Coating processes – Nonuniform coating
Reexamination Certificate
2002-10-07
2004-07-06
Parker, Fred J. (Department: 1762)
Coating processes
Nonuniform coating
C427S271000, C427S274000, C427S277000
Reexamination Certificate
active
06759088
ABSTRACT:
BACKGROUND TO THE INVENTION
The present invention is concerned with a decorative method and a blank for a decorator's tool and in particular a decorative method for providing a grained appearance on a substrate.
Grain imitation techniques are known in which a scumble glaze is applied to a painted wood substrate, the scumble glaze being applied in a streaky discontinuous manner to give the appearance of natural graining. Currently used techniques however are very time consuming and require considerable expertise, such as that of a craftsman, to create a desired natural grain appearance. They do not therefore appeal to amateur (that is, “do-it-yourself”) painters, who represent an increasingly important part of the market.
Similarly, it is known to create imitation woodgrains on a surface using specialised tools to create the grain finish. Normally, at least two tools are required in order to achieve the desired effect. Existing tools consist of combs having teeth or the like which are used to establish a continuous streaked or grained appearance on a painted substrate, and a separate tool having a convex surface, with a series of concentric ridge formations on the convex surface, which can be used to selectively expose parts of the surface, so as to produce a simulated woodgrain appearance on the surface. Using separate tools to create the woodgrain finish suffers from a number of drawbacks. In addition, packaging of two separate tools in a box or the like requires extra packaging space and packaging material, which adds to the total cost of the product.
OBJECTS OF THE INVENTION
It is the primary object of the present invention to provide a method which will appeal to the amateur and alleviate some of the abovementioned problems.
It is a further object of the invention to provide a blank for a unitary, hand-holdable tool, suitable for use by both amateur and professional decorators in creating an imitation woodgrained finish on a surface.
SUMMARY OF THE INVENTION
According to a first aspect of the present invention, there is provided a method of providing a decorative coating for an opaque surface, which method comprises applying to said opaque surface a substantially continuous layer comprising an intimate mixture comprising a particulate (preferably non film-forming) material and an aqueous film-forming polymer binder, said particulate material and said layer both being lighter in color than said opaque surface, and discontinuously removing part of said layer (preferably in streaks) using a tool so as to selectively expose part of said opaque surface.
Any experienced professional or amateur painter will know, by judgement by eye and instinct, the difference between lighter and darker shades of color. However, if needed, guidance can be gained from the international system of color definition known as the Natural Color System (“NCS.”) The NCS system is described in the “ICI Colour Dimensions Colour Atlas” published by Imperial Chemical Industries P
1
c of London in 1986 (“Colour Dimensions” is a trademark of Imperial Chemical Industries). The NCS system defines color in terms of a cypher, the first two digits of which extend from 00 to 99 with 00 representing white (that is, the ultimate lightness) and 99 representing black, and the intermediate values from 01 to 98 representing increasingly darker shades. Lighter shades therefore have a lower pair of first digits. It is preferred that the particular material and the continuous layer have an NCS value at least 10 units lower than that of the surface.
DESCRIPTION OF PREFERRED EMBODIMENTS
The particulate material is typically an inorganic material, which may be hydrated, such as plaster (gypsum), clay or the like, or non-hydrated, such as chalk or titanium dioxide. When an inorganic material is used, it is advantageous that the intimate mixture used in the method according to the invention may be fire retardant.
Alternatively, an organic particulate material, such as hollow or alveolate beads of polystyrene or the like, or finely chopped fibers may be used. Suitable organic beads are described, for example, in European Patent Specification No. 0,113,435 B1, published Jun. 7, 1989. This European Patent Specification describes an aqueous paint having an improved “hiding quality.” The aqueous paint in the European reference consists essentially of pigmented vesiculated beads and opaque polymer particles in a ratio of 30/70 to 90/10, the proportion of opaque polymer particles being smaller at higher pigment volume concentrations. The particulate material is intimately mixed with the aqueous polymer binder, preferably together with thixotropising material, such as a polyurea adduct or bentonite clay, so as to provide thixotropic mixture.
It may be preferred that the intimate mixture further comprises reinforcing fibers which can serve to strengthen a resulting coating provided on the opaque surface.
Advantageously, the intimate mixture further comprises a drying retardant (a material which retards drying of the coating). The use of a drying retardant is beneficial in allowing the mixture to be applied as a substantially continuous layer and further allowing subsequent removal thereof before substantial drying of the layer has occurred.
A preferred drying retardant comprises a gel material. Examples of gels suitable for use as a drying retardant are cellulose-based products such as carboxymethyl cellulose, hydroxymethyl cellulose and methyl cellulose, acrylamide and acrylate polymers and copolymers, gelatin, polysaccharides, polyoxamers (polyoxyethylene-polyoxypropylene block copolymers), pectins and agar.
It is preferred that the aqueous polymer binder is translucent. Preferably the binder comprises an aqueous dispersion of particles of polymer which are capable of coalescing as the dispersion dries so as to form a film of polymeric material. Suitable polymers include polymers and copolymers of esters such as methyl, ethyl, propyl and hexyl esters of acrylic or methacrylic acids, optionally with acrylic or methacrylic acid or polymers, or copolymers of vinyl esters including vinyl acetate. Certain copolymers of these types are now available as aqueous solutions as opposed to dispersions.
The aqueous polymer binder may, in some cases, contain a minor proportion by weight of an organic solvent, which should be miscible with water. An example of such a solvent is an alcohol.
It is preferred that the intimate mixture comprises substantially equal amounts of an aqueous carrier, typically water, and the particulate material, the aqueous carrier and particulate material being present in excess of the polymer binder. A preferred intimate mixture comprises 4 to 6 parts by weight of the particulate material, 4 to 6 parts by weight of water optionally 0 to 2 parts organic (preferably alcoholic) co-solvent to assist film formation and 0.5 to 3 parts by weight of the aqueous polymer binder. In a particularly preferred embodiment of the present invention, wherein the intimate mixture further comprises a drying retardant substantially as hereinbefore described, the preferred intimate mixture includes 0.5 to 3 parts by weight of the drying retardant.
The opaque surface may be provided by wood, plastics, metal or the like, and it preferably has a darker color than the intimate mixture. In some embodiments it is preferred that the substrate comprises wood. The invention is particularly advantageous in enabling the production of an article having a grained appearance, such as that simulating limed oak, limed maple, limed ash or the like. The substrate may, for example, be timber, or a fiber board such as MDF (medium density fiber board).
Advantageously, the substrate comprises a building structure such as a wall panel, door, door frame, window frame, wainscotting or the like. Alternately the substrate may comprise a furniture component such as a fitted kitchen or bedroom unit, closet door, table, seat or the like. In some embodiments, the substrate comprises at least one generally planar surface which is required to have a grained appearance as d
Parker Fred J.
Schindler Edwin D.
LandOfFree
Decorative method using a blank for a decorator's tool does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Decorative method using a blank for a decorator's tool, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Decorative method using a blank for a decorator's tool will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3245536