Patent ID: 7862669

Claim:
The method of forming a lightweight, high performance, glass fiber product blanket for acoustical and thermal insulation, that includes: a) treating glass fibers with a fluid binding agent at elevated temperature in an oven to form a first cohesive glass fiber layer of thickness t 1 traveling endwise, and winding that layer into a roll above a travel zone of that layer, b) repeating said treating to form a second cohesive glass fiber layer of thickness t 2 traveling endwise over said zone below said roll and into an oven on a conveyor, and unrolling said first layer from its said roll to travel into the oven in overlying surface to surface contacting relation to the traveling second layer, c) subjecting said overlying layers to simultaneous heat treatment and pressurization in the oven to compress the first and second layers to a controlled density thickness t 3 which is substantially less than t 1 and t 2 , and to progressively bond said first and second layers together in laminated relation to form the product blanket, d) and removing said laminated product from the oven, e) and wherein the glass fibers in each layer have cross dimensions between 2.0 and 9.90 HT, where HT=0.00001 inch, the bulk of the fibers having lengths between 1 and 2 microns.