JP2005218602A - Production method of tube containing contrast medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-quality tube containing a contrast medium excellent in surface nature and durability thereof with higher yields by inhibiting the coagulation of an X-ray contrast medium, and further, a whitening inorganic filler. <P>SOLUTION: In the production method of the tube containing the contrast medium having the X-ray contrast medium contained within the tube wall, the powder of the X-ray contrast medium granulated below 20 μm in particle size and dried is added to a hot melting fluorine resin and after melted and mixed at a temperature above the melting temperature of the hot melting fluorine resin, it is pelletized to make pellets. Then, the pellets thus obtained are molded into a tube. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a tube containing a contrast medium containing an X-ray contrast medium in a tube wall.

  For example, X-ray contrast agents such as barium sulfate and bismuth oxide are made of a polymer material for an indwelling catheter for maintaining communication with the inside of a blood vessel when blood transfusion or infusion is performed, or a catheter for diagnosis or treatment. Conventionally, a contrast agent-containing tube mixed in the tube wall has been used (see, for example, Patent Document 1).

  However, since the X-ray contrast medium is a powder, it easily aggregates, and as shown in the SEM cross-sectional photograph of FIG. It may become a starting point or unevenness may be formed on the surface, which is a major cause of reducing reliability, quality, and yield.

  In addition, bismuth oxide widely used as an X-ray contrast agent is a fairly clear yellow powder, and when mixed with a polymer material as it is and molded, the tube containing the contrast agent also exhibits a clear yellow color. In some cases, a medical member is favorably white. Therefore, a tube containing a contrast medium is whitened by adding a whitening inorganic filler such as titanium oxide. However, since the whitening inorganic filler is a powder, it may be present in the tube wall of the contrast agent-containing tube as an aggregate in the same manner as the X-ray contrast agent.

JP-A-5-154192

  The present invention has been made in view of such a situation. A tube containing a high-quality contrast agent that suppresses aggregation of an X-ray contrast agent and further a whitening inorganic filler, has excellent durability, and has excellent surface properties. It aims at manufacturing with good yield.

  In order to achieve the above object, the present invention is a method for producing a tube containing a contrast agent containing an X-ray contrast agent in the tube wall, wherein the tube is classified into a heat-melting fluororesin to a particle size of 20 μm or less and dried. X-ray contrast agent powder is added, melt-mixed at a temperature equal to or higher than the melting temperature of the heat-meltable fluororesin, pelletized to produce pellets, and then the resulting pellets are formed into a tube shape A method for producing a tube containing a contrast medium is provided.

  According to the present invention, in the preparation of the molding material, the dispersibility of the X-ray contrast agent powder and the whitening inorganic filler is increased, and the resulting contrast agent-containing tube does not have these aggregates in the tube wall and cracks. And the occurrence of breakage is suppressed, the surface is not uneven, and the yield is increased.

  Hereinafter, the present invention will be described in detail.

  In the present invention, a heat-meltable fluororesin is used as a polymer material for a tube containing a contrast agent. Among them, a tetrafluoroethylene-ethylene copolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, and a tetrafluoroethylene are used. -Perfluoroalkoxyethylene copolymers are preferred. These may be used alone or in appropriate combination.

  X-ray contrast agent powder classified to 20 μm or less and dried is added to the above hot-melt fluororesin. By using the classified and dried X-ray contrast agent powder, water of crystallization and adsorbed water are removed and the particle size becomes uniform, so there is no agglomeration before mixing with the hot-melt fluoropolymer, resulting in heat The dispersibility in the meltable fluororesin is increased, and it becomes difficult to form an aggregate even when a tube containing a contrast medium is finally formed. There is no restriction | limiting in the kind of X-ray contrast agent, Well-known things, such as bismuth oxide, bismuth oxychloride, bismuth subcarbonate, bismuth nitrate, bismuth tungstate, barium sulfate, can be used. The lower limit of the particle size is not particularly limited, but is preferably 0.2 μm or more because aggregation tends to occur when the particle size becomes too fine.

  Classification can be easily performed using a sieve or the like. The drying may be performed by placing the X-ray contrast medium powder in a heating furnace at 110 to 130 ° C. and maintaining for 10 to 15 hours.

  The amount of X-ray contrast agent powder added is not limited as long as a practical contrast effect can be obtained, but 5 to 25% by mass of the total amount of the contrast agent-containing tube molding material is appropriate. In particular, when the addition amount exceeds 25% by mass, aggregates of X-ray contrast agent powder are likely to be formed, and furthermore, since the amount of the heat-meltable fluororesin is relatively reduced, the moldability becomes inferior. The contrast-contained tube obtained is also less flexible.

  Further, when bismuth oxide is used as the X-ray contrast agent powder, it is preferable to add 1 to 3% by mass of the whitened inorganic filler powder for the whitening of the total amount of the contrast agent-containing tube molding material. There is no restriction | limiting in the kind of whitening inorganic filler, Well-known things, such as a titanium oxide, can be used. However, it is more preferable to use titanium oxide coated with aluminum oxide as a whitening inorganic filler in order to further improve dispersibility. As the coating method, for example, titanium oxide may be added to an aluminum sulfate aqueous solution, dispersed by stirring, neutralized with aluminum hydroxide, taken out, and heat-treated.

  This whitening inorganic filler is also preferably dried in order to suppress aggregation. The drying method is the same as that for the X-ray contrast medium powder.

  Moreover, in this invention, in order to further improve the dispersibility of X-ray contrast agent powder and whitening inorganic filler powder, a diorganopolysiloxane compound is added. The diorganopolysiloxane compound is a compound having two organic groups on each silicon atom of the siloxane polymer, such as special methylphenylsiloxane (YF-33, manufactured by Toshiba Silicon), dimethylsiloxane (KF-96, Shin-Etsu). Silicon), polydimethylsiloxane (Bifluid M, Bayer), methylphenylsiloxane (KF-54, Shin-Etsu Silicon), etc. can be obtained from the market and used.

  The addition amount of the diorganopolysiloxane is preferably 0.01 to 0.3% by mass with respect to the total amount of the contrast agent-containing tube molding material. If the addition amount is less than 0.01% by mass, the effect of improving the dispersibility cannot be obtained, and even if the addition amount exceeds 0.3% by mass, no further improvement in dispersibility is observed, which is uneconomical.

  In order to manufacture a tube containing a contrast agent, first, an X-ray contrast agent powder and, if necessary, a diorganopolysiloxane compound and a whitening inorganic filler powder are added to a heat-meltable fluororesin, Melt and mix at a temperature higher than the melting temperature of the meltable fluororesin. Each raw material can be mixed in advance using a mixer such as a Henschel mixer, a V-type mixer, or a double cone mixer before being melt-mixed. The melt mixing can be performed using, for example, a twin screw extruder.

  Next, for example, a pellet is produced by extrusion molding into a strand shape.

  The obtained pellets are supplied to an extrusion molding machine and extruded into a tube having a predetermined shape to obtain a contrast medium-containing tube. The obtained contrast agent-containing tube is free from aggregates derived from the X-ray contrast agent powder and the whitened inorganic filler powder, and has excellent durability and surface properties.

  Hereinafter, the present invention will be further described with reference to examples and comparative examples, but the present invention is not limited thereto.

(Examples 1 to 3 and Comparative Example 1)
Tetrafluoroethylene-ethylene copolymer resin ("Aflon COP C88AX" manufactured by Asahi Glass; labeled ETFE in Table 1) or tetrafluoroethylene-perfluoroalkoxyethylene copolymer resin (manufactured by Mitsui Dupont Fluorochemical) “440HP-J”; indicated as PFA in Table 1) was prepared. Further, bismuth oxide powder (“FP” manufactured by Nippon Kagaku Sangyo Co., Ltd.) as X-ray contrast agent powder is classified to 20 μm or less and dried at 110 ° C. for 12 hours, and barium sulfate powder (“B-1” manufactured by Sakai Chemical). Was prepared to be 20 μm or less and dried at 110 ° C. for 12 hours. In addition, titanium oxide (“A-171” manufactured by Sakai Chemical) was prepared as a whitening inorganic filler. For comparison, a bismuth oxide that was not classified and did not dry was prepared.

  Each of the above materials was put into a twin-screw extruder (cylinder diameter: 15 mm) at the ratio shown in Table 1, and 0.2% by mass of silicon oil (“KF-96” manufactured by Shin-Etsu Chemical Co., Ltd.) was added to each. Then, the mixture was melt-mixed at 280 ° C. when ETFE was used and 370 ° C. when PFA was used. Next, each mixture was extruded into a strand shape with a twin-screw extruder with a cylinder / extrusion head set at 285 ° C. to produce pellets. Each pellet was put into an extrusion molding machine and formed into a tube shape having an outer diameter of 2 mm and an inner diameter of 1 mm.

  The color tone and appearance defect of each obtained contrast agent-containing tube were visually evaluated, and further, a cross-sectional SEM photograph was taken to confirm the presence or absence of aggregates and to evaluate dispersibility. Regarding dispersibility, the case where large particles having a particle diameter of 20 μm or more were present in the tube wall was determined as “poor”, and the case where no particles were present was determined as “good”. As for the appearance defect, when there was unevenness on the surface, “Yes” was indicated, and when there was no unevenness, “No” was indicated. The results are also shown in Table 1.

  As shown in Table 1, according to the present invention, classified and dried X-ray contrast agent powder is used, and further by adding silicone oil, the dispersibility of the X-ray contrast agent powder is increased, and a contrast agent containing no aggregate is contained. It turns out that a tube is obtained.

It is a figure for demonstrating the malfunction in the conventional contrast agent containing tube, and is the SEM photograph which image | photographed the cross section.

Claims (5)

  A method for producing a tube containing a contrast medium containing an X-ray contrast medium in a tube wall, wherein the X-ray contrast medium powder classified to a particle size of 20 μm or less and dried is added to a heat-meltable fluororesin, and the heat melting A method for producing a contrast agent-containing tube, which comprises melt-mixing at a temperature equal to or higher than the melting temperature of the conductive fluororesin, pelletizing to produce pellets, and then forming the obtained pellets into a tube shape.   The heat-meltable fluororesin is selected from tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and tetrafluoroethylene-perfluoroalkoxyethylene copolymer. The method for producing a tube containing a contrast medium according to claim 1.   3. The method for producing a contrast agent-containing tube according to claim 1, wherein a diorganopolysiloxane compound is added.   The whitening inorganic filler powder is added, The manufacturing method of the contrast agent containing tube of any one of Claims 1-3 characterized by the above-mentioned.   The method for producing a tube containing a contrast agent according to claim 4, wherein the whitened inorganic filler powder is titanium oxide coated with aluminum oxide.