Ballistic resistant thermoplastic sheet, process of making and its applications

A process for forming a dimensionally stable open fabric, the process comprising:

• a) providing a woven fabric comprising high tenacity elongate bodies interwoven with transversely disposed binding elongate bodies, said high tenacity elongate bodies comprising a thermoplastic polymer, having a tenacity of at least about 14 g/denier and having a tensile modulus of at least about 300 g/denier, wherein adjacent high tenacity elongate bodies are spaced apart from each other by a distance equivalent to at least about 10% of the width of the high tenacity elongate bodies;
• and wherein said binding elongate bodies at least partially comprise a thermoplastic polymer having a melting temperature below a melting temperature of the high tenacity elongate bodies;
• b) at least partially melting the thermoplastic polymer of the binding elongate bodies;
• and
• c) allowing the melted thermoplastic polymer of the binding elongate bodies to solidify, whereby the binding elongate bodies are bonded to the high tenacity elongate bodies, thereby forming a dimensionally stable open fabric.

A process for forming a closed, thermally fused multilayer article comprising:

• a) providing an open woven fabric comprising high tenacity elongate bodies interwoven and bonded with transversely disposed binding elongate bodies, said high tenacity elongate bodies comprising a thermoplastic polymer, having a tenacity of at least about 14 g/denier and having a tensile modulus of at least about 300 g/denier, wherein adjacent high tenacity elongate bodies are spaced apart from each other by a distance equivalent to at least about 10% of the width of the high tenacity elongate bodies;
• and wherein said binding elongate bodies at least partially comprise a thermoplastic polymer having a melting temperature below a melting temperature of the high tenacity elongate bodies;
• b) providing (i) a closed, fused sheet wherein said closed, fused sheet comprises high tenacity elongate bodies interwoven and bonded with transversely disposed binding elongate bodies, said high tenacity elongate bodies comprising a thermoplastic polymer, said high tenacity elongate bodies having a tenacity of at least about 14 g/denier and also having a tensile modulus of at least about 300 g/denier, and wherein said binding elongate bodies at least partially comprise a thermoplastic polymer having a melting temperature below a melting temperature of the high tenacity elongate bodies, and wherein the closed, fused sheet has substantially no gaps between adjacent high tenacity elongate bodies and wherein said adjacent high tenacity elongate bodies do not overlap;
• or providing (ii) a web of non-woven, parallel high tenacity elongate bodies having a tenacity of at least about 14 g/denier and a tensile modulus of at least about 300 g/denier;
• c) adjoining the open woven fabric together with either the closed, fused sheet (i) or the web (ii), wherein the high tenacity elongate bodies of the closed, fused sheet or the high tenacity bodies of the web are oriented at a non-parallel angle relative to the high tenacity elongate bodies of the open woven fabric;
• and
• d) thermally pressing the adjoined open woven fabric and the closed, fused sheet (i) or the web (ii) together under conditions sufficient to attach the open woven fabric to either the closed, fused sheet (i) or the web (ii) and to wherein the high tenacity elongate bodies forming the open woven fabric are flattened, thereby causing the longitudinal edges of the adjacent high tenacity elongate bodies in the open woven fabric to contact each other, whereby there are substantially no gaps between said adjacent high tenacity elongate bodies and wherein said adjacent high tenacity elongate bodies do not overlap.