GB1577128A - Production of polymeric film laminates - Google Patents
Production of polymeric film laminates Download PDFInfo
- Publication number
- GB1577128A GB1577128A GB44724/76A GB4472476A GB1577128A GB 1577128 A GB1577128 A GB 1577128A GB 44724/76 A GB44724/76 A GB 44724/76A GB 4472476 A GB4472476 A GB 4472476A GB 1577128 A GB1577128 A GB 1577128A
- Authority
- GB
- United Kingdom
- Prior art keywords
- films
- nip rolls
- temperature
- nip
- temperatures
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B38/00—Ancillary operations in connection with laminating processes
- B32B38/0036—Heat treatment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
- B29C43/22—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of indefinite length
- B29C43/30—Making multilayered or multicoloured articles
- B29C43/305—Making multilayered articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
- B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
- B32B37/14—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers
- B32B37/16—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers with all layers existing as coherent layers before laminating
- B32B37/20—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers with all layers existing as coherent layers before laminating involving the assembly of continuous webs only
- B32B37/203—One or more of the layers being plastic
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2307/00—Properties of the layers or laminate
- B32B2307/30—Properties of the layers or laminate having particular thermal properties
- B32B2307/308—Heat stability
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2307/00—Properties of the layers or laminate
- B32B2307/50—Properties of the layers or laminate having particular mechanical properties
- B32B2307/514—Oriented
- B32B2307/516—Oriented mono-axially
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2307/00—Properties of the layers or laminate
- B32B2307/70—Other properties
- B32B2307/732—Dimensional properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2323/00—Polyalkenes
- B32B2323/04—Polyethylene
- B32B2323/043—HDPE, i.e. high density polyethylene
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2323/00—Polyalkenes
- B32B2323/10—Polypropylene
Landscapes
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Laminated Bodies (AREA)
- Lining Or Joining Of Plastics Or The Like (AREA)
- Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
Description
(54) PRODUCTION OF POLYMERIC FILM LAMINATES
(71) We, KONINKLIJKE EMBALLAGE
INDUSTRIE VAN LEER B.V., a Dutch body corporate, of Amsterdamseweg 206, Am stelveen, The Netherlånds, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: - This invention is concerned with the production of polymeric film laminates.
Thermoplastic polymeric film laminates are known, or have been described, which comprise two or more substantially monoaxially oriented layers, the direction of orientation of each layer being at an angle, preferably 45 , to the longitudinal dimension of the laminate and being at an angle, preferably 90 , to the direction of orientation of the adjacent layer(s). Such laminates are referred to herein, for convenience, as "cross-laminates".
The plies of cross-laminates may be formed of the same or different polymers.
Suitable thermoplastic polymers for the layers of the laminate are, for example, homo- and co-polymers of ethylene, polypropylene, poly- styrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, and ethylene/vinyl acetate copolymers. The most preferred materials are polypropylene and high density polyethylene.
The layers of such cross-laminates may be bonded together in any suitable way, for example, by adhesive, spot-welding, diff-welding, puncturing, lub-wel-ding, crystal-welding or by extrusionlamination (that is the extrusion of a thin film of molten thermoplastic polymer between converging preformed films in the nip of a pair of nip rolls in which the laminate is formed). The production of cross-laminate is 'déscribed, for example, in British Specification 1414785 Substantially all monoaxially oriented polymeric films are inherently anistropic and it is found that cross-laminates have a tendency to curl when exposed to changes in temperature due to this anistropy.Such curling, particularly such as tends to occur at cuts and at the edges of cross-laminates, can give rise to malfunctioning and stoppages in machines handling the crosslaminate, for example machines for forming cross-laminates into sacks.
Experiments have shown that conven- tionally produced cross-laminates have little tendency to curl at temperatures in the range 0 to 150 C, while curling at temperatures above and below this range, but the temperatures in this range are, of course, lower than those experienced in many parts of the world, particularly in the summer months.
We have found that it is possible to raise the range of temperatures at which crbss-laminates exhibit little tendency to curl by incorporating certain modifications in their method of production. In this way it is possible to obtain cross-laminates which exhibit little or- no tendency to curl (and which can therefore be handled in film-converting machines without difficulty) over the range of ambient temperatures found in temperate, sub-tropical and tropical climates.
According to the invention, there is provided a method of producing a cross-laminate from two or more substantially monoaxially oriented thermdplastic polymeric films, in which the films used have a thermal shrinkability of less than 3% and are passed into the nip of a pair of nip rolls wherein the laminate is formed, under minimum tension consistent with obtaining correct feeding, without wrinkling and fluting, of the films to the nip rolls, the films having been preheated to an elevated temperature (preferably at least 30 C) which is below the melting or softening temperature of any of the films.
In one embodiment of the inventlon, the elevated temperature at which the films are fed to the nip rolls may be about 1"C below the melting or softening temperature of any of the films.
It is, of course, necessary to apply some tension to the films as they are passed to the nip rolls in order to prevent wrinkling and fluting, and the requirement of the method according to the invention is that the tension used should be the minimum which is consistent with obtaining correct feeding of the films to the nip rolls.
The films are pre-heated before entering the nip rolls. Such pre-heating can be effected in any convenient way, for example, by the use of radiant or infra-red heaters positioned to effect radiation heating of the films before they enter the nip or, preferably, by passing the films over pre-heating rolls before they pass to the nip rolls. In general, the higher the temperature of the films when they are bonded together, the higher will be the upper limit of the range of temperatures in which the cross-laminate exhibits little or no tendency to curl. Preferred temperatures for pre-heating are from 30 to 70"C, more preferably from 50 to 60"C; we have found that these temperatures give satisfactory non-curling properties for most purposes.
The monoaxially oriented polymeric films used in the method according to the invention should not have excessive thermal shrinkability within the range of ambient temperatures contemplated for use since this property would give rise to temperature-responsive curling. Monoaxially oriented polymeric films are usually subjected to annealing after the stretching operation whereby they are oriented and such annealed monoaxially oriented films have an acceptably low thermal shrinkability for use in the process according to the invention. If the films have not previously been annealed, they should be annealed before or as part of the method according to the invention. In the latter case, annealing may constitute the pre-heating to which the films are subjected before passing to the nip rolls.
We find that films having a thermal shrinkability of less than 3 %, preferably less than 2%, are sutiable for use in the method according to the invention. Thermal shrinkability as referred to herein is determined by immersing a test strip of the film in water at 70"C for 2 minutes and measuring the percentage shrinkage in the orientation direction of the film after this treatment.
The cross-laminate is preferably bonded by extrusion lamination into the nip wherein the films are brought together or by adhesive bonding in the nip, one or more of the films having been pre-coated with a suitable adhesive.
In order that the invention may be more fully understood, the following example is given by way of illustration.
Example
A series of runs were carried out in which two films of uniaxially oriented high density polyethylene film (Amoco fas05), each having a nominal thickness of 26.5 microns and an average thermal shrinkability of 2.36% were bonded to form a cross-laminate. (In each film the direction of orientation was at 45" to the longitudinal dimension of the film and the films were brought together so that the directions of orientation were at 90 .) The films were extrusion laminated together, the extruded bonding layer (of 10 microns thickness) being polyethylene (USI Sn 553), in a pair of nip rolls.
Before passing to the nip rolls, each film was led over a heated roll so as to make half-roll contact therewith. The heated rolls were operated at temperatures from 55" to 60"C; the films were thereby heated to these temperatures.
Other process conditions were as follows: ambient temperature: 27.8"-30"C winder tension: 0.9-1.35 pounds/linear inch unwind tension: minimum line speed: 750 feet/min.
Samples of the cross-laminates produced were tested to determine the range of temperatures from 5"C upwards over which they showed no tendency to curl. The upper limit of the ranges varied from 32 to 46"C.
By way of comparison, the same extrusion laminating process was also carried out without pre-heating of the films.
The highest temperature at which the laminate obtained showed no tendency to curl was 9.5"C.
WHAT WE CLAIM IS:
1. A method of producing a crosslaminate from two or more substantially monoaxially oriented thermoplastic polymeric films, in which the films used have a thermal shrinkability (as herein defined) of less than 3% and are passed into the nip of a pair of nip rolls wherein the lam
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (8)
1. A method of producing a crosslaminate from two or more substantially monoaxially oriented thermoplastic polymeric films, in which the films used have a thermal shrinkability (as herein defined) of less than 3% and are passed into the nip of a pair of nip rolls wherein the lam
inate is formed, under minimum tension consistent with obtaining correct feeding, without wrinkling and fluting, of the films to be the nip rolls, the films having been preheated to an elevated temperature which is below the melting or softening temperature of any of the films.
2. A method according to claim 1, in which the films are at a temperature of at least 30"C.
3. A method according to claim 1 or 2, in which th e films are preheated to a temperature about 1"C below said melting or softening temperature.
4. A method according to any of claims 1 to 3, in which the films are preheated to a temperature of from 30 to to 70"C before entering the nip rolls.
5. A method according to any of claims 1 to 3, in which the films are pre-heated to a temperature of from 50 to 60"C before entering the nip rolls.
6. A method according to any of claims 1 to 5, in which the thermal shrinkability is less than 2%.
7. A method according to claim 1, substantially as herein described in the foregoing Example.
8. A cross-laminate, whenever produced by a method according to any of claims 1 to 7.
Priority Applications (13)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB44724/76A GB1577128A (en) | 1976-10-27 | 1976-10-27 | Production of polymeric film laminates |
NL7711602A NL7711602A (en) | 1976-10-27 | 1977-10-21 | METHOD FOR MANUFACTURING CROSS LAMINATES |
FR7732037A FR2369087A1 (en) | 1976-10-27 | 1977-10-25 | PROCESS FOR THE PREPARATION OF LAMINATES, AND CROSS LAMINATES THUS OBTAINED |
IE2182/77A IE45972B1 (en) | 1976-10-27 | 1977-10-26 | Production of polymeric film laminates |
AU30066/77A AU514027B2 (en) | 1976-10-27 | 1977-10-26 | Producing cross laminates of polymeric films |
LU78383A LU78383A1 (en) | 1976-10-27 | 1977-10-26 | |
DK476377A DK476377A (en) | 1976-10-27 | 1977-10-26 | PROCEDURE FOR THE PRODUCTION OF CROSS LAMINATES |
IL53226A IL53226A (en) | 1976-10-27 | 1977-10-26 | Method of producing cross laminates from thermoplastic polymeric films |
JP12920877A JPS53102384A (en) | 1976-10-27 | 1977-10-27 | Method for making cross laminate |
IT69404/77A IT1093021B (en) | 1976-10-27 | 1977-10-27 | PROCEDURE FOR THE MANUFACTURE OF LAMINATES CROSSED BY THERMOPLASTIC FILMS WITH A SINGLE AXIAL ORIENTATION |
ZA00776402A ZA776402B (en) | 1976-10-27 | 1977-10-27 | A method of producing cross laminates |
DE19772748318 DE2748318A1 (en) | 1976-10-27 | 1977-10-27 | METHOD FOR PRODUCING CROSS LAMINATES AND CROSS LAMINATES |
BE182106A BE860167A (en) | 1976-10-27 | 1977-10-27 | METHOD FOR MANUFACTURING CROSS LAMINATES |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB44724/76A GB1577128A (en) | 1976-10-27 | 1976-10-27 | Production of polymeric film laminates |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1577128A true GB1577128A (en) | 1980-10-22 |
Family
ID=10434479
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB44724/76A Expired GB1577128A (en) | 1976-10-27 | 1976-10-27 | Production of polymeric film laminates |
Country Status (12)
Country | Link |
---|---|
JP (1) | JPS53102384A (en) |
BE (1) | BE860167A (en) |
DE (1) | DE2748318A1 (en) |
DK (1) | DK476377A (en) |
FR (1) | FR2369087A1 (en) |
GB (1) | GB1577128A (en) |
IE (1) | IE45972B1 (en) |
IL (1) | IL53226A (en) |
IT (1) | IT1093021B (en) |
LU (1) | LU78383A1 (en) |
NL (1) | NL7711602A (en) |
ZA (1) | ZA776402B (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2189427A (en) * | 1986-03-26 | 1987-10-28 | Nat Res Dev | Improved oriented polymer films and tapes; and composite materials prepared therefrom |
US5024799A (en) * | 1987-09-14 | 1991-06-18 | Tredegar Industries, Inc. | Method for producing an embossed oriented film |
US5108814A (en) * | 1987-09-14 | 1992-04-28 | Tredegar Industries, Inc. | Embossed oriented film |
US5372268A (en) * | 1989-07-20 | 1994-12-13 | Minnesota Mining And Manufacturing | Pull tab innerseal |
EP0767738A1 (en) * | 1994-06-27 | 1997-04-16 | Mobil Oil Corporation | Cross-laminated multilayer film structures for use in the production of bank notes or the like |
EP0777573A1 (en) * | 1994-08-10 | 1997-06-11 | Mobil Plastics Europe, Inc. | Oriented hdpe laminates for easy directional opening |
SG81883A1 (en) * | 1991-10-23 | 2001-07-24 | Mobil Oil Corp | Hdpe/polypropylene film laminates |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0735106B2 (en) * | 1988-11-15 | 1995-04-19 | 信越化学工業株式会社 | Method of manufacturing polyimide film type flexible printed circuit board |
DE102006029397A1 (en) * | 2006-06-27 | 2008-01-03 | Ovd Kinegram Ag | Method for producing a laminated layer composite, laminated layer composite and its use |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1207611B (en) * | 1959-02-11 | 1965-12-23 | Hoechst Ag | Process for the improvement of all-round stretched films made of thermoplastic materials against impact loads |
GB1084721A (en) * | 1964-01-28 | 1967-09-27 | Rasmussen O B | Uniting polymer films |
FR1478823A (en) * | 1965-05-04 | 1967-04-28 | Ici Ltd | Films of oriented plastics, in particular of polyethylene terephthalate |
FR1481554A (en) * | 1965-05-28 | 1967-05-19 | Ici Ltd | Laminate manufacturing process |
US3783067A (en) * | 1969-07-03 | 1974-01-01 | Petzetakis Aristovoulos George | Composite synthetic-resin sheet material |
DE2028885C3 (en) * | 1969-07-03 | 1974-01-24 | Aristovoulos George Moschaton Piraeus Petzetakis (Griechenland) | Polyethylene laminate and process for its manufacture |
-
1976
- 1976-10-27 GB GB44724/76A patent/GB1577128A/en not_active Expired
-
1977
- 1977-10-21 NL NL7711602A patent/NL7711602A/en not_active Application Discontinuation
- 1977-10-25 FR FR7732037A patent/FR2369087A1/en not_active Withdrawn
- 1977-10-26 IE IE2182/77A patent/IE45972B1/en unknown
- 1977-10-26 IL IL53226A patent/IL53226A/en unknown
- 1977-10-26 LU LU78383A patent/LU78383A1/xx unknown
- 1977-10-26 DK DK476377A patent/DK476377A/en not_active Application Discontinuation
- 1977-10-27 ZA ZA00776402A patent/ZA776402B/en unknown
- 1977-10-27 IT IT69404/77A patent/IT1093021B/en active
- 1977-10-27 DE DE19772748318 patent/DE2748318A1/en not_active Withdrawn
- 1977-10-27 BE BE182106A patent/BE860167A/en unknown
- 1977-10-27 JP JP12920877A patent/JPS53102384A/en active Pending
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2189427A (en) * | 1986-03-26 | 1987-10-28 | Nat Res Dev | Improved oriented polymer films and tapes; and composite materials prepared therefrom |
GB2189427B (en) * | 1986-03-26 | 1989-11-22 | Nat Res Dev | Post forming processes for oriented polymer films and tapes; and polymer materials prepared therby. |
US5024799A (en) * | 1987-09-14 | 1991-06-18 | Tredegar Industries, Inc. | Method for producing an embossed oriented film |
US5108814A (en) * | 1987-09-14 | 1992-04-28 | Tredegar Industries, Inc. | Embossed oriented film |
US5372268A (en) * | 1989-07-20 | 1994-12-13 | Minnesota Mining And Manufacturing | Pull tab innerseal |
SG81883A1 (en) * | 1991-10-23 | 2001-07-24 | Mobil Oil Corp | Hdpe/polypropylene film laminates |
EP0767738A1 (en) * | 1994-06-27 | 1997-04-16 | Mobil Oil Corporation | Cross-laminated multilayer film structures for use in the production of bank notes or the like |
EP0767738A4 (en) * | 1994-06-27 | 1998-10-07 | Mobil Oil Corp | Cross-laminated multilayer film structures for use in the production of bank notes or the like |
EP0777573A1 (en) * | 1994-08-10 | 1997-06-11 | Mobil Plastics Europe, Inc. | Oriented hdpe laminates for easy directional opening |
EP0777573A4 (en) * | 1994-08-10 | 1998-09-30 | Mobil Plastics Europ Inc | Oriented hdpe laminates for easy directional opening |
Also Published As
Publication number | Publication date |
---|---|
IE772182L (en) | 1978-04-27 |
IE45972B1 (en) | 1983-01-12 |
BE860167A (en) | 1978-04-27 |
FR2369087A1 (en) | 1978-05-26 |
DE2748318A1 (en) | 1978-05-03 |
ZA776402B (en) | 1978-08-30 |
DK476377A (en) | 1978-04-28 |
JPS53102384A (en) | 1978-09-06 |
IL53226A (en) | 1980-06-30 |
LU78383A1 (en) | 1978-01-27 |
IT1093021B (en) | 1985-07-19 |
AU3006677A (en) | 1979-05-03 |
IL53226A0 (en) | 1977-12-30 |
NL7711602A (en) | 1978-05-02 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed [section 19, patents act 1949] | ||
PCNP | Patent ceased through non-payment of renewal fee |