Melt blown nonwoven fabric, laminate using same, melt blown nonwoven fabric production method and melt blowing apparatus

Patent metadata

Field	Value
Publication number	US-2020171789-A1
Application number	US-202016784537-A
Country	US
Kind code	A1
Filing date	Feb 7, 2020
Priority date	Aug 10, 2017
Publication date	Jun 4, 2020
Grant date	—

Abstract

Provided are a melt blown (MB) nonwoven fabric, a laminate using the same, a method of producing a melt blown nonwoven fabric as well as a melt blowing apparatus. A melt blowing apparatus 100 includes a die 10 configured to discharge a resin melt 42 with an accompanying jet to give fiber materials, a hollow cover 20, and a collector 60. The fiber materials 50 from the die 10 are heated to a temperature equal to or higher than a crystallization temperature of crystalline thermoplastic resin inside the hollow cover 20 and collected on a collecting surface 62 of the collector 60. The hollow cover 20 and the collector 60 are separated by a distance of 5 cm or longer between a lower edge 28 of the hollow cover 20 and the collecting surface 62 in a line extending downwardly from the nozzle holes 12 in a vertical direction.

First claim

What is claimed is:

1 . A melt blown nonwoven fabric comprising a resin composition including a polyethylene terephthalate-series resin as a principal component, wherein the melt blown nonwoven fabric has a surface shrinkage ratio at 200° C. of 20% or lower and a longitudinal 10% modulus (M MD ) at 30° C. of 22 N/5 cm or lower.

2 . The melt blown nonwoven fabric according to claim 1 , wherein the melt blown nonwoven fabric has a longitudinal tensile strength (T MD ) of 10 N/5 cm or higher and a ratio (T MD /T CD ) of the longitudinal tensile strength (T MD ) to a transverse tensile strength (T CD ) in a range from 1.00 to 1.40.

3 . The melt blown nonwoven fabric according to claim 1 , wherein the melt blown nonwoven fabric has a longitudinal elongation ratio (E MD ) of 25% or higher and a ratio (E MD /E CD ) of the longitudinal elongation ratio (E MD ) to a transverse elongation ratio (E CD ) in a range from 0.80 to 1.20.

4 . The melt blown nonwoven fabric according to claim 1 , wherein the melt blown nonwoven fabric has an air permeability of from 30 to 90 cm 3 /cm 2 ·s in accordance with JIS L 1906.

5 . The melt blown nonwoven fabric according to claim 1 , wherein the melt blown nonwoven fabric is used for an acoustic material for a vehicle.

6 . A laminate comprising a support and a melt blown nonwoven fabric that is thermocompression-bonded to at least one surface of the support, wherein the melt blown nonwoven fabric is a melt blown nonwoven fabric recited in claim 1 .

7 . The laminate according to claim 6 , wherein the laminate has a peeling strength (T-peel test) of 0.2 N/5 cm or higher in accordance with JIS K 6854-3 at a thermocompression-bonded surface between the melt blown nonwoven fabric and the support.

8 . The laminate according to claim 6 , wherein the support is formed of a nonwoven fabric or a felt.

9 . An acoustic material for a vehicle, comprising a laminate recited in claim 6 .

10 . A method of producing a melt blown nonwoven fabric, the method comprising:
heating a resin composition including a crystalline thermoplastic resin to give a melt and discharging the melt with accompanying jet through nozzle holes to give fiber materials; heating the fiber materials discharged through the nozzle holes in a heating zone; exposing the heated fiber materials to outside air in an air gap zone to cool the fiber materials; and collecting the cooled fiber materials on a collecting surface to obtain a web, wherein at least a part of the heating zone is heated to a crystallization temperature of the crystalline thermoplastic resin or higher; and the air gap zone is a space between a lower edge of the heating zone and the collecting surface, the space having a distance L of 5 cm or longer in a line extending downwardly from the nozzle holes in a vertical direction.

11 . The method of producing a melt blown nonwoven fabric according to claim 10 , wherein the heating zone is a space between the nozzle holes and the lower edge of the heating zone, the space having a distance H of 10 cm or longer in the line extending downwardly from the nozzle holes in the vertical direction.

12 . The method of producing a melt blown nonwoven fabric according to claim 10 , wherein the fiber materials have a temperature equal to or higher than the crystallization temperature (Tc)—25° C., at a position 10 cm below the nozzle holes in the vertical direction in the heating zone.

13 . The method of producing a melt blown nonwoven fabric recited in claim 10 , wherein the crystalline thermoplastic resin is a polyethylene terephthalate-series resin.

14 . A melt blowing apparatus at least comprising:
an extruder configured to heat a resin composition including a crystalline thermoplastic resin to give a melt; a die configured to discharge the melt with an accompanying jet to give fiber materials; a hollow cover provided in a downstream side of the accompanying jet and configured to surround the fiber materials; a heating unit configured to heat the fiber materials; a collector having a collecting surface configured to collect the fiber materials flowing from the hollow cover in a downward direction of the accompanying jet, wherein the hollow cover and the collector are separated by a distance of 5 cm or longer between a lower edge of the hollow cover and the collecting surface in a line extending downwardly from the nozzle holes in a vertical direction.

15 . The melt blowing apparatus according to claim 14 , wherein the nozzle holes and the lower edge of the hollow cover are separated by a distance of 10 cm or longer in the line extending downwardly from the nozzle holes in the vertical direction.

16 . The melt blowing apparatus according to claim 14 , wherein the hollow cover is formed with an air blowing port configured to introduce heated air.

Assignees

• Kuraray Co

Inventors

• Okamoto Tetsuya
• Shirotani Yasuhiro

Classifications

• B32B37/04

  characterised by the partial melting of at least one layer · CPC title

• B32B2305/18

  Fabrics, textiles · CPC title

• B32B2307/102

  Insulating · CPC title

• D01D5/08

  Melt spinning methods {(D01D5/0023 takes precedence)} · CPC title

• D04H3/16

  with bonds between thermoplastic filaments produced in association with filament formation, e.g. immediately following extrusion · CPC title