Flexible ballistic fabric and articles made therefrom
View Patent ↗The invention concerns a penetration resistant article comprising a plurality of substantially planar elements; each element comprising at least one fibrous layer formed of multifilaments having a linear density of at least 200 dtex, a tenacity of at least 10 grams per dtex, and an elongation to break of at least 2%; and superposed upon at least one of the fibrous layers, a polymer layer comprising a thermoplastic polymer, a thermoset polymer, or a polymer having glass transition temperature of −40° C. to 0° C., a molecular weight (Mw) of 20,000 to 100,000, and a viscosity of about 2×10 6 to about 10 13 poise at 20° C.; the polymer layer covering and being adhered to from 25% to 75% of the area of the fibrous layer, wherein the area not covered by the polymer layer comprises a plurality of discrete areas.
1. A method of making an article for use in resisting ballistic threats, comprising:
providing a polymer layer comprising a thermoplastic polymer, a thermoset polymer or a polymer having a glass transition temperature of −40° C. to 0° C., a molecular weight of 20,000 to 100,000, and a viscosity of about 2×10 6 to about 10 13 poise at 20° C.;
forming a plurality of holes in said polymer layer; and
covering and adhering said polymer layer to a first side of a fibrous layer, said fibrous layer having a first and a second side and comprising a plurality of multifilament yarns having a linear density of at least 200 dtex, a tenacity of at least 10 grams per dtex, and an elongation to break of at least 2%;
whereby more than 25% and less than 75% of the first side of the fibrous layer is covered and adhered by the polymer layer.
2. The method of claim 1 , wherein the polymer layer comprises a thermoplastic or thermoset polymer.
3. The method of claim 1 , wherein the holes are discrete and each of the holes has an area from 0.25 cm 2 to 150 cm 2 .
4. The method of claim 1 , wherein the discrete areas are circular, square, triangular, rectangular, polygonal or defined by irregular contours.