Patent Application
20080060552
In the accompanying drawings, which form a part of the specification and are to be read in conjunction therewith:
Paint systems in accordance with exemplary embodiments of the present invention include a foundation base component and a top coat component. The foundation base component is a tintable color base or a clear base that is shaded or colored with color concentrates to match or substantially match the color of the top coat component. The foundation base component is preferably not a white foundation base or white primer that can affect or change the color of the top coat unless the color of the top coat is white. Instead, the foundation base component is tinted to match the top coat component to provide both the desired amount of hiding of colors or markings on the substrate to which the paint system is applied, and to enhance the brightness and hue of the color of the paint system.
The foundation base and the top coat are paints that are capable of forming films and generally contain a binder, a diluent, one or more color pigments and other additives including fillers. The binder eventually solidifies to form the dried paint. Depending on the type of binder, this solidification or hardening may be a result of a chemical reaction or curing (polymerization), evaporation, i.e., drying, or even cooling. In one embodiment, the binder dries to form a solid film when the diluent or solvent evaporates. In another embodiment, the binder is a polymer binder that solidifies during curing or polymerization. Typical binders include synthetic or natural resins such as acrylics, polyurethanes, polyesters, melamines, oils, or latex. Examples of suitable polymers include, but are not limited to, high molecular weight organic materials including polyacrylics, polymethacrylics, polyesters, polyurethanes and copolymers thereof. Alternatively, cured binder films are formed from crosslinkers, such as polyurethane or melamine resins, reacted with acrylic polyester or polyurethane resins, often in the presence of a catalyst which serves to make the curing reaction proceed more quickly or under milder conditions. These cured-film paints can be either solvent-borne or waterborne. Preferably, the binder used in the foundation base component is a polymeric binder.
In addition, other suitable waterborne paints are emulsions of solid binders in water. Upon evaporation of the diluent, the molecules of the binder coalesce to form a solid film. Such emulsion paints are also known as latex paints because the polymer is formed through an emulsion polymerization through which the monomers are emulsified in a water-continuous phase. Since the polymer is not soluble in water, the dried paint is water resistant. Other types of binders form films as a result of cooling. For example, encaustic or wax paints are liquid when warm, and harden upon cooling.
Suitable diluents are known and available in the art and are selected based upon the type of binder that is being used. Examples of diluents include, but are not limited to, organic solvents such as alcohols, ketones, esters, glycol ethers and combinations thereof. Other diluents include water and volatile low-molecular weight synthetic resins.
Other additives can be included in the foundation base component depending upon the application to which the paint is used or based upon desired qualities in the paint systems. These additives include, but are not limited to, catalysts, thickeners, stabilizers, emulsifiers, texturizers, adhesion promoters, flatteners (de-glossing agents), UV absorbers and hindered amine light stabilizers, dispersants, wetting agents, anti-settling agents and combinations thereof. The additives also include one or more fillers. In general, fillers serve to thicken the film, support its structure and simply increase the volume of the paint. Common fillers are inexpensive and inert, for example talc, lime, baryte and bentonite clay.
The foundation base component also includes at least one color pigment. Alternatively, the foundation base component contains a plurality of color pigments, both organic color pigments and inorganic color pigments. The color pigments are selected based upon the desired color in final dried paint. The color pigments are added to the foundation base material in an amount sufficient to provide the desired hiding or covering of the substrate to which the paint system is applied. More specifically, the amount of color pigments are sufficient to hide dark or multi-colored backgrounds, i.e., gray stripes on a white background, with the application of only the foundation base component and the top coat component. The color pigments are added to the foundation base component in an amount such that the volume ratio of organic color pigments to binder (Volume of Color Pigments/Volume of Binder) is at least about 0.10, preferably at least 0.15, and more preferably at least 0.20.
As stated above, the color pigments can be organic color pigments, inorganic color pigments or mixtures thereof. In one embodiment, the foundation base component includes at least one organic color pigment, and can contain a plurality of different organic color pigments, for example synthetic organic color pigments. Alternatively, the foundation base component includes a mixture of organic color pigments and inorganic color pigments. In this mixture, the majority of color pigments are organic color pigments. In one embodiment, the volume ratio of organic color pigments to inorganic color pigments in the foundation base component is at least about 0.5, preferably at least about 1.0, more preferably at least about 1.5, and can increase as high as desired. In fact, this ratio can be infinitely high for foundation base components that do not contain any inorganic color pigments. In general, a sufficient amount of organic color pigments are included in the foundation base component so that the organic color pigments represent at least about 8%, preferably at least about 15%, more preferably at least about 30% by volume of the dried film.
The inventive paint system also includes a top coat component that is applied over the foundation base component after it dries. The top coat component can include the same constituents, i.e., binders, diluents, color pigments and additives, as the foundation base component. The top coat component includes the same general formulation of binders, diluents and additives as the foundation base component or can include a different formulation. The top coat component can include both organic color pigments and inorganic color pigments. Suitable organic and inorganic color pigments are the same as for the foundation base component. Although the top coat component can contain both organic and inorganic color pigments, preferably, the top coat component contains primarily organic color pigments. In one embodiment, at least about 80%, preferably 85%, more preferably 90% by volume of all color pigments in the top coat component are organic color pigments. In addition, the ratio of organic color pigments in the foundation base component to the organic color pigments in the top coat component is at least about 2 times, preferably at least about 2.5 times, and more preferably more than 3 times. In order to facilitate adequate hiding of the substrate while achieving the desired color in the final paint system without substantial loss in color qualities such as brightness, the foundation base component and the top coat component are formulated to be substantially the same color.
The top coat composition is preferably opaque. As used herein, the term “opaque”, in reference to substrates, coatings, compositions that are made into coatings and the like (hereinafter referred to generally as coating(s), without intent to limit), including, but not limited to, solid and/or liquid states, means that the coating has an average transmittance of visible light, e.g., between about 380 nm and about 770 nm or alternately between about 400 nm and about 700 nm, of less than about 30% on a 3-mil drawdown film, preferably at least about 20%, more preferably at least about 10%. The average transmittance referred to herein is typically measured for incident light normal, i.e., approximately 90°, to the plane of the coating and can be measured using any known light transmission apparatus and method, e.g., a UV-Vis spectrophotometer. Both the foundation paint and the top coat paint form opaque films on the substrate to be covered.
General descriptions of paints and components thereof can be found in commonly-owned, co-pending U.S. patent application Ser. Nos. 11/290,667, filed on Nov. 30, 2005, Ser. No. 11/384,183, filed on Mar. 16, 2006 and 11/323,622, filed on Dec. 30, 2005. These applications are incorporated by reference herein in their entireties.
Both synthetic and natural organic pigments can be used. Suitable organic color pigments include, but are not limited to, azo (monoazo, disazo, β-naphthol, naphthol AS, benzimidazolone, disazo condensation etc.), metal-complex, isoindolinone and isoindoline, phthalocyanine, quinacridone, perinone and perylene, anthraquinone, diketopyrrolopyrrole (DPP), dioxazine, quinophthalone and fluorescent pigments.
In general, the main categories of suitable organic color pigments can be classified as azo pigments and non-azo or polycyclic pigments. Suitable pigments are disclosed in U.S. Pat. No. 5,985,987, which is incorporated herein by reference in its entirety. These suitable pigments include organic pigments such as,
Other pigments include organic-inorganic hybrid pigments such as TICO pigments (commercially available from Heubach). Examples of TICO pigments are
Both synthetic and natural inorganic pigments can be used. Suitable inorganic color pigments include, but are not limited to, pigments in elementary form, i.e., carbon and aluminum, oxide and oxide hydroxide pigments, e.g., TiO2, Fe2O3 and FeO(OH), oxide mixed-phase pigments, e.g., 4BiVO43Bi2MoO6, (Co,Ni,Zb)2TiO4 and Cu(Fe,Cr)2O4, sulphide and sulphate pigments, e.g., ZnS, BaSO4 and ZnS+BaSO4, chromate and chromate molybdate mixed-phase pigments, e.g., PbCrO4+PbSO4 and PbCrO4+PbSO4+PbMoO4, complex salt pigments, for example iron blues are complex salts of ammonium and sodium ferriferrocyanides, and silicate pigments, e.g., ultramarines (Na7 Al6 Si6 O24 S3).
Suitable inorganic pigments, as disclosed in the '987 patent, include
In one exemplary embodiment, a paint system in accordance with the present invention consists essentially of the foundation base component that contains at least one organic color pigment representing at least about 8% of the volume when dry, and a top coat component applied over the foundation base component and containing one or more organic color pigments at an amount of at least about 80% of all color pigments by volume, and formulated such that the ratio of organic color pigments in the foundation base component to organic color pigments in the top coat component is at least about 2.
The present invention is also directed to methods for covering substrates using paint systems formulated in accordance with the present invention. Suitable substrates include, but are not limited to, metals, such as steel, iron and aluminum, and plastics, such as thermoplastics, like polycarbonates, polyacrylates and especially thermoplastic polyolefins, papers, wood and wood products, cardboard, plaster, dry-wall or plasterboard and combinations thereof. The paint system can be applied to the substrate using any suitable method known and available in the art including, brushing, rolling and spraying. In one embodiment, a single coat or layer of a foundation base component formulated in accordance with the present invention is applied to the substrate. The foundation based component can be allowed to partially or completely dry. A single coat or layer of the top coat component formulated in accordance with the present invention is then applied over the foundation base component.
While it is apparent that the illustrative embodiments of the invention disclosed herein fulfill the objectives of the present invention, it is appreciated that numerous modifications and other embodiments may be devised by those skilled in the art. Additionally, feature(s) and/or element(s) from any embodiment may be used singly or in combination with other embodiment(s) and steps or elements from methods in accordance with the present invention can be executed or performed in any suitable order. Therefore, it will be understood that the appended claims are intended to cover all such modifications and embodiments, which would come within the spirit and scope of the present invention.
The following Examples are merely illustrative of certain embodiments of the invention. The following Examples are not meant to limit the scope and breadth of the present invention, as recited in the appended claims.
A one gallon aluminum can was filled with Benjamin Moore Details Eggshell 5244X (115 oz.) and Benjamin Moore Details Colorant 229Y1(Organic Yellow) (15 oz.). The formulation was mixed in a mechanical shaker for 6 minutes. Using a 3-mil drawdown bar, a drawdown was applied onto a black and white Leneta drawdown card (Form 18B). A drawdown is the application of paint evenly to a card such as Leneta drawdown cards. In this Example, Form 18B is a black and white card comprising four areas: two sealed white areas, one unsealed white area and one sealed black area Form 18B is a penopac chart, which measures opacity and penetration. Leneta cards are known in the art. In all the Examples discussed herein Form 18B is used as the substrate.
The drawdown was dried overnight and the contrast ratio (C/R) of the dried film was measured with a spectrophotometer. A second drawdown was then made on the top of the first coat to obtain the C/R of the two-coat dry film. Third and fourth drawdowns were also made, and the corresponding C/Rs of the three-coat and four-coat dry films were determined. The C/Rs of the one-coat, two-coat, three-coat, and four-coat dry films are shown in
As shown in
A color foundation finish (100 gallons) was prepared using the following quantities of grind and letdown ingredients:
In Example 2, no inorganic color pigment is used and the organic color pigments represent 11.7 vol % of the foundation paint and 30.8 vol % of the dried foundation film.
The C/R on a 3-mil drawdown was measured for one coat of color foundation Example 2, and for one coat of Example 2 plus a top coat of Example 1. As shown in
A color foundation finish (100 gallons) was prepared using the following quantities of grind and letdown ingredients:
In Example 3, no inorganic color pigment is used. The organic color pigments represent 19.3% by volume of the foundation paint and 42.5% of the dried film. The C/R of the foundation coat on a 3-mil drawdown is 99%.
A yellow pigment paste was prepared using the following ingredients:
In a separate container, a color foundation finish (100 gallons) was prepared using the following quantities of grind and letdown ingredients:
In Example 4, the organic to inorganic color pigment ratio is 2.49 by volume. The organic color pigments represent 17.9% by volume of the foundation paint and 35.0% of the dried film. The C/R of a 3-mil drawdown of Example 4 is 99.2%.
Conventional color primers using titanium dioxide have a “whitening effect” because only a small amount of color pigments, especially organic color pigments, are used in the tints. The color foundation in Example 4 uses a large amount of organic color pigments that overcome the whitening effect from titanium dioxide. It is a tintable yellow foundation finish that can be tinted to many different shades required by top coats. Table 1 shows this yellow foundation finish of Example 4 (124 oz.) tinted with various BM Details Colorants (4 oz.).
The color foundation coat uses a significantly larger amount of organic pigments than those in a conventional first coat and at least twice as many organic pigments by volume than the top coat. Table 2 lists the organic pigment levels in the conventional first coat, color foundation coat, and top coat.
Color foundation coat/top coat paint systems (with the colors of Yellow (BM color palette 2023-10) and Bright Lime (BM color palette 2025-10)) were compared with conventional approaches using two top coats of BM Details, C2 commercial color primer with a top coat, and BM Deep Base Primer (216) with Benjamin Moore Regal top coat (319). The paints using conventional approaches were obtained from Benjamin Moore and C2 retail stores.
The following components were used in the first and second coats of Example 5A:
The following components were used in the first and second coats of Example 5B:
For Example 5C, the first coat contained a Color Primer Accent Color System (C2085) tinted to BM Color 2025-10 at a C2 retail store (see www.C2color.com). The second coat (top coat) contained a C2 Interior Eggshell Acrylic Enamel (C4285) tinted to BM Color 2025-10 at a C2 retail store.
For Example 5D, the first coat contained a BM Regal Deep Base Primer 216 tinted to color P702 in BM Color palette as a recommended primer. The second coat (top coat) contained BM Regal 319 4B tinted to BM Color 2025-10.
In Example 5D, the organic color pigment volume for the first coat is 1.6% in paint and 6.16% in dried film. The organic color pigment volume for the second coat is 2.17% in paint and 5.70% in dried film.
For Example 5E, two coats of BM Details Eggshell were tinted to BM Color 2023-10 as in the second coat of Example 5A. In example 5E, the organic color pigment volume is 1.78% in paint and 4.23% in dried film.
For Example 5F, two coats of BM Details Eggshell were tinted to BM Color 2025-10 as in the second coat of Example 5B. In Example 5F, the organic color pigment volume is 1.77% in paint and 4.21% in dried film.
A contrast ratio of at least 99%, or preferably 99.5%, for two or more coats of certain bright and high chroma colors, is required to have hiding power on black/white substrate without being detected by trained eyes. Examples of these bright and high chorma colors are organic yellow and other light colors tinted from organic yellow, such as light orange and light blue.
Conventional approaches, such as Examples 5E and 5F, would need more than two 3-mil thick coats to have the required hiding power on black/white substrate of Form 18B. Two-coat paints of a conventional primer and a top coat, such as Example 5C in which the primer basically has about the same organic pigment content as in the top coat, also would not have adequate hiding power on black/white substrate.
Other conventional approaches include adding high hiding power color pigments (e.g., dark green, blue, black or some other dark color pigments in the primer as the first coat. For example, a better hiding organic pigment, such as green is used in Example 5D to improve hiding. Although the C/R is sufficient to hide black/white substrate, the difference between the color of primer and top coat is increased. Consequently, one top coat is not sufficient to hide the color of the underlying primer so as to obtain the desired color.
For Color 2023-10, the Delta E value between the color foundation/top coat paint system (from Example 5A) and two same-colored top coats (from Example 5E) is 0.12 as shown in
In order to achieve such a close match, the reflectance curve of the color foundation coat and the reflectance curve of the foundation and top coat should have a similar pattern.
The color of this primer/top coat paint system in Example 5D also significantly deviates from the color of top coat as shown in
When paint films are applied using brushes or rollers, the paint films are not as smooth as in drawdowns. Brush marks from brushes or bumps form rollers may be formed. The color of the primer, which has a very different color than the top coat, may not only be seen through the top coat but also may have a non-uniform appearance. Additional one or more top coats are required to have the right and uniform color.
A conventional color finish was formulated using the following ingredients:
A tintable red color foundation, which contains both inorganic pigment (TiO2) and red organic pigment, was prepared using the following quantities of grind and letdown ingredients:
The contrast ratios (C/Rs) of Examples 6 and 7, measured on a Leneta card, are listed in Table 4. Two coats of conventional Example 6 have a C/R of 93% and will not have sufficient hiding power to hide black/white substrate. The red foundation of Example 7 with a top coat improves the C/R to 99.8%.
Example 7 is a tintable red foundation finish that can be tinted with color concentrates to obtain desired colors. In Table 5, Example 7 (124 oz.) was tinted with various Benjamin Moore Details Color Concentrates (4 oz.). The C/Rs were measured on a 3-mil draw-down.
C2 Primer (C2085) and C2 Interior Acrylic Eggshell Enamel (C4284) were obtained from a C2 retail store and tinted to the Color 2000-10 in Benjamin Moore Color Palette.
A Deep Base Primer 216 tinted to the Color P-500 in BM Color Palette was used as the first coat. Benjamin Moore Regal Eggshell was tinted to 2000-10 was used as the second coat. The following components were used in the first and second coats of Example 8B:
For example 8C, the red color foundation of Example 7 was used as a first coat. Benjamin Moore Details Eggshell 524 was tinted to 2000-10 and was used as second coat. The following components were used in the first and second coats of Example 8C:
The C/Rs were measured on dried drawdowns using a 3-mil drawdown bar, and are listed in Table 6. The color foundation/top coat was the only paint system that provided adequate hiding for two coats. C2 paints with three coats still did not provide sufficient hiding power.
The color difference between the red foundation coat/top coat (Example 8C) and the same two top coats has a Delta E of 0.26. This small Delta E is reflected in the reflectance curves in
C* is the distance of a color in the color space to the center. It is a measure of the chroma of a color. A large value of C* indicates a high chroma color, or a clean color as referred to in the paint industry. Organic pigments typically provide higher chromatic colors than inorganic pigments of the same colors. Organic yellow and red pigmented paints may have C* of at least 70 and well over 100, depending on the amount and type of other color or extender pigments in paints.
C* of color foundation/top coat systems and multiple top coats were measured with a spectrophotometer on dried films. As shown in Table 7, the C* of a color foundation/top coat system is almost identical to that of multiple top coats of same colors. The color foundation/top coat system retains the high chroma of those colors from organic color pigments. In addition, the L is the indication of the brightness of a color. Table 7 shows that the brightness of the color is not decreased by the foundation coat.
While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of illustration and example only, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention.
Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the appended claims and their equivalents. It will also be understood that each feature of each embodiment discussed herein, and of each reference cited herein, can be used in combination with the features of any other embodiment. All patents and publications discussed herein are incorporated by reference herein in their entirety.
