Graphics-bearing element and fluid line marking tape

DETAILED DESCRIPTION What is claimed is: 1.
A graphics-bearing marking element comprising an ink graphics layer comprising a polyvinyl formal resin present in an amount by weight in the range of 21% to 71% and having an exposed portion and providing marking indicia.
2.
The element of claim 1 in which said resin is present in an amount by weight in the range of 25 percent to 50 percent.
3.
The element of claim 1 which includes halogen-free pigment.
4.
The element of claim 3 which includes a layer of heat-activatable adhesive comprising polyester resin with a blocked polyisocyanate.
5.
The element of claim 1 which includes a transparent plastic layer.
6.
The element of claim 1 which includes a primer layer between said graphics layer and said plastic layer.
7.
The element of claim 4 or 5 which is a fluid line marking tape.
8.
The element of claim 6 which is a fluid line marking tape.
9.
The element of claim 6 wherein said primer comprises polyester resin with polyisocyanate.
10.
The element of claim 5 wherein said transparent plastic layer comprises polyester.




Description:
FIELD OF THE INVENTION This invention relates to graphics bearing elements highly resistant to liquids, and in particular to a heat-activated fluid line marking tape useful in aircraft environments.
BACKGROUND OF THE INVENTION The prior art has had difficulty providing marking labels suitably resistant to environments of hydraulic fluid, oils, aircraft fuels and other liquids.
SUMMARY OF THE INVENTION We have found that products of highly desirable durability in such environments may be provided through using in the ink of a graphic layer a polyvinyl formal resin.
In preferred embodiments, the polyvinyl formal resin is present in amount in the range of 25-50%, is tied to a transparent polyester layer through a primer layer, and carries on the side of the laminate away from the polyester layer a heat-activatable adhesive layer.
PREFERRED EMBODIMENT We turn now to a presently preferred embodiment of the invention