Abstract A method for coating a flexible reticulate open structure with a normally viscous liquid curable isocyanate derived polymer so as not to block the openings in the structure is described. In particular a small amount of a polysiloxane oil of the general formula IS EMPLOYED WITH THE LIQUID ISOCYANATE DERIVED POLYMER SO AS TO MODIFY THE SURFACE TENSION OF THE LIQUID FOR PROVIDING A THIN COATING ON THE SURFACES OF THE STRUCTURE. Novel products are prepared from a coating of diphenyl methane diisocyanate and a polyol having a hydroxyl number between about 100 and 1,000. The products are particularly useful for filtering purposes where the loading by the material to be filtered would deform a flexible structure, such as can happen with flexible polyurethane or fiber glass reticulate structures used by the prior art.
THE METHOD FOR FORMING A RIDIG STRUCTURE WHICH COMPRISING: A. COATING A CORE OF A RETICULATE FLEXIBLE THREE DIMENSIONAL SKELETAL STRUCTURE HAVING OPENINGS BETWEEN STRANDS WHICH FROM THE STRUCTURE WITH A LIQUID NON-FOAM POLYISOCYANATE DERIVED POLYMER FORMED BY MIXING A POLYISOCYANATE AND A POLYOL HAVING A HYDROXYL BETWEEN 100 AND 1,000 IMMEDIATELY PRIOR TO COATING AND WHICH CURES TO A THIN COATING AND CONTAINING IN ADMIXTURE THEREWITH BETWEEN ABOUT 0.1 AND 10 PARTS BY WEIGHT OF POLYSILOXANE OIL PER 100 PARTS BY WEIGHT OF THE POLYOL SO AS TO THINLY COAT THE STRANDS WITH POLYURETHAN POLYMER WITHOUT BLOCKING THE OPENINGS BETWEEN THE STRANDS AND
Claim 2
Independent Claim
104 words
THE METHOD FOR FORMING A RIDIG STRUCTURE WHICH COMPRISING: A. COATING A CORE OF A RETICULATE FLEXIBLE THREE DIMENSIONAL SKELETAL STRUCTURE HAVING OPENINGS BETWEEN STRANDS WHICH FROM THE STRUCTURE WITH A LIQUID NON-FOAM POLYISOCYANATE DERIVED POLYMER FORMED BY MIXING A POLYISOCYANATE AND A POLYOL HAVING A HYDROXYL BETWEEN 100 AND 1,000 IMMEDIATELY PRIOR TO COATING AND WHICH CURES TO A THIN COATING AND CONTAINING IN ADMIXTURE THEREWITH BETWEEN ABOUT 0.1 AND 10 PARTS BY WEIGHT OF POLYSILOXANE OIL PER 100 PARTS BY WEIGHT OF THE POLYOL SO AS TO THINLY COAT THE STRANDS WITH POLYURETHAN POLYMER WITHOUT BLOCKING THE OPENINGS BETWEEN THE STRANDS AND
Claim 3
Dependent Claim
36 words
The method of claim 1 wherein the coating is applied by compressing the skeletal structure with the liquid polyurethane polymer deposited on an exposed outer surface thereof between at least one roller and an opposing surface.
Claim 4
Dependent Claim
34 words
The method of claim 2 wherein the spacing between the roller and a spaced apart slide plate as the opposing surface is adjusted to compress the foam to about 10% of its original thickness.
Claim 5
Dependent Claim
26 words
The method of claim 1 wherein the core is a reticulated polyurethane foam of interconnected strands having between about 10 and 100 openings per linear inch.
Claim 6
Dependent Claim
16 words
The method of claim 1 wherein the coated strands are compressed to permanently interbond the strands.
Claim 7
Dependent Claim
18 words
The method of claim 1 wherein the polyisocyanate is diphenylmethane disocyanate and the polyol is a polyether polyol.