Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D167/00—Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain; Coating compositions based on derivatives of such polymers
  • C09D167/08—Polyesters modified with higher fatty oils or their acids, or with natural resins or resin acids
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D167/00—Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain; Coating compositions based on derivatives of such polymers
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
  • C09D5/29—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes for multicolour effects
• • 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
  • Y10T428/263—Coating layer not in excess of 5 mils thick or equivalent
  • Y10T428/264—Up to 3 mils
• • 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
  • Y10T428/263—Coating layer not in excess of 5 mils thick or equivalent
  • Y10T428/264—Up to 3 mils
  • Y10T428/265—1 mil or less

Definitions

• This invention relates to a method of coating steels which acquires a protective and decorative oxide patina on weathering, to compositions for coating such steels, and to the coated product.
• the surface of certain high-strength low-alloy steels weathers through oxidation to a dark earthy color.
• the oxide patina which forms is extremely dense and adherent, and inhibits further corrosive attack. It also has an attractive appearance.
• the weathering process may take several years, and in the meantime a structure in which such steel is exposed to view does not have its full attractiveness. As far as we are aware, the weathering process cannot be hastened, but must take place only through natural exposure.
• An object of our invention is to provide a method of coating scale-free steel of the foregoing type to simulate the appearance it acquires after weathering.
• a further object is to provide a method of achieving this appearance Without hindering natural weathering processes, and with a coating which degrades gradually and uniformly in approximately the same time as required for weathering.
• a further object is to provide improved coating compositions which have a low pigment-to-binder ratio and which degrade by gradual uniform erosion resembling chalking, whereby they give a steel surface a weathered appearance without inhibiting the natural weathering.
• a further object is to provide a coated steel product which simulates the appearance of weathered steel, but which subsequently weathers normally.
• our invention we first pickle or blastclean the surface of the steel until it is scale-free.
• a composition which consists of a vehicle binder, a pigment, and a thinner or solvent.
• the binder is a film-forming, adherent, resinous, organic substance susceptible to degradation by ultraviolet light and weathering to a chalky, porous material when applied to a metal substrate as a film of 0.2 to 2.0 mil thickness.
• Our preferred binder is a water-soluble polymerized soya oil, but we also have used successfully shellac solutions, styrenated alkyd solids and oleoresinous varnishes.
• Our composition has a much lower pigment-to-binder ratio than conventional coating compositions, where the objective is to produce lasting coatings.
• a minimum ratio of pigment to binder of about 0.1 by weight and a maximum ratio of about 0.4, or preferably a ratio between about 0.20 and 0.25.
• a ratio below our minimum does not furnish sufiicient pigment to color the steel, while a ratio above our maximum inhibits natural weathering.
• These ratios are in contrast to a minimum ratio of about 0.8 used in conventional paints, or more often 1.0 to 2.0.
• sufiicient thinner to produce a composition which is readily applied as a thin coating in the range of 0.2 to 2.0 mils thickness. The proportion of thinner is about 35 to percent by weight of the total composition.
• Specific examples of compositions within our invention are as follows:
• the binder was a water-reduced polymer derived from soya oil. We synthesize the binder by forming an ammoniumr salt of a polycarboxylated glyceride (maleated soya bean oil). Thus the binder is miscible with water.
• the composition was as follows:
• the binder was a shellac solution.
• the composition was as follows:
• Shellac solids 24 Denatured alcohol 24 Burnt umber 3 Brown iron oxide 3
• the pigment-to-binder ratio was 0.25.
• the binder was a styrenated alkyd synthetic resin formed by modifying a conventional alkyd resin through copolymerization with styrene monomer.
• We form the alkyd resin by polymerizing a polyhydric alcohol, such as glycerol, with a difunctional anhydride, such as I phthalic anhydride, and a long chain unsaturated vegetable oil, such as linseed or soya bean oil.
• styrene monomer to this polymer.
• Styrene alkyd resins dry more rapidly in air and produce harder films than conventional drying alkyd resins.
• the drier can be one of the common metallic driers used in paints and varnishes, such as lead, cobalt, manganese, zinc, calcium, zirconium and rare earth driers.
• Driers are solutions in mineral spirits of heavy metal soaps of organic acids which form stable mixtures with most alkyd and oleoresinous binders. The composition of this example was as follows:
• the pigment-to-binder ratio was 0.20. We added pigment to approximately half the binder and ground the mixture in a pebble mill to proper fineness. Thereafter we added the remainder of the binder with thorough mixing.
• the binder was a rosin-ester type varnish prepared through high-temperature copolymerization of unsaturated, long-chain vegetable oils, such as oiticica oil, with rosin ester resins.
• Rosin ester resins are the reaction products of the polymerization of rosin and polyhydric alcohols, modified by incorporating para-substituted phenols. Typical para-substituted phenols are bis-phenol, p-tertiary butyl phenol, p-tertiary amyl phenol, and pphenyl phenol.
• Rosin ester resins also may be modified by formation of adducts with the resin prior to polymerization With the polyhydric alcohol. These adducts are prepared by reacting rosin with such difunctional materials as maleic anhydride or fumaric acid.
• the composition of this example Was as follows:
• the pigment-to-binder ratio was 0.25.
• a method of treating a high-strength low-alloy steel body of the type which acquires a protective and decorative oxide patina on its surface after it weathers for a protracted period comprising:
• a coating of a composition which consists of a pigment, a water soluble polymerized soya oil and water and ammonium hydroxide as thinner binder,
• the pigment-to-binder ratio being about 0.1 to 0.4 by
• said pigment matching the color which the body acquires later after weathering, and being selected from the group consisting of raw and burnt umbers, red and brown iron oxides, raw and burnt siennas, carbon black, and combinations thereof;
• binder being a film-forming adherent, resinous
• said solvent constituting about 35 to percent by weight of the composition
• said coating having a thickness of 0.2 to 2.0 mils
• the body initially has an appearance similar to that which it acquires later after weathering.
• composition has a pigment-to-binder ratio between about 0.20 and 0.25 by weight.
• a structure having incorporated therein steel members prepared by the method defined in claim 1.

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• Chemical & Material Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Wood Science & Technology (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Paints Or Removers (AREA)
• Application Of Or Painting With Fluid Materials (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=24223318

Family Applications (1)

Country Status (4)

Cited By (1)

Citations (5)

• 1966
  • 1966-06-13 US US556908A patent/US3502512A/en not_active Expired - Lifetime
• 1967
  • 1967-06-09 ES ES341591A patent/ES341591A1/es not_active Expired
  • 1967-06-09 BE BE699760D patent/BE699760A/xx unknown
  • 1967-06-12 NL NL6708146A patent/NL6708146A/xx unknown

Patent Citations (5)

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