Waterborne nonstick coating composition including silicone resin and silicone fluid

Abstract

The present disclosure is directed to a curable coating composition comprising a silicone or polysiloxane resin, a nonstick silicone component in the form of a polydimethylsiloxane such as a silicone fluid or gum, a surfactant, and water. The polysiloxane resin may comprise a selected formulation of siloxane monomer residues. The surfactant may be a tri-block surfactant or an ethylated / propoxylated sorbitan. The coating composition may be substantially free of fluoropolymers.

Description

WATERBORNE NONSTICK COATING COMPOSITION INCLUDING SILICONE RESIN AND SILICONE FLUIDCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application No. 63 / 847,803 entitled “WATERBORNE NONSTICK COATING COMPOSITION INCLUDING SILICONE RESIN AND SILICONE FLUID”, filed on July 21, 2025, and U.S. Provisional Application No. 63 / 760,982 entitled “WATERBORNE NONSTICK COATING COMPOSITION INCLUDING SILICONE RESIN AND SILICONE FLUID”, filed on February 20, 2025, the entire disclosures of which are incorporated by reference in its entirety.FIELD

[0002] The present disclosure relates to a nonstick coating composition with high molecular weight comprising a silicone or polysiloxane resin and a nonstick silicone component in the form of a silicone fluid.BACKGROUND

[0003] Fluoropolymers have been utilized for nonstick coatings for many years.Fluoropolymer coatings generally have low surface energy which enables long lasting nonstick performance. Fluoropolymers are also available in waterborne dispersions enabling viscosities for spray and roller application as well as additive compatibility. Due to increased consumer and regulatory scrutiny of the use of fluoropolymers in coating compositions, a fluoropolymer-free nonstick coating is desired.SUMMARY

[0004] The present disclosure provides a waterborne, curable coating composition. The coating composition includes a silicone or polysiloxane resin, a nonstick silicone component in the form of a polydimethylsiloxane, a surfactant, and water. The polysiloxane resin may comprise a selected formulation of siloxane monomer residues. The polydimethylsiloxane may be a silicone fluid or silicone gum. The surfactant may be a tri-block surfactant or anethylated / propoxylated sorbitan. The coating composition may be substantially free of fluoropolymers.

[0005] The polysiloxane resin comprises the following siloxane monomer residues:(I) [R1Si(O)? / 2]a, wherein:a is the molar fraction of (I) and is from 30-60, based on the total moles of polysiloxane resin; andR1is a C1-C30 linear or C3-C30 cyclic alkyl group;(II) optionally [R2R3Si(O)]b, whereinb is the molar fraction of (II) and is from 0-30, based on the total moles of polysiloxane resin; andR2and R3are each independently a C1-C30 linear or C3-C30 cyclic alkyl group, or a Ce or C7 aryl group;(III) [R4Si(O)3 / 2]c, wherein:c is the molar fraction of (III) and is from is 0-70, based on the total moles of polysiloxane resin; andR4is at least one of an aryl group, a vinyl group, or a combination thereof; (IV) optionally [Si(O)4 / 2]d, whereind is the molar fraction of (IV) and is from is 0-20, based on the total moles of poly siloxane resin.

[0006] The resin includes 20 mol% or less of monomers (II), based on total moles of monomers (I), (II), (III), and (IV) in the poly siloxane resin. Further, the resin includes less than 90 mol% aryl groups R4, based on total moles of groups R1, R2, R3, and R4. The coating composition includes particles of the polysiloxane resin emulsified by the surfactant and dispersed within the water.

[0007] The present disclosure further provides a method of coating an article of cookware or bakeware. The method includes applying to a surface of the article the coating composition of the present disclosure and curing the coating.

[0008] The present disclosure provides an article of cookware or bakeware, comprising a surface coated with a coating derived from the coating composition of the present disclosure.DETAILED DESCRIPTION

[0009] The present disclosure provides a non-stick coating composition comprising a silicone resin and a silicone fluid / gum. The coating composition may be substantially free of fluoropolymers.

[0010] I. Definitions

[0011] For purposes of the following detailed description, it is to be understood that the disclosure may assume various alternative variations and step sequences, except where expressly specified to the contrary. Moreover, other than in any operating examples or where otherwise indicated, all numbers expressing, for example, quantities of ingredients used in the specification and claims are to be understood as being modified in all instances by the term "about." For example, numerical ranges provided for weight percentages of components or amounts of components added should be construed as being modified by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0012] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard variation found in their respective testing measurements.

[0013] Whereas particular examples of this disclosure have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present disclosure may be made without departing from what is defined in the appended claims.

[0014] Also, it should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of "1 to 10" is intended to include all sub-ranges from (and including) the recited minimum value of 1 to the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10.

[0015] The use of the singular includes the plural and plural encompasses singular, unless specifically stated otherwise. In addition, the use of "or" means "and / or" unless specifically stated otherwise, even though "and / or" may be explicitly used in certain instances.

[0016] “Resin solids” refers to the solid components that make up the binder or filmforming components of the composition. As used herein, a weight percentage based on “resin solids” refers to an amount of a component based on a total weight of the binder or film-forming components of a composition.

[0017] ‘Siloxane monomer residue” refers to a monomer including a silicon atom with one or more R-Si-0 linkages (wherein R is an organic group) that is capable of reacting with other such monomers via hydrolysis and condensation to form polysiloxane polymers with Si-O-Si linkages. The oxygen atom may be bound to a hydrozable group (not shown in the siloxane monomer residue formula) such as a hydrogen, methoxy, ethoxy, propoxy, or chloro group.

[0018] “Polymer” or “resin” as used herein refers to a molecule made of repeating monomer units. The monomer units may be covalently bonded to form the polymer / resin chain.

[0019] II. Coating Composition

[0020] The present disclosure provides a non-stick coating composition comprising a silicone resin; a nonstick silicone component; a surfactant; and at least one solvent, such as water.

[0021] A. Silicone or Polysiloxane Resin

[0022] The coating composition may comprise a silicone resin, also referred to herein as a polysiloxane resin. The silicone resin may be a film forming component that impart thermal resistance and prevent bulk coating degradation. The silicone resin may have a relatively low surface energy that gives the coating composition nonstick properties when used in combination with silicone fluid / gum.

[0023] The silicone resin may be prepared via hydrolysis and condensation of at least two different types of siloxane monomers, water, solvent, and a catalyst. The silicone resin may be the reaction product of two, three, or four siloxane monomers, such as any of the siloxane monomers listed below.

[0024] The silicone resin may comprise end groups. The end groups may be at least one of methoxy, ethoxy, hydroxyl, and a combination thereof.

[0025] The silicone resin may comprise a weight average molecular weight from 1000 g / mol, 1500 g / mol, 1800 g / mol, 2000 g / mol to 6000 g / mol, 8000 g / mol, 10000 g / mol, or 20000 g / mol, or any range using any two of the foregoing values as endpoints, such as 1000 g / mol to 20000 g / mol, 1500 g / mol to 10000 g / mol, 1800 g / mol to 8000 g / mol, or 2000 g / mol to 4000 g / mol, as determined by gel permeation chromatography using polystyrene polymer beads for calibration standards.

[0026] The coating composition may comprise an amount of silicone resin from 10 wt. %, 20 wt. %, or 30 wt. % to 50 wt. %, 60 wt. %, or 90 wt. %, or any range using any two of the foregoing values as endpoints, such as 10 wt. % to 90 wt. %, 20 wt. % to 60 wt. %, or 30 wt. % to 50 wt. %, based on the total “wet” weight of the coating composition.

[0027] The cured coating may comprise an amount of silicone resin from 50 wt. %, 55 wt. %, or 60 wt. % to 70 wt. %, 80 wt. %, or 90 wt. %, or any range using any two of the foregoing values as endpoints, such as 50 wt. % to 90 wt. %, 55 wt. % to 80 wt. %, or 60 wt. % to 70 wt. %, based on the total “dry” weight of the cured coating.

[0028] i. Siloxane Monomer Units

[0029] The silicone resin may be formed as the reaction product of multiple siloxane monomers. The term “siloxane monomer” may be used interchangeably with “silicone,” “monomer unit,” and “silicone monomer.”

[0030] The siloxane monomer units may be described according to the degree of oxygen substitution, or functionality, on the central silicon.Table A: Siloxane Monomer Types

[0031] The silicone resin comprises monomers where R may be primarily phenyl and methyl, as these afford resistance to degradation at the typical in-use temperatures for cookware and bakeware (150 - 300 °C). Additionally, phenyl groups and D siloxane monomer units may be necessary for thermal resistance of the coating composition.

[0032] Suitable trifunctional siloxane monomers (T units) used to produce the polysiloxane polymer may include methyltrimethoxy silane, methyltriethoxy silane, phenyltrimethoxy silane, phenyltriethoxy silane, ethyltrimethoxy silane, propyltrimethoxy silane, ethyltriethoxy silane, octyltriethoxy silane, and propyltriethoxy silane.

[0033] Suitable difunctional siloxane monomers (D units) used to produce the polysiloxane polymer may include dimethyldimethoxy silane, diphenyldimethoxy silane, diphenyldiethoxy silane, methylphenyldimethoxy silane, dimethyldiethoxy silane, diphenyldiethoxy silane, and methylphenyldiethoxy silane.

[0034] The silicone resin may comprise the following siloxane monomer residues:(I) [R1Si(O)3 / 2]a;(II) [R2R3Si(O)]b;(III) [R4Si(O)3 / 2]c ; and(IV) optionally [Si(O)4 / 2]<i;wherein:[R1Si(O)3 / 2]a is a T unit, and R1is a Ci-C3o (inclusive of all integers such as 1, 2, 3, 4, 5, ... up to 30, or any range including any two of the foregoing as endpoints) linear or C3-C3o(inclusive of all integers such as 3, 4, 5, ... up to 30, or any range including any two of the foregoing as endpoints) cyclic alkyl group;[R2R3Si(O)]b is a D unit, and R2and R3are each independently a C1-C30 (inclusive of all integers such as 1, 2, 3, 4, 5, ... up to 30, or any range including any two of the foregoing as endpoints) linear or C3-C30 (inclusive of all integers such as 3, 4, 5, ... up to 30, or any range including any two of the foregoing as endpoints) cyclic alkyl group, or a Ct, or C7 aryl group;[R4Si(O)3 / 2]c is a T unit, and R4is at least one of an aryl group, a vinyl group, and combinations thereof; and[Si(O)4 / 2]d is a Q unit.

[0035] The silicone resin may comprise a mole fraction of methyl T units ([R1Si(O)3 / 2]a) from 30, 35, or 40 to 45, 50, or 60, or any range including any two of the foregoing values as endpoints, such as 30 to 60, 35 to 50, or 40 to 45, based on the total moles of the siloxane units in the silicone resin.

[0036] The silicone resin may comprise a mole fraction of phenyl T units ([R4Si(O)3 / 2]c) from 0, 10, or 20 to 30, 40, or 70, or any range including any two of the foregoing values as endpoints, such as 0 to 70, 10 to 40, or 20 to 30, based on the total moles of the siloxane units in the silicone resin.

[0037] The R4groups may be present in the silicone resin in an amount as little as 5 mol %, as little as 10 mol %, as little as 20 mol %, as little as 30 mol % or as high as 40 mol %, as high as 50 mol %, as high as 60 mol %, as high as 70 mol %, or any range using any two of the foregoing values as endpoints, such as from 5 mol % to 70 mol %, from 10 mol % to 60 mol %, 20 mol % to 50 mol %, or from 30 mol % to 40 mol %, based on the total moles of R1, R2, R3, and R4.

[0038] The silicone resin may comprise a mole fraction of D units ([R2R3Si(O)]b) from 0, 1, or 5 to 10, 15. or 30, or any range including any two of the foregoing values as endpoints, such as 0 to 20, 1 to 15, or 5 to 10, based on the total moles of the siloxane units in the silicone resin.

[0039] The D units may be present in the silicone resin in an amount less than 30 mol %, less than 15 mol %, less than 10 mol %, or less than 5 mol %, or any range using any two of the foregoing values as endpoints, such as 5 mol % to 30 mol %, or 10 mol % to 15 mol %, of D units, based on the total moles of siloxane monomer units in the silicone resin.

[0040] The silicone resin may comprise a mole fraction of Q units ([Si(O)4 / 2]d) from 0, 1, or 5 to 10, 15, or 20, or any range including any two of the foregoing values as endpoints, such as 0 to 20, 1 to 15, or 5 to 10, based on the total moles of the siloxane units in the silicone resin.

[0041] The silicone resin may be essentially free, substantially free, or completely free of M siloxane monomer units. By essentially free of M units, it is meant that the silicone resin may comprise less than 1 mol % of M, based on the total moles of siloxane units in the silicone resin. By substantially free of M units, it is meant that the polysiloxane polymer may comprise less than 0.5 mol % of M, based on the total moles of siloxane units in the silicone resin. By completely free of M units, it is meant that the silicone resin may comprise less than 0.1 mol % of M units, based on the total moles of the siloxane units in the silicone resin.

[0042] B. Nonstick Silicone Component

[0043] The coating composition may comprise a nonstick silicone component. The nonstick silicone component may be a silicone fluid or a silicone gum wherein, as used herein, the term “silicone fluid” generally encompasses silicone gums which may be considered a subset of silicone fluids. The silicone fluid or gum may be a silicone-based polymer that is used to increase the non-stick properties of the coating composition. These components may provide a smooth surface to the cured coating, reducing the adhesion of food or other substances to the substrate.

[0044] The nonstick silicone component may be dispersed throughout the coating composition. The nonstick silicone component may migrate to the surface of the coating composition to provide nonstick properties. It is advantageous to control the rate of migration to provide continuous long lasting nonstick.

[0045] The nonstick silicone component may have a high molecular weight. Coating compositions with higher molecular weight nonstick silicone components may also comprise an increased amount of solvent to lower the viscosity than coatings with lower molecular weight silicone fluid / gum.

[0046] The coating composition may comprise an amount of nonstick silicone component from 0.5 wt. %, 1 wt. %, or 5 wt. % to 10 wt. %, 15 wt. %, or 20 wt. %, or any range using any two of the foregoing values as endpoints, such as 0.5 wt. % to 20 wt. %, 1 wt. % to 15 wt. %, or 5 wt. % to 10 wt. %, based on the total “wet” weight of the coating composition.

[0047] The cured coating may comprise an amount of nonstick silicone component from 1 wt. %, 5 wt. %, or 10 wt. % to 15 wt. %, 18 wt. %, or 20 wt. %, or any range using any two of the foregoing values as endpoints, such as 1 wt. % to 20 wt. %, 5 wt. % to 18 wt. %. or 10 wt. % to 15 wt. %, based on the total “dry” weight of the cured coating.

[0048] Suitable silicone fluids may include poly dimethylsiloxane (PDMS). The silicone fluid may have a viscosity from 25 cSt, 50 cSt, 100 cSt, 500 cSt, or 1000 cSt to 2000 cSt, 4000 cSt, 8000 cSt, 10,000 cSt, or 15,000 cSt, or any range using any two of the foregoing values as endpoints, such as 25 cSt to 15.000 cSt, 50 cSt to 10,000 cSt, 100 cSt to 8000 cSt, 500 cSt to 4000 cSt, or 1000 cSt to 2000 cSt at 25°C ± 0.2°C, as determined according to ASTM D4283-98(2015). Further, the silicone fluid may have an atomic mass from 1000 AMU, 2000 AMU, or 5000 AMU to 10,000 AMU, 40,000 AMU, or 80.000 AMU, or any range using any two of the foregoing values as endpoints, such as 1000 AMU to 80,000 AMU, 2000 AMU to 40,000 AMU, or 5000 AMU to 10,000 AMU, as determined according to gel permeation chromatography-GPC calibrated using polystyrene beads.

[0049] Suitable silicone gums may include polydimethylsiloxane (PDMS), dimethyl silicone gum, methyl vinyl silicone gum, phenyl silicone gum, and mixtures thereof. The silicone gum may have a viscosity from 1,000,000 cSt, 5,000,000cSt, or 10,000,000 cSt to 15,000,000 cSt, 18,000,000 cSt, or 20,000,000 cSt, or any range using any two of the foregoing values as endpoints, such as 1,000,000 cSt to 20,000,000 cSt. 5,000,000 cSt to 18,000,000 cSt, or 10,000,000 cSt to 15,000,000 cSt at 25°C ± 0.2°C, as determined according to ASTM D2983 (2023). Further, the silicone fluid may have an atomic mass from 100,000 AMU, 500,000 AMU, or 1,000,000 AMU to 10,000,000 AMU, 15,000,000 AMU, or 20.000,000 AMU, or any range using any two of the foregoing values as endpoints, such as 100,000 AMU to 20,000,000 AMU, 500,000 AMU to 15,000,000 AMU, or 1,000,000 AMU to 10,000,000 AMU, as determined according to gel permeation chromatography-GPC calibrated using polystyrene beads.

[0050] C. Surfactant

[0051] The coating composition may comprise at least one surfactant. The surfactant may improve the dispersion and stability of the components within the coating composition.Specifically, the surfactant may enhance wetting and spreading and improve adhesion to the substrate. Additionally, the surfactant may aid in emulsification of the silicone resin and / or the silicone fluid / gum in the water-borne or aqueous media.

[0052] The coating composition may comprise an amount of surfactant from 0.1 wt. %, 0.5 wt. %, or 1 wt. % to 2 wt. %, 5 wt. %, or 10 wt. %, or any range using any two of the foregoing values as endpoints, such as 0.1 wt. % to 10 wt. %, 0.5 wt. % to 5 wt. %, or 1 wt. % to 2 wt. %, based on the total “wet” weight of the coating composition.

[0053] The cured coating may comprise an amount of surfactant from 0.5 wt. %, 1 wt. %, or 5 wt. % to 10 wt. %, 15 wt. %, or 20 wt. %, or any range using any two of the foregoing values as endpoints, such as 0.5 wt. % to 20 wt. %, 1 wt. % to 15 wt. %, or 5 wt. % to 10 wt. %, based on the total “dry” weight of the cured coating.

[0054] Suitable surfactants may include, but are not limited to the following: alkyl sulphates (e.g., sodium lauryl sulphate); ether sulphates; phosphate esters; sulphonates; and their various alkali, ammonium, amine salts; aliphatic alcohol ethoxylates; alkyl phenol ethoxylates (e.g. nonyl phenol polyether); ethylated / propoxylated sorbitans, salts and / or combinations thereof.

[0055] Surfactants in the coating composition may include non-ionic triblock copolymers. As used herein, a structural unit of triblock copolymer-based non-ionic surfactant refers to a compound of Formulas la and lb below.Formula lawherein x is the number of repeat units of an ethylene glycol monomer from 120-150, y is the number of repeat units of a propylene glycol monomer from 40-60, and z is the number of repeat units of an ethylene glycol monomer from 120-150.Formula lbwherein x is the number of repeat units of a propylene glycol monomer from 40-60, y is the number of repeat units of an ethylene glycol monomer from 120-150, and z is the number of repeat units of an propylene glycol monomer from 40-60.

[0056] The coating composition may comprise an ethylated / propoxylated sorbitan, derived from the dehydration product of sorbitol and modified with ethylene oxide and / or propylene oxide groups, as a surfactant. The ethylated / propoxylated sorbitan may comprise a compound of Formula II.<" <Formula IIwherein w is the number of repeat units from 1-17, x is the number of repeat units from 1-17, y is the number of repeat units from 1-17, and z is the number of repeat units from 1-17, and w+x+y+z=20.

[0057] Surfactants of Formula II may create oil in water emulsions of the silicones within the coating composition.

[0058] D. Solvent

[0059] The coating composition may be a waterborne coating composition in that the mobile phase of the composition comprises water, providing water dilatability and enabling low viscosity of high viscosity materials.

[0060] The coating composition may comprise at least one solvent, such as a nonaqueous solvent, an organic solvent, an inorganic solvent, and combinations thereof.

[0061] i. Water

[0062] The solvent of the coating composition may include water only, or one or more non-aqueous solvents in combination with water.

[0063] The coating composition may be a waterborne composition. By water-borne it is meant that the mobile phase of the liquid coating is water, providing water dilutability and enabling low viscosity of high viscosity materials.

[0064] The coating composition may comprise an amount of water from 10 wt. %, 15 wt. %, or 20 wt. % to 30 wt. %. 40 wt. %, or 50 wt. %, or any range using any two of the foregoingvalues as endpoints, such as 10 wt. % to 50 wt. %, 15 wt. % to 40 wt. %, or 20 wt. % to 30 wt. %, based on the total “wet” weight of the coating composition.

[0065] ii. Non-Aqueous Solvents

[0066] The coating composition may comprise one or more non-aqueous solvents.

[0067] Suitable non-aqueous solvents may include xylene, butanol, toluene, methyl ethyl ketone, methyl isobutyl ketone, acetone, butyl acetate, dipropylene glycol monomethyl ether, methoxy propoxy propanol, methoxy propyl acetate, and methyl soy esters. Organic solvents may be included in the coating composition to aid in compatibility of the components and lower the viscosity of the coating composition to enable spray and / or roller coating application.

[0068] The coating composition may comprise an amount of a non-aqueous solvent from 0 wt. %, 10 wt. %, or 20 wt. % to 30 wt. %, 40 wt. %, or 50 wt. %, or any range using any two of the foregoing values as endpoints, such as 0 wt. % to 50 wt. %, 10 wt. % to 40 wt. %, or 20 wt. % to 30 wt. %, based on the total “wet” weight of the coating composition.

[0069] III. Properties of the Coating Composition

[0070] The coatings of the present disclosure may be substantially free, essentially free, or completely free of fluorine-containing components.

[0071] Fluorine-containing components may include per / polyfluoroalkyl substances (PFAS), such as fluoropolymers, fluorine-containing oligomers and / or fluorine containing small molecules.

[0072] By substantially free in relation to fluoropolymers, is meant that the coating composition may comprise less than 5 wt. % of fluoropolymers based on the total weight of the “wet” coating composition. By essentially free in relation to fluoropolymers, is meant that the coating composition may comprise less than 1 wt. % of fluoropolymers based on the total weight of the “wet” coating composition. By completely free in relation to fluoropolymers, is meant that the coating composition may comprise less than 0.01 wt. % of fluoropolymers based on the total weight of the “wet” coating composition.

[0073] IV. Method of Application and Curing

[0074] A. Substrate

[0075] The coating composition of the present application may be applied to a surface of a substrate. Suitable substrates may include metals, ceramic materials, plastics, composites, and minerals. Suitable metals may include typically electrolytic chromium coated steel (ECCS),aluminized steel, stainless steel, aluminum, and carbon steel, for example. Suitable plastics and composites include high melting point plastics and composites, such as plastics having a melting point higher than the cure temperature of the coating formulation, including polyester, polypropylene, ABS, polyethylene, carbon fiber epoxy composites, and glass fiber epoxy composites, for example. Suitable minerals include micas, basalts, aluminas, silicas, and wollastonites, marble and granite, for example. The coating composition may be used to coat cook and bakeware, such as a pan, skillets, griddles, pots and the like, or other cooking articles which are exposed to heat in use.

[0076] The coating compositions may be used to coat non-cookware articles, such as rollers, molds, conduits and fasteners, which require a non-stick or release property and / or which are exposed to heat in use.

[0077] The coating compositions may be applied directly to the surface of a substrate, or may be applied over one or more undercoats, such as a primer, which are in turn applied directly to the surface of a substrate.

[0078] B. Application

[0079] The coating composition may be applied to a surface of a substrate using spray coating, roller coating, screen printing, or dip coating. The coating composition may be applied such that the coating composition has a cured film thickness from 10 pm, 15 pm, 20 pm, or 22 pm to 25 pm, 28 pm, 30 pm, or 40 pm, or any range using any two of the foregoing values as endpoints, such as from 10 pm to 40 pm, 15 pm to 30 pm, 20 pm to 28 pm, or 22 pm to 25 pm.

[0080] i. Spray Coating

[0081] The interior and exterior coating compositions of the present disclosure can be applied to a substrate using spray coating. Spray coating involves loading the coating composition into device wherein the coating composition is then forced through a nozzle such that the composition is made into a fine aerosol spray. The spray is then directed over a substrate for an even coating.

[0082] ii. Roller Coating

[0083] Roller coating is the process of printing a composition onto a substrate using roll-to-roll technique. The roll-to-roll technique typically uses a single or multiple rollers, which wind the substrate over and through the roller / s covered in the printed composition. The composition is applied to the substrate as the substrate moves along the roller / s.

[0084] iii. Screen Printing

[0085] Screen printing is a stencil-based printing process in which a coating composition is deposited onto a substrate through a mesh screen that defines the desired pattern. The open areas of the mesh allow the material to pass through, while blocked areas prevent deposition. A controlled amount of the coating composition is placed on top of the screen. A squeegee may be used to press and drag the coating composition across the screen, forcing it through the open mesh areas and onto the substrate underneath.

[0086] iv. Dip Coating

[0087] Dip coating is a method for applying uniform coatings to substrates / articles by immersing the substrate in a liquid coating composition and then withdrawing the substrate at a controlled speed. It is especially useful for coating complex shapes or multiple surfaces simultaneously. The substrate may be slowly dipped into a tank or bath comprising the coating composition. The substrate may be held in the bath / tank for a predetermined amount of time to allow proper wetting and adhesion of the coating composition to the surface of the substrate. The substrate may then be withdrawn from the bath at a controlled speed, which determines the thickness of the resulting coating on the surface of the substrate.

[0088] C. Curing

[0089] The coating compositions, once applied to a substrate, may be initially cured at a temperature of 80°C, 100°C, or 120°C to 140°C, 160°C, or 200°C, or any range using any two of the foregoing values as endpoints, such as 80°C to 200°C, 100°C to 160°C, or 120°C to 140°C, for a period of time of 1 min, 2 min, or 4 min to 6 min, 8 min, or 10 min, or any range using any two of the foregoing values as endpoints, such as 1 min to 10 min, 2 min to 8 min, or 4 min to 6 min.

[0090] After the initial cure, the coating composition may be further cured at an increased temperature from 205°C. 225°C, or 250°C to 275°C. 280°C. or 350°C, or any range using any two of the foregoing values as endpoints, such as 205°C to 350°C, 225°C to 280°C, or 250°C to 275°C, for a period of time of 1 min, 5 min, or 10 min to 15 min, 20 min, or 30 min, or any range using any two of the foregoing values as endpoints, such as 1 min to 30 min, 5 min to 20 min, or 10 min to 15 min.

[0091] V. Coating Performance

[0092] The cured coating composition may exhibit the same or improved non-stick properties as traditional fluoropolymer coating compositions. Example 2 includes descriptions of the tests used to evaluate the inventive and comparative cured coatings. Based on the results, the inventive coating compositions of the present disclosure exhibited good initial non-stick properties (milk test) while maintaining good thermal resistance without the use of fluoropolymers.EXAMPLES

[0093] Aspects of the present disclosure are further illustrated by reference to the following examples. It will be apparent to those skilled in the art that many modifications, both to materials, and methods, may be practiced without departing from the scope of the disclosure.EXAMPLE 1: RESIN FORMULATION

[0094] The synthesis of silicone resins were formulated according to Table 1 below and the following synthesis steps.

[0095] Synthesis of Inventive Resins 1-9: Base Catalysis

[0096] To a 250 mL 4-neck flask, attached with an overhead stirrer, a condenser, a N2 inlet and a thermocouple charged 100.0g phenyltrimethoxysilane, 14.0g phenylmethyldimethoxysilane, 20.0g methyltrimethoxysilane, 4.0g diphenyldiethoxysilane and 10g ethanol. The contents were mixed at room temperature and then 1. 15g ammonium hydroxide (30%) was added. 20.1g of distilled water was charged over a period of 30 minutes.

[0097] The temperature of the reaction mixture was raised to 50°C and held for 1 hour.

[0098] The temperature of the reaction mixture was then increased to 70°C and held for 4 hours while mixing the contents. To the reaction mixture, 45g of xylene was added. The lights from the filtrate were distilled at a temperature from 80°C to 120°C. The resin was isolated as a 65 to 85 wt. % solution in xylene.Table 1: Silicone Resin 1-9 FormulationVinylT: Ch2=CH-SiO3 / 2Q: S1O4 / 2EXAMPLE 2: COATING FORMULATION

[0099] The examples in Tables 2 A, 2B, and 2C were prepared by the following general procedure. The silicone resin coating emulsions were formulated by adding the resin solution, any additional co-solvent, and the surfactant, or combination of surfactants, under stirring at 1000 RPM with a saw-tooth blade (3-6 cm diameter). If the resin was solid, it was dissolved first in solvent before adding the surfactant. Stirring continued for 30 minutes at 800-1200 RPM. After 30 minutes, stirring adjusted to 800 - 2000 RPM to provide a tip velocity of 4-12 m / s and water was added in 10 % by weight portions divided equally over 10 min. Each portion wasadded as rapidly in a single shot. Once all the water was added, the emulsion was stirred for an additional 5 - 20 minutes and checked for water dilutability.

[0100] One gram of silicone resin coating emulsion was added to a 20 mL jar and then 6 g of deionized water was added. The dilution was shaken to ensure incorporation. The formulation passes if the product is a free flowing white dispersion throughout the dilution. The formulation fails if the white emulsion does not incorporate into the water, but sits as a separate phase.

[0101] The formulations were allowed to rest overnight and then completed with the addition of silicone oil or silicone gum. Addition was performed under stirring at 1000 RPM using the blade described above. The completed paint was further stirred for 20 min then applied by spray or drawdown methods on 3003 series aluminum (Q412) available from Q-Lab. Before application the panels were abraded with 100 mesh aluminum oxide. The coatings were placed in a 120 °C oven for 1 - 10 minutes, and then transferred to a 300°C oven for 20 minutes. The coatings were cooled to room temperature and the film thickness was 15 - 30 pm.Table 2A: Inventive (Inv) Coating Composition Formulations 1-6'Silicone resin available from Quark Nano Material as a 40% solution containing a mole fraction of 43 of residues of type III where R is Ph, mole fraction of 57 of residues of type I where R is Me, mole fraction of 0 for residues of type II and IV of the total residues2Silicone resin available from Dow as a 100% solids material containing a sum of mole fraction of residues of type III and type II where R is Ph of 45, a sum of mole fraction of residues of type I and II where R is Me of 55, where the total of residues of type II are a mol fraction of 5 of the total residues and where the residues of type IV are a mole fraction of 0 of the total residues3Silicone resin available from Dow as a 100% solids material containing a sum of mole fractions of residues of type III and type II where R is Ph of 57, a sum of mole fractions of residues of type I and II where R is Me of 43, where the mole fraction of residues of type II are 13 -17 of the total residues and where the residues of type IV are a mole fraction of 0 of the total residues7Poloxomer surfactant available from BASF with an HLB of 88Poloxomaer surfactant available from BASF with an HLB of 27’Silicone fluid blend of 50 - 120 cSt at 25oC ± 0.2°C (2000 - 4200 amu) as determined according to ASTM D4283-98(2015) available from Dow as a 100% solids material10Silicone fluid of 300-400 cSt at 25oC ± 0.2°C (10,000 - 15,000 amu) as determined according to ASTM D4283-98(2015) available from Dow as a 100% solids materialnSilicone gum of approximately 500,000 amu available as a waterborne emulsion from Silok IndustriesTable 2A: Inventive (Inv) Coating Composition Formulations 7-11"Poloxomer surfactant available from BASF with an HLB of 8sPoloxomaer surfactant available from BASF with an HLB of 27’Silicone fluid blend of 50 - 120 cSt at 25C(2000 - 4200 amu) as determined according to ASTM D4283-98(2015) available from Dow as a 100% solids material10Silicone fluid of 300-400 cSt at 25°C (10,000 - 15,000 amu) as determined according to ASTM D4283-98(2015) available from Dow as a 100% solids materialnSilicone gum of approximately 500,000 amu available as a waterborne emulsion from Silok Industries12Sorbitan surfactant available from Croda as Tween-8013Silicone resin comprising 60% mol fraction of Type 1 where R is Me, 30% mol fraction of Type II where R is Me and 10% mol fraction Type III where R is Ph as a 72% solids solution in xylene14Silicone resin comprising 60% mol fraction of Type 1 where R is Me, 20% mol fraction of Type II where R is Me 10% mol fraction Type III where R is Ph, 10% mol fraction Type III where R is vinyl as a 72 % solids solution in xylene15Silicone resin comprising 60% mol fraction of Type 1 where R is Me, 20% mol fraction of Type 11 where R is Me and 20% mol fraction Type III where R is vinyl as a 72% solids solution in xylene16Silicone resin comprising 60% mol fraction of Type 1 where R is Me, 20% mol fraction of Type II where R is Me and 20% mol fraction Type IV as a 63% solids solution in xyleneTable 2C: Comparative (Comp) Coating Composition Formulations4Silicone resin available from Dow as a 100% solids material containing 100% Ph corresponding to (III) and 0% D monomers corresponding to (II) and having no monomers corresponding to (I) and (IV) of tire polysiloxane resin5Silicone resin available from Dow as a 100% solids material containing a sum of mole fraction of residues of type III and type II where R is Ph of 66, a sum of mole fraction of residues of type I and II where R is Me of 44, where the total of residues of type II are a mol fraction of 18-22 of the total residues and where the residues of type IV are a mole fraction of 0 of the total residues6Silicone resin available from Dow as an 80% solution containing a sum of mole fraction of residues of type III and type II where R is Ph of 55, a sum of mole fraction of residues of type I and II where R is Me of 45, where the total of residues of type II are a mol fraction of 35-45 of the total residues and where the residues of type IV are a mole fraction of 0 of the total residues7Poloxamer surfactant available from BASF with an HLB of 8sPoloxamer surfactant available from BASF with an HLB of 27’Silicone fluid blend of 50 - 120 cSt at 25oC ± 0.2°C (2000 - 4200 amu) as determined according to ASTM D4283-98(2015) available from Dow as a 100% solids material10Silicone fluid of 300-400 cSt at 25oC ± 0.2°C (10,000 - 15,000 amu) as determined according to ASTM D4283-98(2015) available from Dow as a 100% solids material“Silicone gum of approximately 500,000 amu available as a waterborne emulsion from Silok IndustriesEXAMPLE 3: COATING PERFORMANCE

[0102] Initial nonstick test

[0103] The milk nonstick test was performed after the cure cycle. The results are shown in Table 3. In general, there was no differentiation between inventive and comparative examples.

[0104] Thermal cycle nonstick test

[0105] After the initial nonstick test, the coatings were wiped clean and placed in a 250 °C oven for 1 hour. After this time, the coatings were removed and plunged in water that is room temperature. The coatings were dried and the milk nonstick test was performed. If the coating scored a 2 or higher, it was resubmitted to the test. If the coating scored below a 2, testing was halted. Performance was judged by the number of cycles that the coating maintained a milk nonstick score of 2 or higher. The inventive examples with phenyl and D units within the inventive ranges are coatings from waterborne formulations with longer lasting nonstick than the comparative examples.

[0106] Milk nonstick test

[0107] The cured coating was placed in an oven at 120 °C and approximately 0.4 g whole milk was added to the coating surface. This was repeated to give 2 - 4 total spots of milk on the surface. The coating with milk was heated in the oven for 5 minutes then transferred to an oven at 200 °C. The coating with milk was heated in the second oven for 10 minutes. After this time the coating was removed and placed under a stream of cold water for 20 seconds. The coating was held at an angle such that the stream of water and the coating created an angle of 90 - 120 °. The coating was moved so that each milk spot was affected. If the stream of water removed the milk completely the coating was given a 5 rating. If the stream of water did not remove the milk but a gentle downward sliding pressure from a thumb removed it, the coating was given a 4 rating. If a vigorous downward sliding pressure was required, the coating was given a 3 rating. If a vigorous downward sliding pressure only removed half of the milk spot, the coating was given a 2 rating. If a vigorous downward sliding pressure removed less than half of the milk the coating was given a 1 rating. The final score was an average over all milk spots.Table 3: Coating Performance Results

[0108] The coating compositions of the present disclosure shows that a waterborne composition with longer lasting nonstick can be achieved through the careful selection of resinstructure, silicone fluid or gum, and surfactant. The inventive examples, which are waterborne with phenyl and D units within the inventive ranges, exhibit longer lasting nonstick in the thermal nonstick test (5 - 7 cycles) than the comparative examples (2- 4 cycles). This was true for silicone fluid and silicone gum nonstick additives.

[0109] In contrast with solvent borne examples, phenyl substituents and D monomers out side of the inventive ranges inhibit long term nonstick performance in the present waterborne system. Without wishing to be bound by theory, this is potentially due to a compatibility interaction of the resin D monomers and the resin phenyl groups with the silicone nonstick additives. Possibly, increased D monomers are likely to hold the additive in the bulk preventing nonstick at the surface. Conversely, there is a possibility of incompatibility of the release agent with the phenyl functionality of the resin leading to premature loss of nonstick.

[0110] Wherein particular examples of this disclosure have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present disclosure may be made without departing from the disclosure as defined in the appended claims. This application is therefore intended to cover any variations, uses, or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this disclosure pertains and which fall within the limits of the appended claims.ASPECTS

[0111] Aspect 1 is a waterborne, curable coating composition, comprising: a polysiloxane resin formed from the following siloxane monomer residues:(I) [R1Si(O)3 / 2]a, wherein: a is the molar fraction of (I) and is from 30-60, based on the total moles of polysiloxane resin; and R1is a C1-C30 linear or C3-C30 cyclic alkyl group;(II) optionally [R2R3Si(O)]b, wherein: b is the molar fraction of (II) and is from 0-30, based on the total moles of polysiloxane resin; and R2and R3are each independently a C1-C30 linear or C3-C30 cyclic alkyl group, or a Ce or C7 aryl group;(TIT) [R4Si(O)? / 2]c , wherein: c is the molar fraction of (TI) and is from 0-70, based on the total moles of polysiloxane resin; and R4is at least one of an aryl group, a vinyl group, or a combination thereof;(TV) optionally [Si(O)4 / 2]d, wherein d is the molar fraction of (TV) and is from 0-20, based on the total moles of polysiloxane resin;wherein the resin comprises 20 mol% or less of monomers (IT), based on total moles of monomers (I), (IT), (ITT), and (TV) in the polysiloxane resin; wherein the resin comprises less than 90 mol% aryl groups R4, based on total moles of groups R1, R2, R3, and R4;a polydimethylsiloxane; a surfactant; and water, wherein the coating composition comprises particles of the polysiloxane resin emulsified by the surfactant and dispersed within the water.

[0112] Aspect 2 is the coating composition of Aspect 1, wherein the composition comprises at least 10 wt. % water, based on a total weight of the composition.

[0113] Aspect 3 is the coating composition of Aspect 1, wherein the composition comprises less than 50 wt. % of any non-aqueous organic solvent, based on a total weight of the composition.

[0114] Aspect 4 is coating composition of any one of Aspects 1-3, wherein the surfactant comprises: a surfactant of Formula Ta:wherein x is the number of repeat units of an ethylene glycol monomer from 120-150, y is the number of repeat units of a propylene glycol monomer from 40-60, and z is the number of repeat units of an ethylene glycol monomer from 120-150; and / ora surfactant of Formula lb:wherein x is the number of repeat units of a propylene glycol monomer from 40-60, y is the number of repeat units of an ethylene glycol monomer from 120-150, and z is the number of repeat units of a propylene glycol monomer from 40-60; and / ora surfactant of Formula II:wherein w is the number of repeat units from 1-17, x is the number of repeat units from 1-17, y is the number of repeat units from 1-17, and z is the number of repeat units from 1-17, and w+x+y+z=20.

[0115] Aspect 5 is the coating composition of any one of Aspects 1-4, wherein the surfactant comprises from 0.1 wt. % to 10 wt. % based on a total weight of the coating composition.

[0116] Aspect 6 is the coating composition of any one of Aspects 1-5, wherein the resin comprises 10 mol% or less of monomers (II), based on total moles of monomers (I) , (II), (III), and (IV) in the resin.

[0117] Aspect 7 is the coating composition of any one of Aspects 1-6, wherein the resin comprises 5 mol % or less of monomers (II), based on total moles of monomers (I), (II), (III), and (IV) in the resin.

[0118] Aspect 8 is the coating composition of any one of Aspects 1-7, wherein the resin comprises less than 60 mol % of siloxane monomer residue (III), based on total moles of groups R1, R2, R3, and R4.

[0119] Aspect 9 is the coating composition of any one of Aspects 1-8, wherein the poly siloxane comprises from 10 wt.% to 90 wt.% based on a total weight of the coating composition.

[0120] Aspect 10 is the coating composition of any one of Aspects 1-9, wherein the polydimethylsiloxane comprises a silicone fluid comprising: a viscosity from 25 cSt to 15,000 cSt, as determined according to ASTM D4283-98 (2015); and / or an atomic mass from 1,000 to 80,000 AMU, as determined by gel permeation chromatography-GPC calibrated using polystyrene beads.

[0121] Aspect 11 is the coating composition of any one of Aspects 1-10, wherein the polydimethylsiloxane comprises a silicone gum comprising: a viscosity from 1,000,000 cSt to 20,000,000 cSt, as determined according to ASTM D2983 (2023): and / or an atomic mass from 100,000 to 20,000,000 AMU, as determined by gel permeation chromatography-GPC calibrated using polystyrene beads.

[0122] Aspect 12 is the coating composition of any one of Aspects 1-11, wherein the polydimethylsiloxane resin comprises from 1 wt.% to 20 wt.%, based on a total weight of the coating composition.

[0123] Aspect 13 is a method of coating an article of cookware or bakeware, comprising: applying, to a surface of the article, the coating composition of any of Aspects 1-12; and curing the coating.

[0124] Aspect 14 is the method of Aspect 13, wherein the applying step comprises spray coating and / or roller coating.

[0125] Aspect 15 is an article of cookware or bakeware, comprising a surface coated with a coating derived from the coating composition of any of Aspects 1-14.

Claims

CLAIMSWhat is claimed is:

1. A waterborne, curable coating composition, comprising:a polysiloxane resin formed from the following siloxane monomer residues:(I) [R1Si(O)3 / 2]a, wherein:a is the molar fraction of (I) and is from 30-60, based on the total moles of poly siloxane resin; andR1is a C1-C30 linear or C3-C30 cyclic alkyl group;(II) optionally [R2R3Si(O)]b, whereinb is the molar fraction of (II) and is from 0-30, based on the total moles of polysiloxane resin; andR2and R3are each independently a C1-C30 linear or C3-C30 cyclic alkyl group, or a C , or C7 aryl group;(III) [R4Si(O)3 / 2]c , wherein:c is the molar fraction of (III) and is from 0-70, based on the total moles of polysiloxane resin; andR4is at least one of an aryl group, a vinyl group, or a combination thereof;(IV) optionally [Si(O)4 / 2]d, whereind is the molar fraction of (IV) and is from 0-20, based on the total moles of polysiloxane resin;wherein the resin comprises 20 mol% or less of monomer residue (II), based on total moles of monomer residues (I), (II), (III), and (IV) in the polysiloxane resin;wherein the resin comprises less than 90 mol% aryl groups R4, based on total moles of groups R1, R2, R3, and R4;a polydimethylsiloxane;a surfactant; andwater, wherein the coating composition comprises particles of the polysiloxane resin emulsified by the surfactant and dispersed within the water.

2. The coating composition of claim 1 , wherein the composition comprises at least 10 wt. % water, based on a total weight of the composition.

3. The coating composition of claim 1, wherein the composition comprises less than 50 wt. % of any non-aqueous organic solvent, based on a total weight of the composition.

4. The coating composition of any one of claims 1-3, wherein the surfactant comprises:a surfactant of Formula la:wherein x is the number of repeat units of an ethylene glycol monomer from 120- 150, y is the number of repeat units of a propylene glycol monomer from 40-60, and z is the number of repeat units of an ethylene glycol monomer from 120-150; and / ora surfactant of Formula lb:wherein x is the number of repeat units of a propylene glycol monomer from 40- 60, y is the number of repeat units of an ethylene glycol monomer from 120-150, and z is the number of repeat units of a propylene glycol monomer from 40-60; and / ora surfactant of Formula II:wherein w is the number of repeat units from 1-17, x is the number of repeat units from 1-17, y is the number of repeat units from 1-17, and z is the number of repeat units from 1-17, and w+x+y+z-20.

5. The coating composition of any one of claims 1-4, wherein the surfactant comprises from 0.1 wt. % to 10 wt. % based on a total weight of the coating composition.

6. The coating composition of any one of claims 1-5, wherein the resin comprises 10 mol% or less of monomer residue (II), based on total moles of monomer residues (I) , (II), (III), and (IV) in the resin.

7. The coating composition of any one of claims 1-6, wherein the resin comprises 5 mol % or less of monomer residue (II), based on total moles of monomer residues (I), (II), (III), and (IV) in the resin.

8. The coating composition of any one of claims 1-7, wherein the resin comprises less than 60 mol % of siloxane monomer residue (III), based on total moles of monomer residues (I), (II), (III), and (IV) in the resin.

9. The coating composition of any one of claims 1-8, wherein the polysiloxane comprises from 10 wt.% to 90 wt.% based on a total weight of the coating composition.

10. The coating composition of any one of claims 1-9, wherein the polydimethylsiloxane comprises a silicone fluid comprising:a viscosity from 25 cSt to 15,000 cSt, as determined according to ASTM D4283-98 (2015); and / oran atomic mass from 1,000 to 80,000 AMU, as determined by gel permeation chromatography-GPC calibrated using polystyrene beads.

11. The coating composition of any one of claims 1-10, wherein the poly dimethylsiloxane comprises a silicone gum comprising:a viscosity from 1,000,000 cSt to 20,000,000 cSt, as determined according to ASTM D2983 (2023); and / oran atomic mass from 100,000 to 20,000,000 AMU, as determined by gel permeation chromatography-GPC calibrated using polystyrene beads.

12. The coating composition of any one of claims 1-11, wherein the polydimethylsiloxane resin comprises from 1 wt.% to 20 wt.%, based on a total weight of the coating composition.

13. A method of coating an article of cookware or bakeware, comprising:applying, to a surface of the article, the coating composition of any of claims 1-12; and curing the coating.

14. The method of claim 13, wherein the applying step comprises spray coating and / or roller coating.

15. An article of cookware or bakeware, comprising a surface coated with a coating derived from the coating composition of any of claims 1-14.

Images