Comfort cushioning

Compressive Behavior. The most kiformative data ki characterising the compressive behavior of a flexible foam are derived from the entire load-deflection curve of 0—75% deflection and its return to 0% deflection at the speed experienced ki the anticipated appHcation. Various methods have been reported (3,161,169—172) for relating the properties of flexible foams to desked behavior ki comfort cushioning. Other methods to characterize package cushioning have been reported. The most important variables affecting compressive behavior are polymer composition, density, and cell stmcture and size. 

Latex foam mbber was initially accepted as a desirable comfort-cushioning material because of its softness to the touch and its resiUence (equal to that of a steel spring alone but with better damping quaUties than the spring). 

Examples A, closed cell thermal insulation with high fire retardency and low smoke generation (52,54) B, pigmented APN coatings in aluminum substrates with low flammability, low flame spread, and low smoke (55) C, APN insulation and cable jacketing (56) D, open cell APN comfort cushioning (57). (Photograph courtesy of the Firestone Tire... 

Comfort cushioning is the largest single application of cellular polymers flexible foams are the principal contributors to this field. However, the rapid growth rate of structural, packaging, and insulation applications has brought their volume over that of flexible loams during the past Tew years. Table 5 shows U.S, consumption of foamed plastics by resin and market,... 

Cross-linked polyethylene foams are produced by eilher radiation or chemical cross-linking of an extruded expandable sheet containing a chemical blowing agent. These products have finer texture and a softer, more resilient feel than extruded low density polyethylene foams and are used in comfort cushioning and cushion packaging applicutinns. 

It s easy to envy those adopting this strategy. Frequently these retirees calculate how much money they think they will need for a comfortable cushion. They then invest or bank that sum and relax. Once they have their personal cushion, they cease to worry about money. From that point on they buy necessities, pay bills, and enjoy life, spending whatever their monthly retirement income may be. 

Furniture Transportation Comfort cushioning Carpet underlay Packaging Textiles... 

Dual-Hardness Molded Foam A number of formulations for molded foams have been reported. A new development in recent years is dual-hardness molded foams. Automotive seats and furniture have been labor-intensive products. These products provide good comfort by using different layers of different hardnesses. Molded foams produced by using a single formulation have relatively comfortable cushioning properties in terms of sag factor. However, this advantage is not enough to satisfy customers requirements for comfort. 

In the early 1980 s a neoprene-type foam (VONAR) made by Du Pont was developed specifically for use as a comfort cushioning material for critical applications where low flammabUity was required, such as in transport aircraft seat cushions. This material is designed for use over flame-retardant polymethane foam and is believed to provide 50 seconds more of evacuation time in the event of a post-crash fire. VONAR has a density of 10.66 Ib/ft , compared to 7-8 Ib/ft for standard neoprene foam, and 1.2-2 Ib/ft for polyurethane foam (5). 

This specification primarily relates to the quality of polyurethane foam used for comfort-cushioning purposes. The foam is classified according to performance during a fatigue test, indentation hardness being used as a secondary means of grading the material. 

Flexible Cellular Polymers. The application of flexible foams has been predominantly in comfort cushioning, packaging, and wearing apparel (142,170, 171), resulting in emphasis on a different set of mechanical properties than for rigid foams. The compressive nature of flexible foams (both static and dynamic) is their most significant mechanical property for most uses (Table 3). Other... 

Applications. Flexible cellular poly(vinyl chloride) was developed as a comfort-cushioning material with compression-deflection behavior similar to latex rubber foam, and with the added feature of flame retardancy (37). It has a... 

Shoes High level of comfort, cushioning and sock Absorption Light weight Nontoxicity Good aesthetics Insoles, midsoles, shoe lining, needle pouched insoles... 

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