Woven fabric made with a yarn having periodic flat spots

A woven fabric of glass fiber warp yarn and glass fiber fill yarn, where the glass fiber fill yarn comprises a strand of individual glass filaments, the strand having a primary cross-sectional shape and periodic flat spots with a flat cross-sectional shape which is more elongated than the primary cross-sectional shape, where the effect of the flat spots is differentiated glass fiber fill yarn in the woven fabric, where the differentiated glass fiber fill yarn is wider than the remainder of the glass fiber fill yarn and has an average length within the range of from about 0.5 to about 10 cm, and where the differentiated glass fiber fill yarn has an average width within the range of from about 125 to about 300 percent of the average width of the remainder of the glass fiber fill yarn.

A woven fabric of glass fiber warp yarn and glass fiber fill yarn, where the glass fiber warp yarn comprises a strand of individual glass filaments, the strand having a primary cross-sectional shape and periodic flat spots with a flat cross-sectional shape which is more elongated than the primary cross-sectional shape, where the effect of the flat spots is differentiated glass fiber warp yarn in the woven fabric.