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.

Patents

  1. Advanced Patent Search
Publication numberUS2637321 A
Publication typeGrant
Publication dateMay 5, 1953
Filing dateSep 27, 1951
Priority dateMar 20, 1944
Publication numberUS 2637321 A, US 2637321A, US-A-2637321, US2637321 A, US2637321A
InventorsArthur Cresswell
Original AssigneeAmerican Cyanamid Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Shaped article and method of producing it
US 2637321 A
Abstract  available in
Images(3)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

Patented May 5, 1953 SHAFEB `RIICILII AND METHGD 0F PRODUCING IT Arthur. vCressrwell, Stamford, Conn., assigner'.l tov American @yann-mid Company, New YorlsN.- Y., a corporation of Maine NoD'rawing.; Application' September 27', 195.1,

Serial No. 248,671

(Cl. 12S-335.5)

13 Claims. l

The present invention 'relatesto" iilamients, threads, strands :and tapes, hereinafter sometimes referred toas shapes or strands "The inven tion-further relates to suchfsliaped articles' oonsisting 'essentially or regenerated'collagenand to methods otiprodu'cing them..

The invention is: particularly. oonoerned with themanuiaoture: ortsuch: strands from collagen orlcolla'gienous rriaterial.A

The shapes' pro'duc'edhyftlie present .invention are particularly"usefurastsurgical .sutures or' lign tures' and have decided advantage over. thor articles normally produced from` intestinal rnaterial known astoatguhf. The present collagenous shapes'maybe pro duced in unlimited lang lhs, are uniform;` throughout their length: to. size, strength,. toughnesslifand. capacity for indirect or heat sterilization. Any desired degree of :tannage may be given such suturesV or: ligatures. in the usual` variety oi tanning baths.

Collagen isa protein which is. an. ingredient of the hide, skin, `iasoialata-.andirnisoles of vertebrates and occurs; therein aslbrous matter, along with a multitudefof. other substances such as hair,

elastin .and other insolublesiromlwhioli ool'- lagen must Ibe separatedbeforeitoan bei suocessfully used according to: theapresent invention.

Collagen yis. itself insoluti-le.- in water butit may, upon suitable. treatment in water: and,` at' an elevated temperature, be converted to' gelatin. Whilegelatin and collagen are both protein, yet they are dissimilar and are not equivalents. Itis well know that gelatin is soluble in water which 'Ls not true of collagen.

lThrov gliout4 the: present` speeific'ation and claims, Where' the words'collagen` or Collageh nous materia are used, it to oe understoodthat the material thereby designated is to be oompletelyA differentiated from gelatin as thetwomaterials are not at all interchangeable in 'carrying out the purposes of the invention'.

Broaolly speaking, the invention contemplates theextrusion of a collagen solution through a smallorince iollowedhy coagulation of the extruded filament. Such' threads may be made oi any desired sizeor shape and' either ooagulated or coller-ed in such shape or spun, twisted or woven together in multi-filament forni iorlarger threads or'shapes. Such strands and tapes, dueto their manner of manufacture, may be produced in unlimited lengths, the dimensions of which are re.- markably uniform throughout their length.

Such strands may be tanned lay the usual methods employed intlietannage of leather, and sutures prepared' therefrom may' be made in vary- Adesirable in using this source of material thatunlimed hicles'lie chosen. These may be fresh-or green-salted cali slin, kip skin or other' hides which are comparatively lov! inl elastin content. Kip shin is preferred because thel collagen therefrom is of optiinurnl viscosity as compared to that of call-f'sliin. These' are fleshed andi unhairfed down to the clean corium which isv that lamination of the animal hide containing' the greatest proportion of collagen. If green-salted tides' are used, the hides should he soaked heiore this treatment also allowed to remain` in the soaking liquid after cleaning until substantially salt free.

After cutting the ooriuin into strips or small piecesior convenience in' handling, the ooriuin is covered with a dilute solution of an organic acid preferably, though not necessarily; in the pli range of from 2 to Any organic' acid is satisfaotory although from 0.0515@ 0.1.6 N orinie aoid or 0.5 to 1.0 N acetic acid arepreierred. Any other: concentration of otherr organic acids naar,r be' used;

The corium is thus allowed` to' swell for' from sixteen to twenty-'four hours' in the acid. solution at temperatures between' l0 and 30 C'. In, this swelling, the hide lmhioes from oneito three times itsownweiglit of liquid butby maintaining the temperature at this point Ibelow 30 C., gelatin forming conditions are definitely avoided.`

Fol-lowing the swelling, the excess liquid is drained oli and tlieswollen oorium mechanically disintegrated, for example, oy a meat grinder, shredder or other 'form oi sub1-dividing mechanism which Will break down the'collagenfibers to the point where dissolution will he facilitated. In the mechanical disintegration step, heat may be developed dueto friction andA it is, therefore, iin;- portant that the necessary steps bev taken to maintain the material during this operation; at temperatures below 30o C.

At this stage andii the mechanical disintegration haslheen line enough, practically' all of` the collagen will have gone into solution.y Where this collagen solution is highly concentrated, it will gel at 35 C. or. below. Therefore, to separate the dissolved. collagen from the insolubles,l it may loe desirable` tol warm it slightly until fluidity has been reached. Thisk will. certainly `be, at a. tem.- perarture no higher than C.,` While warming to this temperature, if mechanical agitation. is carried on, any last traoesofundissolved collagen will dissolve and the Wholeniay then be centri'- fuged and ltered to remove fibers, elastin, hair fragments and other insoluble matter. The filtrate will be a clear heavily concentrated solution of collagen.

While the preferred source of collagen is the corium as this involves handling a material of maximum collagen content with minimum insolubles, yet as a matter of fact, due to the distribution of collagen throughout the animal hide, it may be desirable to disintegrate vthe entire hide followed by collagen solution in dilute organic acid and the separation of the insolubles. Such a process while varying inthe last step in the removal of an excessive amount of insolubles, does extract substantially all the collagen available.

The concentration of the collagen in its solution may be adjusted to a desired content appropriate for spinning by the addition of a further amount of the dilute organic acid solution such as that used for swelling and solution. It is pre- 'ferred that the spinning solution contain from 5 to collagen although solutions of lower or higher collagen concentration may be used.

Before spinning, it is desirable to deaerate in order that there may be no thread interruption due to the passage of air bubbles through the jet orice. Therefore, by maintaining the collagen solution at a temperature slightly above that at which it will gel and applying a vacuum or partial Vacuum, the air contained in the solution may be removed. The warm solution may then be pumped by any suitable means to a spinnerette, that used in the rayon industry for this purpose being eminently satisfactory, and then immersed in a coagulating bath.

This type of extrusion, that is, from' solution, is to be distinguished from the method such as 'extrusion of a pulp of swollen collagen, not in solution and skin containing insolubles. Such a method is distinctly disadvantageous as large sized orices are required and the filaments resulting therefrom are non-uniform as to size, strength and the like due to the non-uniformity of collagen content.

Strong salt solutions have been found satisfactory as coagulating baths, su-ch as a 35% to saturated solution of ammonium sulfate with sufiicient free ammonia to maintain a pH of 7.8, which is an isoelectric point of collagen. The free ammonia is useful for the purpose of neutralizing the organic acid introduced by the spinning solution, Another satisfactory bath is one containing by weight of magnesium sulfate, buffered with triethanolarnine to a pH of 7.8. Regardless of the particular coagulant used, it

is highly desirable that the bath be maintained at from 20 to 30 C.

It has been found that collagen solutions of the concentrations above mentioned may be extruded into a coagulating bath as above described from spinnerettes with orifices of from' 50 microns to 1 mm., but preferably from 75 to 250 microns in diameter. The lament or thread may be passed over a plurality of revolving wheels commonly called godets which have in-creasing peripheral speeds so that a stretch is imparted to the lament or thread. Following this, the filament or thread may be taken up by a revolving spool which may or may not impart a further stretch. Satisfactory filaments have been spun as above from a spinnerette with orices measuring 110 microns in diameter to a iinished filament at the rate of 80 meters a minute. At this rate, the jetted material remains in contact with the coagulating bath for less than one second.

Adhering coagulants may then be washed from the lament or thread by passing the same in contact with water at a temperature below that at which softening will occur such as less than 20 C. The washed lament or thread may then be dried in air heated to from room temperature to 60 C. However, the lower the temperature the less damage may occur to the treated material.

Where a multi-filament strand is desired, a multi-hole spinnerette may be used. When spinning onto spools, the resulting strand is washed, dried and then twisted. It is also possible to twist the strand while spinning by collecting the strand in a centrifugal pot as commonly practiced in Viscose rayon pot spinning.

Single or multi-lament strands may be tanned in baths commonly used ior the tannage of surgical sutures from gut to determine the degree of body absorption which would be characteristic of the nished article.

It has been noted that when the wet iilaments from' the -coagulating bath are twisted together to form a strand and permitted to remain in contact with each other without drying, a coalescence or cohesive action occurs which tends to make a unitary strand out of the laments. Thus, if a large single coherent strand is desired to be made from a number of smaller filaments, it is only necessary to spin the desired number of lilaments with the coagulating bath, arrange them in contact with each other and keep them wet until coalescence occurs. Thus any size or shape of strand er tape may be secured.

By using suitable godets, any desirable degree of stretch may be imparted to the spin nlaments. Oi course, the degree of stretch will determine in large measure the degree of fiber orientation in the nished lament, thread or strand. Reasonably satisfactory orientation has been obtained through stretching a lament to an extent equal to 700% by using a combination of godets having increasing peripheral speeds.

This application is a continuation-in-part of copending application Serial No. 527,339, iiled March 20, 1944, now abandoned.

While the invention has been described with particular reference to specic embodiments, it is to be -understood that it is not to be limited thereto but is to be construed broadly and restricted solely by the scope of the appended claims.

I claim:

1. A shaped article consisting essentially of regenerated collagen free from nbers and any other material insoluble in a dilute aqueous solution of an organic acid.

2. A shaped article consisting essentially of regenerated collagen free from bers and any other material insoluble in a dilute aqueous solzuttioqn of an organic acid in the range of pH 3. A shaped article consisting essentially of coalesced filaments of regenerated collagen free from bers and any other material insoluble in a dilute aqueous solution of an organic acid.

fi. A method of making a regenerated collagenous shape which includes the steps of dissolving collagen from collagenous material in a dilute aqueous solution of an organic acid removing all insolubles including bers from said solution While maintaining the temperature of said solution above its gelling point but below a temperature at which substantial conversion to gelatin occurs, extruding the thus heated solution into a -coagulating bath and removing the coagulated shape therefrom.

5. The method of claim 4 in which the concentration of collagen in the extrusion solution is from 5% to 15%.

6. A method of matting a regenerated collagenous shape which includes dissolving collagen from collagenous material by soaking and swelling said collagenous material in an aqueous solution of an organic acid at a pH of substantially 2-4, mechanically disintegrating said swollen coalageous material in said dilute aqueous solution of an organic acid, removing all insolubles including fibers from said solution while maintaining the temperature of said solution above its gelling point but below a temperature at which substantial conversion to gelatin occurs, extruding the thus heated solution into a, coagulating bath and removing the ooagulated shape therefrom.

7. The method of claim 6 in which the coagulated shape is stretched after extrusion to 700%.

8. The method of claim 6 in which the collagenous material is animal corium.

9. The method of claim 6 in which the collagenous material is corium from kip skin.

10. A method of making a regenerated collagenous strand Which includes dissolving collagen from collagenous material by soaking and swelling said collagenous material in `an aqueous solution of an organic acid 'at `a pli of substan" tially 2-4, mechanically disintegrating said swollen collagenous material 'in said aqueous solution of an organic acid, removing all insolubles including iibers from said solution While maintaining the temperature of said solution in the range oi substantially 35-59 C., eXtruding the thus heated solution into a coagulating bath and removing the coagulated strand therefrom.

11. The method of claim 10 in which the collagen solution is deaerated before spinning.

12. A method of making a collagen multi-lament suture strand which comprises extruding a :liber-free, Iaqueous organic acid solution Vof collagen maintained at a temperature above its gelling point but below a tempera-ture at which substantial conversion to gelatin occurs, through a multi-holed spinnerette into a coagulating bath, removing the thus spun filaments from the bath and Washing and drying said laments While held apart from each other and then twisting the filaments into a strand..

13. The method of claim 12 in Which the collagen solution is dissolved in an aqueous organic acid solution having a pli of substantially 2-4, the concentration of collagen being 5-15% `and the `solution being deaerated before spinning.

ARTHUR CRESSWELL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,949,111 Randall Feb. 27, 1934 2,039,262 Schulte Apr. 28, 1936 2,126,344 Pierson Aug. 9, 1938 2,120,851 Becker et al June 14, 1938 2,475,697 CressWell July 12, 1949 2,476,293 Hall et al July 19, 1949 2,485,958 Cresswell Oct. 25, 1949 2,517,694 Merion et al Aug. 8, 1950 OTHER REFERENCES Publication: Kolloid-Zeitschrift Band 101,

Heft 2 (1942), Dn. 149-156. Article by Von A. V. Buzagh Uber die Bedingungen der Entstehung kunsthicher Kollagenfasern.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1949111 *Jul 7, 1930Feb 27, 1934Plastic Products IncSurgical suture
US2039262 *Feb 7, 1934Apr 28, 1936Koninklijke Pharma Fab NvProcess for the manufacture of threads, strings, bands, films, and the like
US2120851 *Sep 9, 1935Jun 14, 1938Freudenberg Carl GmbhProcess for the manufacture of spun goods, fabrics, and other textiles
US2126344 *Nov 30, 1936Aug 9, 1938Nat Products CorpPlastic material
US2475697 *Apr 19, 1946Jul 12, 1949American Cyanamid CoTreatment of collagen strands
US2476293 *Oct 3, 1944Jul 19, 1949American Viscose CorpArtificial fiber
US2485958 *Jul 25, 1946Oct 25, 1949American Cyanamid CoMethod of spinning collagen filaments
US2517694 *Sep 14, 1943Aug 8, 1950American Viscose CorpCrimped artificial filament
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3098696 *Aug 18, 1959Jul 23, 1963American Cyanamid CoManufacture of sterile surgical suture collagen
US3114591 *Apr 12, 1961Dec 17, 1963Ethicon IncProcess for the manufacture of suture material from animal tendons
US3272204 *Sep 22, 1965Sep 13, 1966Ethicon IncAbsorbable collagen prosthetic implant with non-absorbable reinforcing strands
US3284557 *Dec 20, 1962Nov 8, 1966Ethicon IncProcess for crimping an artificial implant for use in an animal body
US3316557 *Feb 15, 1965May 2, 1967Meadox Medicals IncSurgical, vascular prosthesis formed of composite yarns containing both synthetic and animal derivative strands
US3451394 *Apr 4, 1961Jun 24, 1969Ethicon IncRadiating tanned and untanned collagen prosthesis with 5 to 25 megarads of ionizing radiation
US3469003 *Apr 1, 1966Sep 23, 1969Haver Lockhart Lab IncInjectable reconstituted collagen fluid adjuvant for vaccines and other drugs
US3620775 *Aug 12, 1968Nov 16, 1971Tee Pak IncEdible collagen casing
US3653928 *Jun 30, 1969Apr 4, 1972Tee Pak IncEasily peeled synthetic casing
US5256418 *Apr 6, 1990Oct 26, 1993Organogenesis, Inc.Collagen constructs
US5316942 *Jun 16, 1993May 31, 1994Battelle Memorial InstituteProcess for the production of low-cost soluble high-molecular weight collagen
US5562946 *Nov 2, 1994Oct 8, 1996Tissue Engineering, Inc.Apparatus and method for spinning and processing collagen fiber
US5647957 *Jun 7, 1995Jul 15, 1997Ranpak CorporationMethod of preparing paper strengthened with solubilized collagen
US5686262 *Jun 7, 1995Nov 11, 1997Ranpak CorporationRecycle process for the production of low-cost soluble collagen
US5700353 *Jun 7, 1995Dec 23, 1997Ranpak CorporationPaper strengthened with solubilized collagen and method
US5700354 *Jun 7, 1995Dec 23, 1997Ranpak Corp.Paper strengthened with solubilized collagen and method
US5707491 *Jun 7, 1995Jan 13, 1998Ranpak CorporationPaper strengthened with solubilized collagen and method
US5711853 *Jun 7, 1995Jan 27, 1998Ranpak Corp.Paper strengthened with solubilized collagen and method
US5714042 *Jun 7, 1995Feb 3, 1998Ranpak CorporationPaper strengthened with solubilized collagen and method
US5736010 *Jun 7, 1995Apr 7, 1998Ranpak CorporationPaper strengthened with solubilized collagen and method
US5744002 *Jun 7, 1995Apr 28, 1998Ranpak Corp.Paper strengthened with solubilized collagen and method
US5810970 *Jun 7, 1995Sep 22, 1998Ranpak CorporationPaper strengthened with solubilized collagen and method
US5851290 *May 22, 1996Dec 22, 1998Tissue Engineering, Inc.Apparatus for spinning and processing collagen fiber
US5891167 *Jun 19, 1996Apr 6, 1999United States Surgical CorporationCollagen coated gut suture
US5911942 *Nov 2, 1995Jun 15, 1999Tissue Engineering, Inc.Method for spinning and processing collagen fiber
US5954748 *Jul 15, 1996Sep 21, 1999United States Surgical CorporationGelatin coated gut suture
US6361551Dec 11, 1998Mar 26, 2002C. R. Bard, Inc.Collagen hemostatic fibers
US6454787Dec 11, 1998Sep 24, 2002C. R. Bard, Inc.Collagen hemostatic foam
US8535591 *Nov 2, 2007Sep 17, 2013Green Materials, LlcProcess for preparing biodegradable articles
US20080105998 *Nov 2, 2007May 8, 2008R&D Green Materials, LlcProcess for Preparing Biodegradable Articles
EP0607346A1 *Oct 7, 1992Jul 27, 1994Organogenesis Inc.Collagen constructs
EP0607346A4 *Oct 7, 1992May 10, 1995Organogenesis IncCollagen constructs.
WO1995025550A1 *Mar 20, 1995Sep 28, 1995Organogenesis Inc.Biocompatible prosthetic devices
WO1996014452A1 *Nov 2, 1995May 17, 1996Tissue Engineering, Inc.Apparatus and method for spinning and processing collagen fiber
WO2001066835A1 *Mar 5, 2001Sep 13, 2001Tei Biosciences, Inc.Method and apparatus for biopolymer coagulation in a uniform flow
Classifications
U.S. Classification606/229, 264/102, 530/356, 264/202, 106/38, 264/103
International ClassificationA61L17/00, D01F4/00, A61L17/08
Cooperative ClassificationA61L17/08, D01F4/00
European ClassificationA61L17/08, D01F4/00