Note: Descriptions are shown in the official language in which they were submitted.
3 ~ .~J ~ ~
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PROCESS FOR COATING METAL AND PLASTIC
TO IMPART WOOD-LIKE APPEARANCES
This is a continuation-in-part of Serial No. 103,440,
filed September 30, 1987, which, in turn, is a
continuation-in-part of Serial No. 940,904, filed
December 10, 1986.
The present invention is directed to a method for
coating metal or plastic to render it capable of
receiving wood-grain printing inks and conventional
wood stains, while also concealing joints and other
imperfections.
In the construction uses of metal or plastic, there
are many applications in which the appearance of wood
would be desired. For example, on exposed surfaces
of doors, window frames, and the like, it would be
desirable to have the appearance and texture of
wood. Moreover, to have a decorative effect, would
be desirable to be able to ~tain a wood-like surface
to a desired color, such as walnut, rosewood, and the
like, then cover it with a protective coating such as
varnish or other conventional clear coating.
It is therefore an object of the present invention to
provide compositions which are useful for coating
metal or plastic surfaces to impart the grainy
appearance of the natural wood.
,
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-2-
It is a further object of the present invention to
provide novel coatings for metal or plastic surfaces
which accept conventional wood stains.
These and other objects will be apparent from the
following description and preferred embodiments.
The present method utilizes a basecoat composition
for covering a metal or plastic surface comprising a
combination of resins, pigments, solvents, and
; additives for suspension, dispersion, wetting,
thickening, flowing and anti-marring. A printing
composition is also provided comprising resins,
pigments, solvents, and tinting and wetting agents.
The method according to the present invention
comprises the steps of applying a novel liquid
basecoat onto a metal or plastic surface, evaporating
volatile solvents to form a solid coating, and
applying a novel ink composition in a wood grain
pattern onto the solid coating.
Generally, metal or plastic surface will be first
coated with a liquid basecoat composition according
to the present invention then dried to remove the
volatile solvents. The drying is preferably
performed with h~-at in a conventional oven, but other
evaporative methods may be utilized particularly, if
a pla~tic surface is being coated in order to avoid
warpage or other deformation. Then a grain ink
formulation may be applied in a pattern to simulate a
wood grain using a conventional roller having a wood
grain pattern using the inks described herein.
Apparatus for performing these functions are
conventional and known in the art.
-3-
- The basecoat formulation according to the present
invention comprises the following components: alkyd
resins, other resins, absorption pigments, other
pigments, suspension agent, dispersing agent, wetting
agent, thickener, anti-marring agent, flow agent,
and solvents.
In general, the basecoat formulation comprises:
% volume
alkyd resins 4.66 - 5.70
10 styrene-allyl alcohol copolymer ~.66 - 5.70
solvents 41.56 - 50.78
chlorinated paraffin3.79 - 4.63
tripentaerythritol4.25 - 5.19
ammonium polyphosphate powder 11.25 - 13.75
15 melamine resin 3.92 - 4.80
wetting agent 0.24 ~ 0.30
deodorant 0.25 - 0.31
ethyl hydroxy ethyl cellulose 8.06 - 9.86
pecan shell flour1.01 - 1.23
20 resimene resins 1.80 - 2.20
flow agent 0.04 - 0.06
suspension agent0.11 - 0.13
titanium oxide white piqment 1.17 - 1O43
vinyl resins 1.32 - l.fi2
25 cellulose acetate0.96 - 1.18
dioctyl phthalate0.64 - 0.78
inorganic yellow pigment0.10 - 0.12
talc 0.06 - 0.08
cellulose acetate butyrate 0.14 - 0.18
~he solvents preferably comprise 1.27-1.55% (of total
volume of the composition) toluene, 4.45-5.43% methyl
ethyl ketone, and 3.21-3~93% acetone, in addition to
mixtures of various other volatile liquids such as
alcohols, hydrocarbons, and the like.
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4--
A particularly preferred basecoat composition useful
for coating wood contains the following (percentages
given by volume).
Alkyd resin5.18 Resin Guardsman
RJ-100 Soln.5.18 Suspension Agent Monsanto
Xylene 26.91 Solvent
Solvent #1503.30 Solvent Chemtech
- Chlorowax4.21 Anti-mar agent
Tripentaerythritol 4.72 Absorption pigment
Phoschek P/30 12.50 Absorption pigment Monsanto
Superfine Melamine 4.36 Vehicle resin Melamine Chem.
Collidisperse .27 ~e~ting agent Troy
Deodorant .28 Guardsman
EHEC solution 8.96 Thick~ner Hercules
Pecan shell flour 1.12 Absorption pigment
(45 Micron)
Industrial toluene 1.41 Solvent
Resimene #955 2.00 Vehicle resin Monsanto
Lactimon .05 Flow a~ent BYK Mallinckrodt
MPA 2000X .12 Suspension agent NL
RHD 6X Titanium 1.30 White pigment Tio-~ide
Methyl ethyl ketone 4.94 Solvent
Acetone 3.S7 Solvent
Lacquer diluent 5.40 Dispersing solvent Ashland
VAGH Vinyl1.47 Resin Union Carbide
Cellulose acetate 1.07 Solvent
Dioctyl phthalate .71 Solvent
2444-XF Yellow .11 Inorganic Pigment Pfizer
Nytal 400 .07 Talc Vanderbilt
Jaysol Anhydrons .17 Solvent Eastman
MIBK .47 Solvent
1 Sec. CAB 531-1 .16 Vehicle resin Eastman
100 . 00
In the above preferred formulation, in addition to
the alkyd resins, the other resins include Melamine
(melamine resins sold by ~elamine Chemicals),
Resimene, a butylated urea resin sold by Monsanto;
and CAB ~cellulose acetate butyrate, sold by
Eastmanj, all commercially available resins. Such
other resins also include polyester resins,
including water extended polyesters, polystyrene,
vinyl resins including polyvinylacetate,
polyvinylchloride, vinylchloride-vinylacetate
copolymers and the like; polyamide resins, polyurea
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resins, and acrylic resins; phenolic resins, maleic
resins, coumerone-indene resins, urea-formaldehyde;
melamine-formaldehyde resins; epoxy resins, silicone
resins, ionomer resins, acetal resins, polyethylene,
polypropylene, hydrocarbon resins, rubber
derivatives, polycarbonate resins, phenoxy resins,
~luorol plastics, 6tyrene-butadiene resins,
polyurethane resins, furane resins, polysulfone
resins, pentaerythritol resins, ester gum,
copalesters, and the like. Natural resins which may
be used include shellac, rosin copal resins, damar
resins, manila resins and the like.
Absorption pigments which may be utilized include
tripentaerythritol, Phoschek P/30 (an ammonium
polyphosphate white powder sold by Monsanto), and
pecan shell flour, or any combination thereof. The
composition will also contain other pigments, which
may be inorganic or organic. These pigments include
RHD-6X Titanium, Yellow 2444-XF, Nytal 400 (a talc).
The base coat composition will also contain
suspension agents, dispersing agents, wetting agents,
thickeners, anti-marring agents, flow agents and
` optionally, deodorant additives to alleviate any
offensive smells caused by the base coat. Suspension
agents include MPA-2000X (sold by NL Chemicals), and
RJ-100 (styrene-allyl alcohol copolymer), both made
by Monsanto. Preferred dispersing agents include a
lacquer used as a diluent. Preferred wetting agents
included Collidisperse, made by Troy Chemical. A
preferred thickener includes EHEC (ethyl hydroxy
ethyl cellulose) Solution (~ercules). Any readily
available anti-marring agent may be used such as
Chlorowax (a chlorinated paraffin sold by Diamond
Shamrock). A ~low agent such as Lactimon (BYK
Mallinckrodt~ may be utilized.
.
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Typical solvents include xylene, Solvent #150
(Ashland), toluens, methyl ethyl ketone, acetone,
cellulose acetate, dioctyl phthalate, Jaysol
Anhydrons (Eastman), and MIBK (methyl isobutyl
ketone). Other ~olvents may include turpentine,
diapintine, pine oil, petroleum spirits, naphtha,
mineral spirits, methyl and ethyl alcohol, toluol,
benzol, xylol, ethyl acetate, amyl acetate, and the
like. The several portions of any vehicle used in
comparing one of the decoratiYe coatings are
generally composed of the same basic materials
although they may have varied amounts of thinners,
solvents, fillers and the like so as to vary their
viscosities and other physical properties, but there
may be a combination of unrelated resins used on the
same panel to provide texture and growth lines.
The pulverized pecan nut shell flour utilized in the
base coat composition as an absorption pigment will
be in the form of a ~ine powder, typically grain size
of about 42 to 46 microns (preferably 45 average
microns). Preferably pecan shell flour will be used.
The amount of the volatile solvents and esters which
are utilized will be of the kind in an amount
su~ficient to dissolve and/or suspend the various
components in a uniform liquid suspension material.
It is desirable that the solvents comprise some polar
solvents, such as acetone and cellulose acetate, and
some non-polar solvents such as xylene, and slightly
polar solvents such as ketones. Other higher
molecular weight solvents may also be utilized such
as petroleum distillates, esters, all of which are
commercially available.
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The particular proportions of the various components
used may be generally in the proportions given above.
It will ~e understood however, that various
modifications in proportions and components may be
utilized without departing from the scope of the
present invention.
In addition to the various pigments mentioned above,
the base coat may contain various typical inorganic
pigments useful for wood grain such as those iron
pigments ranging in color from yellow through red,
reddish brown, brown to black, similar to khose found
in natural wood. These iron pigments include yellow
ocher~ raw and burnt sienna, and raw and burnt umber.
Other useful inorganic color pi~ments include chrome
yellow, cadmium sulfide, zinc yellow, cobalt blue,
ultramarine blue, iron oxide, chrome green, chromium
oxide green, chromium hydroxide green, lamp black
carbon, and white pigments such as titanium dioxide,
titanium calcium, zinc oxide, zinc sulfide, antimony
oxide, lithopone, etc. Organic pigments may also be
utili~ed such as toluidine red, phthalocyanine blue
and green, VanDyke brown, alizarin, madder lake,
lythol red, etc.
After applying the base coat to the metal or plastic
surface, it is dried, ~or exampl , in a conventional
oven to remove the volatile solvents, thereby forming
a hardened base coat. An ink formulation may then be
applied to the base coat with a roller having a wood
grain pattern. The ink formulation comprises:
resins, pigments, absorption pigments, tinting
agents, wetting agents, and solvents.
The resins utilized in the above ink ~ormulation
include acrylic resins such as Joncryl 74, BALAB,
UCAR-SCT 100. The pigments include various pigment~
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utilized to simulate wood grain colors, as described
above and include speci~ically yellow 8g5-000-1801
(Nuodex), burnt umber (I-347), red oxide 895-1003
(Harshaw), Mearlin silk white (an iridescent
pi~ment). As an absorption pigment Phoschek P/30 may
be utilized. As a tinting agent a tint paste such as
Benzidine yellow (W-1041) may be utilized. A wetting
agent such as glycol ether (PM) is used. Various
solvents may be u~ilized such as DMAE (Union
Carbide), water and ethylene glycol.
The pigments which are utilized in the ink
formulation will depend upon the color o~ the wood
grain desired. The pigments must, of course, impart
a color to the ink formulation which is different
~rom the color of the dried base coat in order to
provide contrast. Usually, colorants which impart
yellow or brown tones to the base coat will be
useful. Typically, the base coat, after application
; of the ink formulation, will be stained with a
conventional wood stain, which usually enhances the
contrast between the base coat and the ink.
In general, the ink formulation comprises:
% volume
acrylic resins 47.02 - 57.46
` 25 latex resins 1.74 - 2.12
ethylene glycol 2.09 - 2.55
DMAE 0.52 - 0.64
water 4.64 - 5.67
glycol ether 5.77 - 7.05
yellow pigment 5O60 - 6.84
tint paste 4.41 - 5.39
burnt umber pigment15.09 - 18.45
red oxide pigment 0.71 0.87
iridescent pigment 0.20 - O.24
ammonium polyphosphate powder 2.21 - 2.70
~J ~ ~3 l,~ t.
A typical ink formulation may comprise the ~ollowing
(% by volume):
Manufacturer
Joncryl 74 52.24 Acrylic resin Johnson &
Johnson
BALAB 3056A .73 Resin (latex) Uitco
Ethylene glycol2.32 Solvent
DNAE .58 Solvent
Tap Water 5.15 Solvent
UCAR SCT100 1.20 Resin (latex) Union Car~ide
Glycol Eth~r PM6.41 ~etting agent Ashland
895-000-1801 Yellow 6.22 Pigment Nuodex
W-1041 Benzidine
. Yellow 4.90 Tint paste Harshaw
I-347 Bt. Umber16.77 Pigment Harshaw
895-1003 Red Oxide .79 Pi~ment Nuodex
Mearline Silk White .22 Iridescent pigment Mearl
Phos Chek P/30 fine 2.45 Absorption pigment Monsant~
100 . 00
After application of the graining ink formulation and
air drying, the final product may be utilized as is,
or stained with a conventional wood stain, then
coated with a conventional varnish or other clear
preservative.
Having described the specific embodiments of the
: invention, other modifications and variations will be
: apparent to those of ordinary skill in the art, which
variations and modifications are intended to be
within the scope of the present invention.
