Sterilizable multilayer material

Abstract

Sterilizable multilayer material (1), in particular for packaging at least one device for medical use, comprising a non-thermofusible sheet (2) sandwiched between two lower and upper thicknesses (3, 4) of thermofusible material of at least one thermofusible sheet (F), these thicknesses of thermofusible material being welded together across the non-thermofusible sheet.

Claims

1. A sterilizable multilayer material, comprising a non-thermofusible sheet sandwiched between two lower and upper thicknesses of thermofusible material of at least one thermofusible sheet, these thicknesses of thermofusible material being welded together through the non-thermofusible sheet, an upper face of the non-thermofusible sheet being only partly covered by the upper thickness of thermofusible material, a lower face of the non-thermofusible sheet being totally covered by the lower thickness of thermofusible material, the thicknesses of thermofusible material together being defined by a single thermofusible sheet, the thermofusible sheet being chosen from among nonwoven materials consolidated by a wet process, by a dry process, or by a melt process.

2. The material as claimed in claim 1, the thermofusible sheet being defined by a sheet of nonwoven material consolidated by a melt process.

3. The multilayer material as claimed in claim 1, the non-thermofusible sheet being chosen from among nonwoven materials and papers.

4. The multilayer material as claimed in claim 1, the non-thermofusible sheet having two edges, the welding being done at least along at least part of at least one of said edges of the non-thermofusible sheet.

5. The multilayer material as claimed in claim 1, the non-thermofusible sheet having two edges, the thermofusible sheet being folded over on either side of the non-thermofusible sheet along its said edges and welded along at least part of said edges.

6. The multilayer material as claimed in claim 1, the welding being done along one or more welding lines, the welding being continuous or discontinuous along each welding line.

7. The multilayer material as claimed in claim 1, the multilayer material being devoid of adhesive between the assembled layers.

8. The multilayer material as claimed in claim 1, wherein the thicknesses of the thermofusible material extend along an outer edge of the non-thermofusible sheet and inwardly from said outer edge in order to only partly cover at least one major face of the non-thermofusible sheet with said at least one major face also being at least partly exposed.

9. The multilayer material as claimed in claim 1, the non-thermofusible sheet comprising cellulose fibers.

10. A method of fabrication of a multilayer material as claimed in claim 1, involving a step in which the upper thickness of thermofusible material is welded to the lower thickness of thermofusible material through the non-thermofusible sheet.

11. The method as claimed in claim 10, wherein the welding is done by ultrasound.

12. The method as claimed in claim 10, wherein the welding is done by conduction, laser or hot gas.

13. The method of fabrication as claimed in claim 10, wherein the lower thickness of thermofusible material and the upper thickness of thermofusible material are defined by the same thermofusible sheet, the method involving a step prior to the welding step, in which the thermofusible sheet is folded over onto itself so as to grasp the non-thermofusible sheet in sandwich fashion.

14. The method as claimed in claim 10, the non-thermofusible sheet not undergoing a microperforation prior to the welding in the zone where the lower and upper thicknesses of thermofusible material are overlapping.

15. The method as claimed in claim 10, wherein the non-thermofusible sheet undergoes a microperforation step prior to the welding in the zone where the lower and upper thicknesses of thermofusible material are overlapping.

16. A combination of a multilayer material as claimed in claim 1 and at least one device for medical use, wrapped in said material in a sterile condition.

17. An operative field comprising a multilayer material as claimed in claim 1.

18. A sterilizable multilayer material, comprising a non-thermofusible sheet sandwiched between two lower and upper thicknesses of thermofusible material of at least one thermofusible sheet, these thicknesses of thermofusible material being welded together through the non-thermofusible sheet, an upper face of the non-thermofusible sheet being only partly covered by the upper thickness of thermofusible material, a lower face of the non-thermofusible sheet being totally covered by the lower thickness of thermofusible material, the thicknesses of thermofusible material together being defined by a single thermofusible sheet, the multilayer material having a sealing strength, as claimed in the standard ASTM F88, greater than or equal to 100 cN/15 mm.

19. A sterilizable multilayer material, comprising a non-thermofusible sheet sandwiched between two lower and upper thicknesses of thermofusible material of at least one thermofusible sheet, these thicknesses of thermofusible material being welded together through the non-thermofusible sheet, an upper face of the non-thermofusible sheet being only partly covered by the upper thickness of thermofusible material, a lower face of the non-thermofusible sheet being totally covered by the lower thickness of thermofusible material, the thicknesses of thermofusible material together being defined by a single thermofusible sheet, the multilayer material comprising a supplemental upper non-thermofusible sheet, having an upper face and a lower face, the upper thickness of thermofusible material being partly or totally covered by the lower face of the supplemental upper non-thermofusible sheet, the upper face of the supplemental upper non-thermofusible sheet being partly or totally covered by an upper thickness of thermofusible material of second rank, the upper thickness of thermofusible material and the upper thickness of thermofusible material of second rank being welded together across the supplemental upper non-thermofusible sheet.

20. A sterilizable multilayer material, comprising a non-thermofusible sheet sandwiched between two lower and upper thicknesses of thermofusible material of at least one thermofusible sheet, these thicknesses of thermofusible material being welded together through the non-thermofusible sheet, an upper face of the non-thermofusible sheet being only partly covered by the upper thickness of thermofusible material, a lower face of the non-thermofusible sheet being totally covered by the lower thickness of thermofusible material, the thicknesses of thermofusible material together being defined by a single thermofusible sheet, the multilayer material comprising a supplemental non-thermofusible sheet, having an upper face and a lower face, the lower thickness of thermofusible material being partly or totally covered by the upper face of a supplemental lower non-thermofusible sheet, the lower face of the supplemental lower non-thermofusible sheet being partly or totally covered by a lower thickness of thermofusible material of second rank, the lower thickness of thermofusible material and the lower thickness of thermofusible material of second rank being welded together across the supplemental lower non-thermofusible sheet.

21. A sterilizable multilayer material, comprising a non-thermofusible sheet sandwiched between two lower and upper thicknesses of thermofusible material of at least one thermofusible sheet, these thicknesses of thermofusible material being welded together through the non-thermofusible sheet, an upper face of the non-thermofusible sheet being only partly covered by the upper thickness of thermofusible material, a lower face of the non-thermofusible sheet being totally covered by the lower thickness of thermofusible material, the thicknesses of thermofusible material together being defined by a single thermofusible sheet, wherein the non-thermofusible sheet includes perforations therethrough, allowing the thicknesses of thermofusible material to be welded together through the non-thermofusible sheet.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention may be better understood upon perusal of the following detailed description of nonlimiting sample embodiments and an examination of the appended drawing, in which:

(2) FIG. 1 shows, in cross section and schematically, an example of multilayer material according to the invention,

(3) FIGS. 2 to 10 show, in cross section and schematically, variant examples of multilayer material according to the invention,

(4) FIG. 11 illustrates, in top view, part of the multilayer material of FIG. 1,

(5) FIG. 12 represents the part of the multilayer material of the preceding figure on which is arranged, in schematic manner, part of a medical device ready to be packaged.

DESCRIPTION OF EXAMPLE EMBODIMENTS

(6) In FIGS. 1 to 10, the different component parts have been shown schematically before assembly. The real proportions are not always obeyed, for reasons of clarity.

(7) FIG. 1 shows a multilayer material 1 for the packaging of at least one device for medical use according to the invention.

(8) The material comprises a non-thermofusible sheet 2 having a lower face S.sub.inf-p and an upper face S.sub.sup-p. This non-thermofusible sheet is preferably a nonwoven material or a cellulosic paper, as detailed above.

(9) The lower face S.sub.inf-p is covered by a lower thickness of thermofusible material 3, and the upper face S.sub.sup-p is covered by an upper thickness of thermofusible material 4.

(10) The lower thickness of thermofusible material and the upper thickness of thermofusible material are formed here by the same thermofusible sheet F, in contact with the non-thermofusible sheet 2.

(11) The thermofusible sheet F thus covers entirely the lower face S.sub.inf-p of the non-thermofusible sheet 2 and partly its upper face S.sub.sup-p.

(12) The thermofusible sheet F is folded over on either side of the non-thermofusible sheet 2, and holds it in sandwich fashion.

(13) The non-thermofusible sheet 2 has two parallel edges 5a and 5b, along which the sheet F is folded.

(14) The sheet F is welded to itself along the two edges 5a and 5b of the sheet 2, along two welding lines 6a and 6b, across the sheet 2. In the area of the welding, the multilayer material thus contains three thicknesses one on top of the other.

(15) One may thus seal a thermofusible sheet F comprising a thermoplastic compound, especially one of type SMS, to a non-thermofusible cellulosic sheet 2, despite their incompatibility for direct welding. This is made possible thanks to the sandwiching of the non-thermofusible sheet by the sheet F, the latter being folded over in the manner of a hem.

(16) In order to weld the sheet F to itself across the sheet 2, one positions the sheet 2 on the sheet F. This latter has a width greater than that of the sheet 2, so that it can be folded over along the edges of the latter and grasp it in sandwich fashion.

(17) The upper and lower portions of the sheet F can thus be welded together at an ultrasound welding station.

(18) FIG. 7 illustrates a variant of the material according to the invention, wherein the sheet F is folded over and welded solely along one edge of the sheet 2.

(19) In the example of FIG. 8, the multilayer material 1 comprises a supplemental non-thermofusible sheet 2′ covering the sheet 2 and being grasped in sandwich fashion with it, along its edge 5′a, by the sheet F welded to itself along a welding line 6a.

(20) The multilayer material 1 likewise comprises a second thermofusible sheet F′, which grasps in sandwich fashion the sheet 2 and the supplemental sheet 2′, along their respective edges 5b and 5′b, the portions placed one on top of the other being welded along a welding line 6b.

(21) Thus, the sheet 2 and the supplemental sheet 2′ are secured at their edges by the sheets F and F′. This makes it possible to assemble two non-thermofusible sheets 2 and 2′ without adding adhesive.

(22) The multilayer material of FIG. 8 is lacking in the second sheet F′ in one embodiment not shown.

(23) FIG. 6 illustrates an example of multilayer material 1 according to the invention in which the lower thickness of thermofusible material 3 and the upper thickness of thermofusible material 4 come from the same sheet F folded on either side of the sheet 2, covering entirely the upper face S.sub.sup-p and lower face S.sub.inf-p of the sheet 2. The welding 6 is done along one edge 5 of the sheet 2, on the side opposite the folding of the sheet F.

(24) FIGS. 2 to 5 illustrate variants of the multilayer material 1 according to the invention, in which the lower thickness of thermofusible material 3 and the upper thickness of thermofusible material 4 are formed from distinct thermofusible sheets.

(25) FIGS. 2 to 4 illustrate a multilayer material 1 in which the upper thickness of thermofusible material 4 partly covers the sheet 2.

(26) In the example of FIG. 2, the welding 6 is done along an edge 5 of the sheet 2. In the example of FIG. 3, it is done substantially in the center of the sheet 2.

(27) In the example of FIG. 4, the multilayer material comprises a second upper thermofusible sheet 4′. The welding 6 is done along the two edges 5a and 5b of the sheet 2, between the upper thickness of thermofusible material 4 and the lower thickness of thermofusible material 3 on the one hand, and between the second upper sheet 4′ and the lower thickness of thermofusible material 3 on the other hand.

(28) In the example of FIG. 5, the upper thickness of thermofusible material 4 entirely covers the sheet 2 and the welding is done along opposite edges 5a and 5b of the sheet 2.

(29) FIG. 9 shows an example of multilayer material 1 comprising a sheet 2 and a sheet F as previously described in reference to FIG. 1.

(30) The multilayer material 1 furthermore comprises a supplemental upper non-thermofusible sheet 10, and a supplemental upper thermofusible sheet of second rank 11.

(31) The multilayer material 1 has welds 6c, 6d of the sheet F to the upper sheet of second rank 11 across the upper non-thermofusible sheet 10, situated on top of the welds 6a, 6b of the sheet F to itself across the sheet 2.

(32) FIG. 10 illustrates an example of multilayer material 1 comprising a non-thermofusible sheet 2, an upper thermofusible sheet 4 and a lower thermofusible sheet 3 as described previously in reference to FIG. 5.

(33) The multilayer material 1 furthermore comprises a supplemental lower non-thermofusible sheet 20, and a supplemental lower thermofusible sheet of second rank 21.

(34) The multilayer material 1 has welds 6e, 6f of the lower sheet 3 to the lower sheet of second rank 21 across the lower sheet 20. These welds 6e, 6f are not situated on top of the welds 6a, 6b of the upper sheet 4 to the lower sheet 3 across the sheet 2.

(35) The outermost sheets 4 and 21 of the multilayer material 1 are thermofusible.

(36) FIGS. 11 and 12 show in top view a portion of the multilayer material 1 of FIG. 1. FIG. 12 also shows a medical device 30 to be packaged, placed on the upper face S.sub.sup-p of the non-thermofusible sheet 2. The welding 6a along the edge 5a of the sheet 2 is in the form of a discontinuous welding line.

(37) Of course, the invention is not limited to the examples illustrated and in particular one can combine the characteristics of the examples illustrated within variants which have not been illustrated.

(38) The term “comprising a” should be understood as being synonymous with “comprising at least one”, unless otherwise stipulated.