Abstract: A duct structural member comprises an outer layer based on a material having a structure having a side chain in a molecule and an elasticity of 200 MPa or lower on a test method defined under JIS K7171, of among low polarity elastomers comprising carbon and hydrogen.

Abstract: A pipe-end-connecting joint comprisse a nipple 1 inserted in the pipe end, a holder 2 for tightening the outer circumference of the pipe end, and an elastic packing 3 divided into half parts and attached in the holder 2. The nipple 1 includes a tubular portion 11 provided in one longitudinal end side thereof so as to be inserted in the pipe end, a connection portion 12 provided in the other longitudinal end side thereof so as to be connected to another joint, and a flange portion 13 provided in a longitudinal intermediate portion thereof so as to protrude outward.

Abstract: An excellent laminate applicable to various uses capable of overcoming drawbacks of a foamed polyethylene resin such as weak wear resistance and weak strength, by effectively covering the surface of the foamed polyethylene resin, in which a resin layer containing a graft copolymer of an ethylene-vinyl acetate copolymer resin and a vinyl chloride resin is laminated to a foamed polyethylene resin, and a resin layer containing a graft copolymer of an ethylene-vinyl acetate copolymer resin and a vinyl chloride resin is interposed between the foamed polyethylene resin layer and the vinyl chloride resin layer.

Abstract: There is provided a sound-absorbing and a heat-insulating duct comprising a nonwoven cloth layer 1, a reinforcing core 2, a foam strip layer 3, a bonding resin 4 and resin-coating layer 5. The nonwoven cloth layer 1 is formed by wound spirally a nonwoven cloth 10 into a tube-like shape in which adjacent side edges of the adjacent nonwoven cloths 10 are brought in abutment against or lapped with each other so as to form a bonding portion 1a. The reinforcing core 2 made of hard synthetic resin material is wound spirally on the bonding portion 1a while a surface of the reinforcing core 2 being brought into contact with the nonwoven cloth 10 is welded or bonded to the nonwoven cloth 10. The foam strip layer 3 is formed by wound spirally a foam resin strip 30 having a width approximately equal to a width of the nonwoven cloth 10. Both adjacent edges 3a, 3b of the foam resin strip are disposed on adjacent reinforcing cores 2, 2 respectively.