U.S. patent application number 10/950626 was filed with the patent office on 2005-04-14 for medical long object and method for producing the same.
Invention is credited to Fujimagari, Hideki, Iwami, Jun.
Application Number | 20050080358 10/950626 |
Document ID | / |
Family ID | 18807025 |
Filed Date | 2005-04-14 |
United States Patent
Application |
20050080358 |
Kind Code |
A1 |
Iwami, Jun ; et al. |
April 14, 2005 |
Medical long object and method for producing the same
Abstract
A medical long object of the present invention has a part made
of a polymeric material containing a laser color developing agent
at least in a part of the surface thereof, and a light developing
portion formed in the part by color development of the laser color
developing agent due to irradiation with laser light.
Inventors: |
Iwami, Jun; (Shizuoka,
JP) ; Fujimagari, Hideki; (Shizuoka, JP) |
Correspondence
Address: |
Matthew L. Schneider
BURNS, DOANE, SWECKER & MATHIS, L.L.P.
P.O. Box 1404
Alexandria
VA
22313-1404
US
|
Family ID: |
18807025 |
Appl. No.: |
10/950626 |
Filed: |
September 28, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10950626 |
Sep 28, 2004 |
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09984611 |
Oct 30, 2001 |
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6811958 |
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Current U.S.
Class: |
600/585 ;
604/93.01 |
Current CPC
Class: |
B41M 5/267 20130101;
Y10S 430/146 20130101; A61M 25/0009 20130101; A61M 25/0108
20130101; A61M 25/00 20130101; A61M 2025/0008 20130101; A61M
2025/006 20130101 |
Class at
Publication: |
600/585 ;
604/093.01 |
International
Class: |
A61B 005/00; A61M
025/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 30, 2000 |
JP |
2000-330522 |
Claims
What is claimed is:
1. A medical long object, comprising: at least a part of a surface
of a medical long object with a polymeric material containing a
laser color developing agent and only a portion of the surface of
the medical long object in which a color is to be developed by
irradiating with laser light to allow the laser color developing
agent to develop a color and to form unevenness pattern on the
surface; and a coating of a hydrophilic polymer on the part of the
surface of the medical long object which includes the
unevenness.
2. A medical long object according to claim 1, wherein the laser
color developing agent contains mica and/or a compound thereof.
3. A medical long object according to claim 1, which is a guide
wire.
4. A medical long object according to claim 1, which is a
catheter.
5. A medical long object, comprising: a core wire, and at least a
part of a surface of the core wire with a polymeric material layer
containing a laser color developing agent and a color developing
portion formed in the part by color development of the laser color
developing agent due to irradiation with laser light, wherein the
thickness of the polymeric material layer is varied depending upon
a site.
6. A medical long object according to claim 5, wherein the laser
color developing agent contains mica and/or a compound thereof.
7. A medical long object according to claim 5, which is a guide
wire.
8. A medical long object according to claim 5, which is a catheter.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a medical long object
having a mark on its surface.
[0003] 2. Description of the Related Art
[0004] In observation of a biological lumen or the like using an
endoscope, in order to guide the endoscope to a predetermined
position of the biological lumen or the like, a guide wire is used.
The guide wire is inserted to the predetermined position of the
biological lumen or the like before guiding the endoscope.
[0005] If the guide wire is monochromic, the movement thereof is
not recognized even when it is moving in an axial direction.
Therefore, it is preferable that a mark representing a position and
the like of the guide wire is provided on the surface thereof.
[0006] Therefore, conventionally, a method for providing various
marks has been proposed.
[0007] For example, JP 09-501593 A discloses a method for attaching
a hollow tube to a guide wire. According to this method, a hollow
tube made of Teflon or the like and having a plurality of colored
streaks is shrunk over a core wire of a guide wire so as to wrap
it.
[0008] In the above-mentioned method, a mark is provided
simultaneously with the formation of the guide wire. Therefore, it
is difficult to provide a mark at a desired position. Furthermore,
the shape and width of a mark may become uniform as a whole.
[0009] JP 04-108556 U discloses a method for forming a mark by
printing.
[0010] The above-mentioned method has the following problems. Since
ink has no solvent resistance, it is difficult to provide a
lubricating coat such as a hydrophilic polymer to the surface of a
guide wire after forming a mark. It is also difficult to conduct
marking on a curved surface. A time for drying ink is also
required. During use, ink may peel off to flow into a living
body.
[0011] In order to solve the problems of the above-mentioned method
using printing, JP 06-63054 U discloses a method for providing a
transparent coating layer made of fluorine resin after printing a
mark.
[0012] According to this method, a process of drying ink is
required, which complicates production processes. Furthermore,
there is a constraint in terms of design that transparent resin can
only be used.
[0013] Furthermore, U.S. Pat. No. 4,951,686 discloses a method for
heating a site of a catheter guide wire made of steel, in which a
color mark is to be formed, at a temperature allowing a temper
color to appear.
[0014] According to this method, only a catheter guide wire made of
steel can be used. Furthermore, a superelastic alloy (Ni--Ti alloy)
generally used as a core wire of a guide wire is likely to have its
physical properties changed by heat treatment such as heating.
Therefore, this method is not preferable.
[0015] U.S. Pat. No. 4,951,686 also discloses a method for forming
marks by stamping or irradiation with laser light.
[0016] According to the former method, a mark portion to be formed
may be raised, and according to the latter method, a mark portion
to be formed may be recessed, and thus obtained mark is less
visible since the mark has no color change.
[0017] Thus, there is a demand for a guide wire without having the
above-mentioned problems.
[0018] The above-mentioned problems are not limited to guide wires.
For example, in catheters, information such as a scale (length from
a tip end, etc.) is printed on a surface. Therefore, the catheters
also have the same problems as those in the guide wires.
SUMMARY OF THE INVENTION
[0019] Therefore, with the foregoing in mind, it is an object of
the present invention to provide a medical long object which has a
mark with any shape and width at a desired position on its surface
and is excellent in solvent resistance, and in which a mark
position can be curved, there is no possibility of peeling of a
mark during use, various materials such as a superelastic alloy
(Ni--Ti alloy) can be used as a core wire, and a mark is easily
visible since it has little raised or recessed.
[0020] Furthermore, it is another object of the present invention
to provide a method for producing a medical long object, in which a
time for drying ink is not required, and production processes are
not complicated.
[0021] More specifically, the present invention provides a medical
long object including a part formed of a polymeric material
containing a laser color developing agent at least in a part of a
surface, and a color developing portion formed in the part by color
development of the laser color developing agent due to irradiation
with laser light.
[0022] In particular, the present invention provides a medical long
object having a tip end portion and a base end portion, including a
polymeric material surface formed of a polymeric material
containing a laser color developing agent at least in the tip end
portion, and a light developing portion formed by color development
of the laser color developing agent due to irradiation with laser
light on the polymeric material surface.
[0023] It is preferable that the laser color developing agent
contains mica and/or a compound thereof.
[0024] In one preferred embodiment of the present invention, the
above-mentioned medical long object is a guide wire.
[0025] In one preferred embodiment of the present invention, the
above-mentioned medical long object is a catheter.
[0026] Furthermore, the present invention provides a method for
producing a medical long object, including: forming at least a part
of a surface of a medical long object with a polymeric material
containing a laser color developing agent; and irradiating only a
portion of the surface of the medical long object in which a color
is to be developed with laser light so as to allow the laser color
developing agent to develop a color, thereby forming any pattern on
the surface of the medical long object.
[0027] It is preferable that the laser color developing agent is
contained 0.01 to 10% by mass on the total amount of the polymeric
material component.
[0028] These and other advantages of the present invention will
become apparent to those skilled in the art upon. reading and
understanding the following detailed description with reference to
the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] In the accompanying drawings:
[0030] FIG. 1 is a conceptual diagram showing an example of a
method for irradiating laser light in production of a guide wire
that is a medical long object of the present invention;
[0031] FIGS. 2A to 2D show specific examples of a pattern on the
surface of each guide wire; and
[0032] FIGS. 3E and 3F are plan views of medical long objects
(guide wires) produced in Example 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] Hereinafter, the present invention will be described in
detail with reference to the drawings.
[0034] A medical long object of the present invention has a part
made of a polymeric material containing a laser color developing
agent at least in a part of its surface.
[0035] Examples of a polymeric material used in the present
invention include resin, rubber, and the like. Examples of the
resin include polyurethane, polyethylene, polypropylene, an
ethylene-propylene copolymer, fluorine resin (e.g.,
polytetrafluoroethylene), polyethylene terephthalate, polyvinyl
chloride, polyamide, polyimide, an ethylene-vinyl acetate
copolymer, an ethylene-ethyl acrylate copolymer, silicone,
polycarbonate, a styrene-butadiene copolymer, ABS resin,
polyisoprene, and polybutadiene. Of those, polyurethane is
preferable.
[0036] These materials may be used alone or in combination.
[0037] There is no particular limit to a laser color developing
agent used in the present invention, as long as it develops a color
by irradiation with laser light. It is preferable that the laser
color developing agent contains mica and/or a compound thereof.
When the laser color developing agent containing mica and/or a
compound thereof is used, there are the following advantages: a
laser color developing agent develops a color sufficiently only by
being contained in a polymeric material in a small amount, a color
developing portion is hardly raised or recessed, since the content
of a laser color developing agent may be small, a change in a color
of a non-color developing portion can be suppressed, and the
like.
[0038] Note that the term "color development" used in the present
specification also includes all the perceivable changes in a color
such as discoloration, decolorization, and fading in addition to
color development.
[0039] Examples of the laser color developing agent containing mica
and/or a compound thereof include natural mica such as mica
belonging to muscovite series (e.g., muscovite, lepidolite,
paragonite, sericite, roscoelite, illite), mica belonging to
biotite series (e.g., biotite, phlogopite, lepidolite,
zinnwaldite), glauconite, celadonite, muscovite, phlogovite,
suzolite, paragonite, and vermiculite; synthetic mica
(specifically, Iriodin LS-800 produced by Merck Japan Co., Ltd.
having a particle diameter of 15 .mu.m or less, Iriodin LS-805
produced by Merck Japan Co., Ltd. having a particle diameter of 2
to 100 .mu.m); a composition (hereinafter, referred to as "Mica
composition 1". More specifically, Iriodin LS-820 produced by Merck
Japan Co., Ltd. having a particle diameter of 15 .mu.m or less)
composed of mica, titanium oxide, silicon oxide, and tin oxide
doped with antimony oxide; a composition (hereinafter, referred to
as "Mica composition 2". More specifically, Iriodin LS-825 produced
by Merck Japan Co., Ltd. having a particle diameter of 15 .mu.m or
less) composed of mica and tin oxide doped with antimony oxide; a
composition (hereinafter, referred to as "Mica composition 3". More
specifically, Iriodin LS-810 produced by Merck Japan Co., Ltd.
having a particle diameter of 2 to 28 .mu.m) composed of mica and
titanium oxide; a composition (hereinafter, referred to as "Mica
composition 4". More specifically, Iriodin LS-830 produced by Merck
Japan Co., Ltd. having a particle diameter of 10 to 60 .mu.m)
composed of mica, titanium oxide, and iron oxide; and a composition
(hereinafter, referred to as "Mica composition 5". More
specifically, Iriodin LS-835 produced by Merck Japan Co., Ltd.
having a particle diameter of 15 .mu.m or less) composed of mica
and iron oxide. Of those, Mica compositions 1 and 2 are
preferable.
[0040] These laser color developing agents may be used alone or in
combination.
[0041] The content of the laser color developing agent in the
polymeric material is varied depending upon the kind of the laser
color developing agent, the color of the polymeric material, and
the like. In general, the content of the laser color developing
agent is preferably 0.01 to 10% by mass, more preferably 0.1 to 2%
by mass based on the total amount of the polymeric material
component. The color tone after irradiation with laser light can be
regulated by the content of the laser color developing agent.
[0042] In the case of using Mica composition 1 and/or 2, in
particular high color development can be obtained with a small
content thereof. More specifically, when the mica composition is
contained in the polymeric material component in an amount of 0.01
to 2% by mass, more preferably 0.1 to 1% by mass, high color
development can be obtained.
[0043] Additives other than the laser color developing agent (e.g.,
a filler, a pigment, a dye, an antiaging agent, an antioxidant, an
anti-static agent, a lubricant, a plasticizer, a thermal
stabilizer, X-ray contrast medium) can be added to the polymeric
material used in the present invention in such a manner as not to
impair the objects of the present invention.
[0044] The medical long object of the present invention only needs
to have a part made of a polymeric material containing a laser
color developing agent in any part of the surface. In the case
where the medical long object of the present invention has a tip
end portion and a base end portion, it is one preferred embodiment
that the above-mentioned part is provided at least in the tip end
portion of the surface. If there is a mark in the tip end portion
of the surface, it becomes easy to manipulate the medical long
object, and information on the length from the tip end and the like
can be displayed.
[0045] More specifically, in one preferred embodiment of the
present invention, a medical long object has a tip end portion and
a base end portion, the medical long object being characterized by
including a polymeric material surface made of a polymeric material
containing a laser color developing agent at least in the tip end
portion, and has a color developing portion formed by color
development of the laser color developing agent due to irradiation
with laser light on the polymeric material surface.
[0046] According to the present invention, the entire surface of
the medical long object or the entire medical long object may be
made of a polymeric material containing the above-mentioned laser
color developing agent.
[0047] In the case where only a part of the surface of the medical
long object is made of a polymeric material containing a laser
color developing agent, a material of the other part is not
particularly limited, and appropriately selected in accordance with
the use of the medical long object.
[0048] Furthermore, in order to enhance the slidability with
respect to a biological lumen and the like, the surface of the
medical long object of the present invention may be coated with a
low-friction material, whereby the medical long object has its
friction reduced and can be smoothly inserted into a biological
lumen or the like, thus operability and safety thereof are
enhanced.
[0049] An example of the low-friction material includes a
hydrophilic polymer.
[0050] Examples of the hydrophilic polymer include natural
polymeric materials (e.g., starches, celluloses, polysaccharides,
protein), and synthetic polymeric materials (e.g., PVA,
polyethylene oxides, acrylic acids, maleic anhydrides, phthalic
acids, water-soluble polyester, (meth)acrylamides, polyamines,
water-soluble nylons type). Of those, in particular, cellulose type
polymeric materials (e.g., hydroxypropylcellulose), polyethylene
oxide type polymeric materials (e.g., polyethylene glycol), maleic
anhydride type polymeric materials (e.g., maleic anhydride
copolymer such as a copolymer of methyl vinyl ether and maleic
anhydride), acrylamide type polymeric materials (e.g.,
polydimethylacrylamide), and water-soluble nylon (e.g., AQ-nylon
P-70 produced by Toray Industries, Inc.). This is because their
derivatives with a low friction coefficient can be obtained
stably.
[0051] In the case where the surface of the medical long object of
the present invention is coated with a low-friction material, among
the hydrophilic polymers described-above, those which are
transparent or semi-transparent are used so that a light developing
portion on the surface can be observed from outside even if being
coated.
[0052] The medical long object of the present invention has, in a
part made of a polymeric material containing a laser color
developing agent, a color developing portion formed by color
development of the laser color developing agent due to irradiation
with laser light.
[0053] Laser light used for irradiation is selected in accordance
with a laser color developing agent. Examples of the laser light
include near-infrared laser light such as Nd--YAG laser light,
near-infrared laser light such as CO.sub.2 laser light, and excimer
laser light.
[0054] The Nd--YAG laser light can be near-infrared ray with a
wavelength of 1.06 .mu.m, which can be obtained by irradiating a
YAG (yttrium aluminum garnet) lot with light of an arc lamp.
[0055] CO.sub.2 laser light is far infrared ray with a wavelength
of 10.6 .mu.m, which can be obtained by applying a high frequency
(RF) and a high voltage (TEA) to a tube in which CO.sub.2 mixed gas
is filled, thereby exciting the CO.sub.2 mixed gas.
[0056] In the case where the above-mentioned mica (those which have
a particle diameter of 15 .mu.m or less; those which have a
particle diameter of 2 to 100 .mu.m) and the above-mentioned Mica
composition 3 are used as a laser color developing agent, CO.sub.2
laser light among the above-mentioned laser light is preferable. In
the case where the Mica compositions 1 and 2 are used, YAG laser
light is preferable. In the case where the above-mentioned Mica
compositions 4 and 5 are used, CO.sub.2 laser light or YAG laser
light are preferable.
[0057] For example, in the case of Nd--YAG laser light, the
irradiation amount of laser light is preferably in a range of 1.8
to 2.0 kW as an energy output of an irradiation origin,
[0058] Laser is not particularly limited. For example,
conventionally known laser such as those of scanning type, dot
type, and mask type can be used.
[0059] In the scanning type, laser light emitted from an oscillator
is scanned in an X-Y direction by two rotation mirrors, and then
condensed with a lens, and radiated. According to this type, laser
light is radiated while a medical long object is allowed to stand
still, so that marking with any shape can be conducted.
[0060] In the dot type, laser light is tuned to a polygon mirror
rotated at a high speed, and is radiated. High-speed marking can be
conducted.
[0061] In the mask type, laser light passes through a patterned
mask (stencil) and a condensing lens to be radiated. High-speed
marking and marking with a fine pattern can be conducted.
[0062] These lasers can be appropriately selected in accordance
with the use and the like of a medical long object.
[0063] Due to irradiation with laser light, a laser color
developing agent contained in a polymeric material develops a color
to form a color developing portion. Because of this, the surface of
the medical long object can be provided with a mark. For example, a
plurality of marks can be formed at desired positions over the
length by irradiation with laser light.
[0064] Examples of a mark include a letter, a number, a pattern, a
design, and the like. By selecting a laser color developing agent,
a mark can be formed in monochrome or color.
[0065] The size, shape, and the like of the medical long object of
the present invention can be appropriately determined in accordance
with the use and purpose.
[0066] The medical long object of the present invention can be
used, for example, as a guide wire and a catheter.
[0067] A guide wire and a catheter have a curved surface.
Therefore, it is difficult to apply the conventional method for
forming a mark to a guide wire and a catheter.
[0068] Therefore, a guide wire and a catheter are included in one
preferred embodiment of the medical long object of the present
invention.
[0069] The case will be described where the medical long object of
the present invention is a guide wire.
[0070] As long as the guide wire of the present invention has a
part made of a polymeric material containing a laser color
developing agent at least in a part of the surface thereof, and has
a color developing portion formed in the part by color development
of the laser color developing agent due to irradiation with laser
light, there is no particular limit to the guide wire, and a known
shape, structure, and the like can be adopted.
[0071] A core wire used in the guide wire of the present invention
is a line material having flexibility. A constituent material for
the core wire is not particularly limited, and various plastics and
various metals can be used. However, it is preferable that the core
wire is made of a superelastic alloy. Because of this, a guide wire
excellent in torque transferability and kink (bending) resistance
can be obtained without increasing the diameter of the guide
wire.
[0072] Herein, a superelastic alloy is generally called a
shape-memory alloy, which refers to an alloy exhibiting
superelasticity at a service temperature. Superelasticity refers to
a property of metal in which even if ordinary metal is deformed
(bent, pulled, compressed) to plastic deformation at a service
temperature, i.e., at least a temperature of a living body (in the
vicinity of 37.degree. C.), the metal is restored to substantially
the original shape. Examples of a preferable composition of a
superelastic alloy include superelastic body such as a Ti--Ni alloy
containing 49 to 58% by atom of Ni, a Cu--Zn alloy containing 38.5
to 41.5% by mass of Zn, a Cu--Zn--X alloy (where X is at least one
selected from Be, Si, Sn, Al, and Ga) containing 1 to 10% by mass
of X, and an Ni--Al alloy containing 36 to 38% by atom of Al. Among
them, the Ti--Ni alloy is preferable.
[0073] Although not particularly limited, the diameter of a core
wire used. in the guide wire of the present invention is preferably
in a range of 0.25 to 1.57 mm, more preferably in a range of 0.4 to
0.97 mm.
[0074] It is preferable that the tip end portion of the core wire
is tapered in accordance with characteristics such as touch
resistance, bend resistance, and the like, and its outer diameter
is gradually reduced toward the tip end. Because of this, when the
guide wire is inserted into a biological lumen or the like from the
tip end side so as to reach an intended site (lesion), when the
guide wire can flexibly follow a complicated shape such as a curve
and a branch of the biological lumen, whereby the guide wire can be
easily and safely inserted into and removed from the lumen.
[0075] The guide wire of the present invention is obtained by
coating at least a part of the surface of the above-mentioned core
wire with a polymeric material containing a laser color developing
agent.
[0076] Although the thickness of a coating layer is not
particularly limited, it is preferably 0.05 to 0.3 mm on the
average, more preferably 0.1 to 0.2 mm on the average.
[0077] Furthermore the thickness of the coating layer may be
uniform over the entire layer or may be varied depending upon a
site. For example, it may have taken structure that the thickness
of the coating layer may be increased in the vicinity of the tip
end portion of the guide wire.
[0078] Note that the number of coating layers is not limited to
one, and a plurality of stacked coating layers may be used.
[0079] The guide wire is generally used to be inserted into and
held in a living body under X-ray fluoroscopy. Therefore, it is
preferable that the guide wire body is provided with an X-ray
contrast property. That is, it is preferable that an X-ray contrast
medium is contained in a constituent material of the guide wire
body. Examples of the X-ray contrast medium include metal or a
metal compound such as platinum, silver, tungsten, barium sulfate,
and bismuth oxide.
[0080] The case will be described where the medical long object of
the present invention is a catheter.
[0081] As long as the catheter of the present invention has a part
made of a polymeric material containing a laser color developing
agent at least in a part of the surface thereof, and has a color
developing portion formed in the part by color development of the
laser color developing agent due to irradiation with laser light,
there is no particular limit to the catheter, and a known shape,
structure, and the like can be adopted.
[0082] As long as the catheter of the present invention has a part
made of a polymeric material containing a laser color developing
agent at least in a part of the surface thereof, the other part may
be made of a material with flexibility, such as polyvinyl chloride,
polyurethane, polyethylene, polypropylene, polyamide,
polytetrafluoroethylene, silicone rubber, and an ethylene-vinyl
acetate copolymer. The polymeric material used in a part made of a
polymeric material containing a laser color developing agent may be
the same as or different from the polymeric material used in the
other part. By appropriately selecting the above-mentioned
material, the diameter of the catheter body, and the like, the tip
end portion of the catheter has flexibility to such a degree as to
be easily bent when pulled by a wire described later.
[0083] Furthermore, by burying or by coating a reinforcing member
made of a polymeric material (e.g., hard polyurethane and
polyimide) or metal (e.g., a coil spring) in a part of the catheter
body except for the tip end portion, the stiffness of the part of
the catheter body excluding the tip end portion can be enhanced
compared with that of the tip end portion.
[0084] Note that he catheter is generally used to be inserted into
and held in a living body under X-ray fluoroscopy. Therefore, it is
preferable that the catheter body is provided with an X-ray
contrast property. That is, it is preferable that an X-ray contrast
medium is contained in a constituent material of the catheter body.
Examples of the X-ray contrast medium include metal or a metal
compound such as the above-mentioned platinum, silver, tungsten,
barium sulfate, or bismuth oxide.
[0085] The catheter body may be provided with various lumens having
different uses and functions as described below.
[0086] For example, there is a lumen in which an optical fiber
bundle that functions as observation equipment (fiber scope) for
observing an inside of a body cavity such as a blood vessel and a
tubular organ is accommodated. Note that the optical fiber bundle
can also be used for medical treatment such as irradiation with
laser light to a blood vessel and an inner wall of a tubular
organ.
[0087] There is also a lumen that is opened at the tip end portion
of the catheter body in such a manner that fluid can be injected
into a body cavity or the like through the opening or fluid can be
aspired from the body cavity or the like.
[0088] Furthermore, there is a lumen for accommodating a wire for
pulling the tip end of the catheter body so as to curve the tip end
portion of the catheter body.
[0089] Note that one or two more expandable body such as a balloon
that can be expanded by injecting an operation fluid may be
disposed in the vicinity of the tip end portion of the catheter
body and on the base end side from a curved point of the tip end
portion. In this case, a lumen communicated with the expandable
body is formed in the catheter body so as to feed the operation
fluid to the expandable body.
[0090] The shape, structure, and the like of the catheter of the
present invention are varied depending upon the purpose of the
catheter.
[0091] For example, in the case of a epidural catheter, the outer
diameter is preferably 0.6 to 1.5 mm, more preferably 0.8 to 1.2
mm, and the inner diameter is preferably 0.3 to 0.9 mm, more
preferably 0.4 to 0.6 mm. Furthermore, in the case of a vascular
catheter, the outer diameter is preferably 0.8 to 2.5 mm, and the
inner diameter is preferably 0.3 to 2.0 mm. Furthermore, in the
case of a contrast catheter, the outer diameter is preferably 2.7
mm or less, more preferably 2.0 mm or less, and the inner diameter
is preferably 0.9 to 1.8 mm, more preferably 1.0 to 1.5 mm. By
prescribing the inner diameter and the outer diameter in such a
range, the catheter can sufficiently exhibit flexibility and a
following property with respect to a curve.
[0092] Furthermore, the catheter of the present invention may have
a one-layer tube structure or two-layer tube structure.
[0093] According to the method for producing a medical long object
of the present invention, at least a part of the surface of the
medical long object is made of a polymeric material containing a
laser color developing agent, and only the part of the surface of
the medical long object in which a color is to be developed is
irradiated with laser light to allow the laser color developing
agent to develop a color, whereby any pattern is formed on the
surface of the medical long object.
[0094] Hereinafter, the method for producing a medical long object
will be specifically described by exemplifying the case where the
medical long object of the present invention is a guide wire for an
endoscope. It should be noted that the method for producing a
medical long object of the present invention is used not to be
limited to a guide wire for an endoscope.
[0095] (1) First, a laser color developing agent and another
additive, if required, are added to a polymeric material, and its
mixture is kneaded so that the additives are uniformly dispersed in
the material.
[0096] (2) Then, a core fiber (e.g., made of a Ni--Ti alloy) is
coated with the resultant polymeric material containing a laser
color developing agent. The coating method is not particularly
limited. For example, extrusion molding, injection molding, insert
injection molding, and press molding can be used.
[0097] (3) Thereafter, the surface made of the polymeric material
containing a laser color developing agent is irradiated with laser
light in accordance with the laser color developing agent, thereby
allowing the laser color developing agent to develop a color and
forming a mark.
[0098] FIG. 1 is a conceptual diagram showing an example of a laser
light irradiation method in production of the medical long object
of the present invention. In FIG. 1, reference numeral 1 denotes a
medical long object (guide wire), 2 denotes lasers, and 3 denotes
laser light. In FIG. 1, the guide wire 1 moves in an arrow
direction between two lasers 2 and is irradiated with the laser
light 3.
[0099] As shown in FIG. 1, when the guide wire 1 is irradiated with
the laser light 3 while the guide wire 1 is being moved, since the
laser color developing agent is uniformly present on the surface of
the guide wire 1, marking can be conducted at any place and in any
shape by regulating an irradiation direction, an irradiation time,
and the like. For example, a pattern such as a letter and
complicated graphics can be easily formed. FIGS. 2A to 2D show four
specific examples of marking. In FIGS. 2A to 2D, reference numeral
4 denotes color developing portions and 5 denotes non-color
developing portions. The color developing portions 4 and the
non-color developing portions 5 form a pattern.
[0100] As shown in FIG. 1, when the laser light 3 is radiated from
two directions by using two lasers 2, marking can be also conducted
on the periphery of the guide wire 1. Note that the laser
irradiation method is not particularly limited to the above.
[0101] Although, marking can be conducted at any place on the guide
wire in according with its use, in case of the guide wire for an
endoscope, it is preferable that the tip end of marking is placed
at 1 to 7 centimeters base end side from the tip end of guide wire
1, the base end of marking is placed at 15 to 70 centimeters base
end side from the tip end of guide wire 1.
[0102] In prescribing place and length of the marking as mentioned
above, it gives the following advantage. First of all, by
conducting a marking only a portion at base end side of the guide
wire, an operator can easily distinguish between the tip end and
the base end of guide wire.
[0103] Furthermore, in case of the guide wire for an endoscope,
various catheters for treatment, such as EST knife, drainage
catheter, stent delivery catheter, balloon dilation catheter and
like, are operated under observation using an endoscope,. with tip
end of guide wire projected from the tip end of endoscope by dozens
centimeters. The operation that mentioned above includes the
operation for replacing a catheter with others. Therefore, in the
operation, movement of the guide wire must be observed. By
conducting a marking at the projected portion from tip end of the
endoscope, the observation can be done easily. A little unevenness
may be formed in the marking portion irradiated by laser. By not
conducting a marking at the portion of 1-7 cm from the tip end, the
tip end maintains its flexibility and delicate sense of inserting
motion. Furthermore by not conducting a marking at the portion of
1-7 cm from the tip end, the drawback that the surface coating
described below will cover the marking portion and the marking is
less visible can be avoided. Furthermore, by conducting a marking
at minimum portion as needed, production efficiency should be
enhanced and cost should be minimized.
[0104] (4) Furthermore, if required, the surface of the guide wire
1 is coated with a hydrophilic polymer. A conventionally known
coating method (dipping, etc.) can be used.
[0105] It should be noted that unlike the case where a color
developing portion is formed by printing with ink, a color
developing portion formed with a laser color developing agent is
excellent in solvent resistance. Therefore, a mark is not
eliminated with a solvent used in coating of the hydrophilic
polymer. Furthermore, a time for drying ink (which is necessary in
the method of printing with ink) is not required, and coating of a
hydrophilic polymer can be conducted immediately after irradiation
with laser light.
[0106] Furthermore, according to the above-mentioned method,
coating of the hydrophilic polymer is conducted after irradiation
with laser light. However, it is also possible to conduct
irradiation with laser light after coating of the hydrophilic
polymer.
[0107] It has been conventionally impossible to conduct marking on
a medical long object just before or during operation. However,
depending upon the use and purpose of the medical long object, it
is desired that marking is conducted just before or during
operation to specify the position of a lesion ,etc. In the medical
long object of the present invention, if coating of a hydrophilic
polymer is conducted before irradiation with laser light, it is
also possible to conduct a marking due to irradiation with laser
light which pass through the endoscope on the guide wire which
accommodated in the lumen during operation, which is very useful by
reason of that the length of lesion become observable and like.
[0108] The medical long object of the present invention thus
obtained is provided with a mark at least in a part of the surface
thereof. Therefore, the movement of the medical long object in an
axial direction is recognized, and information on a scale and the
like can be displayed, which is useful. Furthermore, as described
above, there is no possibility that a mark peels off during use.
Furthermore, the medical long object of the present invention does
not have a raise or a recess in a mark portion to be formed, and
has a smooth surface.
EXAMPLES
[0109] Hereinafter, the present invention will be specifically
described by way of illustrative examples. It should be noted that
the present invention is not limited thereto.
Example 1
[0110] First, 0.2 g of Mica composition 1 and 3 g of a blue pigment
were added to 99.8 g of polyurethane resin (ether type), and the
mixture thus obtained was kneaded so that Mica composition 1 and
the blue pigment were uniformly dispersed in the polyurethane
resin.
[0111] Then, a core wire (made of a Ni--Ti alloy, having a diameter
of 0.6 mm) was coated with the resultant resin containing a laser
color developing agent by extrusion molding so as to have an outer
diameter of 0.8 mm, whereby a guide wire was obtained.
[0112] Thereafter, the surface formed of the resin containing a
laser color developing agent was irradiated with YAG laser light by
a laser light irradiation method shown in FIG. 1, whereby a mark
was formed. The movement speed of the guide wire was 300 mm/min.,
and the energy output of an irradiation origin was 1800 W.
[0113] Furthermore, the surface was coated with a maleic anhydride
ethyl ester copolymer by dipping, followed by being dried. Thus, a
medical long object (guide wire) of the present invention was
obtained.
Example 2
[0114] A medical long object (guide wire) of the present invention
was obtained by the same method as that of Example 1, except that
irradiation with laser light was conducted after coating of a
maleic anhydride ethyl ester copolymer in place of conducting
coating of a maleic anhydride ethyl ester copolymer after
irradiation with laser light.
Example 3
[0115] First, 0 to 1 g of Iriodin (laser color developing agent),
30 to 70 g of tungsten, and 0 to 10 g of fluorine powder were added
to 30 to 70 g of polyurethane resin respectively, and the mixture
thus obtained was kneaded so that these components were uniformly
dispersed.
[0116] Then, core wires (made of a Ni--Ti alloy) previously tapered
were coated with the resultant resin containing a laser color
developing agent by extrusion molding so as to have outer diameters
respectively shown in Table 1.
[0117] Each core wire thus obtained was cut in predetermined length
and the core wire was coated (hydrophilic polymer coat portion)
with a hydrophilic polymer (a maleic anhydride ester copolymer) to
a length shown in Table 1 from a tip end portion by dipping.
Thereafter, the surface formed of the resin containing a laser
color developing agent was irradiated with YAG laser light by the
laser light irradiation method shown in FIG. 1, whereby a mark was
formed (visual marker portion). The movement speed of the guide
wire was 300 mm/min., and the energy output of an irradiation
origin was 1800 W.
[0118] Furthermore, the tip end portion was rounded and the
remaining portion was coated (hand part silicon coat portion) with
silicon by dipping to obtain a medical long object (guide wire).
FIGS. 3E and 3F show plan views of medical long objects (guide
wires) produced in Example 3. In FIGS. 3E and 3F, reference numeral
4 denotes a color developing portion, 5 denotes a non-color
developing portion, 6 denotes a visual marker portion, 7 denotes a
hydrophilic polymer coat portion, and 8 denotes a hand part silicon
coat portion.
[0119] Table 1 shows the size and the like of each portion of the
guide wires produced in Example 3.
1TABLE 1 Hydrophilic Guide wire Guide polymer outer wire coat Laser
Laser diameter mm length portion treatment treatment Example (inch)
cm length cm length cm shape 3-1 0.635(0.025) 260 5 10 E
0.635(0.025) 260 50 20 E 0.635(0.025) 260 100 30 E 3-2 0.635(0.025)
450 5 10 E 0.635(0.025) 450 50 20 E 0.635(0.025) 450 100 30 E 3-3
0.889(0.035) 260 5 10 F 0.889(0.035) 260 50 20 F 0.889(0.035) 260
100 30 F 3-4 0.889(0.035) 450 5 10 F 0.889(0.035) 450 50 20 F
0.889(0.035) 450 100 30 F
[0120] The guide wires of the present invention obtained in
Examples 1 to 3 had marks with a desired shape at a desired
position, whereby the movement of the guide wires in an axial
direction was able to be recognized during such as insertion.
Furthermore, marks did not peel off during use. Furthermore, the
guide wires of the present invention had a smooth surface
(cylindrical surface), and a raise and a recess were not present in
the mark portions.
[0121] Unlike the case of printing with ink, marks were not
eliminated with a solvent used for coating of the hydrophilic
polymer. Furthermore, it was possible to conduct coating of the
hydrophilic polymer immediately after irradiation with laser light
(Example 1).
[0122] Furthermore, by optimizing place and length of marking, it
is possible that work efficiency of operator and production
efficiency should be enhanced.
[0123] The medical long object of the present invention is provided
with marks at least in a part of the surface thereof, so that the
movement of the medical long object in an axial direction is
recognized. Furthermore, information on a scale and the like can be
displayed, so that the medical long object of the present invention
is useful. Furthermore, the medical long object of the present
invention has no problems that have not been conventionally
solved.
[0124] According to the method for producing a medical long object
of the present invention, the medical long object of the present
invention can be preferably produced.
[0125] Various other modifications will be apparent to and can be
readily made by those skilled in the art without departing from the
scope and spirit of this invention. Accordingly, it is not intended
that the scope of the claims appended hereto be limited to the
description as set forth herein, but rather that the claims be
broadly construed.
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