ELECTROMAGNETIC ADHESIVE AND METHOD OF JOINING MATERIAL THEREBY

• US 3,620,875 A
• Filed: 07/28/1969
• Issued: 11/16/1971
• Est. Priority Date: 12/11/1964
• Status: Expired due to Term

• Current Assignee: Emabond Incorporated
• Original Assignee: Nishan G. Chookazian, Richard J. Guglielmo Sr
• Inventors: Richard, J. Guglielmo Sr., Nishan, G. Chookazian
• Primary Examiner(s): John T. Goolkasian
• Assistant Examiner(s): George W. Moxon, II
• Application Number:
  US04/849,244
• Time in Patent Office: 841 Days
• Field of Search: 156/272-273,306,380 264/25-26 252/62.53-62.55,513 260/37M,39M,41B 117/227
• US Class Current: 156/272.4
• CPC Class Codes: B29C 65/00 Joining or sealing of preformed parts , e.g. welding of plastics materials; Apparatus therefor general aspects of processes or apparatus for joining preformed parts B29C66/00; using porous material formed by internal pressure generated therein for joining preformed parts B29C44/1228, B29C44/326
• CPC Class Codes: B29C 65/1425 Microwave radiation
• CPC Class Codes: B29C 65/1435 at least passing through one of the parts to be joined, i.e. transmission welding
• CPC Class Codes: B29C 65/148 placed at the interface
• CPC Class Codes: B29C 65/1483 coated on the article
• CPC Class Codes: B29C 65/3612 comprising fillers
• CPC Class Codes: B29C 65/368 with a polymer coating
• CPC Class Codes: B29C 65/4815 Hot melt adhesives, e.g. thermoplastic adhesives
• CPC Class Codes: B29C 65/4855 characterised by their physical properties, e.g. being electrically-conductive
• CPC Class Codes: B29C 65/4875 being spherical, e.g. particles or powders
• CPC Class Codes: B29C 65/489 being metals
• CPC Class Codes: B29C 65/522 by spraying, e.g. by flame spraying
• CPC Class Codes: B29C 65/523 by dipping
• CPC Class Codes: B29C 65/526 by printing or by transfer from the surfaces of elements carrying the adhesive, e.g. using brushes, pads, rollers, stencils or silk screens
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/91411 of the parts to be joined, e.g. the joining process taking the temperature of the parts to be joined into account
• CPC Class Codes: B29C 66/91651 by controlling or regulating the heat generated by Joule heating or induction heating
• CPC Class Codes: B29C 66/91921 in explicit relation to another temperature, e.g. to the softening temperature or softening point, to the thermal degradation temperature or to the ambient temperature
• CPC Class Codes: B29C 66/949 characterised by specific time values or ranges
• CPC Class Codes: B29K 2023/00 Use of polyalkenes or derivatives thereof as moulding material
• CPC Class Codes: B29K 2025/06 : PS, i.e. polystyrene
• CPC Class Codes: B29K 2059/00 : Use of polyacetals , e.g. POM, i.e. polyoxymethylene or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2077/00 : Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• CPC Class Codes: C08J 5/124 : using adhesives based on a macromolecular component
• CPC Class Codes: C08J 5/125 : Adhesives in organic diluents
• CPC Class Codes: C08J 5/128 : Adhesives without diluent
• CPC Class Codes: C08K 3/08 : Metals
• CPC Class Codes: C08L 2666/54 : Inorganic substances
• CPC Class Codes: C09J 201/00 : Adhesives based on unspecified macromolecular compounds
• CPC Class Codes: C09J 5/06 : involving heating of the applied adhesive
• CPC Class Codes: H01F 1/28 : dispersed or suspended in a bonding agent
• CPC Class Codes: Y10S 428/90 : Magnetic feature

Abstract

Electromagnetic adhesive comprised of a mixture of a thermoplastic material and ferromagnetic particles having mesh sizes of from 20-200 mesh. The adhesives are employed to bond thermoplastics by the use of inductive heating, the bonding being effected in period of less than two minutes.

Claims

2. The method as defined in claim 1 wherein the weight ratio of ferromagnetic particles passing through a 20 mesh screen and not passing through a 200 mesh screen to thermoplastic material is from about 1:

1 to about 2;

1.

3. The method as defined in claim 2 wherein the ferromagnetic particles is a member selected from the group consisting of iron, cobalt, nickel, alloys containing nickel, alloys containing cobalt and alloys containing iron.

4. The method as defined in claim 3 wherein the thermoplastic material is selected from the group consisting of polyolefins, polystyrenes, polyamides and acetals.

5. The method as defined in claim 3 wherein the electromagnetic field has a field intensity of from about 1 to about 30 kilowatts and a frequency from about 5 to about 30 megacycles.

6. The method as defined in claim 3 wherein the ferromagnetic particles are of a size which pass through a 40 mesh screen and do not pass through a 100 mesh screen.

7. An electromagnetically activatable adhesive composition, comprising a substantially uniform mixture of thermoplastic material and ferromagnetic particles, said ferromagnetic particles having particle sizes which pass through a 20 mesh screen and do not pass through a 200 mesh screen, whereby upon application of an induced electromagnetic field said particles are rapidly heatable by hysteresis and eddy current effects to a temperature above the Curie temperature of said particles.

8. The adhesive as defined in claim 7 wherein the weight ratio of ferromagnetic particles passing through a 20 mesh screen and not passing through a 200 mesh screen to thermoplastic material is from about 1:

1 to about 2;

1.

9. The adhesive composition as defined in claim 8 wherein the ferromagnetic particles is a member selected from the group consisting of iron, cobalt, nickel, alloys containing nickel, alloys containing cobalt and alloys containing iron.

10. The adhesive as defined in claim 9 wherein the thermoplastic material is selected from the group consisting of polyolefins, polystyrenes, polyamides and acetals.

11. The adhesive composition as defined in claim 9 wherein the composition is in the form of a solid sheet.

12. The adhesive composition as defined in claim 9 wherein the composition is in the form of a ribbon.

13. The adhesive as defined in claim 9 wherein the ferromagnetic particles are of a size which pass through a 40 mesh screen and do not pass through a 100 mesh screen.