APPARATUS FOR MANUFACTURING MULTILAYER POLYMERIC FILMS

• US 20110272832A1
• Filed: 05/06/2011
• Published: 11/10/2011
• Est. Priority Date: 05/07/2010
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Neavin, Terence D., Fay, William T., Biegler, Robert M.
• Granted Patent: US 9,630,356 B2
• Time in Patent Office: Days
• US Class Current: 264/1.7
• CPC Class Codes: B29C 48/08 flexible, e.g. films
• 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 48/495 Feed-blocks extrusion moulding of multi-component articles B29C48/16
• CPC Class Codes: B29C 48/71 for layer multiplication extrusion of multi-component articles B29C48/16

Abstract

A feedblock including a first packet creator that forms a first packet including a first plurality of polymeric layers, the first plurality of layers including at least four first individual polymeric layers; and a second packet creator that forms a second packet including a second plurality of polymeric layers, the second plurality of layers including at least four second individual polymeric layers, wherein the first and second packet creators are configured such that, for each packet creator, respective individual polymeric layers of the plurality of polymeric layers are formed at approximately the same time. The feedblock may include a packet combiner that receives and combines the first and second primary packets to form a multilayer stream. In some examples, at least one of the first and second primary packets may be spread in the cross-web direction prior to being combined with one another.

Claims

1. An assembly for manufacturing a multilayer film, the assembly comprising:

a first flow channel configured to received a first primary packet, the first primary packet including a first plurality of polymeric layers; and

a second flow channel configured to received a second primary packet, the primary second packet including second plurality of polymeric layers,

wherein the first channel and the second channel are configured to spread at least one of the first and second primary packets in a cross-web direction and, after spreading the at least one of the first and second primary packets in the cross-web direction, combine the first and second primary packets to form a multilayer flow stream including the first and second plurality of polymeric layers.

2. The assembly of claim 1, wherein the first channel includes a first spreading manifold configured to spread the first primary packet in the cross-web direction and the second channel includes a second spreading manifold configured to spread the second primary packet in the cross-web direction.

3. The assembly of claim 2, further comprising an extrusion die including the first and second spreading manifold.

4. The assembly of claim 1, further comprising a third flow channel configured to receive an additional layer flow, wherein the third channel is configured to combine the additional layer flow with the first and second packets to form the multilayer flow stream.

5. The assembly of claim 4, wherein the additional layer flow comprises a core layer flow for forming a core layer between the first and second primary packets in the multilayer flow stream.

6. The assembly of claim 4, wherein the additional layer flow comprises at least one skin layer flow for forming at least one skin layer adjacent to at least one of the first packet or the second packet.

7. The assembly of claim 4, wherein third flow channel is configured to combine the additional layer flow with at least one of the first packet or second packet prior to the spreading of at least one of the first packet or second packet in the cross-web direction.

8. The assembly of claim 4, wherein the third channel is configured to spread the additional layer flow in the cross-web direction prior to being combined with the first and second packets.

9. The assembly of claim 1, further comprising a first packet creator configured to generate the first primary packet with a first cross-web width and second packet creator to generate the second primary packet with a second cross-web width, wherein the first flow channel is configured to receive the first primary packet with the first cross-web width and spread the first primary packet to a third cross-web width greater than the first cross-web width, and the second flow channel is configured to receive the second primary packet with the second cross-web width and spread the second primary packet to a fourth cross-web width greater than the second cross-web width.

10. The assembly of claim 1, wherein the first and second packets have substantially the same cross-web width when combined with one another.

11. The assembly of claim 1, wherein the multilayer flow stream is manufactured into a multilayer optical film.

12. A method comprising:

receiving a first primary packet via a first flow channel, the first primary packet including a first plurality of polymeric layers;

receiving a second primary packet via a second flow channel, the second packet including second plurality of polymeric layers;

spreading at least one of the first primary packet and second primary packet in a cross-web direction; and

combining the first primary packet and second primary packet with one another after spreading at least one of the first packet and second packet in the cross-web direction to form a multilayer flow including the first and second plurality of polymeric layers.

13. The method of claim 12, wherein the first channel includes a first spreading manifold configured to spread the first primary packet in the cross-web direction and the second channel includes a second spreading manifold configured to spread the second primary packet in the cross-web direction.

14. The method of claim 13, wherein the first and second spreading manifolds are formed by an extrusion die configured to combine the first and second primary packets.

15. The method of claim 12, further comprising:

receiving an additional layer flow via a third flow channel; and

combining the additional layer flow with the first and second primary packets to form the multilayer flow stream.

16. The method of claim 15, wherein the additional layer flow comprises a core layer flow for forming a core layer between the first and second primary packets in the multilayer flow stream.

17. The method of claim 15, wherein the additional layer flow comprises at least one skin layer flow for forming at least one skin layer adjacent to at least one of the first packet or the second packet in the multilayer flow stream.

18. The method of claim 15, further comprising combining the additional layer flow with at least one of the first primary packet or second primary packet prior to spreading the at least one first primary packet or second primary packet in the cross-web direction.

19. The method of claim 15, further comprising spreading the additional layer flow in the cross-web direction prior to combining the additional layer flow with the first and second primary packets.

20. The method of claim 12, further comprising:

generating the first primary packet via a first packet generator, the first primary packet having a first cross-web width;

generating the second primary packet via a second packet creator, the second packet having a second cross-web width,

wherein receiving the first primary packet via the first flow channel comprises receiving the first packet having the first cross-web width via the first flow channel, and receiving the second primary packet via the second flow channel comprises receiving the second packet having the second cross-web width via the second flow channel, and

wherein spreading the at least one of the first primary packet and second primary packet in a cross-web direction comprising spreading the first primary packet to a third cross-web width greater than the first cross-web width and spreading the second primary packet to a fourth cross-web width greater than the second cross-web width.

21. The method of claim 12, wherein the first and second packets have substantially the same cross-web width when combined with one another.

22. The method of claim 12, further comprising manufacturing the multilayer flow stream into a multilayer optical film.

23. An assembly for manufacturing a multilayer film, the assembly comprising:

means for receiving a first primary packet via a first flow channel, the first primary packet including a first plurality of polymeric layers;

means for receiving a second primary packet via a second flow channel, the second packet including second plurality of polymeric layers;

means for spreading at least one of the first primary packet and second primary packet in a cross-web direction; and

means for combining the first primary packet and second primary packet with one another after spreading at least one of the first packet and second packet in the cross-web direction to form a multilayer flow including the first and second plurality of polymeric layers.