JPH02265561A - Catheter - Google Patents

Abstract

PURPOSE:To obtain a catheter having satisfactory strength and flexibility such that braided element wires never protrude into the inner cavity of the catheter by providing a first inner layer consisting of a hard material and a second inner layer consisting of a soft material on the outside to form an inner layer, burying the braided element wires in the second inner layer, and providing an outer layer on the outside thereof. CONSTITUTION:A catheter is formed of a first inner layer consisting of a hard material such as high density polyethylene, a second inner layer 2 consisting of a soft material such as low density polyethylene on the outside, which has braided element wires 4 buried therein, and an outer layer 3 consisting of a soft material such as low density polyethylene on the outside. To manufacture the catheter, the first inner layer 1 is extruded on a core wire to apply a coat, and then the second inner layer 2 is extruded on the outside of the inner layer 1 to apply a coat. Braiding is applied on the outside of the second inner layer 2, and the braided element wires 4 are throttled by a die and buried in the internal part of the second inner layer 2. As the braided element wires 4 are never buried in beyond the hard first inner layer 1, they never protrude into an inner cavity 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a non-coupled vascular catheter of medical tubing.

[Prior Art] Conventionally, in a non-coupled vascular catheter with a medical tube, as shown in FIG. ! It had a two-layer structure: an inner layer 6 in which a wire 8 was embedded, and an outer layer 7 made of the same material as the inner layer 6 but in which no braided wire was embedded. Further, both the inner layer 6 and the outer layer 7 are usually made of soft plastic such as low density polyethylene.

[Problems to be Solved by the Invention] In the conventional catheter, the inner layer 6 had a single layer structure of soft plastic as shown in FIG. There was a risk that the braided wire 8 would jump out into the inner cavity 9 when it was squeezed with a die (not shown) and embedded in the inner layer 6 .

Furthermore, inner layer 6. Since both the outer layer 7 are made of the same material, there was a dilemma of two rules: if the catheter was made to be strong, it would become hard, and if it was made to be soft, it would be made weak.

That is, as described above, in the conventional technology, there was a problem in that the catheter could not satisfy "strength" and "flexibility" at the same time.

An object of the present invention is to provide a catheter that does not allow the braided wire to protrude into the lumen of the catheter and that satisfies "strength" and "flexibility" at the same time.

[Means for Solving the Problems] In the present invention, the inner layer of the catheter includes a first inner layer made of a hard material such as high-density polyethylene, and a second inner layer made of a soft material such as soft polyethylene provided outside the first inner layer. It has a two-layer structure with an inner layer, and a braided wire is embedded in the second inner layer, and an outer layer is further provided outside the inner layer.

[Function] Therefore, the presence of the first inner layer can prevent the braided wire from jumping out into the lumen of the catheter during catheter manufacture. In addition, 2N of hard inner layer and soft inner layer
structure, which makes the catheter “strength J”
and [flexibility J can be satisfied at the same time.

[Example] Hereinafter, the present invention will be described in detail based on the drawings. 1st
The figure is a cross-sectional view showing the configuration of the catheter. That is,
A first inner layer 1 made of a hard material such as high-density polyethylene, and a second inner layer N2 made of a soft material such as low-density polyethylene and having a braided wire 4 embedded therein are provided on the outside thereof, and a second inner layer 1 made of a soft material such as low-density polyethylene is provided on the outside thereof, and It is composed of an outer layer 3 made of a soft material such as.

The method for manufacturing this catheter is as follows: 1. A first inner layer 1 is extruded and coated on a core wire (not shown), and then a second inner layer 2 is extruded and coated on the outside of the first inner layer 1. Furthermore, a braid is applied to the outside of the second inner layer 2 by a known method, and the braided strands 4 are squeezed with a die and embedded into the inside of the second inner layer 2.

At this time, since the braided wire 4 is not embedded inside the hard first inner layer 1, the distance between the braided wire 4 and the inner cavity 5 can be maintained at a certain value or more, and the braided wire 4 does not protrude into the inner cavity 5.

Note that the main body of the catheter has the second inner layer 2 as described above.
There is a braid inside the catheter, but there is no braid at the tip of the catheter in order to eliminate the rigidity of the catheter.

As a specific example, the first inner layer 1 is made of high density polyethylene with a density of 0.942. Melt index MI0.2
The thickness should be 0.05mm to 0.15m.
Let it be m. On top of that, a second inner layer 2 with a density of 0.922.
A low density polyethylene having a melt index of M11.0 is coated to a thickness of 0.1 mm to 0.2 mm. On top of that, according to the known example, stainless steel 5US304 with a wire diameter of 0.06 mm
The SUS strands 4 are braided at a pitch of about 6 mm with 16 strokes and 2 wires, and are intermittently embedded. At that time, the SUS wires 4 have a thickness of 0.056 mm to 0.5 mm, as shown in Fig. 1. 1
Since there is a first inner layer l of high density polyethylene of 5 mm,
A certain distance or more is always maintained between the inner cavity 5,
There is no risk that the wire 4 will jump out into the lumen 5, and the subsequent steps are the same as those of the known example.

Furthermore, as another example, by forming the outer layer 3 with a material different from the second inner layer, a three-layer structure of three types of materials can be used to create a catheter with more ideal "strength J" and "flexibility J". It can be manufactured.

[Effects of the Invention] According to the present invention, a safe and sanitary catheter can be obtained because the braided wire does not protrude into the catheter lumen.

Furthermore, by using a variety of materials and a multilayer structure, a catheter with ideal "flexibility" and "strength" can be obtained that can meet the detailed needs of the user.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the catheter of the present invention; FIG. 2 is a cross-sectional view of a conventional catheter. l...first inner layer 2... 3... 4... 5... second inner layer outer layer Braided wire lumen

Claims (2)

[Claims] (1) The inner layer of the catheter is composed of a first inner layer made of a hard material such as high-density polyethylene, and a second inner layer made of a soft material such as low-density polyethylene provided outside the first inner layer, and the second inner layer is made of a soft material such as low-density polyethylene. A catheter characterized in that it has a structure in which a braided wire is embedded in an inner layer, and further has an outer layer provided outside the second inner layer. (2) The catheter according to claim 1, wherein the second inner layer and the outer layer are made of different materials.