Magnetic sheet assembly for magnetic separation

• US 20020084880A1
• Filed: 10/11/2001
• Published: 07/04/2002
• Est. Priority Date: 11/27/2000
• Status: Active Grant

• Current Assignee: BioCrystal, Ltd.
• Original Assignee: BioCrystal, Ltd.
• Inventors: Barbera-Guilem, Emilio, Thurston, Marlin O.
• Granted Patent: US 6,749,750 B2
• Time in Patent Office: Days
• US Class Current: 336/200
• CPC Class Codes: B03C 1/0332 using permanent magnets
• CPC Class Codes: B03C 1/035 Open gradient magnetic separators, i.e. separators in which the gap is unobstructed, characterised by the configuration of the gap
• CPC Class Codes: B03C 1/288 disposed at the outer circumference of a recipient
• CPC Class Codes: B03C 2201/18 Magnetic separation whereby the particles are suspended in a liquid
• CPC Class Codes: B03C 2201/26 for use in medical applications
• CPC Class Codes: B03C 2201/28 Parts being easily removable for cleaning purposes
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: C12M 23/10 Petri dish crystallising dishes B01L3/06
• CPC Class Codes: C12M 47/04 Cell isolation or sorting purging biological preparations of unwanted cells C12N5/0081, determining the presence or kind of microorganism C12Q1/04
• CPC Class Codes: H01F 7/0231 Magnetic circuits with PM for power or force generation
• CPC Class Codes: Y10S 428/90 Magnetic feature
• CPC Class Codes: Y10T 428/14 Layer or component removable to expose adhesive
• CPC Class Codes: Y10T 428/2848 Three or more layers
• CPC Class Codes: Y10T 428/32 Composite [nonstructural laminate] of inorganic material having metal-compound-containing layer and having defined magnetic layer

Abstract

A magnetic sheet assembly for application to a device adapted for magnetic separation, the magnetic sheet assembly comprising: a magnetic sheet; a permanent, pressure sensitive adhesive; a carrier sheet; and a non-permanent pressure sensitive adhesive. Also provided is a method of mounting and removably adhering the magnetic sheet assembly to a surface of a device for magnetic separation, the method comprising the steps of aligning the magnetic sheet assembly with the surface of the device; and pressing the aligned magnetic sheet assembly in placing its non-permanent adhesive face into adhesive contact with the surface of the device.

Claims

1. A magnetic sheet assembly for application to a device adapted for magnetic separation, wherein the magnetic sheet assembly comprises:

a magnetic sheet;

a permanent, pressure sensitive adhesive;

a carrier sheet; and

a non-permanent pressure sensitive adhesive.

2. The magnetic sheet assembly according to claim 1, further comprising a release liner which covers the non-permanent pressure sensitive adhesive

3. The magnetic sheet assembly according to claim 1, wherein the magnetic sheet is flexible.

4. The magnetic sheet assembly according to claim 1, wherein the magnetic sheet has a thickness in a range of from about 1 mm to about 2 mm.

5. The magnetic sheet assembly according to claim 1, wherein the magnetic sheet has a surface magnetic field having a field strength in a range of from about 450 to about 1200 gauss.

6. The magnetic sheet assembly according to claim 1, further comprising a layer provided on a surface of the magnetic sheet which is opposite to a surface of the magnetic sheet to which is bound the permanent adhesive;

wherein the layer is a material selected from the group consisting of a protective coating, a label, and a combination thereof.

7. The magnetic sheet assembly according to claim 1, wherein the magnetic sheet comprises a plurality of poles of alternating polarities being generally arranged as a plurality of parallel, spaced apart lines.

8. The magnetic sheet assembly according to claim 7, wherein the parallel, spaced apart lines may run along the surface of the magnetic sheet in a direction selected from the group consisting of side to side, and top to bottom.

9. The magnetic sheet assembly according to claim 7, wherein the spacing between the spaced apart lines is equidistant.

10. The magnetic sheet assembly according to claim 9, wherein the spacing is in a range of from spacing about 7 to about 12 poles per inch.

11. The magnetic sheet assembly according to claim 1, wherein the magnetic sheet comprises a magnetization pattern comprising a grid pattern formed by a first plurality of poles of alternating polarities being generally arranged as a plurality of parallel, spaced apart lines which are perpendicular with respect to, and intersect, a second plurality of poles of alternating polarities being generally arranged as a plurality of parallel, spaced apart lines.

12. The magnetic sheet assembly according to claim 11, wherein the spacing between parallel spaced apart lines is equidistant.

13. The magnetic sheet assembly according to claim 12, wherein the spacing of parallel, spaced apart lines is in a range of from spacing about 7 to about 12 poles per inch.

14. The magnetic sheet assembly according to claim 1, wherein the magnetic sheet comprises a magnetization pattern comprising a uniform poling in a first poling over substantially all of a planar surface of the magnetic sheet, and a second poling of an opposite polarity to that of first poling, wherein the second poling comprises a plurality of spaced apart cylindrical regions which are parallel in relation to the first poling.

15. The magnetic sheet assembly according to claim 1, wherein the magnetic sheet comprises a plurality of magnets bonded to a material selected from the group consisting of a fibrous material, and a non-fibrous material.

16. The magnetic sheet assembly according to claim 1, wherein the carrier sheet has a thickness in a range of from about 0.03 mm to about 0.25 mm.

17. The magnetic sheet assembly according to claim 1, wherein the carrier sheet has a thickness of about 2 mil.

18. The magnetic sheet assembly according to claim 1, wherein the pressure sensitive permanent adhesive has a thickness in a range of from about 0.3 mil to about 3 mil.

19. The magnetic sheet assembly according to claim 1, wherein the pressure sensitive permanent adhesive has a thickness of about 0.5 mil.

20. The magnetic sheet assembly according to claim 1, wherein the pressure sensitive non-permanent adhesive has a thickness in a range of from about 0.3 mil to about 3 mil.

21. The magnetic sheet assembly according to claim 1, wherein the pressure sensitive non-permanent adhesive has a thickness of about 0.5 mil.

22. The magnetic sheet assembly according to claim 1, wherein the pressure sensitive non-permanent adhesive is capable of releasing clearly from a surface of the device.

23. The magnetic sheet assembly according to claim 2, wherein the release liner has a thickness in a range of from about 1 mil to about 4 mil.

24. The magnetic sheet assembly according to claim 2, wherein the release liner has a thickness of about 2 mil.

25. The magnetic sheet assembly according to claim 2, wherein the permanent, pressure sensitive adhesive, carrier sheet, non-permanent pressure sensitive adhesive, and release liner are assembled to form a double-sided, pressure sensitive, adhesive laminate.

26. A method of mounting, and removably adhering, a magnetic sheet assembly according to claim 1 to a surface of a device for magnetic separation, the method comprising the steps of:

a) aligning the magnetic sheet assembly, having an exposed face comprising a non-permanent adhesive, with the surface of the device onto which it is desired to mount the magnetic sheet assembly; and

b) pressing the aligned magnetic sheet assembly in placing the non-permanent adhesive face into adhesive contact with the surface of the device to removably adhere the magnetic sheet assembly to the surface of the device.

27. The method according to claim 26, wherein the method further comprises the step of removing the magnetic sheet assembly from the device by lifting and separating the magnetic sheet assembly from the device to which it was in adhesive contact, and wherein the non-permanent adhesive releases clearly from the surface of the device.

28. A method of mounting, and removably adhering, a magnetic sheet assembly according to claim 2 to a surface of a device for magnetic separation, the method comprising the steps of:

a) removing the release liner from the magnetic sheet assembly so as to expose a face of the magnetic sheet assembly comprising the non-permanent adhesive;

b) aligning the magnetic sheet assembly, having an exposed face comprising a non-permanent adhesive, with the surface of the device onto which it is desired to mount the magnetic sheet assembly; and

c) pressing the aligned magnetic sheet assembly in placing the non-permanent adhesive face into adhesive contact with the surface of the device to removably adhere the magnetic sheet assembly to the surface of the device.

29. The method according to claim 28, wherein the method further comprises the step of removing the magnetic sheet assembly from the device by lifting and separating the magnetic sheet assembly from the device to which it was in adhesive contact, and wherein the non-permanent adhesive releases clearly from the surface of the device.

30. A magnetic sheet assembly for application to a device adapted for magnetic separation, wherein the magnetic sheet assembly comprises:

at least one magnetic sheet comprising a plurality of poles of alternating polarities being generally arranged as a pattern selected from the group consisting of a plurality of parallel, spaced apart lines, and a grid pattern formed by a first plurality of poles of alternating polarities being generally arranged as a plurality of parallel, spaced apart lines which are perpendicular with respect to, and intersect, a second plurality of poles of alternating polarities being generally arranged as a plurality of parallel, spaced apart lines; and

a double-sided pressure sensitive adhesive laminate comprised of a carrier sheet having applied on one side a permanent, pressure sensitive adhesive, and having applied on an opposite side a non-permanent, pressure sensitive adhesive, wherein the permanent, pressure sensitive adhesive is in adhesive contact with the at least one magnetic sheet in forming the magnetic sheet assembly.

31. The magnetic sheet assembly according to claim 30, further comprising a release liner which covers the non-permanent pressure sensitive adhesive.

32. The magnetic sheet assembly according to claim 30, wherein the at least one magnetic sheet has a surface magnetic field having a field strength in a range of from about 450 to about 1200 gauss.

33. A magnetic sheet assembly for application to a device adapted for magnetic separation, wherein the magnetic sheet assembly comprises:

at least one magnetic sheet comprising a magnetization pattern comprising a uniform poling in a first poling over substantially all of a planar surface of the magnetic sheet, and a second poling of an opposite polarity to that of first poling, wherein the second poling comprises a plurality of spaced apart cylindrical regions which are parallel in relation to the first poling; and

a double-sided pressure sensitive adhesive laminate comprised of a carrier sheet having applied on one side a permanent, pressure sensitive adhesive, and having applied on an opposite side a non-permanent, pressure sensitive adhesive, wherein the permanent, pressure sensitive adhesive is in adhesive contact with the at least one magnetic sheet in forming the magnetic sheet assembly.

34. The magnetic sheet assembly according to claim 33, further comprising a release liner which covers the non-permanent pressure sensitive adhesive.

36. The magnetic sheet assembly according to claim 33, wherein the at least one magnetic sheet has a surface magnetic field having a field strength in a range of from about 450 to about 1200 gauss.

38. The magnetic sheet assembly according to claim 37, further comprising a release liner which covers the non-permanent pressure sensitive adhesive.

39. The magnetic sheet assembly according to claim 37, wherein the plurality of magnets have a surface magnetic field having a field strength in a range of from about 450 to about 1200 gauss.

37. A magnetic sheet assembly for application to a device adapted for magnetic separation, wherein the magnetic sheet assembly comprises:

at least one magnetic sheet comprising a plurality of magnets bonded to a material selected from the group consisting of a fibrous material, and a non-fibrous material; and

a double-sided pressure sensitive adhesive laminate comprised of a carrier sheet having applied on one side a permanent, pressure sensitive adhesive, and having applied on an opposite side a non-permanent, pressure sensitive adhesive, wherein the permanent, pressure sensitive adhesive is in adhesive contact with the at least one magnetic sheet in forming the magnetic sheet assembly.