Classifications

• • A—HUMAN NECESSITIES
  • A41—WEARING APPAREL
  • A41D—OUTERWEAR; PROTECTIVE GARMENTS; ACCESSORIES
  • A41D19/00—Gloves
  • A41D19/0055—Plastic or rubber gloves
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C33/00—Moulds or cores; Details thereof or accessories therefor
  • B29C33/42—Moulds or cores; Details thereof or accessories therefor characterised by the shape of the moulding surface, e.g. ribs or grooves
  • B29C33/424—Moulding surfaces provided with means for marking or patterning
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B42/00—Surgical gloves; Finger-stalls specially adapted for surgery; Devices for handling or treatment thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
  • B29C41/003—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor characterised by the choice of material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
  • B29C41/02—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles
  • B29C41/14—Dipping a core
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2075/00—Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
  • B29K2995/0037—Other properties
  • B29K2995/0077—Yield strength; Tensile strength
• • 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
  • Y10T428/31504—Composite [nonstructural laminate]
  • Y10T428/31551—Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• • 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
  • Y10T428/31504—Composite [nonstructural laminate]
  • Y10T428/31551—Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
  • Y10T428/31554—Next to second layer of polyamidoester

Definitions

• This invention relates to polyurethane articles, particularly to thin- walled articles made by dipping, and especially (but not exclusively) to gloves of the sort used by surgeons.
• polyurethane One alternative material is polyurethane.
• Polyurethanes are available which have a higher modulus than natural rubber and these materials can be used to make gloves which are thinner than natural rubber gloves and have a higher tensile strength.
• these stiffer polyurethanes are too hard to give a good surface grip. They tend to have a shiny surface which, particularly in moist or wet conditions, is slippery. It is, of course, very important that articles such as surgeons' gloves should have good grip surfaces, especially in moist and wet conditions. -9.
• a method of forming a thin-walled article comprises coating a roughened former with a first elastomer, which first elastomer substantially does not retain any bubbles that may be formed; coating a high modulus polyurethane to the coated former to form the main body of the article; drying and/or curing the composite article; and stripping the composite article from the former, whereby the surface of the first elastomer has a rough surface to provide surface grip.
• the polyurethane glove (or other article) has a roughened grip surface derived from the effect of the roughened former, without the problem of bubble formation in the polyurethane.
• the first elastomer is coated on the former by dipping the former into the first elastomer.
• the high modulus polyurethane is preferably coated on the former by dipping the former into said polyurethane
• a thin-walled article comprising a grip coating of a first elastomer on a high modulus polyurethane substrate, wherein the coating has a rough surface to provide surface grip.
• the polyurethane will normally be a thermoplastic polyurethane (although curable polyurethanes can be used) and will normally have a modulus (i.e a modulus at 100%) extension of at least about 2 MPa, but usually no greater than about 5 MPa.
• modulus i.e a modulus at 100%
• polyurethanes which may be used, including for example polyether polyurethanes (e.g. Avalon 80 AT), polyester polyurethanes (e.g. Avalon 70 AE, Estane 5710, Ellastolan 80A), polycaprolactone polyurethanes (Avalon 75 AC) (Avalon products are available from ICI, Estane products from BFG, and Ellastolan products from BASF).
• the high modulus polyurethanes used m the invention are normally in organic solvent solutions, but some water-based polyurethanes can be used.
• the articles of the invention may be made for example by dipping a roughened former into a solution or dispersion of the grip coating elastomer and then into a solution or dispersion of the polyurethane mate ⁇ al.
• the gloves (or other articles) are turned inside out upon removal from the former. Smce manufacture of laminated thin-walled articles in this general way is well known in the art, further detailed desc ⁇ ption will not be given.
• an aqueous dispersion is used which will normally not give ⁇ se to any bubble formation.
• organic solvent solutions or dispersions can be used but the solution or dispersion will preferably have a relatively low viscosity so that any bubbles which are formed will escape therefrom during and after dipping, and when drying.
• the viscosity to be no more than about 800 cps (8 Nm "2 s) and preferably below 600 cps (6 Nm-2s), measured on a Brookfield viscometer at a speed of 12 rpm using an LV2 spindle at 25°C ⁇ 2°C).
• the final grip coating will preferably be completely free of bubbles.
• the elastomer grip coating serves by its roughened surface to provide grip.
• the elastomer will be chosen to provide other properties not available in the high modulus polyurethane.
• the elastomer used to provide the surface coating be softer than the substrate polyurethane.
• Suitable coating polymers include soft polyurethanes, block copolymers such as styrene-isoprene-styrene or styrene-ethylene-butylene-styrene, natural rubber, polyvinylchloride (PVC), synthetic rubbers such as silicone, acrylic, nitrile and polychloroprene.
• PVC polyvinylchloride
• silicone silicone
• acrylic nitrile
• polychloroprene for the best adhesion between the coating and the underlying hard polyurethane, we prefer to use a coating of polyurethane, styrene-ethylene-butylene-styrene or self-crosslinking acrylonitrile latex.
• Highly preferred coating materials are soft, aliphatic, aqueous polyurethane dispersions, such as Quilastic 148-56 from Merquinsa (Spain).
• thermoset polymer for the grip coating.
• An example of a thermoset polymer for this purpose is a self-crosslinking polyurethane latex, e.g. Milloxane 280 (available from Polyurethane specialists).
• the grip coating should preferably be a non-newtonian fluid and exhibit a fair degree of pseudoplasticity to reduce the risk of defects occurring during application.
• the grip coat will preferably have a lower specific heat capacity than the former, so that heat is dissipated more effectively in the micro- environment of the post coating interface. It is also preferred that the grip coat should be at such a solids content as to create a smoothing effect on the former surface so that there are no nucleation points for bubble formation when the high modulus polyurethane is applied thereover.
• the grip coating must be chemically compatible with the high modulus polyurethane coating and not adversely affected by solvent diffusion.
• the polyurethane gloves and other articles of the present invention combine the advantages of hard polyurethanes, namely high strength and low thickness, with the surface grip advantages of a roughened surface elastomer.
• Standard production surgeons' glove formers are known in three different surface finishes, these are glazed (essentially smooth), biscuit or bisque finish (non-glazed, quite rough as they appear from the cast) and macro-roughened (particles in the glaze effect a roughening of, most commonly, about 40 micrometres).
• biscuit and micro-roughened formers can be used in accordance with the present invention, we have found that it is preferable to use a former which has been very finely roughened
• a former which has been very finely roughened
• alumina 400 which has 17 micrometres mean diameter particles. This treatment gives the former a very finely roughened angular finish with a matt appearance. Whilst this is our currently preferred method of making the special formers, it may be possible to make them in other ways and the invention is not limited to the particular blasting method described above.
• the finely roughened formers which we prefer to use have a surface roughness which can be measured using a "Tally-Surf' probe instrument.
• the resulting International Parameter of Roughness otherwise called the Ra value or mean peak to valley height, is generally in the range of about 0.5 to about 1.5 micrometres, pieferably about 1 0 microometie
• the distance between profile peaks at the measured mean line (Sm) is generally in the range 30 to 70 micrometres, preferably about 50 micrometres
• the degree of roughening of the formers of the invention can be va ⁇ ed to suit the characteristics of the surface coating being used, to provide the desired grip performance. Routine trial and experiment will enable optimum conditions to be established in any particular case In general, the use of the fmely roughened formers of the invention gives the gloves (or other articles) a matt fmish which is aesthetically pleasing. It also greatly reduces the tack of the surface coating.
• the formers also provide an important processing advantage in the manufacture of the articles of the invention.
• Gloves were made by dipping two formers first into an elastomer dispersion (to fo ⁇ n the outer grip coating) and then into an aromatic thermoplastic solution grade polyurethane to form the main body of the glove.
• the materials used, and the different formers, are identified below.
• gloves were also made from the polyurethane only (no surface coating).
• the gloves so formed were examined for visual appearance and for surface tack They were then tested for grip under wet and dry conditions The results were as follows.
• Finely roughened former according to invention V (a) Polyurethane only: non-tacky, harsh feel, matt finish, some bubbling evident
• the mean volume test is a subjective test where panel members grip a 1 litre measuring cylinder with a gloved hand. Water is poured into the cylinder until slippage is observed.
• the elastomer dispersion was prepared by taking the high solids elastomer latex Milloxane 280 (ex PU Specialities, New Jersey, USA) and diluting to 10% with deionised water. The systems rheology was controlled by the addition of 0.2% Xanthan gum thickener, (ii) Polyurethane solution
• the finely roughened former was obtained by blasting a standard glazed former with alumina particles of 17 ⁇ m mean diameter at a pressure of approximately 80 psi (0.55 x 10 6 Pa) Method
• the former was dipped into a bath of the elastomer dispersion (grip coat), and then withdrawn and the coating dried.
• the coated former was then dipped into the polyurethane solution and then withdrawn. A bead was formed in the conventional way and the polyurethane coating dried.
• the former was then dipped in hot water for 10 minutes, after which the glove so formed was stripped from the former and dried.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Surgery (AREA)
• Animal Behavior & Ethology (AREA)
• Heart & Thoracic Surgery (AREA)
• Medical Informatics (AREA)
• Molecular Biology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Biomedical Technology (AREA)
• Textile Engineering (AREA)
• Gloves (AREA)
• Moulds For Moulding Plastics Or The Like (AREA)
• Coating Of Shaped Articles Made Of Macromolecular Substances (AREA)
• Laminated Bodies (AREA)
• Materials For Medical Uses (AREA)
• Organic Insulating Materials (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Processes Of Treating Macromolecular Substances (AREA)
• Moulding By Coating Moulds (AREA)

Priority Applications (8)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

Country Status (11)

Families Citing this family (23)

Citations (9)

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• 1996
  • 1996-06-13 GB GBGB9612324.5A patent/GB9612324D0/en active Pending
• 1997
  • 1997-06-12 JP JP10501368A patent/JP2000511843A/ja not_active Ceased
  • 1997-06-12 DE DE69707450T patent/DE69707450T2/de not_active Expired - Fee Related
  • 1997-06-12 AT AT97926111T patent/ATE206997T1/de not_active IP Right Cessation
  • 1997-06-12 EP EP97926111A patent/EP0906178B1/en not_active Expired - Lifetime
  • 1997-06-12 US US09/202,362 patent/US6143416A/en not_active Expired - Fee Related
  • 1997-06-12 CA CA002257150A patent/CA2257150C/en not_active Expired - Fee Related
  • 1997-06-12 DK DK97926111T patent/DK0906178T3/da active
  • 1997-06-12 AU AU30996/97A patent/AU710210B2/en not_active Ceased
  • 1997-06-12 ZA ZA9705206A patent/ZA975206B/xx unknown
  • 1997-06-12 WO PCT/GB1997/001595 patent/WO1997047451A1/en not_active Ceased

Patent Citations (9)

Non-Patent Citations (1)

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