1.40 5: 1M 2.34 0.41 0.103 84 908 1960 709 18.9 4:1 T 1.70 5:1M 2.40 0.J7 0.095 73 1123 1646 577 17:0.60:40 PUMIPS 21 5:1T - 0.50 0.107 91 750 1263 1182 144 9 22 5:1M - 1 1 3 - - - 0.103 85 661 2235 603 9.3 0.6 23 2:1 T 1.12 0.67 5:1M 2.68 0.45 0.111 95 859 3163 -908 14.6 1.9 24 3: 1T 1.32 5: 1M 2.68 0.38 0.104 88 10961 2713 712 15.5 0.2 4:1T 1.60 5: 1M 2.68 0.31 0.100 80 1251 2285 609 14.1 G.5 50:11:40 P i gment 26 5:1T 1.86 0.50 0.126 114 661 1775 1425 84.7 8.6 HIPS 27 S: 1M 2.60 0.107 95 2526 854 854 17.0 1.9 (a) measured parallel to final draw direction.
(b) measured perpendicular to final draw direction.
G) m N 0 00 -j 1 8 GB 2 081 721 A 8 EXAMPLE 28 Preparation of Voided Film Cast film made by the method-of Example 18 was stretched on a tensil - e test machine (Instron 1195) inside a specially constructed dilatometer. The samples used had a thickness 0.1 52mm, a gauge length of 40mm and an aspect ration of 0.67. The draw rate was 50mm/min. at approximately 2011C maximum extension was 4.75A. The voided film had a thickness of 0.1 14mrn at a final (relaxed draw ratio of 2.05 and a moisture vapour transmission rate of 808 g/m2/24 hours at 371C at 100% to 10% relative humidity difference. Dilatometer measurements- indicated that the drawn film had increased its volume by 45% at a maximum extension (375%) and by 15% after it had been allowed to relax.
EXAMPLES 29 to 34 Examples 29 to 34 show the effect of using different thermoplastic polyurethanes in 60/40 blends of polyurethane and high impact polystyrene reference 6 MW on the moisture vapour transmitting properties of the voided films.
Voided films of Examples 29 to 34 were prepared in the same manner as Examples 9 or 10.
The MVTR of the voided films were calculated as described in Examples 3 to 17 and are set out in 11.5 Table 3. These results demonstrate that high MVT11 values can be obtained using polyester polyurethanes as well as with polyether polyurethanes.
z R 11 -1 ' 1 11., ' # TABLE 3
Initial Final Example Thickness Wei ght Thickness Weight MVTR No. (M0 (g) (mm) (g) gIml/24 hr. Composition 29 M 0.175 190 0.125 104 1135 Estane 5714F (A Oolyether polyurethane) M 0.158 170 0.110 94 1490 Pellethane 2103-BAE (A polyether polyurethane) 31 T 0.158 170 0.110 93 1685 Pellethane 2103-8AE (A polyeth'er polyurethane) 32 M 0.165 174 0.113 89 1460 Elastollan C85 A10 JA polyester polyurethane) 33 M 0.190 203 0.130 110 1460 Elasto I lan.PB5 A10 (A polyether polyurethane) 34 T 0.185 206 0.150 121 1050 (D N W i GB 2 081 721 A 10 EXAMPLES 35 to 340 Production of Voided Film The unpigmented voided films were made Uy stretching 40Omm wide cast film prepared in the same manner as for Examples 18 to 22 except that in Example 36 the polymer mixture steps (b) and (c) were omitted. The pigmenteo voided films were made by stretching 40Omm cast film prepared in the 5 same manner as for Examples 23 to 27 except that in Examples 38 and 39 the pigment was dispersed in the high impact polystyrene (HIPS) phase instead of the polyurethane phase (PU).
The voided films of Examples 35 to 50 were prepared by passing the cast films through a Kampf stretcher at ambient room temperature whichresulted in the cast films being cold drawn in the machine direction. The cast film used in Example 40 was given a transverse stretch in a stenter before being 10 passed into the Kampf stretcher so that the resulting voiddd film was drawn biaxially. The film were allowed to contract after each draw.
The results set out in Table 4-were obtained using the methods of Examples 18 to 27 and show Jarger scale manufacture produces films of sirnilar properties.to those of smailer scale manufacture.
The voided films of Examples 35 to 40 were subjected to a hydrostatic pressure test in which a V5 - sample film supported a filter paper is subjected to the pressure exerted by a 1 50cm column of a water/detergent mixture (contains 1 % by weight of Teepol). After 90 minutes no penetration of the films was observed indicating that the films were impermeable to liquid water (cf, microporous polyvinylchloride film which at 250 microns fails to support a 80cm column of aqueous detergent).
t i It '.1.1 1 1). p 1.
TABLE 4
Example Film Composition % by wt. Final Final Tear No. PU HIPS. Pigment stretching Thickness Weight MVTR (g).
Details (MM) (g/M2) (g/M2/24hr.
60 40 5:1 MID 0.073 75 1000 9.9 36 60 40 5:1 MID 0.08 72 570 7.7 37.59 40 1 5:1 MID 0.08 63 1130.6.0 38 60 391 1 4'75:1 MD 0.083 68 790 '9 4 39 60 37.5 2.5 4.25:1 MD 0.1 90 620 14.6 60 40 11' TD, 0.1 89 770 21.1 4:1 MG N 12 - - - 0, - - GB 2 081 721 A - 12 EXAMPLES 41 to 43 Preparation ofA dhesive Dressings Voided films of Examples 35,47 and 40 were coaied with a pressure sensitive adhesive composition consisting of a copolymer of 47 parts by weight of 2-ethy-1 hexyl acrylate, 47 parts by weight of n-butyl acrylate and 6 parts by weight of acrylic acid polymerised in acetone according to 5 the general method of United Kingdom Application No. 8106707. A dry continuous layer of adhesive at a coating weight of 28g/M2 was obtained.
Exampt e WTR No. Film (gl.M2/24hr.) 41 Ex. 35 650 42 Ex. 37. 670 43 Ex. 40 680 The adhesive coated films of Examples 37 and 40 were converted on a standard dressing machine into first aid dressings and Examples 3 5 converted on a standard dressing machine into 7.5cm x 5cm 10 wound dressing and into larger ward and theatre dressings. The dressings were found to conform well to the skin when applied to the hands of volunteers.
EXAMPLES 44 and 45 Production of VoldedFilms 15 Examples 44 and 45 illustrate the production of voided films from polymer blend films made by a 15 tubular blown film extrusion process. A polymer mixture of 60 parts by weight of polyurethane (Estane 58201) and 40 parts by weight of high impact polystyrene (reference 6MW from R. H. Cole Limited) was prepared in the same manner as for Examples 3 to 17. 20 The films were made by feeding the polymer mixture into a Brabender 1 9mm 25L/D extruder fitted with a standard polyolefin type screw (4:1 compression ratio) and extruding the polymer mixture (screw speed 120 revs/minute) at a melt temperature of 110911C through, a tubular film die (diameter 2.54cm, die gap 0.5mm). The extruded tube was inflated by air pressure io a diameter of 6.5cm (blow ratio of 2.55:1) or a diameter of 4.Ocm (blow ratio of 1. 59:11). Voided films were made by stretching samples of the tubular film to a draw ratio of 5:1 in thb transverse direction in the same manner as Examples 3 to 17.
Results Moisture vapour transmission rates and load at 100% strain of voided films were calculated in the same manner as Examples 3 to 17. The tear resistance of the voided films was measured parallel to the final draw direction as in examples 18to 27. - - The results set forth in Table 5 confirm the results already obtained for the cast flat films of Examples 18 to 27. In particAr they confirm that films stretched in the transverse direction only have good tear resistance and are more orth6tropic.
i Z.
t TABL.E 5 1,..
Exampi e Blow lnitial.Film Final Final MVTR Load/ 100% strain Tear Thickness Thickness Weight (g/2.5 em) No. Ratio (mm) (mm) (g/m) (g/M2/24hr.) MID TD (MD) (9) 44 2.55:1 0.1 0.95 55 861 1440 1150 160 1.59:1 0.1575 0.13 106 499 1850 2070 150 G) m r-i 14..
GB 2 081 721 A 14 EXAM P LE 46 P.reparation of VoidedFilms Parts by weight of low density polyethylene (Alkathene 17 from ICI Plastics Limited) and 5 parts by weight of stearamide (Crodamide SR from Croda Chemicals Limited) were uniformly mixed in a shearmix size 4 (Baker Perkins Limited) at a temperature of 1601C for 20 minutes. The mixture was 5 discharged into aheated two roller mill (1 251C) and formed into sheet which was subsequently granulated.
A premixture of polyurethane (60 parts by weight of Estane 58201) and the low density polyethylenelstearamide mixture (40 parts by weight) was prepared by tumbling the granules. A cast film was made by hot melt extrusion in the same manner as Example 4 and the voided film made by 10 stretching transverse to the extrusion direction in the same manner as Examples 3 to 17. The stretched film was allowed to contract. The initial film thickness was 0.255mm, the final film thickness was 0.1 5Omm and the final film weight per unit area was 101 g/M2.

Claims (20)

  1. CLAIMS:- is 1. A moisture vapour transmitting film comprising a blend of
    polyurethane and an incompatible polymer characterised in that the incompatible polymer forms a discrete particulate phase within a continuous matrix of polyurethane and that said film contains voids.
  2. 2. A moisture vapour transmitting elastomeric film comprising.a blend of polyurethane and a discrete particulate phase characterised in that the discrete particulate phase comprises an incompatible polymer and the film contains voids.
  3. 3. A film as claimed in either of claim 1 or 2 in which the voids have a diameter of 2 microns to 12 mocrons.
  4. 4. A film as claimed in any of claims 1 to 3 in which the film has a moisture vapour transmission rate of at least 350g/m2/24 hours at 371C at 100% to 10% relative humidity difference. -
  5. 5. A film as claimed in any of claims 1 to 4 in which the film has a thickness of 0.01 25cm to 25 0.125.
  6. 6. A film as claimed in any of claims 1 to 5 in which the polyurethane is a linear polyurethane.
  7. 7. A film as claimed in any of claims 1 to 5 in which the polyurethane is a linear polyester urethane.
  8. 8. A film as claimed in any of claims 1 to 7 in which the polyurethane comprises 50% to 80% by 30 weight of the film.
  9. 9. A film as claimed in any of claims 1 to 8 in which the incompatible polymer comprises a vinyl polymer.
  10. 10. A film as claimed in claim 9 in which theyinyl polymer comprises a polystyrene.
  11. 11. A film as claimed in any of claim 10 in which the polystyrene is a high impact polystyrene. 35
  12. 12. A film as claimed in claim 9 in which the vinyl polymer comprises polyethylene.
  13. 13, A film as claimed in claim 12 in which the polyethylene is a low density polyethylene containing inorganic filler.
  14. 14. A medical dressing which comprises a film as defined in any of claims 1 to 13.
  15. 15. A medical dressing as claimed In claim 14 coated with an adhesive.
  16. 16. A medical dressing as claimed in claim 15 which has a moisture vapour transmission rate of at least 250g/m2124 hours at 371C at 100% to 10% relative humidity difference.
    i L
  17. 17. A medical dressing as claimed in either claim.15 or 16 in which the adhesive layer is continuous.
  18. 18. A medical dressing as claimed in claim 17 in which the adhesive comprises an acrylate ester 45 copolymer.
  19. 19. A process of making a film as defined in any of claims 1 to 18 which comprises forming a film from a blend of polyurethane and an incompatible polymer, cold drawing the film until voiding occurs and thereafter allowing the drawn film to contract.
  20. 20. A process as claimed in claim 19 in which the film is formed by hot melt extrusion.
    2 1. A process as claimed in claim 19 in which the film is stretched in a direction transverse to the extrusion direction.
    Printed for Her Majesty's Stationery Office by the Courier Press, Leamington Spa, 1982. Published by the Patent Office, Southampton Buildings, London, WC2A lAY, from which copies may be obtained.
    i 50.
    If
GB8124250A 1980-08-13 1981-08-07 Porous drawn polyurethane blended polymer films Expired GB2081721B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB8026366 1980-08-13

Publications (2)

Publication Number Publication Date
GB2081721A true GB2081721A (en) 1982-02-24
GB2081721B GB2081721B (en) 1984-05-23

Family

ID=10515429

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8124250A Expired GB2081721B (en) 1980-08-13 1981-08-07 Porous drawn polyurethane blended polymer films

Country Status (12)

Country Link
US (1) US4452845A (en)
EP (1) EP0046071B1 (en)
JP (1) JPS5763229A (en)
AT (1) ATE6741T1 (en)
AU (1) AU545048B2 (en)
CA (1) CA1177208A (en)
DE (1) DE3162807D1 (en)
DK (1) DK168633B1 (en)
GB (1) GB2081721B (en)
IE (1) IE51473B1 (en)
NZ (1) NZ197988A (en)
ZA (1) ZA815523B (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0072258A2 (en) * 1981-08-12 1983-02-16 Smith and Nephew Associated Companies p.l.c. Adhesive dressing and components
US4596738A (en) * 1983-10-22 1986-06-24 Smith And Nephew Associated Companies P.L.C. Polymer blend films
US4605165A (en) * 1984-06-13 1986-08-12 International Flavors & Fragrances Inc. Constant rate volatile composition dispensing article and process for using same
US4614299A (en) * 1984-06-13 1986-09-30 International Flavors & Fragrances Inc. Article which dispenses at a constant rate a volatile composition, and process for using same
US6592995B2 (en) * 2001-07-24 2003-07-15 Kimberly-Clark Worldwide, Inc. Humidity activated materials having shape-memory
US6627673B2 (en) * 2001-07-24 2003-09-30 Kimberly-Clark Worldwide, Inc. Methods of making humidity activated materials having shape-memory
US6933421B2 (en) * 2001-07-24 2005-08-23 Kimberly-Clark Worldwide Inc. Methods of making disposable products having humidity activated materials with shape-memory

Families Citing this family (77)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IL65438A (en) * 1982-04-06 1984-12-31 Israel Atomic Energy Comm Synthetic wound covering
DE3361672D1 (en) * 1982-04-08 1986-02-13 Smith & Nephew Ass Surgical adhesive dressing
US4863778A (en) * 1982-04-24 1989-09-05 Smith And Nephew Associated Companies P.L.C. Products, processes and use
AU562370B2 (en) * 1982-10-02 1987-06-11 Smith & Nephew Associated Companies Plc Moisture vapour permeable adhesive surgical dressing
FR2542201B1 (en) * 1983-03-11 1985-07-26 Lhd Lab Hygiene Dietetique NOVEL SURGICAL SUPPORT COMPRISING A POLYURETHANE FILM AND A NON-WOVEN, USE IN PARTICULAR IN THE FIELD OF DRESSINGS, AND PREPARATION METHOD
GB8334484D0 (en) * 1983-12-24 1984-02-01 Smith & Nephew Ass Surgical dressing
GB2164653B (en) * 1984-09-21 1988-07-13 Nippon Paint Co Ltd Composite film and preparation thereof
US5153040A (en) * 1985-03-11 1992-10-06 Minnesota Mining And Manufacturing Co. Wound dressing
US4698372A (en) * 1985-09-09 1987-10-06 E. I. Du Pont De Nemours And Company Microporous polymeric films and process for their manufacture
US4704130A (en) * 1985-10-18 1987-11-03 Mitral Medical, International, Inc. Biocompatible microporous polymeric materials and methods of making same
US4829096A (en) * 1986-07-16 1989-05-09 Sumitomo Chemical Company, Limited Breathable film and process for production of the same
US5009224A (en) * 1986-09-30 1991-04-23 Minnesota Mining And Manufacturing Company Method for attaching a pressure-sensitive film article having high moisture vapor transmission rate
EP0262786B1 (en) * 1986-09-30 1994-10-12 Minnesota Mining And Manufacturing Company Pressure-sensitive adhesive film article having high moisture vapor transmission
US5147698A (en) * 1986-09-30 1992-09-15 Minnesota Mining And Manufacturing Company Pressure sensitive adhesive film article having high moisture vapor transmission rate
US4713069A (en) * 1986-10-31 1987-12-15 Kimberly-Clark Corporation Baffle having zoned water vapor permeability
US4713068A (en) * 1986-10-31 1987-12-15 Kimberly-Clark Corporation Breathable clothlike barrier having controlled structure defensive composite
US4758239A (en) * 1986-10-31 1988-07-19 Kimberly-Clark Corporation Breathable barrier
US4906463A (en) * 1986-12-22 1990-03-06 Cygnus Research Corporation Transdermal drug-delivery composition
AU607172B2 (en) * 1986-12-22 1991-02-28 Cygnus, Inc. Diffusion matrix for transdermal drug administration
US5006342A (en) * 1986-12-22 1991-04-09 Cygnus Corporation Resilient transdermal drug delivery device
US4913410A (en) * 1987-01-07 1990-04-03 Marshall Robert L Particle for vibration damping
US5593395A (en) * 1987-08-07 1997-01-14 Martz; Joel D. Vapor permeable dressing
US5061258A (en) * 1987-08-07 1991-10-29 Martz Joel D Vapor permeable dressing with releasable medication
US4890628A (en) * 1987-12-03 1990-01-02 Kimberly-Clark Corporation Surgical drape with means for channeling and collecting fluids
US4818600A (en) * 1987-12-09 1989-04-04 Kimberly-Clark Corporation Latex coated breathable barrier
US5252334A (en) * 1989-09-08 1993-10-12 Cygnus Therapeutic Systems Solid matrix system for transdermal drug delivery
GB8926920D0 (en) * 1989-11-29 1990-01-17 Barry Thomas Inflatable body supports and splints
US5197493A (en) * 1989-12-14 1993-03-30 Kimberly-Clark Corporation Incise system
US5032637A (en) * 1990-03-14 1991-07-16 Adhesives Research Inc. Water-inactivatable pressure sensitive adhesive
JPH0431024A (en) * 1990-05-29 1992-02-03 Toray Ind Inc Manufacture of microporous sheet
US7198046B1 (en) * 1991-11-14 2007-04-03 Wake Forest University Health Sciences Wound treatment employing reduced pressure
US5807290A (en) * 1992-05-29 1998-09-15 South Glamorgan Health Authority Inflatable supports
DE4308445A1 (en) * 1993-03-17 1994-09-22 Beiersdorf Ag Wound dressing based on hydrophilic polyurethane gel foams and process for their production
NZ248977A (en) * 1992-11-09 1995-06-27 Squibb & Sons Inc Pressure-sensitive adhesive comprising a polyurethane having excess hydroxyl functionality; medical articles comprising a layer of such adhesive
CA2116081C (en) * 1993-12-17 2005-07-26 Ann Louise Mccormack Breathable, cloth-like film/nonwoven composite
US5445862A (en) * 1993-12-24 1995-08-29 Tokuyama Corporation Porous film and process for production thereof
FR2721320B1 (en) † 1994-06-20 1996-08-14 Atochem Elf Sa Waterproof-breathable film.
DE4442380A1 (en) 1994-11-29 1996-05-30 Wolff Walsrode Ag Waterproof and breathable fabrics made from resin mixtures of thermoplastic polyurethanes
US5803086A (en) * 1996-05-16 1998-09-08 Minnesota Mining And Manufacturing Company Linerless surgical incise drape
WO1997042904A2 (en) * 1996-05-16 1997-11-20 Minnesota Mining And Manufacturing Company Surgical incise drape
DE69830725T2 (en) * 1997-05-16 2006-05-04 Minnesota Mining And Mfg. Co., St. Paul SURGICAL SINGLE COVER
US20020074691A1 (en) * 1999-09-14 2002-06-20 Robert M Mortellite High speed method of making plastic film and nonwoven laminates
US6656581B2 (en) 1998-05-15 2003-12-02 Clopay Plastic Products Company, Inc. Incrementally stretched non-embossed films having high moisture vapor transmission rates (MVTRs)
US6013151A (en) * 1998-05-15 2000-01-11 Clopay Plastic Products Company, Inc. High speed method of making microporous film products
US6265045B1 (en) 1998-07-29 2001-07-24 Clopay Plastic Products Company, Inc. Method and apparatus for pin-hole prevention in zone laminates
US6092761A (en) * 1998-07-29 2000-07-25 Clopay Plastic Products Company, Inc. In-line web separator
EP1216135B1 (en) * 1999-09-14 2003-05-14 Clopay Plastic Products Company, Inc. High speed method of making plastic film and nonwoven laminates
US7238313B2 (en) * 2001-08-07 2007-07-03 Polymer Group, Inc. Thermoplastic constructs with improved softness
US20030225347A1 (en) * 2002-06-03 2003-12-04 Argenta Louis C. Directed tissue growth employing reduced pressure
US20040039391A1 (en) * 2002-08-23 2004-02-26 Argenta Louis C. Bone treatment employing reduced pressure
US20040122434A1 (en) * 2002-08-23 2004-06-24 Argenta Louis C. Bone treatment employing reduced pressure
US7909805B2 (en) 2004-04-05 2011-03-22 Bluesky Medical Group Incorporated Flexible reduced pressure treatment appliance
US10058642B2 (en) 2004-04-05 2018-08-28 Bluesky Medical Group Incorporated Reduced pressure treatment system
TWI311575B (en) * 2005-12-27 2009-07-01 Ind Tech Res Inst Water-proof and moisture-permeable films and textiles
ATE423169T1 (en) * 2006-02-27 2009-03-15 Ind Tech Res Inst WATER VAPOR PERMEABLE FILMS BASED ON POLYURETHANE AND TEXTILES
DE602007004546D1 (en) † 2006-09-28 2010-03-18 Tyco Healthcare Portable wound therapy system
US7931651B2 (en) 2006-11-17 2011-04-26 Wake Lake University Health Sciences External fixation assembly and method of use
US8377016B2 (en) * 2007-01-10 2013-02-19 Wake Forest University Health Sciences Apparatus and method for wound treatment employing periodic sub-atmospheric pressure
CN101333282B (en) * 2007-06-25 2011-06-29 财团法人工业技术研究院 Water proof and moisture permeable material, thin film and fabric
WO2009049058A1 (en) * 2007-10-10 2009-04-16 Wake Forest University Health Sciences Devices and methods for treating spinal cord tissue
CN103990184A (en) 2008-01-09 2014-08-20 韦克福里斯特大学健康科学院 Device and method for treating central nervous system pathology
JP5457447B2 (en) 2008-07-10 2014-04-02 スリーエム イノベイティブ プロパティズ カンパニー Viscoelastic light guide
ES2633142T3 (en) 2008-07-18 2017-09-19 Wake Forest University Health Sciences Apparatus for modulation of cardiac tissue through topical application of vacuum to minimize death and cell damage
EP3026471A1 (en) 2008-08-08 2016-06-01 3M Innovative Properties Company Lightguide having a viscoelastic layer for managing light
CN102625678B (en) 2009-08-21 2016-01-20 3M创新有限公司 Resistance to water stress distribution material is used to reduce method and the product of tissue injury
US8758237B2 (en) 2009-08-21 2014-06-24 3M Innovative Properties Company Methods and products for illuminating tissue
CN102625677B (en) 2009-08-21 2016-05-18 3M创新有限公司 Alleviate method and the product of tissue injury with water imbibition stress distribution material
CN101724253B (en) * 2009-11-26 2012-03-07 宁波敏禾机械有限公司 Modified thermoplastic polyurethane and preparation method and application thereof
WO2012174204A2 (en) 2011-06-17 2012-12-20 Fiberweb, Inc. Vapor permeable, substantially water impermeable multilayer article
WO2012177996A2 (en) 2011-06-23 2012-12-27 Fiberweb, Inc. Vapor permeable, substantially water impermeable multilayer article
US10369769B2 (en) 2011-06-23 2019-08-06 Fiberweb, Inc. Vapor-permeable, substantially water-impermeable multilayer article
US9765459B2 (en) 2011-06-24 2017-09-19 Fiberweb, Llc Vapor-permeable, substantially water-impermeable multilayer article
US9220627B2 (en) 2011-11-30 2015-12-29 Mark Allen Fisher Abdominal elevator
US9913759B2 (en) * 2012-11-15 2018-03-13 Coloplast A/S Wound dressing
TWI732730B (en) * 2020-12-29 2021-07-01 聚紡股份有限公司 Functional fabric and method for producing the same
CN115073776A (en) * 2021-03-15 2022-09-20 聚纺股份有限公司 Functional fabric and method for producing same
CN114681681B (en) * 2021-07-07 2023-06-30 浙江天原医用材料有限公司 Material for medical catheter as well as preparation method and application thereof

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3426754A (en) * 1964-06-12 1969-02-11 Celanese Corp Breathable medical dressing
DE1769089C3 (en) * 1968-04-02 1975-03-06 Bayer Ag, 5090 Leverkusen Process for the production of, optionally microporous, shaped bodies
US3536638A (en) * 1968-11-08 1970-10-27 Uniroyal Inc Breathable films of organic plastic material containing incompatible thermoplastic resin particles incorporated therein
US3932682A (en) * 1970-06-04 1976-01-13 Celanese Corporation Air permeable waterproof products having fabric-like aesthetic properties and methods for making the same
US3993618A (en) * 1971-09-07 1976-11-23 Statni Vyzkumny Ustav Kozedelny Coatings for fibrous sheet material of polyurethane and oil-like hydrocarbon polymer
US3975316A (en) * 1972-05-04 1976-08-17 Thiokol Corporation Curing liquid polyurethane prepolymers
US3844865A (en) * 1972-06-06 1974-10-29 Minnesota Mining & Mfg Method of making stretch-oriented porous films
US3870593A (en) * 1972-06-06 1975-03-11 Minnesota Mining & Mfg Stretch-oriented porous films and preparation and use thereof
GB1476791A (en) * 1973-06-11 1977-06-16 Matsushita Electric Ind Co Ltd Process for producing porous polymer film
US4133310A (en) * 1974-01-11 1979-01-09 Smith & Nephew Research Limited Polymer fabric

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0072258A2 (en) * 1981-08-12 1983-02-16 Smith and Nephew Associated Companies p.l.c. Adhesive dressing and components
EP0072258A3 (en) * 1981-08-12 1983-06-15 Smith And Nephew Associated Companies P.L.C. Adhesive dressing and components
US4559938A (en) * 1981-08-12 1985-12-24 Smith And Nephew Associated Companies P.L.C. Adhesive dressing and components
US4596738A (en) * 1983-10-22 1986-06-24 Smith And Nephew Associated Companies P.L.C. Polymer blend films
AU574391B2 (en) * 1983-10-22 1988-07-07 Smith & Nephew Associated Companies Plc Ethylene-vinyl acetate copolymer films
US4605165A (en) * 1984-06-13 1986-08-12 International Flavors & Fragrances Inc. Constant rate volatile composition dispensing article and process for using same
US4614299A (en) * 1984-06-13 1986-09-30 International Flavors & Fragrances Inc. Article which dispenses at a constant rate a volatile composition, and process for using same
US6592995B2 (en) * 2001-07-24 2003-07-15 Kimberly-Clark Worldwide, Inc. Humidity activated materials having shape-memory
US6627673B2 (en) * 2001-07-24 2003-09-30 Kimberly-Clark Worldwide, Inc. Methods of making humidity activated materials having shape-memory
US6933421B2 (en) * 2001-07-24 2005-08-23 Kimberly-Clark Worldwide Inc. Methods of making disposable products having humidity activated materials with shape-memory

Also Published As

Publication number Publication date
ZA815523B (en) 1982-09-29
CA1177208A (en) 1984-11-06
EP0046071A2 (en) 1982-02-17
DE3162807D1 (en) 1984-04-26
ATE6741T1 (en) 1984-04-15
AU7400081A (en) 1982-03-04
EP0046071B1 (en) 1984-03-21
DK168633B1 (en) 1994-05-09
DK358781A (en) 1982-02-14
IE51473B1 (en) 1986-12-24
EP0046071A3 (en) 1982-05-05
NZ197988A (en) 1984-03-30
IE811793L (en) 1982-02-13
JPH0235779B2 (en) 1990-08-13
AU545048B2 (en) 1985-06-27
GB2081721B (en) 1984-05-23
JPS5763229A (en) 1982-04-16
US4452845A (en) 1984-06-05

Similar Documents

Publication Publication Date Title
GB2081721A (en) Porous drawn polyurethane blended polymer films
US4559938A (en) Adhesive dressing and components
KR101519689B1 (en) Film formed from a blend of biodegradable aliphatic-aromatic copolyesters
KR960005590B1 (en) Porous film, process for producing the same, and absorbent sanitary articles
US5614588A (en) Polymer mixture and films prepared therefrom
RU2192512C2 (en) Breathing film laminate with filler
US6072005A (en) Breathable films and process for producing them
JP3414739B2 (en) Elastic materials and products made therefrom
AU750714B2 (en) Microlayer breathable films of degradable polymers and thermoplastic elastomers
AU706767B2 (en) Multilayer breathable film and a method for making a multilayer breathable film
JP2003508254A (en) Breathable multilayer film having a cracking skin layer
CN1305508A (en) Low viscosity thermoplastic compositions for structures with enhanced moisture vapour permebility and the utilisation thereof in absorbent articles
KR100606300B1 (en) Water Soluble Polyethylene Oxide Films
KR20020055588A (en) Coextruded, Elastomeric Breathable Films and Process for Making Same
CA2422615A1 (en) Multilayer polyolefin film as a pvc replacement film
JPH04298564A (en) Polyblock containing polymer blend
JPS62129321A (en) Production of porous sheet
KR20000071181A (en) Breathable Multilayer Foil
DE60011775T2 (en) STICKY OBJECT WITH DIFFERENT PHASES
KR900008705B1 (en) Method for the preparation of grain face artificial leather

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 20000807