Heat-shrinkable tube having tearable properties

Patent metadata

Field	Value
Publication number	US-12454093-B2
Application number	US-202017427189-A
Country	US
Kind code	B2
Filing date	Jan 30, 2020
Priority date	Jan 31, 2019
Publication date	Oct 28, 2025
Grant date	Oct 28, 2025

Abstract

The disclosure provides a tube which is rarely broken and is stable during the process of the production of a heat-shrinkable tube having tearability in a length direction. The tube includes a melt-processable fluororesin and when the strain of the tube is defined as ε, the stress at the strain is defined as σ (MPa) and the strain ε is put on the horizontal axis and the stress σ is put on the longitudinal axis on a coordinate graph, each of a straight line ab and a straight line cd which are defined by four coordinate points a (0.4,8.8), b(0.4,2.4), c(1.0,9.9) and d(1.0,3.2) on the graph intersects with a mechanical property curve of the tube which is obtained by carrying out a tensile test under the conditions of an ambient temperature of 60° C., an initial chuck-to-chuck distance of 22±0.05 mm and a tensile speed of 5 mm/sec.

First claim

The invention claimed is:

1 . A heat-shrinkable tube having tearability comprising at least a melt-processable fluororesin, wherein
a strain of the tube is represented as ε, a stress at the strain is represented as σ (MPa), a horizontal axis on a coordinate graph is a strain ε, a vertical axis thereon is a stress σ, and in a mechanical property curve of the tube obtained through a measurement method comprising a tensile test being performed under conditions of an ambient temperature of 60° C., an initial chuck-to-chuck distance of 22±0.05 mm, and a tensile speed of 5 mm/sec., the stress σ at the strain of 1.0 is 3.2 MPa or more, and when a coordinate point at the strain ε of 1.0 on the mechanical property curve is represented as e and a coordinate point at the strain ε of 2.0 on the mechanical property curve is represented as f, a slope of a straight line passing through the coordinate point e and the coordinate point f is 2.4 to 3.0 Mpa.

2 . The heat-shrinkable tube having tearability according to claim 1 , wherein the fluororesin comprises at least a resin comprising at least three monomers of tetrafluoroethylene, hexafluoropropylene, and vinylidene fluoride as constituent monomers.

3 . The heat-shrinkable tube having tearability according to claim 2 , wherein the resin comprising at least three monomers of tetrafluoroethylene, hexafluoropropylene, and vinylidene fluoride as constituent monomers is contained in an amount of 25 wt % to 95 wt %.

4 . The heat-shrinkable tube having tearability according to claim 2 , wherein the resin comprising at least three monomers of tetrafluoroethylene, hexafluoropropylene, and vinylidene fluoride as constituent monomers is a copolymer comprising 15 wt % to 25 wt % of vinylidene fluoride.

5 . The heat-shrinkable tube having tearability according to claim 1 , comprising a plurality of fluororesins, wherein a maximum difference in refractive index (ASTM D542) between the plurality of fluororesins is 0.05 or less.

Assignees

• Junkosha Inc

Inventors

• Suzuki Masahiro
• Kimura Yasuyuki

Classifications

• F16L11/12

  with arrangements for particular purposes, e.g. specially profiled, with protecting layer, heated, electrically conducting (F16L11/11 takes precedence) · CPC title

• F16L11/06

  with homogeneous wall (F16L11/11 takes precedence) · CPC title

• A61M25/0009

  Making of catheters or other medical or surgical tubes · CPC title

• A61M25/0662

  Guide tubes · CPC title

• B29L2023/001

  Tubular films, sleeves · CPC title