AQUEOUS COATING REMOVER COMPOSITIONS AND CONCENTRATES
Publication Date: 2014-Mar-07
The IP.com Prior Art Database
Aqueous coating remover compositions and concentrates and their methods of use are disclosed. The aqueous compositions comprise 3 to 25 wt.% of a monounsaturated C10-C17 fatty amide, 1 to 8 wt.% of an alkanolamine, 3 to 50 wt.% of a surfactant, and at least 30 wt.% of water. The compositions have a pH within the range of 10 to 12, and the amount of surfactant present equals or exceeds the amount of fatty amide. The coating remover compositions and concentrates loosen, dissolve or disintegrate common paints, adhesives, sealants, elastomers, baked-on soils, and other coatings. Surprisingly, the coating remover compositions can be used at solvent concentrations as low as 5% or less to effectively remove polyurethanes, pressure-sensitive adhesives, rubber cements, cyanoacrylates, acrylics, polyvinyl acetates, epoxies, and cellulose nitrates.
FIELD OF THE INVENTION
The invention relates to aqueous coating remover compositions and concentrates useful for removing paints, coatings, adhesives, sealants, and other hard-to-remove materials.
BACKGROUND OF THE INVENTION
Paints, coatings, adhesives, and sealants come in many types and compositions, but most of them are difficult to remove after they have been applied and allowed to cure. Traditional remover compositions are primarily or exclusively solvent based, and most include aggressive organic solvents, particularly dichloromethane, methyl ethyl ketone, aromatic hydrocarbons, N-methyl-2-pyrrolidone, dimethylformamide, dibasic esters, or the like. Many of these organic solvents are regulated as VOCs and toxic substances.
To a limited degree, fatty amides have been described as components of a coating remover. For instance, EP 2345702 describes a non-aqueous paint or coating remover comprising a dialkylamide and a second solvent. The dialkylamide can be a fatty amide derived from a C6-C22 saturated or unsaturated fatty acid. The second solvent is a traditional organic solvent used for coating removal. Auxilliary agents, including activators and surfactants can be included. The compositions utilize 40-99 wt.% of the dialkylamide component and typically up to 10 wt.% of the surfactant.
WO 2011/086421 describes a floor stripper composition based on renewable raw materials. The stripper comprises a plant- or animal oil-derived C8-C24 fatty dialkylamide, a solubilizer, a nonionic surfactant, and an alkalinity source. The alkalinity source can be an alkanolamine, although all of the tested compositions use potassium hydroxide, which is used to neutralize a fatty acid that is normally present in the formulation. The nonionic surfactant is also used in a minor proportion compared with the amount of dialkylamide present. The naturally derived dialkylamide could have unsaturation, but there is no indication or evidence of any advantage of having unsaturation in the fatty chain of the dialkylamide.
EP 0189225 describes “built” liquid detergents comprising anionic, ethoxylated nonionic, and C8-C20 fatty amide surfactants. The detergents, which also include a carboxylate or fatty acid builder, are used for heavy duty laundry (HDL) applications. Alkanolamines are taught as possible neutralizing agents. The pH of the formulations is in the range of 7.0 to 9.0.
U.S. Pat. No. 7,309,684 teaches oil-in-water emulsified removers comprising an ethoxylated alcohol surfactant. Fatty amides are also taught as possible nonionic surfactant components, but monounsaturated fatty amides are not mentioned. The emulsions, which comprise water, an organic solvent, and a surfactant, are used to remove coatings, w...