Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS3228894 A
Publication typeGrant
Publication dateJan 11, 1966
Filing dateDec 24, 1962
Priority dateDec 24, 1962
Publication numberUS 3228894 A, US 3228894A, US-A-3228894, US3228894 A, US3228894A
InventorsJeckel Norman C
Original AssigneeUs Catheter & Instr Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Fluorocarbon tungsten members
US 3228894 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

United States Patent C 3,228,894 FLUORQCARBON TUNGSTEN MEMBERS Norman C. Jeckel, Glens Falls, N.Y., assignor to United States Catheter 81 Instrument Corporation, Glens Falls, N.Y., a corporation of New York No Drawing. Filed Dec. 24, 1962, Ser. No. 246,684 Claims. (Cl. 252478) This invention relates to new and useful improvements in radiopaque fluorocarbon tubing and more particularly seeks to provide a cardiac catheter composed primarily of fluorocarbon and tungsten.

The unusual properties of the fiuorocarbons, particularly polytetrafiuoroethylene, are ideal for forming extruded tubing such as cardiac or other catheters because of the following properties, among others. First, within the temperature range of 70-110 F., there is no appreciable change in degree of stiffness. Second, the curved distal tips are heat set at over 600 F. and do not flatten out at body temperature, thus making introduction easier. Third, the lowest coeflicient of friction of any known materials makes them less traumatic and easier to introduce. Fourth, their non-wettable surfaces reduce the tendency of the catheter to coagulate blood. Fifth, their zero absorption of water as liquid or vapor causes catheters to retain their length and hardness longer than most other materials. Sixth, they are unaffected by temperature up to 600 F. and thus may be repeatedly boiled or autoclaved with no harmful effect. The autoclaving causes no softening and need not be followed by drying because no moisture can be absorbed as already pointed out. Seventh, nothing sticks to fluorocarbons, not even strong adhesives, and thus they are easy to clean and have much less tendency to collect deposits of any kind. Eighth, the lumen is extremely smooth and friction-free so as to be ideal for injections where the lowest possible resistance to flow is necessary. Ninth, the materials are non-toxic, inert and have a lower order of tissue reactivity.

It is essential in most instances for cardiac catheters to be radiopaque in order to follow the path of introduction on the fluoroscope. Accordingly, conventional radiopaque metals such as tin, lead and bismuth have been added to the fluorocarbons. However, the powdered polytetrafluoroethylene is extruded at room temperature but then sintered at 650-800 F., generally 750, whereupon these metals are discolored and thereafter deteriorate relatively rapidly so that the catheters tend to split, crack, etc., under pressure and mechanical distortion. Furthermore, these metals are medically toxic.

It is, therefore, an object of this invention to provide a radiopaque fluorocarbon tube which will not discolor during sintering, nor deteriorate thereafter and which will contain no medically toxic materials.

I have found that these objects may be attained by incorporating tungsten Within the fluorocarbon composition of cardiac catheters or other radiopaque members.

With the above objects and features in view, the nature of which will be more apparent, the invention will be more fully understood by reference to the accompanying detailed description and the appended claims.

To 80 parts by weight of polytetrafluoroethylene powder is intimately mixed 20 parts of tungsten powder and suflicient mineral spirits solvent to make a paste for extrusion. This is then extruded at room temperature into the desired cardiac catheter shape and subsequently sintered at about 750 F. to produce a non-toxic catheter 3,228,894 Patented Jan. 11, 1966 having excellent flex-resistance with no deterioration or discoloration.

It is obvious that in addition to cardiac catheters, any tubular, rod or other shape extrusion where radiopacity is desired may be formed. Extrusion may be from a melted liquid (FEP) or the extrusion and sintering may be a simultaneous operation starting with a dry mixture of materials if sufficient pressure and proper temperature is used. The sintering temperature will be that normal for polytetrafluoroethylene which presently ranges from 650-800 F. The invention is applicable to any of the fluorocarbons, e.g. polytetrafluoroethylene (TFE), fluorinated ethylene propylene (FEP), (both sold und r Du Ponts registered trademark, Teflon), polytrifluorochloroethylene (sold under Minnesota Mining and Manufacturing Companys trademark, EL-F), and other chlorinated fluorocarbons.

Since tungsten is very dense (specific gravity of 19.3), its relative volume in the composition will be much less than its relative weight. The range of tungsten by weight is preferably from 5 to 30% of the total composition. Amounts outside this range are usable but. the radiopacity is relatively weak below 5% and the mechanical properties of the fluorocarbon is weakened above 30%.

I claim:

1. A radiopaque material comprising a solid fluorocarbon polymer and sufficient tungsten intimately mixed therewith to render said material radiopaque.

2. A radiopaque extruded member comprising a solid fluorocarbon polymer and suflicient tungsten intimately mixed therewith to render said material radiopaque.

3. A radiopaque extruded and sintered tube member formed from a fluorocarbon polymer powder and 5 to 30% by weight of tungsten powder intimately mixed therewith.

4. The member of claim 3 wherein said tube is a cardiac catheter.

5. The member of claim 4 wherein said fluorocarbon is polytetrafluoroethylene.

6. The member of claim 4 having about 20% of said tungsten.

7. A method for forming a radiopaque tube comprising intimately mixing fluorocarbon polymer powder and sufiicient tungsten powder to render said tube radiopaque, extruding said mixed powder as said tube, and sintering said extruded tube at about 650800 F.

8. The method of claim 7 wherein said tungsten comprises 5 to 30% by weight of the total powder content.

9. The method of claim 8 wherein said fluorocarbon is polytetrafluoroethylene.

10. The method of claim 9 wherein said tungsten is about 20% References Cited by the Examiner UNITED STATES PATENTS 2,230,654 2/ 1941 Plunkett 260-33.8 2,644,804 7/1953 Rubin 260-33.8 2,752,637 7/1956 Walker et al. 264-119 2,857,915 10/1956 Sheridan 128349 2,985,918 5/1961 Moore et al 260-338 3,075,925 1/1963 Dunegan 252478 3,089,866 5/1963 Crawford 26087.5 X 3,094,585 6/ 1963 Rudner 264-127 X CARL D. QUARFORTH, Primary Examiner.


Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2230654 *Jul 1, 1939Feb 4, 1941Kinetic Chemicals IncTetrafluoroethylene polymers
US2644804 *Apr 22, 1950Jul 7, 1953Kellogg M W CoPacking composition containing polytrifluorochloroe thylene and an inorganic antifriction agent
US2752637 *Jul 1, 1954Jul 3, 1956Resistoflex CorpExtrusion of polytetrafluoroethylene
US2857915 *Apr 2, 1956Oct 28, 1958Sheridan David SX-ray catheter
US2985918 *Jan 20, 1959May 30, 1961Raybestos Manhattan IncMethod for forming shaped lengths of tetrafluoroethylene polymers having a cellular structure
US3075925 *Dec 21, 1960Jan 29, 1963Harold L DuneganRadiation shielding composition
US3089866 *May 25, 1956May 14, 1963Minnesota Mining & MfgProcess for the preparation of fluorine-containing polymers
US3094585 *Apr 16, 1951Jun 18, 1963Garlock IncFluorocarbon resin mixtures and metal to plastic bonding
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3608555 *Dec 31, 1968Sep 28, 1971Chemplast IncRadio opaque and optically transparent tubing
US3612038 *Feb 3, 1969Oct 12, 1971Becton Dickinson CoPreformable catheter package assembly and method of preforming
US3815608 *Mar 10, 1972Jun 11, 1974East West Med ProdRetaining catheter
US3818229 *Dec 21, 1970Jun 18, 1974Univ IllinoisRadiopaque agents comprising brominated perfluorocarbons
US3829903 *Mar 15, 1973Aug 20, 1974Dow CorningMethod of inhibiting blood clot on silicone rubber medical devices
US4182342 *Apr 28, 1978Jan 8, 1980Med-Pro, Ltd.Naso-gastric feeding device and method of inserting same
US4247510 *Dec 10, 1979Jan 27, 1981CefilacProcess for depositing an elastomeric or thermosetting bank on a support
US4469483 *Aug 25, 1982Sep 4, 1984Baxter Travenol Laboratories, Inc.Radiopaque catheter
US5147318 *Mar 4, 1991Sep 15, 1992Board Of Regents, The University Of Texas SystemValved arterial catheter
US5336205 *Feb 25, 1993Aug 9, 1994Target Therapeutics, Inc.Flow directed catheter
US5538512 *Jul 8, 1994Jul 23, 1996Zenzon; Wendy J.Lubricious flow directed catheter
US5730733 *May 31, 1996Mar 24, 1998Scimed Life Systems, Inc.Flow assisted catheter
US5899892 *Nov 7, 1997May 4, 1999Scimed Life Systems, Inc.Catheter having distal fiber braid
US5947939 *Mar 14, 1997Sep 7, 1999Scimed Life Systems, Inc.Flow assisted catheter
US5961511 *Oct 28, 1998Oct 5, 1999Scimed Life Systems, Inc.Catheter having LCP reinforced distal portion
US6193705Sep 3, 1999Feb 27, 2001Scimed Life Systems, Inc.Flow assisted catheter
US7704245Apr 13, 2004Apr 27, 2010Cook IncorporatedLarge diameter delivery catheter/sheath
US7968038Mar 8, 2010Jun 28, 2011Cook Medical Technologies LlcLarge diameter delivery catheter/sheath
US20040220549 *Apr 13, 2004Nov 4, 2004Dittman Jay A.Large diameter delivery catheter/sheath
US20050090802 *Apr 26, 2004Apr 28, 2005Connors John J.IiiFlexible sheath with varying durometer
US20100163159 *Mar 8, 2010Jul 1, 2010Cook IncorporatedLarge diameter delivery catheter/sheath
DE1965487A1 *Dec 30, 1969Nov 19, 1970Chemplast IncKatheter und Verfahren zu seiner Herstellung
EP2561898A1Aug 24, 2012Feb 27, 2013Cook Medical Technologies LLCMedical balloon and balloon catheter assembly
WO1992015352A1 *Mar 4, 1992Sep 17, 1992Board Of Regents, The University Of Texas SystemValved arterial catheter
U.S. Classification252/478, 604/529, 264/127, 138/118, 524/440, 524/546, 523/112
International ClassificationA61M25/01
Cooperative ClassificationA61M25/0108
European ClassificationA61M25/01C1