Method of making container article having heatable stratified material portion

• US 3,996,090 A
• Filed: 03/07/1974
• Issued: 12/07/1976
• Est. Priority Date: 01/06/1972
• Status: Expired due to Term

• Current Assignee: William C. Heller Jr
• Original Assignee: William C. Heller Jr
• Inventors: Leatherman, Alfred F.
• Primary Examiner(s): Van Horn, Charles E.
• Assistant Examiner(s): Wityshyn, M. G.
• Application Number:
  US05/448,985
• Time in Patent Office: 1,006 Days
• Field of Search: 156/69, 156/272, 156/244, 156/273, 156/242, 264/211, 264/177 R, 264/209
• US Class Current: 156/244.13
• CPC Class Codes: B29C 48/001 Combinations of extrusion moulding with other shaping operations
• CPC Class Codes: B29C 48/0017 combined with blow-moulding or thermoforming
• CPC Class Codes: B29C 48/0018 combined with shaping by orienting, stretching or shrinking, e.g. film blowing B29C48/0017 takes precedence
• CPC Class Codes: B29C 48/0019 combined with shaping by flattening, folding or bending
• CPC Class Codes: B29C 48/0022 combined with cutting
• CPC Class Codes: B29C 48/07 Flat, e.g. panels
• CPC Class Codes: B29C 48/08 flexible, e.g. films
• CPC Class Codes: B29C 48/09 Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
• CPC Class Codes: B29C 48/16 Articles comprising two or more components, e.g. co-extruded layers
• CPC Class Codes: B29C 48/21 the layers being joined at their surfaces
• CPC Class Codes: B29C 48/307 specially adapted for bringing together components, e.g. melts within the die
• CPC Class Codes: B29C 48/3363 using a layered die, e.g. stacked discs
• CPC Class Codes: B29C 48/49 using two or more extruders to feed one die or nozzle
• CPC Class Codes: B29C 51/14 using multilayered preforms or sheets
• CPC Class Codes: B29C 65/1425 Microwave radiation
• CPC Class Codes: B29C 65/3612 comprising fillers
• CPC Class Codes: B29C 65/368 with a polymer coating
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/1222 comprising at least a lapped joint-segment
• CPC Class Codes: B29C 66/1224 comprising at least a butt joint-segment
• CPC Class Codes: B29C 66/1226 : comprising at least one bevelled joint-segment
• CPC Class Codes: B29C 66/24221 : being circular B29C66/51 takes precedence
• CPC Class Codes: B29C 66/53461 : joining substantially flat covers and/or substantially flat bottoms to open ends of container bodies
• CPC Class Codes: B29C 66/542 : joining hollow covers or hollow bottoms to open ends of container bodies
• CPC Class Codes: B29C 66/5432 : joining hollow covers and hollow bottoms to open ends of container bodies
• CPC Class Codes: B29C 66/545 : one hollow-preform being placed inside the other
• CPC Class Codes: B29C 66/612 : Making circumferential joints
• CPC Class Codes: B29C 66/73921 : characterised by the materials of both parts being thermoplastics
• CPC Class Codes: B29C 66/8322 : Joining or pressing tools reciprocating along one axis
• CPC Class Codes: B29C 69/00 : Combinations of shaping techniques not provided for in a single one of main groups B29C39/00 - B29C67/00, e.g. associations of moulding and joining techniques; Apparatus therefore B29C48/001 takes precedence
• CPC Class Codes: B29K 2995/0008 : Magnetic or paramagnetic

Abstract

A container article is formed from a stratified material having an inductively heatable layer. A first article part has a thermally joinable region. A second stratified article part, formed by coextrusion, has a layer containing an oxide susceptor. The container parts are assembled and subjected to an alternating magnetic field to heat the susceptor and thermally join the parts.

Claims

1. A method of making a closed container article having a plurality of parts joined along closure seams comprising the steps of:

providing a first article part having a container article element region and a first thermally joinable region;

providing a second article part by coextrusion through layer forming dies by,

providing a plurality of fusible thermoplastic compositions at first locations removed from the layer forming dies,

moving the compositions from the first location towards the dies, the movement of at least one of the compositions being accompanied by an agitation thereof,

uniformly providing in one of the compositions during its movement toward the die and by means of its agitation, a particulate ferromagnetic oxide susceptor;

heating the compositions to a malleable and fusible state during the movement, and

forcing the compositions through respective dies into intimate contact with each other while in the malleable and fusible state to form a sheet having joined stratified layers of the compositions coextensive with its dimensions,

forming the stratified sheet into a second container article part having a container article element region and a second thermally joinable region contiguous with the article element region, each of said regions containing the susceptor laden layer;

juxtapositioning the first and second article parts so that the thermally joinable regions of said first and second article parts are contiguous along a closure seam;

applying an alternating magnetic field to the thermally joinable region of said second article part to heat the regions; and

bringing the contiguous regions of the first and second article parts into contact to effect thermal joinder between the two to seal the part into the container article.

2. The method according to claim 1 wherein the step of providing the particulate susceptor is further defined as providing a susceptor selected from a material class consisting of the oxides of iron having ferromagnetic properties.

3. The method according to claim 2 wherein the step of providing the particulate susceptor is further defined as providing a susceptor in a size range of submicron to 20 microns.

4. The method according to claim 2 wherein the step of applying the alternating magnetic field is further defined as applying an alternating magnetic field having a frequency of 0.45 to 5000 megahertz.

5. The method according to claim 2 including the step of incorporating a masking agent in a composition other than the one containing the particulate susceptor.

6. The method according to claim 1 further defined as forming one of said container article part as a receptacle having an opening with a thermally joinable region about the opening and forming the other article part as a receptacle closure for closing said opening with another thermally joinable region mateable with the first thermally joinable region.

7. The method according to claim 6 wherein the step of providing said first container article part is further defined as forming a tube having a pair of first thermally joinable regions adjacent either end of said tube and wherein the step of forming the said second article part is further defined as forming a pair of plugs for the ends of said tube having annular second thermally joinable regions mateable with said first thermally joinable regions.

8. The method according to claim 6 wherein the step of forming said second article part is further defined as forming a tubular receptacle having a pair of second thermally joinable regions adjacent either end of said tube and wherein the step of providing said first container article part is further defined as forming a pair of plugs for the ends of said tube having annular first thermally joinable regions mateable with said second thermally joinable regions.

9. The method according to claim 6 further defined as forming the first container article part as the receptacle and said second article part as the closure.

10. The method according to claim 9 wherein the step of providing said first container article part is further defined as forming a tubular receptacle having a flange-like first thermally joinable region about the open end thereof and wherein the step of forming said second container article part is further defined as forming a circular lid having a flange-like second thermally joinable region mateable with said first thermally joinable region.

11. The method according to claim 1 including the step of selecting fusible thermoplastic compositions having properties desired in the assembled container article.

12. The method according to claim 1 wherein the incorporation step is further defined as incorporating the particulate susceptor in quantities of up to 30% by weight with respect to the one composition.