PURPOSE: To obtain an excellent interior material rich in soundproof and heat insulating properties and generating no low-grade sound even by the rubbing with a car body by forming a corrugated core material from a nonwoven fabric containing a low m.p. fiber and bonding a surface material composed of a nonwoven fabric to the single surface or both surfaces of the core material.
CONSTITUTION: 10-70wt.% of low m.p. fibers, for example, polyester fibers with an m.p. of 13°C are mixed with high m.p. fibers, for example, polyester fibers with an m.p. of 18°C and the resulting mixture is subjected to needle punching to entangle the fibers and heated within the temp. range from the softening point of the low m.p. fibers to the softening point of the high m.p. fibers and the low m.p. fibers are softened to bond the high m.p. fibers to produce a nonwoven fabric 10. This nonwoven fabric 10 is heated in a heating oven 14 to soften the low m.p. fibers and subjected to cold molding by a toothed roll press 15 to produce a corrugated core material 12 and, after an acrylic adhesive is applied to both surfaces of the core material 12 by roll coaters 16, surface materials 13 each composed of the nonwoven fabric 10 are bonded to both surfaces of the core material under pressure to produce corrugated cardboard 11.
KANO TAKESHI
ASANO TADAO
TAISHIN KOGYO KK