Nonwoven fabric sheet and method for producing same

a nonwoven fabric and fabric technology, applied in the field of nonwoven fabric sheets, can solve the problems of reducing the intrinsic property of nonwoven fabrics having voids therein, reducing the lifetime of filter materials, reducing diffusion performance, heat insulation performance, etc., and achieves uniform pore size distribution, high porosity, and fine pore sizes.

Inactive Publication Date: 2007-08-09
MITSUI CHEM INC
View PDF5 Cites 26 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0007] The nonwoven fabric sheet according to the present invention has a high porosity, relatively fine pore sizes, and a relatively uniform pore size distribution, and thus can be suitably used in various applications such as filters, light diffusion materials, liquid absorbers, and heat insulating materials. The nonwoven fabric sheet according to the present invention has a uniform pore size and thus allows only substances having a certain size to pass through.

Problems solved by technology

Accordingly, when calendering is performed under conditions to obtain a nonwoven fabric with sufficiently small openings, an intrinsic property of nonwoven fabrics of having voids therein is impaired.
It has been pointed out that, when using a nonwoven fabric for light diffusion materials, liquid absorbers, filter materials, heat insulating materials and the like, if the nonwoven fabric has a low porosity, a reduction in diffusion performance, liquid retention performance, lifetime of filter material, heat insulation performance, or the like, is caused.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0041] Polypropylene (manufactured by Polymirae Co., Ltd.; melting point: 150° C.; melt flow rate measured at 230° C. under 2.16 kg load: 1000 g / 10 min) was spun by a melt-blown method at a resin temperature of 300° C. and a spinning air flow of 25 Nm3 / kg (air flow amount used for spinning 1 kg of a resin), and fibers were collected with a web former to obtain a melt-blown nonwoven original fabric with a basis weight of 12 g / m2. The average fiber diameter of the nonwoven original fabric obtained was 2.7 μm. The nonwoven original fabric obtained was pressed with a roll machine having a rubber roller (Young modulus: 200 kg / cm2) at 100° C. and a steel roller at 100° C. The linear pressure was set to 20 kg / cm and the processing speed was set to 10 m / min. A nonwoven fabric sheet having properties shown in Table 1 was obtained. The obtained nonwoven fabric sheet had a large number of small pores and its appearance was white.

example 2

[0042] Polypropylene (manufactured by Polymirae Co., Ltd.; melting point: 150° C.; melt flow rate at 230° C. under 2.16 kg load: 1000 g / 10 min) was spun by a melt-blown method at a resin temperature of 300° C. with a spinning air flow of 40 Nm3 / kg (air flow amount used for spinning 1 kg of a resin), and fibers were collected with a web former to obtain a melt-blown nonwoven original fabric with a basis weight of 12 g / m2. The average fiber diameter of the nonwoven original fabric obtained was 1.8 μm. The nonwoven original fabric obtained was pressed with a roll machine having a rubber roller at 100° C. and a steel roller at 100° C. in the same manner as Example 1. The linear pressure was set to 20 kg / cm and the processing speed was set to 10 m / min. A nonwoven fabric sheet having properties shown in Table 1 was obtained. The obtained nonwoven fabric sheet had a large number of small pores and its appearance was white.

example 3

[0043] Spinning was performed under the same spinning conditions as Example 2 to obtain a melt-blown original fabric with a basis weight of 20 g / m2. The nonwoven original fabric obtained was pressed with a roll machine having a rubber roller at 100° C. and a steel roller at 100° C. in the same manner as Example 1. The linear pressure was set to 20 kg / cm and the processing speed was set to 10 m / min. A nonwoven fabric sheet having properties shown in Table 1 was obtained. The obtained nonwoven fabric sheet had a large number of small pores and its appearance was white.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
pore sizeaaaaaaaaaa
melting pointaaaaaaaaaa
melting pointaaaaaaaaaa
Login to view more

Abstract

The nonwoven fabric sheet of the present invention is characterized by a porosity in the range of 0.3 to 0.7 and an average pore size in the range of 0.5 μm to 5.0 μm. The nonwoven fabric sheet of the present invention preferably has a maximum pore size (μm)/average pore size (μm) ratio of 1.30 or lower. The nonwoven fabric sheet of the present invention is obtained by press-molding a nonwoven fabric at a temperature lower than the melting point of the thermoplastic resin which constitutes the nonwoven fabric sheet. According to the present invention, there is provided a nonwoven fabric sheet that has a high porosity, small uniform pore sizes and excellent productivity, which can suitably be used in various applications such as filters, light diffusing material, liquid absorber and heat insulating materials; and a method for producing the nonwoven fabric sheet.

Description

TECHNICAL FIELD [0001] The present invention relates to a nonwoven fabric sheet with a high porosity and a small uniform pore size, and a method of producing the same. BACKGROUND ART [0002] It has been known that a nonwoven fabric with fine openings can be produced from fibers with a small fiber diameter. One of such methods is calendering a nonwoven fabric using heated rollers, wherein an opening size is decreased by reducing distances between fibers. When a nonwoven fabric is subjected to calendering, however, the thickness is reduced and the porosity of the nonwoven fabric is lowered. Accordingly, when calendering is performed under conditions to obtain a nonwoven fabric with sufficiently small openings, an intrinsic property of nonwoven fabrics of having voids therein is impaired. When heated rollers are used, fibers on the surfaces of a nonwoven fabric are thermally fusion-bonded, and thus the fibers may form a film or the pores may be squashed (for example, see Japanese Patent...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(United States)
IPC IPC(8): D04H13/00D04H1/56B32B3/26B29C41/24B29C43/22B29C43/46D04H3/08D04H3/14D04H3/16D06C15/00
CPCB29C43/22B29C43/46B29C2043/3652D04H3/16D04H3/08D04H3/14B29K2105/0809Y10T428/249953Y10T442/60Y10T442/68
Inventor OKADA, KAZUYASUDOU, YASUHIRO
Owner MITSUI CHEM INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap