Cleaning compositions for solid surfaces – auxiliary compositions – Cleaning compositions or processes of preparing – For cleaning a specific substrate or removing a specific...
Patent
1998-08-19
2000-08-15
Gupta, Yogendra
Cleaning compositions for solid surfaces, auxiliary compositions
Cleaning compositions or processes of preparing
For cleaning a specific substrate or removing a specific...
510201, 510407, 510434, 510476, 510493, 510499, 510505, 510506, C11D 726, C11D 732, C11D 750
Patent
active
06103682&
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a thickened composition intended for stripping paints and/or varnishes.
The applications for patents EP 490 726 and EP 573 339 describe stripping compositions comprising an aprotic polar solvent and a non-protic ether. The polar solvent can be dimethyl sulphoxide (DMSO) or N-methylpyrrolidinone (NMP). The ether must be non-protic, i.e. must be devoid of a covalent bond X--H in which X is a heteroatom, and must also have the smallest possible molecular volume. This ether can, for example, be 2-methoxy-1,3-dioxolane. The composition can comprise a thickener such as methylcellulose or an Aerosil (pyrogenic silica).
Moreover, the application for patent GB 2,150,587 describes a composition for stripping paints which comprises methylene chloride, methanol and a copolymer comprising vinyl chloride in the majority and an acrylic ester in the minority, containing free hydroxyl groups. This composition must also include a thickener in order to obtain proper viscosity and good adhesion. This thickener is advantageously a polymer of acrylic acid in combination with a saccharide of the type sold by the company B.F. GOODRICH under the trademark Carbopol.RTM. and, in particular, the Carbopols.RTM. 940, 941 and 934 and their technical equivalents in the 800 series.
The thickeners of this type are employed together with a neutralizing amine, generally an aliphatic amine having 6 to 20 carbon atoms. The amine is advantageously liquid at ambient temperature. Among these amines particular emphasis is given to C8 to C14 N,N-dimethylated amines, such as N,N-dimethyltetradecylamine.
This composition, which is based on methylene chloride (solvent), also contains from 0.05 to 0.1% of a wax in order to counter the evaporation of the solvent, and a small quantity of water which is required for the formation of hydrogen bonds with the thickener of the Carbopol.RTM. type, the latter being present in a quantity by weight of from 0.3 to 1%, for example from 0.5 to 0.6% by weight relative to the weight of the composition.
The application for patent WO 92/05224 describes a composition for stripping paints, varnishes and the like which does not have a chlorinated solvent and which possesses an effective rheology identical to that of a paint.
Although the composition can be devoid of acetic acid and water, the most preferred composition nevertheless comprises the following liquid ingredients, listed as a volume percentage of the final composition:
______________________________________ Dibasic ester of aliphatic acid
48%
N-methyl-2-pyrrolidinone
15%
Mixture of propylene glycol methyl ether
20%
and dipropylene glycol methyl ether
Acrylic polymer 5%
Water 5%
Acetic acid 2%
______________________________________
The preferred dibasic ester is commercially available under the name D.B.E. (DuPont Chemicals Inc.).
The function of the acrylic polymer is to enhance the rheology of the composition. These liquids are preferably mixed with a thickener in order to form a gel. The thickener is preferably hydroxypropyl methylcellulose, employed in a content of approximately 1%. Other fillers may be added to this gel, such as polymers, titanium dioxide and colorants.
This latter composition of the prior art comprises glycol ethers, which are protic owing to the presence of free OH groups, and aliphatic diesters in a considerable percentage, 48%. These diesters are insoluble in water, which may give rise to difficulties in rinsing the substrate after it has been stripped of its coats of paint.
The aim of the present invention is to provide a paint-stripping composition in the form of a thickened formulation which is devoid of halogenated products and is more effective in terms of its speed of action on coats of paint than the compositions of the prior art. In addition, this thickened formulation should not separate during the stripping period, even in a moist atmosphere, must be easy to apply by brush or roller and, finally, must be easily rinsable with water.
This aim is achieved by a thi
REFERENCES:
patent: 2694658 (1954-11-01), Crepeau et al.
patent: 5612303 (1997-03-01), Takayanagi et al.
patent: 5753603 (1998-05-01), Lallier et al.
Elf Atochem S.A.
Gupta Yogendra
Ingersoll Christine
LandOfFree
Thick paint stripping composition does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Thick paint stripping composition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Thick paint stripping composition will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2006842