CA1062558A - Process for decorating coatings produced by heat-stable polymer compositions - Google Patents

Abstract

A PROCESS FOR DECORATING COATINGS PRODUCED
BY HEAT-STABLE POLYMER COMPOSITIONS

ABSTRACT OF THE DISCLOSURE

The appearance of a heat-stable polymer coating is enhanced by a process which produces a decorative pattern within a coating produced by a heat-stable polymer coating composition. The process consists of applying a heat-stable polymer composition as a subsequent coat over or directly under an antioxidant composition in a decorative pattern. The antioxidant composition diffuses into the heat-stable polymer coating composition and renders the pattern visible, upon baking, within the baked coat produced by the coating composition.

Description

1~6;~558 BACKGROUND OF THE INVENTION
Fleld of Invention This invention relates to a process which renders a decorative pattern visible wlthin a coating produced by a heat-stable polymer coatlng composition.
Prior Art Articles coat~d with heat-stable polymer composi-tions of various types have come into widespread use in recent years, Heat-stable polymer coated artlcles are useful for purposes requiring or aided by a heat-stable surface. Espe-cially useful are heat-stable polymer coating compositions whlch provide lubricious surfaces. The uses of coated arti-cles-having lubricious surfaces range from bearings to ship bottoms and from iron soleplates to ice cube trays.
To achieve maximum consumer demand for an article consumer expectations must be met. One consumer expectation ls to have a product which is pleasing to his or her aesthetic sense and which is capable of maintaining this pleasing effect throùghout the product's useful life.
The process of this invention produces a decorative pattern visible witbin coatings produced by a heat-stable polymer coatlng composition, thereby achieving this consumer expectation. By decorative pattern is meant any image, picture, design, configuration, or illustration which can be formed by any conventional method of applying ink.
Decoratlve areas of the coating wear as well as non-decorative areas for the following reasons. The decorative pattern extends through the entire thickness of the coating;
therefore as the coating is worn thinner the decorative pattern ls still present. Concentratlon of heat-stable

- 2 -l~Z558 polymer is uniform throughout the coating, i.e., the decorative and non-decorative areas; therefore, the coating has unlform heat stabillty throughout. Thickness of the coat-ing iæ uniform, i.e.~ neither the decoratlve nor non-decorative areas are higher than the other, thereby not facilitating chipping of a higher ar~ea.
SUMMARY OF THE INVENTION
According to the ~resent invention there is provided a process which renders a decorative pattern vlsible within a lo baked coating produced by a heat-stable polymer coating compos:~tton. The process consiæts essentially of applying the heat-stable polymer coating composition elther as a sub-sequent coat over or directly under an antioxidant composi-tion which is arranged in a decorative pattern, wherein the ~ntioxidant or lts decomposition products diffuse into the coat and either by reacting with components of the coating, by catalyzing reactions within the coating or by ltself renders, upon baking, the decorative pattern visible within the coating produced by the heat-stable coating composition DETAILED DESCRIPTION OF THE INVE~ION

A heat-stable polymer composition consistæ of at least one heat-stable polymer and a liquid carrier A heat-stable polymer is a polymer which is not affected by temperatures above ~00C which would decompose, oxidize or otherwise adversely affect most organic compounds.
Some exampleæ of heat-stable polymers are silicones, poly-sulfldes, polymerized parahydroxy benzoic acid, polysulfones, polyimides, polyamides, polysulfonates, polysulfonamide~, 1~625S8 H-reælns (sold by Hercules Corporation), and fluorocarbons.
~ne or more h~at-stable polymers can be present ln the composition of thls invention.
The preferred heat-stable polymers are fluoro-carbons because of their high temperature stability and release properties. The fluorocarbon polymers used are those of hydrocarbon monomers completely substituted with fluorine atoms or a combination of fluorlne and chlorine atoms. Included in this group are perfluoroolefin polymers such as polytetrafluoroethylene (PTFE) and copolymers of tetrafluoroethylene and hexafluoropropylene in all monomer unit weight ratios, fluorochlorocarbon polymers such as poly-monochlorotrifluoroethylene, and copolymers of tetrafluoro-ethylene and perfluoroalkyl vinyl ethers. Mixtures of these can also be used.
The heat-stable polymer is ordinarily present in the composition at a concentration of 25~ through 95~ pre-ferably 70% through 90%, by weight of the total sollds present in the composition.
Although a dry flour or powder of a heat-~table polymer can be used and a liquid carrier provlded separately, a polymer in the form of an aqueous surfactant-stabilized dispersion is preferred for its stability and because it is most easily obtalned in that form Dispersions of heat-stable polymers in organic liquids such as alcohols, ketones, aliphatics or aromatic hydrocarbons, or mixtures of these, can also be used. In either case, the llquld generally serves as the carrler for the composition.
If desired a colorant may be present in the heat-stable polymer composition. A colorant is any compound which ~062558 changes color when oxidized. Car~on and carbonaceous residues are examples of colorants.
For the purpose of this invention a reaction such as oxidation of carbon black to carbon dioxide, in which a solid is oxidized to a fugitive gas, the solid thereby vanish~
lng from the composition, is considered a color change.
Carbon can be present in concentrations up to 40%
based on the weight of total solids of the composition, preferably in concentrations of .5-10%.
Carbonaceous resldues are Produced b.y decomposition or partial oxidation of organic compounds, which includes organometallic compounds. Organic compounds are normally present in coating compositions to serve as dispersants, coalescing agents, viscosity builders, etc. or they can be added to serve as colorants.
Although absolute amounts of carbonaceous residues in the heat-stable polymer coating are usually extremely small, nevertheless, they give a definite coloration to a baked coat-lng, Examples of organic compounds which produce carbon-aceous residues are polymers of ethylenically unsaturated monomers, which depolymerize, and whose depolymerization products vaporize, in the temperature range of from 150C
below the fusion temperature to about the heat-stable polymer's decomposition temperature.
"Depolymerization" means degradation of a ~olymer to the point at which the degradation products are volatile at the temperatures encountered in curlng the coat. The degradation products can be monomers, dimers or oligomers.
"Vaporize" means volatllization of the degradation 106Z5~8 products and their evaporation from the f`il~
Usually the polymers of ethylenically unsaturated monomers contain one or more monoethylenically unsaturated acid units.
Representative of these ethylenically unsaturated monomers are alkyl acrylates and methacrylates havlng 1 to 8 carbon atoms in the alkyl group~ styrene, 2-methyl styrene, vinyl toluene and glycidyl esters of 4 to 14 carbon atoms.
Representative of the monoethylenically unsaturated acids are acrylic acid, methacrylic acid, fumaric acld, itaconic acid and maleic acid (or anhydride).
The polymer of an ethylenically unsaturated monomer which produces a carbonaceous residue can be present as a coalescing agent in the composition at a concentration of about ~% through 60% by weight of total heat-stable polymer and residue producing polymer.
The heat-stable polymer composition may contain an oxidation catalyst composition.
An oxidation catalyst composition is any compo-~ition which contains one or more compounds which promotes~idation under the baking conditions required for fabri-cation of coated articles. The oxidation catalyst can promote oxidation either itself of through its decompo-sition products.
rncluded in this class of compounds are compounds containing:

chromium manganese copper bismuth cobalt cadmium iron molybdenum nlckel tin vanadium tungsten tantalum lithlum cerium 60dium.
thorium potassium calcium lead zlnc Preferred compounds are those whlch are produced by reaction of a metal from the following list (1) with an acid to form a salt compound of list (2).
(1) Metals bismuth lead cerium manganese cobalt nickel iron (2) Salts acetate octoate caprate oleate caprylate palmitate isodecanolate ricinoleate linoleate ~oyate naphthenate stearate nitrate tallate.

More preferred oxidatlon catalyst compounds ~re:
cobalt octoate ; cerium octoate maganese octoate ~ron octoate bismuth octoate nickel octoate lead octoate.
The concentratlon of the ~etal compound ln the lo composltion will be dictated by the nature of the compound, fabricating baklng conditions, amount of colorant, etc. In the general case, the compound læ present at a concentration hlgh enough to provide an amount o~ metal equal to 0.01 through 5 parts per hundred of heat-stable polymer.
Preferably the range is .1-1% metal.
The heat-stable polymer composition can be pigmented or unpigmented. Any pigment or combination of pigments ordinarily used ln this sort of composition can be used.
Ty~ical of these pigments are titanium dioxideg aluminum oxid~, ~lllca, cobalt oxide, iron oxide, etc. The total amount of pigment ordinarily present is at concentrations of up to 40%
by weight of the total solids in the composition.
The composition of this invention can contain mica particles, mica particles coated with pigment, and glass and metal flakes. These particles and flakes have an average longest dimension of 10 to 100 micronsO prefer-ably 15-50 microns, with no particles of flakes having a longest dimension of more than about 200 microns. Particle and flake size is measured optically against a standard.

~;2SS8 The mica partlcles coated with pigment preferred for use are those described in U.S. Patent 3,087,827 granted to Klenke and Stratton, and U.S. Patents 3,087,828 and

3,087,829 granted to Linton.
The mica particles described in these patents are coated wlth oxides or hydrous oxides of titanium, zirconium, aluminum, zinc, antimony, tin, iron, copper, nickel, cobalt, chromium, or vanadium. Titanium dioxide coated mica is preferred because of its availability. Mixtures of coated micas can also be used.
Representative of metal flake which can be used are aluminum flake, stainless steel flake, nickel flake, and bronze flake. Mixtures of flake can also be used.
The mica particles, coated mica particles, or glass and metal flake are ordinarily present in coating compositions at a concentration of about 0.2-20%, by weight of total solids.
~ he composition can also contain such conventional additives as Plow control agents, surfactants, plasticizers, coalescing agents, etc., as seem necessary or desirable.
These additives are added for reasons, in ways and in amounts known to artisans.
The amount of total solids in the composition will be governed by the substrate to which the composition is to be applied, method of application, curing procedure, and like factors. Ordinarily, the composition will contain 10%
through 80% by weight of total solids, but preferably 30%-50~.

1~

lOtiZ558 The antioxidant compositlon must lnclude one or more antioxidant compounds and a suitable carrler and can include color enhancers, viscosity builders or thickeners, wetting agents, pigments, decomposable resins and polymers, heat-stable resins and polymers, neutralizers, liquid carriers, and other ad~uncts.
Color enhancers are heat-unstable organic compounds which decompose to produce colorants thus enhancing the con-trast between decorative pattern and background. Examples of color enhancers are sugar, styrene, starch, fatty acid, and glycerides.
Polytetrafluoroethylene and other heat~stable poly-mers are examples of viscosity builders or thickeners. Pre-ferably the same heat-stable polymer utllized in the coating composition is utilized as the viscosity builder or thickener.
Examples of pigment are carbon black, iron oxide, cobalt oxide and titanium dioxide. When pigment is present in the antioxidant composition, at least an equal amount, preferably three t~ ten times as much, of heat-stable polymer will, preferably, also be present.
An antloxidant i8 any compound that opposes oxida-tion under fabrication baking conditions which are required for manufacture of heat-stable polymer coated articles. The antloxidant can oppose oxidation either by itself or through its decomposition or oxidation products. All of these com-pounds should yield at least .01 parts by weight~ based on sollds and expressed as the acid, of the correspondlng free 6Z~5~3 acids or anhydrides when the compound is decomposed and/or oxldized during fabrlcation baking. The preferred yield range is .1 to 1 part by welght.
Preferred antioxidants are compounds contain~
lng phosphoruQ, ~ulfur, boron or any comblnatlon of the above. The most common examples include the ortho-, meta-, pyro- acid~; neutral and basic salts; esters and generally thelr organlc derlvatlves includlng organo-metalllc derlvatives.
More preferred antioxidants are phosphoric acid, it~ decomposable salts containing ammonla or amines, 2-ethyl-hexyl diphenyl phosphate, magnesium glycerophosphate, calcium glycerophosphate, and iron glycerophosphate.
There must be elther a colorant in the heat-stable polymer composltion or a color enhancer in the antioxldant composltion when the antioxldant compound ltself doe~ not supply, aQ part o~ lts decomposltiofi products, a color enhancer.
m e antioxldant is dlssolved or dispersed in suit-2Q able carrler~ for the partlcular oxidation catalyst.
An antloxldant can also be present within the heat-stable polymer coatlng composition. The antioxidant of the coating composition can elther be the same or different from the antloxldant u~ed in the antloxidant composition.
The antioxldant co~positlon can be applied by any conventlonal method o~ applying in~. m e preferred method~ are to apply the antioxidant composition by "intaglio" orrset, e.g., uslng a TAMPOPRINI~ machine sold by Dependable Machine Co., Inc., or silk screening.
The heat-stable polgmer coatlng compositlon is * denotes trade mark ~A

~ )62558 applied to a thickness Or about 0.5-5 mils (dry) and baked for a tlme and at a temper~ture ~ufficient to fu~e or cure the heat-stable polymer being used.
The baklng temperature range of the process is dependent mainly upon which heat-stable polymer composltlon 18 utillzed. The process of this lnvention is utlllzable upon any conventionally used substrate. The substrate mQy be coated with a primer prior to the application of the oxida-tion catalyst co~positlon. me substrate 18 preferably pre-treated`prior to the application of any ooating composition.
Pre-treatment methods lnclude flame-spraying, frlt-coating, grit-blasting, ~nd acid- or alkali-treatlng. A metal sub-strate i8 preferably pre-treated by grit-blasting, by ~lame-spraying o~ a metal or a metal oxide, or by irlt-coatlng, although the compoxltlon can be applied successfully to phosphated, chromated or untreated metal. A glass sub-strate is preferably grit-blasted or frlt-coated.
A primer compositlon, i~ desired, can be applled either under or over the oxldation catalyst compositlon. m e primer composltion can be applied in any of the customary ~ay~, whlch include spraying, roller coating, dipping, and doctor blading. Spraying ls generally the method Or choice.
The prlmer composit~on can be any conventionally used primer coating, for example, a Rillca-perfluorocarbon primer.
Included in the process are varlous sequences of applying the compositions to the substrate, ror example, (l) first the antioxldant composition, and then the coating compositlon;

1062~58 (2) first the coating composition, and ther.
the a~tioxidant composition;
(3) first the prLmer composition, then the antioxidant composition, and then the coating composition;

(4) first the antioxidant composition, then the primer composition, and then the coating compo-sition; or

(5) first the primer composition, then the coating composition, and then the antioxidant composition.
The process of this lnvention is useful for any article that may use a heat-stable polymer sur~ace; examples are cookware, especially fry pans, bearings, valves, wlre, metal foil, boilers, pipes, ship bottoms, oven liners, lron ~oleplates, waffle irons, ice cube trays, snow shovels, saws, files and drills, hoppers and other industrial con-tainers and molds.
The following example is illustrative of the invention. A11 parts are by weight unless otherwise stated.

Prepare a heat-stable polymer composition as follows:
(a) Add, slowly, 100.66 parts by weight of deionized water to 657 parts by weight of an aqueous dis-persion of polytetrafluoroethylene containing

6~ by weight isooctylphenoxypolyethoxyethanol.
(b) Add, slowly and with stirring, to the product of (a) 115.75 parts by weight of an aqueous disperslon, 40% by weight solids, of a methyl methacrylate/ethyl acrylate/methacryliç acld 1~6Z558 polymer having a monomer welght ratio of 39/57/4.
(c) Prepare a black mill base by mixing and then pebble mllling:
carbon20 parts by weight alumlnosilicate pigment 10 parts by weight sodium polynaphthalene sul~onate3 part~ by welght water67 parts by welght (d) Prepare a titanlum dioxlde dispersion by mixing and pebble milling:
tltanium dioxide45 parts by welght deionized water 54.5 parts by weight sodium polynaphthalene ~ulfonate - .5 p~rt by welght (e) Prepare a cobalt oxide dlspersion by mixing and pebble milling:
cobalt oxlde ~ 45 parts by weight delonized water 55 parts by weight (f) Add in brder, slowly and with stirring, to the product of (b):
the black mill base10.72 parts by weight the titanium dioxide dispersion 81.21 parts by weight and the cobalt ox~de dispersion 9.74 parts by weight (g) Prepare a solvent-surfactant by mixing together:
triethanolamine 25.88 parts by weight toluene 46.36 parts by weight butyl carbitol 15.63 parts by weight oleic acid 12.13 parts by weight (h) Add slowly, w~th stlrring, 109.83 parts by weight of the solvent-surfactant to the product o~ (f).
(i) Prepare a phosphoric acid composition consisting o~:
pho~phoric acid (85%) l part by weight and triethanolamine 5 parts by weight (~) Add a sufficient amo~nt o~ the phosphoric acid composition to the product of (g) to produce a coating composition containin~ hos~horic acld ccmpoæition, Prepare ~our dlfferent antioxldant composltlon~ (A.C.) as follows:
A.C. (l) 10% by welght ammonium sulfamate in deionized water A.C. (2) 10% by welght boric acld in delonlzed water.
A.C. (3) lO~ by weight ammonium sulfate in delonized water A.C. (4) 10% by weight ammonium phosphate in deionized water.
Prepare two aluminum panels by frit-coating. Prime coat the panels with the following silica-fluorocarbon primer to a thickness of 0~3 mil ~dry) and dry in air.
Prepare the silica-fluorocar~on primer compo-sition as follows:
PARTS BY
(a) Mix toge~her WEIGHT
Polytetrafluoroethylene (PTFE) aqueous dispersion, 60% solids 478.76 Deionized water 130.23 1~2558 PARTS BY
W~IGHT
Colloidal silica 801, 30% so~ld~ in water (Ludo~ A~, sold by E. I. du Pont de Nemours and Company 327.18 (b) ~i~ separately TRITON X-100* (lsooctyl-phenoxypolyethoxyethylene nonionic surfactant sold by Rohm and Haas Co.) 17.52 Toluene 34.56 Butyl carbitol (diethylene glycol monobutyl ether acetate) 13.36 Sllicone solutlon (Dow Cornlng DC~801* Siiicone 60~ solids ln xylene) 34.56 Add 85.52 pdrts o~ (b) to (a) in a s~all ~tream, wlth stirring, over a 2-3 minute perlod. To this add, with ætirring PARTS BY
WEIGHT
Titanium dioxide disper~ion (45% ~olld~ dispersion in water) 35.46 Channel black dispersion (22% solids dispersion in water) .5 Stir ~or 10-20 minutes.
Draw ~our lines, u~ing a di~ferent antloxidant composition for each line, on bo~h pan~ls. Allo~ the anti-oxldant compositions to dry.
Spray the coating compositlon of (~) to a thickne6s of 1 mil (dry) on both panels and dry in air.
Place the air-dried panel~ into an oven at 430C.
Remove one pa~el after it ha6 boen at 430C. ~or 5 minutes.
Remove the other panel a~ter it ha~ been at 430C. for 15 minute~.

* denotes trade mark - ~ - 16 -The panels' background color remains the same while the areas over the lines are considerably darker than the background.

Prepare a cbating composition as follows:
(a) Add slowly, with stirring, 31.50 parts by weight of an aqueous dispersion, 40~ solids, ~f a methyl methacrylate/ethyl acrylate/meth-acrylic acid terpolymer having monomer weight r~tios o~ ~9/57/4 to 143.6 part~ by welght Or an aqueous dispersion o~ 60% by welght polytetrafluoroethylene, contalning q% by weight isooctylphenoxypolyethoxyethanol.
(b) Add slowly, with stlrring, to the product of (a), 2.0 parts by weight of a black mill base consisting of:
carbon 20% by weight aluminosilicate pigment 10% by weight sodium polynaphthalene ~ulfonate 3% by weight water 67% by weight.
(c) Add slowly, wlth stirring, to the product of (b), 5.3 parts by weight of a complementary m~l base consisting of:
titanlum dioxide 45 parts by weight delon~zed ~Jater ~4.5 parts by weight sodium polynaphthalene ~ul~ona'e - .5 parts by weight.

1~6255F~

(d) Add slowly, with stirring, to the product of (c), 25.7 parts by weight of a solvent-surPactant-oxidation catalyst solution prepared as follows:
mix together in order trlethanQlamine 5.5 parts by weight oleic acid ~.3 parts by weight toluene 11.1 parts by wei~ht - butyl carbitol3.8 parts by weight cerlum octo~te (12% metal content by weight in 2-ethyi hexanoic acid)1.5 parts by weight cobalt octoate - (12% metal content by weight in mineral splrits)0.5 parts by welght Prepare an aluminum panel by frit-coating and prim-lng according to the dlrections in Example 1.
Prepare an antioxidant composition consist1ng of:
phosphorlc acid (85~) 1 part by wei~ht triethanolamine 5 parts by weight.
Stamp the antioxidant composition, arranged ln a decorative pattern, upon the aluminum panel.
Spray the coating composition produced by (d) onto ~he aluminum panel to a thickness of 0.7 mil (dry).
Dry the coated panel in air.
Place ths alr-dried panel into an oven at 430C.
When the temperature of the panel has been 430C. for 5 minutes, remove the panel.

1~6255~3 . The ~rea over the antioxldant compositiDn is dark while the other ~reas of the coating are light thereby produc-ing a dark decorative pattern on a light background.

Prepsre an aluminum panel by frlt-coating and priming as in Example 1.
Prepare an antloxldsnt compo~ltlon conslstlng of:
(a) 2% Carbopol~ 934 ln water (a thlckening resin con-sistine of carbox~ vlnyl polymers of extremely high molecular weight sold by L. F. Goldrich Chemical Company) lB parts by weight (b) phosphoric acid (85%) in water 1 part by weight triethanolamine 5 parts b~ weieht 2 parts by weight - (c) black mill base made by mixing and pebble-milling:
triethanolamine

7.00 parts by weight oleic acid 3.28 parts by weight butyl carbitol 4,23 parts by weight toluene 12.56 parts by welght deionized water 59.39 parts by weight 106ZSS~

channel black 15.69 parts by weight aluminosilicate pigment 7.84 parts by weight 0.3 parts by weight (d) an aqueous dispersion of polytetrafluoroethylene, 60% solids, containing 6%
by weight of 1sooctylphenoxy-polyethoxyethanol 1.5 parts by welght Prepare a coating composition as in Example 1.
Use a polyester silk screen having 15% open surface and thread diameter of 34 microns to place the antioxldant composition, in a decorative design, onto the aluminum panel.
Spray the coatlng composition onto the aluminum panel to a thickness of 0.7 mil (dry).
Dry the coated panel in air.
Place the air-dried panel into an oven at 430C.
When the temperature of the panel has been 430C. for 15 minutes, remove the panel.
The area over the antioxidant composition is dark while the other areas of the coating are light3 there-by producing a dark decorative pattern on a light background.

Prepare an alumillum panel by frit-coating and priming as ln Example 1.
Prepare a coating composition as in Example 1 Prepare an antioxidant composition consisting of:

l~Z55~3 (a) phosphoric acld (85%) in water 1 part by welght trlethanola~ine 5 parts by weight 193.0 parts by ~t.
(b) i~ooctylphenoxypoly-ethoxyethanol9.65 pArts by wt.
(c) polytetrafluoroethylene powder 96.50 parts by wt.
(d) iron oxide pigment4.83 part~ by wt.
(e) cobalt oxide plgment4.83 part~ by wt.
Using "Intaglio" ofiRet printing technique, place the a~tioxidant composition, in a decoratlve pattern, onto the aluminum panel.
Spray the coating co~position onto the aluminu~
panel to a thlckness o~ 0.7 mll (dry).
Dry the coated panel in alr.
Place the air-dried pan~l lnto an oven at 430C.
When the te~perature o~ the panel ha~ been 430C. ror 15 minutes, remove the panel.
The area over the antioxidant compositlon iB
dark whlle the other area~ Or the coating are light, there-by producing a dark decoratlve pattern on a light background.

Prepare an aluminu~ panel by frit-coating as in Example 1.
Prepare a p~lmer composition as ~ollow~:
PARTS BY
WEIGHT
(a) m e polya~ide acid amine salt solution Or Example 1 o~ Canadian Applicatlon No. 244 959 of T.P. Concannon, flled February 3, 1976 (containing 18% of rurfuryl aicohol and 10~
Or N-methyl-pyrolidone) 151.8 PARTS ~Y
WEIGHT
(b) Furfuryl alcohol 15.2 (c) Deionized water 520.0 (d) White plgment dispersion (made by ball-milllng a mixture of TiO 46 Parts Wat~r 46 "
Triethanolamine/
oleic acid mixture 2/1 8 n )52.6 (e) PTFE dispersion in ~ater (60% solids) 222.5 (~) LUDOX AM (a colloidal sillca soid by E. I. du Pont de Nemours and Company) 2g.8 Spray the primer composition on the frit-coated alumlnum panel to a thickness Or .3-mil (dry) and then 2~ dry in air.
Prepare an antioxidant compositlon as in Example 4.
Uslng "Intaglio" o~fset printing technique, place the antioxld~nt composition, in a decorative pattern, onto the aluminum panel.
Prepare a coating composition as follows:
PARTS BY
WEIGHT
(a) Mix together slo~ly, with stirring, PTFE dlzperslon in water -60% sollds by weight con-taining 6% by ~eight isooetylphenoxypolyethoxy-ethanol 324.25 Black mill base con~l~ting of Carbon - 20% by wt.
Aluminosillcate pigment - 10% " "
Sodlum polynaphthanene-sulfonate - 3%
Water - 67% " " 4.5 lO~;ZSS8 PARTS BY
WEIGHT
(b) Slowly wlth vigorous stirrlng add to the product of (a) TiO coated mica (A~FLAIR* NF-140-D, sold by E. I. du Pont de Nemours and Company) 4.00 (c) Premix the following and then add slowly with stirring to the product of (b) Triethanolamine - 11.35 parts Oleic acld - 7.15 "
Toluene _ 25.35 "
Butyl carbltol - 8.5 n Cerlum octoate (23% metal content) - 1.80 "
Cobalt octoate (18% metal content) - .75 " 54.90 (d) Add slowly, wlth stlrring, an aqueou~ dlspersion, 40~ sollds of a methYl methacrylate/ethyl acrylate/methacryllc acld terpolymer havin~ monomer weight ratios of 39/57/4 71.1 (e) Add slowly, with stirring, to the product o~ (d) Delonized water 24.25 Spray the coating composition onto the aluminum panel to a thickness o~ 0.7-mll (dry).
Dry the coated panel in alr.
Place the air-dried panel lnto an oven at 430C for 15 minutes, then remove the panel.
The area over the antio~ldant composition ls dark while the other areas o~ the coatlng are light, thereby producing a dark decorative pattern on a light back~round.

* denotes trade mark

Claims (3)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
1 A process for preparing a decorative coating on a substrate, comprising the following steps, with (a) and (b) performed in any order:
a. applying to a substrate a composition comprising 1. a heat-stable polymer; and 2. a colorant; and 3. a liquid carrier; and b. applying to a substrate, in a decorative pattern, a composition comprising

1. an antioxidant; and 2. a liquid carrier;
and then heating the resulting coating to the heat-stable poly-mer fusion temperature wherein the heat stable polymer composition is stable at temperatures above 300°C and the heat-stable poly-mer is a silicone, polysulfide, polymerized p-hydroxy-benzoic acidJ a polysulfide, polymerized p-hydroxy-benzoic acid, a polysulfone, a polyimide, a polyamide, a polysulfonate, a poly-sulfonamide, a fluorocarbon polymer, or a mixture thereof.

2. The process of claim 1 wherein the composition of (a) contains an antioxidant.
3. The process of claim 1 wherein the composition of (b) contains a colorant.
4. The process of any one of claim 1, claim 2 and claim 3 wherein the antioxidant composition contains a compound or mixture of compounds containing phosphorus, sulfur, boron or mixtures thereof.
5. The process of any one of claim 1, claim 2 and claim 3 wherein the antioxidant is phosphoric acid, its decomposable salts containing ammonia or amines, 2-ethylhexyl diphenyl phosphate, magnesium glycerophosphate, calcium glycerophosphate, iron glycerophosphate or mixtures thereof;
and the heat-stable polymer composition is further comprised of a colorant.
6. The process of any one of claim 1, claim 2 and claim 3 wherein the antioxidant composition further contains color enhancers, viscosity builders or thickeners, wetting agents, pigments, decomposable or heat-stable resins and polymers, neutralizers, liquid carrier or mixtures thereof;
said antioxidant contains a compound or mixture of compounds containing phosphorus, sulfur, boron or mixtures thereof;
7. The process of any one of claim 1, claim 2 and claim 3 wherein the antioxidant is phosphoric acid, its decomposable salts containing ammonia or amines, 2-ethylhexyl diphenyl phosphate, magnesium glycerophosphate, calcium glycero-phosphate, iron glycerophosphate or mixtures thereof; and the antioxidant composition is further comprised of a color enhancer.
8. The process of any one of claim 1, claim 2 and claim 3 wherein the heat-stable polymer is a fluorocarbon polymer.
9. The process of any one of claim 1, claim 2 and claim 3 wherein the heat-stable polymer is a hydrocarbon poly-mer completely substituted with fluorine atoms or a combination of fluorine atoms and chlorine atoms.
10. The process of any one of claim 1, claim 2 and claim 3 wherein the heat-stable polymer is polytetrafluoro-ethylene, a copolymer of tetrafluoroethylene and hexafluoro-propylene or mixtures thereof.
11. The process of any one of claim 1, claim 2 and claim 3 wherein the colorant is carbon black, a carbonaceous residue, or mixtures thereof.
12. The process of claim 1 wherein the heat-stable polymer composition contains an oxidation catalyst composition.

13. The process of claim 12 wherein the oxidation catalyst composition contains an oxidation catalyst compound which is a compound or mixture of compounds containing one or more of the following:

14. The process of claim 13 wherein the oxidation catalyst composition contains a mixture of a compound containing cerium and a compound containing cobalt.
15. The process of claim 13 wherein the oxidation catalyst is a compound or mixture of compounds produced by reaction of a metal from list (1) with an acid to form a salt compound of list (2):

16. The process of claim 12 wherein the oxidation catalyst is:
Cobalt octoate Cerium octoate Manganese octoate Iron octoate Bismuth octoate Nickel octoate or Lead octoate 17. The article bearing a decorative pattern produced by the process of any one of claim 1, claim 2 and

claim 3.