Coated fabric products

Abstract

This relates to the coating of air bags, which are used for safety purposes to protect occupants of vehicles such as automobiles, and of air bag fabrics intended to be made into air bags. In particular the invention relates to the top coating of air bags and air bag fabrics which have been pre-coated with a cured organic resin coating composition. The top-coat is an anti-blocking coating composition comprising at least one solid lubricant dispersed in an organic polymer binder. A process for applying the top-coat is also described.

Claims

1. An air bag having a cured coating consisting of an organic resin, wherein the air bag is top coated with an anti-blocking coating comprising at least one solid lubricant dispersed in an organic polymer binder, wherein the anti-blocking coating contains a wetting agent comprising a siloxane polyether having 1-3 alkylpoly(ethyleneoxy)siloxane groups (i) and 1 to 4 alkyl-siloxane groups (ii).

2. An air bag having a cured coating comprising an organic resin, wherein the air bag is top coated with an anti-blocking coating comprising at least one solid lubricant dispersed in an organic polymer binder, wherein the anti-blocking coating contains a wetting agent comprising a siloxane polyether having 1-3 alkylpoly(ethyleneoxy)siloxane groups (i) and 1 to 4 alkyl-siloxane groups (ii).

3. An air bag according to claim 2, wherein the dispersed solid lubricant comprises a fluoropolymer.

4. An air bag according to claim 3, wherein the dispersed solid lubricant comprises polytetrafluoroethylene.

5. An air bag according to claim 4, wherein the dispersed solid lubricant comprises talc.

6. An air bag according to claim 3, wherein the dispersed solid lubricant comprises talc.

7. An air bag according to claim 2, wherein the dispersed solid lubricant comprises talc.

8. An air bag according to claim 2, wherein the solid lubricant is dispersed in a polyurethane binder.

9. An air bag according to claim 2, wherein the anti-blocking coating comprises 3 to 85% solid lubricant on a dry weight basis.

10. An air bag according to claim 2, wherein the anti-blocking coating contains 5 to 55% by weight aluminum trihydrate as flame retardant.

11. An air bag according to claim 2, wherein the coating weight of the anti-blocking coating is 1 to 15 g/m.sup.2 on a dry coat weight basis.

12. An air bag according to claim 2, wherein the dispersed solid lubricant comprises talc, a fluoropolymer, polytetrafluoroethylene, and the solid lubricant is dispersed in a polyurethane binder.

13. A process for coating an air bag or air bag fabric in which the bag or fabric is coated with an organic resin composition, wherein the air bag is top coated with an anti-blocking coating composition comprising an aqueous dispersion of at least one dispersed solid lubricant, wherein the anti-blocking coating composition contains a wetting agent comprising a siloxane polyether having 1-3 alkylpoly(ethyleneoxy)siloxane groups (i) and 1 to 4 alkyl-siloxane groups (ii).

14. A process according to claim 13, wherein the anti-blocking coating composition comprises a dispersion of a solid fluoropolymer in an aqueous dispersion of an organic polymer binder.

15. A process according to claim 13, wherein the anti-blocking coating composition comprises a dispersion of talc in an aqueous dispersion of an organic polymer binder.

16. A process according to claim 15, wherein the organic resin coating comprises a hybrid resin of a urethane polymer blended with an acrylate or vinyl resin, where at least one of the components of the hybrid resin has a glass transition temperature of 20 C. or less.

17. A process according to claim 13, wherein the organic resin coating comprises a urethane polymer.

Description

EXAMPLE 1

(1) An aqueous aliphatic polyurethane dispersion stabilized by non-ionic surfactant was mixed with an aqueous dispersion of PTFE powder stabilized by non-ionic surfactant, and then with talc, aluminum trihydrate, a wetting agent and an adhesion promoter to form an anti-blocking coating composition comprising 50 parts water, 44 parts PTFE, 3.0 parts urethane polymer, 3.0 parts (t-Octylphenoxy)polyethoxyethanol non-ionic surfactant, 2.0 parts 1,1,1,3,5,5,5-heptamethyl-3-polyethoxypropyl-trisiloxane wetting agent, 1.0 part epoxysilane adhesion promoter, 10 parts talc and 20 parts aluminum trihydrate.

(2) The anti-blocking coating composition of Example 1 was applied by gravure roller coating to the coated surface of a woven nylon air bag fabric coated with a coating sold by Milliken & Co. of Spartanburg, S.C., under the trade mark Patina and believed to comprise a hybrid urethane resin comprising urethane polymer blended with an ethylene vinyl acetate copolymer and cured. The anti-blocking coating was heat cured at 140 C. In different experiments, the anti-blocking coating was applied at various coat weights as shown in Table 1.

(3) The fabrics top coated with the anti-blocking coating of Example 1, and three control samples having no top coat, were tested in a blocking test in which 50 mm50 mm coated fabrics were placed face to face and a 20 lb (9 kg) weight was applied while the fabrics were held at 110 C. for 4 hours. At the end of that period, a 50 g force is applied to the corner of one of the fabrics. If the fabrics do not separate in 60 seconds, they are rated as blocked. If the fabrics separate in under 60 seconds, they pass the blocking test (rated IS in Table 1).

(4) The fabrics top coated with the anti-blocking coating of Example 1, and three control samples having no top coat, were also tested in a burn test in which a flame was applied to the edge of the fabric and the distance of burning and time of burning were measured. All the fabric samples were self-extinguishing (SE), most immediately on removal of the flame.

(5) TABLE-US-00001 TABLE 1 Top coat Burn Burn rate weight Blocking distance mm seconds SE or burn 5.0 IS 0 0 SE 1.0 IS 0 0 SE 1.5 IS 3 3 SE 2.2 IS 0 0 SE 3.4 IS 0 0 SE 3.2 IS 0 0 SE 5.5 IS 0 0 SE 4.3 IS 0 0 SE 1.8 IS 0 0 SE 2.4 IS 0 0 SE 1.8 IS 0 0 SE 1.0 IS 0 0 SE 3.6 IS 0 0 SE 3.8 IS 6 8 SE 2.6 IS 0 0 SE 3.4 IS 0 0 SE 0 Block 0 0 SE 0 Block 0 0 SE 0 Block 0 0 SE