Laminated non-woven and non-woven fabric made of drain material for drain material

摘要

PROBLEM TO BE SOLVED: To provide a laminated nonwoven fabric for drain material, which hardly causes a loss of the shape and can be processed into a pipe having a desired bore diameter and length at a job site as required.;SOLUTION: A laminated nonwoven fabric for drain material is formed of an integrated laminate of a first fiber layer and a second fiber layer. The first fiber layer has a thermal shrinkage rate SHD₁ of 5% or lower at a temperature of 150°C and a fabric weight of 350 to 2000 g/m². The second fibric layer has a thermal shrinkage rate SHD₂ of 15% or higher at a temperature of 150°C and a fabric weight of 200 to 600 g/m². The difference in the thermal shrinkage rate between the first and second fiber layers (SHD₂-SHD₁) is 10 to 50% at a temperature of 150°C.;COPYRIGHT: (C)2013,JPO&INPIT