Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D5/00—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures
  • B05D5/02—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures to obtain a matt or rough surface
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
  • B05D7/02—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to macromolecular substances, e.g. rubber
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
  • C08J7/04—Coating
  • C08J7/0427—Coating with only one layer of a composition containing a polymer binder
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
  • C08J7/04—Coating
  • C08J7/043—Improving the adhesiveness of the coatings per se, e.g. forming primers
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
  • H01M50/233—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by physical properties of casings or racks, e.g. dimensions
  • H01M50/24—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by physical properties of casings or racks, e.g. dimensions adapted for protecting batteries from their environment, e.g. from corrosion
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
  • C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2423/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
• • 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
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/10—Energy storage using batteries

Definitions

• This invention relates to surface treatment of polyolefin parts, in particular, to permanently bonding granular materials to surfaces of polyethylene parts such as containers and outdoor signs.
• Polyolefin surfaces particularly polyethylene surfaces, resist acceptance of coatings. These polymers are commonly used to form large, hollow-form parts such as outdoor signs, tanks and containers by rotational molding. The surfaces of these parts are smooth and difficult to coat.
• U.S. Pat. No. 5,840,142 discloses and claims a method for the permanent application of indica to the surface of a molded polyethylene part using a transfer which is screen printed with a wax, polyethylene and pigment mixture. After application to the surface of a polyethylene part, the transfer is coated with a mixture of polyethylene and wax and the part is heated to fuse the coating and transfer into the surface of the part.
• the method of this patent cannot be used to create a part with a roughened or textured surface, since the method achieves complete integration of the applied coatings into the surface of the part, forming a smooth clear surface.
• This invention is a method to impart a permanent, roughened or textured surface to parts molded from polyolefins, particularly from polyethylene.
• the method comprises coating the selected surface of the part with a coating mixture of a tackifier resin and polyolefin particles in a liquid carrier and incorporating a granular or particulate matter in the coating, either by application to the coating or by admixing the granular or particulate matter into the coating mixture.
• the invention also includes the composition of the coating mixture.
• the coated surface of the polyethylene part is heated to the melt temperature of the polyolefin for a short time, sufficient to gel the polyolefin particles of the coating into the surface of the part, but insufficient to cause any thermal distortion of the part.
• the heating permanently incorporates the coating into the surface of the part, with the granular solids bonded to the surface to impart a roughened or textured surface.
• the invention is applicable to the treatment of surfaces of polyolefins such as polymers and copolymers of ethylene, propylene, butene, isobutene, with minor amounts of other comonomers such as vinyl acetate, vinyl chloride, etc.
• polyolefins such as polymers and copolymers of ethylene, propylene, butene, isobutene, with minor amounts of other comonomers such as vinyl acetate, vinyl chloride, etc.
• Polyethylene is the most common and advantageously treated polyolefin and is preferred, however, the surfaces of other polyolefins can be likewise treated.
• the treatment of the invention is applicable to provide a roughened or textured surface to polyolefins in any form or shape, including films and sheets and molded objects such as containers, e.g., boxes, tanks, and outdoor signs, which are commonly rotationally molded from polyethylene.
• the method employs a coating adhesive mixture which is applied to the polyolefin surface as a thin coating approximately several mils or less, preferably one mil, in thickness.
• the coating can be applied by any conventional method such as spraying, brushing, rolling, etc. Spraying is preferred for ease of application.
• the active ingredients in the coating mixture are powders of a polyolefin, preferable polyethylene and a tackifier.
• the polyethylene powder and tackifier are present in relative proportions of 15-30 weight parts tackifier and 85-70 weight parts polyethylene powder per 100 weight parts.
• These ingredients are dispersed in a suitable liquid carrier to permit application to the polyolefin surface.
• the liquid carrier can be water or a hydrocarbon solvent such as hexane or toluene.
• the tackifier should be compatible with the polyolefin and preferably should be white to neutral in color to avoid staining the polyolefin surface. It should also have a softening temperature less than the melting temperature of the polyolefin, which for polyethylene should be less than 250 degrees F.
• Useful tackifiers include polyacrylic acid polyacrylates, polyurethanes, poly(vinyl)acetate and copolymers and mixtures thereof.
• Particularly preferred tackifiers are hydrocarbon resins such as aliphatic or cycloaliphatic petroleum resins from five carbon monomers containing minor amounts of aromatics, synthetic terpene resins, chlorinated polyolefins and hydrogenated rosin and rosin esters.
• the tackifier should be of light color to avoid staining the polyolefin surface, should have high heat and ultraviolet light stability and be soluble in hydrocarbon solvents or be readily emulsifiable in water.
• the softening point of the tackifier should be from 75 to 135 degrees F., preferably from 85 to 120 degrees F.
• the polyolefin ingredient is used in a finely subdivided or powdered state with a particle size from less than 1 micron to about 140 microns, preferably from 5 to about 40 microns, maximum particle diameter.
• the density of the preferred polyethylene powder ranges from about 0.88 to 0.97 grams per cubic centimeter.
• Low, high and linear high density and high to ultrahigh molecular weight polyethylene can be used.
• Other suitable polyolefins include polypropylene, ethylene/vinyl acetate copolymers, and metallocene catalyst polyethylene.
• the coating mixture has sufficient liquid carrier to provide a solids content from 30 to about 50, preferably from 25 to 35, weight percent, and can be thinned with additional liquid carrier to provide an appropriate viscosity for application by spraying, brushing, rolling, or dipping of the polyethylene surface with the coating mixture.
• the active ingredients are dispersed in water with surface active agents which can include hydrocarbon silicone and fluorocarbon surfactants, non-ionic surfactants and ionic surfactants.
• surface active agents can include hydrocarbon silicone and fluorocarbon surfactants, non-ionic surfactants and ionic surfactants.
• Sufficient amounts of the surfactant are used to achieve a stable suspension of the ingredients in the aqueous mixture.
• the effective concentration of the surfactant will be from 0.1 to about 2 weight percent of the solids content in the aqueous mixture, depending on the particular surfactant which is used.
• the granular solids can be of various sources, selected for the particular application.
• suitable materials include silica, e.g., sand, silicon carbide, aluminum oxide, aluminum silicates, garnet, etc. If skid resistance is desired, sand or garnet powders can be used. If an abrasive surface is desired, silicon carbide or alumina can be used. In some applications, a highly reflective surface may be desired and reflective glass beads or microspheres, or metal flakes can be used.
• the particle size of the granular solids can be varied considerably from 15 to about 300 mesh. The preferred size range is from 100 to about 300 mesh.
• the granular solids can be admixed into the coating mixture when the mixture is applied by brushing, rolling or dipping.
• the coating mixture can be loaded with granular solids in amounts of 5 to 50 weight percent, preferably 15 to 30 weight percent.
• the coating mixture is applied by spraying, the granular solids are spread across the wetted surface of the polyethylene part by dusting or other suitable techniques that will ensure uniform distribution of the solids.
• the coated surface is then heated to raise the temperature of the coating and outer skin of the surface to the melt temperature of the polyolefin powders, fusing the powders and tackifier into the outer skin of the polyolefin surface.
• the granular solids are thereby encased in the outer skin of the polyolefin part, yet protrude from the surface of the part to impart a roughened texture to the surface.
• the coated polyolefin surface is heated to a temperature from 250 to about 350 degrees F., taking care to avoid excessive temperatures or temperature differentials which could cause the polyolefin part to distort or warp.
• the heating can be accomplished using a suitable radiant source such as an open flame or a high temperature electrical heater, e.g., an infrared heater.
• the heating step is practiced to apply heat locally to the coated polyethylene surface sufficiently to fuse the coating into the surface of the polyolefin part, a condition which is reached when the coated surface appears to be clear of any cloudiness.
• the polyolefin part is cooled to ambient temperature.
• a battery container having a cover approximately two by three feet in area and obtained by rotationally molding from polyolefin is treated by the invention to provide skid resistance suitable for use as a step.
• a coating mixture of active ingredients comprising 30 weight percent of an aromatic modified C5 aliphatic hydrocarbon resin and 70 weight percent polyethylene powders was used to coat the outer surface of the container cover.
• the polyethylene powder was high density polyethylene with a size range from 1 to 80 microns.
• the active ingredients were dispersed in toluene at a concentration of 25 weight percent and were sprayed onto the polyethylene surface sufficiently to form a continuous film over the surface.
• a pumice aggregate containing 70 weight percent silica with a size range from 15 to 100 mesh was dusted over the wet surface of the coating and a second coating of the coating mixture was sprayed over the surface. The coating was permitted to dry and then the surface was heated to approximately 250 degrees F., sufficiently to fuse the coating into the outer skin of the polyethylene surface. After cooling the granular solids were observed to have imparted a permanent, roughened texture to the polyethylene surface.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Health & Medical Sciences (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Wood Science & Technology (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Coating Of Shaped Articles Made Of Macromolecular Substances (AREA)
• Paints Or Removers (AREA)
• Processes Of Treating Macromolecular Substances (AREA)

Priority Applications (11)

Applications Claiming Priority (1)

Related Child Applications (1)

Publications (1)

Family

ID=25426593

Family Applications (2)

Family Applications After (1)

Country Status (10)

Cited By (2)

Families Citing this family (7)

Family Cites Families (11)

• 2001
  • 2001-07-20 US US09/909,066 patent/US20030017272A1/en not_active Abandoned
• 2002
  • 2002-07-17 MX MXPA04000523A patent/MXPA04000523A/es unknown
  • 2002-07-17 JP JP2003513705A patent/JP2005504621A/ja active Pending
  • 2002-07-17 CA CA002453265A patent/CA2453265A1/fr not_active Abandoned
  • 2002-07-17 BR BR0211268-0A patent/BR0211268A/pt not_active IP Right Cessation
  • 2002-07-17 IL IL15974902A patent/IL159749A0/xx unknown
  • 2002-07-17 NZ NZ531250A patent/NZ531250A/en unknown
  • 2002-07-17 EP EP02747056A patent/EP1409154A4/fr not_active Withdrawn
  • 2002-07-17 WO PCT/US2002/022958 patent/WO2003008108A1/fr active IP Right Grant
• 2003
  • 2003-09-22 US US10/667,746 patent/US7465473B2/en not_active Expired - Fee Related
• 2004
  • 2004-01-19 NO NO20040233A patent/NO20040233L/no not_active Application Discontinuation

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