Apparatus and Method for Manufacturing Laminated Sheet

• US 20080277059A1
• Filed: 09/22/2005
• Published: 11/13/2008
• Est. Priority Date: 09/30/2004
• Status: Active Grant

• Current Assignee: Toray Industries Incorporated
• Original Assignee: Toray Industries Incorporated
• Inventors: Furuno, Yoshiharu, Chigira, Nobutsugu, Nomura, Fumiyasu
• Granted Patent: US 7,858,006 B2
• Time in Patent Office: Days
• US Class Current: 156/314
• CPC Class Codes: B29C 2948/926 Flow or feed rate
• 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 48/07 Flat, e.g. panels
• CPC Class Codes: B29C 48/08 flexible, e.g. films
• CPC Class Codes: B29C 48/185 comprising six or more components, i.e. each component being counted once for each time it is present, e.g. in a layer
• CPC Class Codes: B29C 48/19 the layers being joined at their edges
• 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: B29L 2007/008 Wide strips, e.g. films, webs
• CPC Class Codes: B29L 2009/00 Layered products

Abstract

An apparatus is provided for manufacturing a laminated sheet wherein different molten resins are alternately laminated by providing a multitude of slits arranged at intervals and permitting the different molten resins to flow out from the adjacent slits. A value of a shortest flow path length (L1) to a longest flow path length (L2) of the molten resin that flows from an inlet to an outlet of the slit, which is a ratio of (L1)/(L2), is 0.5 or more. The slits include slits having different slit lengths. A flow quantity of the molten resin at the slit is changed by changing the intervals of the slits, length of the slits or by changing the temperature of the molten resin at the slits.

Claims

1. An apparatus for producing a laminated sheet, in which plural kinds of molten materials are laminated in plural layers as many as more than the number of said kinds of molten materials, comprising plural manifolds respectively used for supplying said respective molten materials, plural slits provided in correspondence to said respective manifolds and disposed with predetermined intervals kept between them so that said molten materials supplied into said respective manifolds can pass through the slits corresponding to said respective layers, and a laminating portion for laminating said molten materials having passed through said respective slits in order to form said layers, wherein each of said plural slits formed in correspondence to at least two manifolds out of said plural manifolds is such that in the width direction of said slit in the flow path of the corresponding molten material from the outlet of the corresponding manifold to the outlet of said slit, the ratio L1/L2 of the flow path length L1 of the first flow path portion on the side near said manifold to the flow path length L2 of the second flow path portion on the side far from said manifold is 0.5 or more.

2. An apparatus for producing a laminated sheet, according to claim 1, wherein the upstream section of said second flow path portion is formed as a flow path section kept inclined more downward in the downstream direction as it leaves from said manifold.

3. An apparatus for producing a laminated sheet, according to claim 2, wherein said inclined flow path section is formed as an inclined flow path section inclined straight.

4. An apparatus for producing a laminated sheet, according to claim 1, wherein the slit width at the outlet of each of the slits is from 10 mm to 200 mm.

5. An apparatus for producing a laminated sheet, according to claim 1, wherein the slit gap of each of the slits is from 0.1 mm to 5 mm.

6. An apparatus for producing a laminated sheet, according to claim 1, wherein the flow path length LC of the central flow path portion passing through the center in the width direction of each of the slits in said flow path of the slit is from 20 mm to 200 mm.

7. An apparatus for producing a laminated sheet, according to claim 1, wherein the number of said plural slits is from 10 to 1,000.

14. A method for producing a laminated sheet comprising the step of supplying plural kinds of molten materials respectively into the plural manifolds of the apparatus for producing a laminated sheet as set forth in any one of claims 1 through 13, the step of letting said molten materials supplied into said respective manifolds pass through the plural slits provided in correspondence to the respective manifolds of said apparatus, the step of laminating the streams of said respective molten materials having passed through the respective slits, by means of the laminating portion of said apparatus, for forming layer streams of said respective molten materials, the step of deriving said layer streams from said laminating portion, and the step of solidifying said respective molten materials of the derived layer streams, to form a laminated sheet comprising plural layers of respective materials formed by solidifying the respective molten materials.

8. An apparatus for producing a laminated sheet, in which plural kinds of molten materials are laminated in plural layers as many as more than the number of said kinds of molten materials, comprising plural slits disposed with predetermined intervals kept between them for allowing said respective molten materials to pass through the slits corresponding to said respective layers, and a laminating portion for laminating said respective molten materials having passed through said respective slits in order to form said layers, wherein the slit length of at least one slit of said plural slits and the slit length of at least one slit of the other slits are different from each other or the slit gap of at least one slit of said plural slits and the slit gap of at least one slit of the other slits are different from each other.

9. An apparatus for producing a laminated sheet, according to claim 8, wherein except or including the slits located at both ends of said plural slits, the slit lengths of said respective slits change monotonously in the arrangement direction of said slits from the slit at one end toward the slit at the other end.

10. An apparatus for producing a laminated sheet, according to claim 8, wherein the slit lengths of said respective slits are from 10 mm to 200 mm.

11. An apparatus for producing a laminated sheet, according to claim 8, wherein except or including the slits located at both ends of said plural slits, the slit gaps of plural slits corresponding to said respective molten materials are substantially the same.

12. An apparatus for producing a laminated sheet, according to claim 8, wherein the slit gaps of said respective slits are from 0.1 mm to 5 mm.

13. An apparatus for producing a laminated sheet, according to claim 8, wherein the number of said plural slits is from 10 to 1,000.

15. An apparatus for producing a laminated sheet, in which plural kinds of molten materials are laminated in plural layers as many as more than the number of said kinds of molten materials, comprising plural slits disposed with predetermined intervals kept between them for allowing said respective molten materials to pass through the slits corresponding to said respective layers, a laminating portion for laminating said respective molten materials having passed through said respective slits in order to form said layers, a device for deriving a multilayer molten material sheet composed of respective molten materials laminated by said laminating portion, from said laminating portion, a laminated sheet forming device for solidifying the respective molten materials of the derived multilayer molten material sheet, for forming a laminated sheet comprising said plural kinds of materials formed by solidifying said respective molten materials, wherein the flow rate of the corresponding one of said molten materials, flowing through at least one slit of said plural slits, can be changed based on the layer thickness information obtained by measuring the thicknesses of desired layers of the formed laminated sheet.

16. An apparatus for producing a laminated sheet, according to claim 15, wherein the flow rate of said molten material is changed by changing the slit gap and/or the slit length of said slit.

17. An apparatus for producing a laminated sheet, according to claim 16, wherein the measurement of the thicknesses of said layers is performed for all the respective layers of the laminated sheet, and that the flow rate of said molten material is changed by changing said slit gap.

18. An apparatus for producing a laminated sheet, according to claim 16, wherein the measurement of the thicknesses of said layers is performed for all the respective layers of the laminated sheet, and that the flow rate of said molten material is changed by changing said slit length.

19. An apparatus for producing a laminated sheet, according to claim 15, wherein the flow rate of said molten material is changed by changing the temperature of said molten material passing through the slit caused by changing the temperature of said slit.

20. An apparatus for producing a laminated sheet, according to claim 17, wherein the flow rate of said molten material is changed by making the slit gaps of the slits used for forming layers positioned in outer layer portions in the thickness direction of the laminated sheet larger than the slit gap of the slit used for forming a layer positioned in an inner layer portion.

21. An apparatus for producing a laminated sheet, according to claim 18, wherein the flow rate of said molten material is changed by making the slit lengths of the slits used for forming layers positioned in outer layer portions in the thickness direction of said laminated sheet shorter than the slit length of the slit used for forming a layer positioned in an inner layer portion.

22. An apparatus for producing a laminated sheet, according to claim 15, wherein the flow rate of said molten material is changed by mechanically or thermally changing the slit gap and/or the slit length of at least one slit of said plural slits.

23. An apparatus for producing a laminated sheet, according to claim 15, wherein if the measured thickness value of a given layer x in the thickness direction of said laminated sheet is T (x), the slit gap corresponding to the measured thickness value is d(x), the slit length is L(x), the intended thickness of said layer x is Ta(x), the intended slit gap corresponding to the intended thickness is da(x), and the intended slit length is La(x), then the flow rate of said molten material in the slit corresponding to said layer x is changed to satisfy the relation represented by the following formula:

Ta(x)/T(x)=[La(x)/L(x)]×

[d(x)³/da(x)³].

24. A method for producing a laminated sheet comprising the step of supplying plural kinds of molten materials respectively to the plural slits of the apparatus for producing a laminated sheet as set forth in any one of claims 15 through 23, and the step of forming a laminated sheet using said apparatus.