Thermal garment design

DETAILED DESCRIPTION What is claimed is: 1.
In combination: a thermal garment insulation means of a fiber layer sandwiched between two layers of fabric; said fiber and fabric layers with two reflective plastic film layers intervening; said plastic film layers having venting holes offset from one another in opposing layers.
2.
The combination of claim 1 wherein the reflective layers are provided with a flat black finish on their outer surfaces.
3.
In combination: a thermal garment insulation means of horizontal fabric box constructions containing loose fibers or down; said box constructions having alternately narrow and wide surfaces on interior and exterior portions; said wide surfaces of box constructions having reflective plastic film layers sewn inside each box construction.
4.
The combination of claim 3 wherein the plastic film layers are provided with a flat black finish on their outer surfaces.




Description:
PRIOR ART STATEMENT This invention relates to fiber- or down-insulated garments, and wearable thermal gear that utilizes reflective heat insulation.
The most efficient thermal garments available at present, in terms of their insulating abilty versus their weight, are those insulated with manmade fibers or down.
These garments block convected heat loss by trapping many small "dead air" spaces among very fine fibers.
This means of insulating is very effective, but garments of this type which are designed for use in the extreme cold are quite bulky, since the need for a better insulating ability is answered by a deeper fiber layer.
One way to reduce bulk is to develop fibers that trap smaller dead air spaces, so that the thickness of the insulating layer may be reduced with no loss of efficiency.
Other researchers are developing such new fibers, and these will no doubt play a big part in the design of thermal garments in the future.
The effectiveness of a reflective surface in combination with fibers as an insulator against heat loss is well known.
Foil-backed fiberglass house insulation is a common application of the principle