Removal of protective paper tape and maskants
AssigneeBoeing Aerospace Company
InventorWalter Batiuk
Life of this patent
Estimating the term…
Abstract
Protective paper adhesively bonded to stainless steel surfaces is removed by applying an aqueous solvent mixture containing a ketone or similar solvent, alcohol, toluene, and a wetting agent, all of which are maintained in a single phase. The relative composition of the solvent components is maintained on the area of solvent application by covering with a suitable airtight cover. The single-phase solvent mixture penetrates the paper and adhesive, and the vapor pressure of the solvent mixture causes the paper and adhesive to blister and loosen. The paper is peeled off after sufficient time elapses. Any remaining adhesive can be removed with a second solvent containing a ketone and toluene.
Claims5
A method for the removal of adhesively-bound protective paper from a substrate, comprising:
- applying a single-phase solvent solution that penetrates the paper and adhesive consisting essentially of by volume:
- ______________________________________ a ketone from the group of methyl ethyl ketone, acetone, butyl acetone 50-70% a lower aliphatic alcohol 10-20% toluene 5-10% a non-ionic wetting agent from the group of propylene glycol, NH.sub.4 OH or a sulfate- free detergent 1-10% deionized water 5-10% ______________________________________
- immediately covering the treated area of with a vaportight barrier sheet sealed about its periphery to prevent selective evaporation of components of said solvent solution thereby maintaining said solvent solution in a single phase until the organic coating or maskant loosens and blisters from the solvent action and vapor pressure of the single-phase solution,
- removing said barrier, and
- mechanically removing said adhesively-bound protective paper from the substrate.
A method for the removal of adhesively-bound protective paper from polished stainless steel which has no corrosive effect on the stainless steel, comprising the steps of:
- manually peeling away any loose paper or,
- making a liberal application of a solution on a volume basis, the solution consisting essentially of:
- ______________________________________ a ketone 50-70% lower aliphatic alcohol 10-20% toluene 5-10% deionized wetting agent 1-10% deionized water 5-10% ______________________________________ (All figures above given in volume percentages.)
- quickly covering the treated area with a vaportight barrier sheet and sealing the edges thereof to prevent selective evaporation of constituents of said solution and to maintain said solution in a single phase,
- maintaining said sheet in vaportight relation to said surface until said solution penetrates said protective paper and adhesive to blister and loosen said protective paper,
- removing said sheet,
- rapidly scraping the blistered and loose protective paper until all protective paper is removed, and
- drying the treated area thoroughly.
Dependencies are inferred from the claim text.