JPH01320134A - Polymeric laminate and method for correcting curling thereof - Google Patents

Abstract

PURPOSE:To facilitate the handling of a laminate by a method wherein the radius of curvature of curling is made to be larger than the specified value by causing shrink plastic deformation on a part of a curled polymeric laminate produced by laminating two layers or more of polymer. CONSTITUTION:The correction concerned is to make the radius of curvature or curling more than and equal to 10cm by causing shrink plastic deformation on a part of a curled polymeric laminate. The curled polymeric laminate 45 is subject to either or both of a process, which consists of the longitudinal sliding of the laminate under tension over the curved surface of a bar 42, which is provided at an angle of 0-80 degrees to the width direction of the laminate and the radius of curvature of which is not less than 0.001mm and less than 25mm under the condition that the curled outside of the laminate faces the inside of the curved surface, and a process, which consists of the longitudinal sliding of the laminate under tension over the curved surface of a bar 43, which is provided at an angle of 0-80 degrees to the width direction of the laminate and the radius of curvature of which is not less than 0.001mm and less than 25mm under the condition that the curled outside of the laminate faces the inside of the curved surface, once or more. The turning-up angle of the laminate 45 is 20-179 degrees and the tension applied to the laminate 45 is not less than 20g/cm<2>. The correction is done under the condition that the temperature of the laminate is kept at a temperature not higher than the glass transition temperature of the polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a polymer laminate in which two or more polymer layers are laminated.

[Conventional technology and its issues]

A polymer laminate is a laminate made by laminating polymer films or sheets (hereinafter simply referred to as films), and can be used as packaging materials, flexible circuit boards, flexible circuit boards, cover films for flexible circuit boards, and wire coatings. It is widely used in materials, protective films, heat insulating materials, protective films, heat insulating materials, heath films for magnetic tapes, floppy disks, etc., solar cell substrates, solar cell substrates, capacitors, sensors, insulating materials, etc.

When these polymer laminates are processed and used for the various purposes mentioned above, the dimensional difference between the eyebrows of the polymer is within an appropriate range (within 5%, preferably 1%).
(within) and is preferably flat or nearly flat.

- When processing or using sulfur, a polymer laminate in a "nearly flat state" can be considered to be a state in which the radius of curvature of the curl is 10 cm or more in practical terms.

Polymer laminates can be produced by laminating a polymer on a base film by methods such as dry lamination or extrusion lamination; by co-extruding the polymer for the base film with other polymers; or by dissolving the polymer in a solvent on the base film. It is manufactured by applying a polymer and drying it. However, in the manufacturing process of ordinary polymer laminates, the dimensional difference between the layers is outside the above-mentioned appropriate range due to differences in the coefficient of thermal expansion and thermal history of the polymers. Those skilled in the art are struggling to deal with curls caused by such dimensional differences between the eyebrows.

For example, a polymer laminate manufactured by applying a solution containing a dissolved polymer onto a polymer thin film and drying it has a coefficient of thermal expansion,
Due to differences in thermal shrinkage rates, drying shrinkage, etc., the material often becomes curled, which is inconvenient in practical applications such as lamination and bonding.

Therefore, a polymer laminate obtained by eliminating this curl is very useful industrially.

[Means for Solving the Problems] That is, the present invention has been made from this point of view. It is a polymer laminate that is deformed and has a radius of curvature of 10 cm or more.

This can be obtained, for example, as follows, by turning a curled polymer laminate to zero in its width direction.
A step of sliding longitudinally under tension with the curled outside side inward on the curved surface of a first bar with a radius of curvature of 0.001 or more and less than 25 -, which is provided at an angle of ~80 degrees,
provided at an angle of O to -80 degrees with respect to the width direction,
The step of sliding the laminate under tension in the longitudinal direction on the curved surface of a bar with a radius of curvature of o,oot or more and less than 25 mm with the curled outside facing inside is carried out one or more times. 4 things! This is a method for straightening curls of polymerized laminates, and in each of the above steps, the folding angle is expressed as the angle between the plane to which the laminate introduced into the bar belongs and the 4A laminate extracted from the bar. , the folding angle is from 20 degrees to 179
In the above method, the tension state in each step is expressed as the tension applied to the laminate, and the tension is 20
g/cm or more, and the temperature of the laminate is below the glass transition temperature of the polymer, and after the final step, the laminate is heated to the glass transition temperature of the polymer. 1° below the glass transition temperature of the glass transition temperature polymer
The above method involves curing at a temperature lower than C for 10 minutes or more,
Further, the present invention will be explained in detail below.

In the present invention, the target polymer laminate can be obtained by laminating another polymer film on a polymer film. The type of this polymer is not particularly limited, but non-limiting examples include aromatic or aliphatic polyamide,
Examples include aromatic or aliphatic polyimide, polyether sulfone, polyethylene terephthalate, polyether ether ketone, polypropylene, polystyrene, polyethylene, polyvinyl chloride, polytetrafluoroethylene, or copolymers thereof.

As a method for producing a polymer laminate, for example, a method of laminating the polymer onto a base film by a method such as dry lamination, extrusion lamination, etc. - a method of co-extruding the polymer for the base film and other polymers; or a method of co-extruding the polymer for the base film with another polymer; It is manufactured by a method such as applying a polymer dissolved in a solvent to a surface and drying it, but the method is not particularly limited.

Moreover, the film thickness of the polymer laminate is usually 1-1000 μm, preferably 1-200 μm. In addition, the thickness of each film layer constituting the laminate is 0.5 to 500
It is preferably about 0.5 to 100 μ.

The present invention will be described below with reference to the drawings.

Normally, polymer laminates curl in both the longitudinal and width directions due to differences in thermal expansion and thermal contraction coefficients, and due to drying shrinkage when subjected to a drying process, as shown in Figure 1. in many cases.

A curl-free polymer laminate, ie a curl-corrected polymer laminate, can basically be obtained by the following method. That is, the polymer laminate is continuously slid over the curved surface of the bar with the curled outside facing inward. The polymer laminate is made such that on the curved surface of the bar, the outer polymer is stretched and the inner polymer is contracted, so that the radius of curvature of the curl is within the desired range, i.e. 10
cm or more. One important feature of the present invention is that a portion of the polymeric laminate is thus subjected to "shrinkage compositional deformation" to correct curl. In this regard, please refer to the detailed description below. More specifically regarding the above, for example, the polymer laminate is placed on the curved surface of a bar provided at an angle (line angle) of 0 to 80 degrees with respect to its width direction, with the curled outside side inside. A step of sliding the laminate in the longitudinal direction in a tensioned state, on the curved surface of the bar provided at an angle (line angle) of 0 to -80 degrees with respect to the width direction of the laminate, with the curled outside side inside. The process of sliding the laminate in the longitudinal direction under tension is
The polymer laminate can be decurled by performing each step one or more times in any order. In addition, the line angle referred to in the present invention is the angle seen from the side that is not in direct contact with the bar among the two sides of the advancing polymer, and the counterclockwise direction is a positive angle and the clockwise direction is a negative angle. Let it be an angle. Also,
! If the curl of the f-laminate is substantially only in the longitudinal direction, the curl can be corrected by carrying out the process twice.

If the line angle exceeds 80 degrees, running becomes unstable and it is necessary to use a longer bar, making it difficult to keep the accuracy of the linearity within ±11. Preferably, the angle is substantially within ±80 degrees.

Further, it is also a preferable embodiment to carry out a step of curing for about 10 minutes or more in an atmosphere at a temperature shown later after the above-mentioned final step.

The basic technical idea of the present invention is that, as shown in FIG. When moving under tension along the circumference of the bar, with the outer polymer d inside, the polymer C is stretched and the polymer d is "shrinked". By making the lengths of the polymer C and the polymer C almost equal, the curl of the laminate is removed. As described above, a major feature of the present invention is that the curl is corrected by "shrinkage plastic deformation" of a part of the polymer laminate. However, in the field of plastic processing of ordinary polymers, resins are
While "stretch plastic deformation" is a very common operation, straightening curl by "contraction plastic deformation" of a part of a polymer laminate is a novel method discovered for the first time by the present inventors. This is because it should be called manipulation. It must be said that the fact that curls can be corrected very effectively by carrying out such an operation is a surprising finding that could never have been expected by those skilled in the art.

Furthermore, in implementing this technical idea, it is preferable to carry out the process separately into a first step and a second step, as illustrated in FIG. 3. In the first step, when the laminate A passes a first bar 11 placed at an angle of, for example, 45 degrees to its direction of travel, the curl is straightened at right angles to the bar. Further, in the second step, when the laminate A passes through a second bar 12 placed at, for example, 145 degrees to the direction of travel, the curl is corrected at right angles to the bar. In this way, the laminate A is attached to the first bar 1.
By passing through both the first and second bars 12, curls in all planes of the laminate are corrected. The degree of reduction in this curl is determined by the tension, speed, and number of times when the laminate A slides on the bar in the advancing direction, and the laminate A shown in Fig. 2.
It can be adjusted by controlling the tension applied to the bar, the folding angle when the laminate A is folded back across the bar, and the like.

Further, the absolute values of the angles of the first bar and the second bar with respect to the width direction of the laminate may not be equal.

This is illustrated in FIG. In this example, in the first step, when the laminate A is placed at 20 degrees to its width and passes through the first bar 21, the curl is reduced in the direction perpendicular to the bar. Furthermore, in a second step, when the laminate A passes through a second bar 22 placed at 170 degrees with respect to its width, the curl is reduced in a direction perpendicular to the bar. In this way, the laminate A passes through both the first bar 21 and the second bar 22, thereby reducing the curling of the laminate in all plane directions.

In addition, the curl of the polymer laminate has directionality, and the width direction (T
When there is a difference between the D force direction and the longitudinal direction (MD force direction, the angle formed by the first bar and the second bar is not necessarily 90 degrees. For example, if there is a difference between the If a large tension is applied when casting, the curl in the MD force direction will be larger than that in the TD force direction.In order to make such a polymer laminate curl-free, the fifth
In the figure, the angle of the first bar 31 with respect to the width direction of the laminate A is, for example, 20 degrees, and the angle of the second bar 32 with respect to the width direction of the laminate is, for example, 120 degrees. With such a line angle, the correction of the curl in the MD force direction is greater than that in the TD force direction, and it is possible to produce a polymer laminate in which the curl in the MD force direction and the TD force direction is equal and small. In this case, the degree of reduction in curl is determined by the tension, speed, number of times and the second
The tension applied to the laminate shown in the figure can be adjusted by controlling the folding angle when the laminate A is folded back across the bar. Furthermore, after straightening the curl as necessary, it is preferable to cure the laminate at a temperature 10°C or more lower than the glass transition temperature of the polymer.
This is because temporary small deformations other than stretching plastic deformation and shrinkage plastic deformation of the polymer caused by passing through the bar remain, and these are removed by curing. In this way, it is possible to straighten the curl of the polymeric laminate. In addition, even in the correction of curls accompanied by plastic deformation, there is virtually no deterioration in the quality of the polymer laminate, such as adhesive properties and film properties.

In order to facilitate understanding of the present invention, the present invention will be described in more detail with reference to the accompanying drawings. Figure 6 shows that rectangular glass plates with curved corners, as shown in Figure 8, are used as the first and second bars, and the polymer that is not in direct contact with the bars is deformed by stretching. , and is a schematic diagram illustrating an example of a situation in which curl correction is performed by shrinking and plastically deforming a polymer that is in direct contact with a bar.

The polymer laminate 45 wound around the roll 41 moves in the direction of the arrow, and the first bar is set at an angle α (line angle) of 0 to 80 degrees with respect to the width direction of the laminate. 42
(In Figure 6, the laminate is installed so that α1 to the width direction is 45 degrees). while touching, the folding angle is, for example, 60 degrees (that is, the plane to which the laminate supplied to the first bar 42 belongs and the plane to which the laminate drawn from the bar 42 belongs form an angle of 60 degrees). state). The laminate from the first bar 42 moves in the direction of the arrow and has a width of 0 to 80 with respect to the width of the laminate.
A second bar 4 installed at an angle α2 (line angle) of degrees
3 (in Figure 6, the laminate is installed so that α2 is 145 degrees with respect to the width direction). While the union is in contact, the folding angle is, for example, 60 degrees (that is, the plane to which the laminate supplied to the second bar 43 belongs and the plane to which the laminate drawn from the bar 43 belongs form an angle of 60 degrees). state), is further moved in the direction of the arrow, and is wound onto a roll 44. Note that the line angle is the angle seen from the polymer side that is not in contact with the bar.

The material of the bar used in the present invention is a material with high friction resistance and rigidity such as glass, ceramics, metal, or synthetic resin, and particularly preferably strong ceramics such as zirconia ceramics.

Its cross section (that is, the cross section perpendicular to the length direction of the bar) has a shape as shown in FIGS. may have. Further, the number of times the laminate contacts the bar is not limited to one time, but may be multiple times.

The radius of curvature of the corner where the laminate contacts the bar is 0, O
Olmm or more and less than 25I11-, preferably O,
b+m or more and less than 1 mm. Here, when the radius of curvature of the corner where the polymerized laminate contacts the bar is 25s+s or more, when the elongated laminate moves along the bar while maintaining tension, shrinkage plastic deformation hardly occurs, A sufficiently flat laminate cannot be obtained, on the contrary, 0°0011111
If the radius of curvature is less than 1, the laminate may be damaged or cut when it moves along the bar, which is not preferable.

Further, it is preferable that the corners where the bar and the laminate come into contact have linearity in the width and/or height direction with an accuracy within ±lsm. The above-mentioned linearity means that the corner where the laminate and the bar are in contact has linearity with the above-mentioned precision also in the vertical direction and/or the front-back direction. Further, during normal curl correction, the bar tends to be slightly deformed in the flow direction of the laminate due to the tension of the laminate, but the amount of deformation is preferably within ±1 mm.

Further, as illustrated in FIG. 9, the bar may be rotatable. That is, a rotatable or rotating contact portion 51 with a radius of curvature of less than 251111 is provided in the groove ray 52 at the top of the bar. The contact portion may be rotated naturally according to the flow of the laminate, or may be rotated while being controlled from the outside. For example, a piano wire-shaped wire with a highly precise circular cross section is pulled at both ends and brought into contact with the laminate while being rotated in a groove by an external drive under tension. The rotation can be selected within a range in which the circumferential speed is equal to or less than the passing speed of the laminate and close to a stationary state. In addition, as shown in FIG. 10, guide rolls 62 and 64 are provided in parallel and close to the corners of the bar.
It is also possible to press the laminate from the side of the curled inner layer immediately before and/or immediately after passing the bar. Further, the rotation of this guide roll may be controlled and the distance between the guide and the bar may be adjusted.

In addition, the bar can be adjusted to 5011 by the attached vibration adding means.
It is also a preferable embodiment to vibrate with a frequency of z or more and an amplitude of 0.001 mm or more and 1 mm or less.

The direction of this vibration is arbitrary with respect to the laminate.

Vibration of the bar is given by a suitable number of vibrators fixed to or in contact with the base of the bar or other suitable positions. That is, the bar is vibrated by providing 1i'll11 wire rings on one side, both sides, or other positions of the bar depending on the material of the bar.

In the present invention, the 'folding angle' means, as mentioned above,
a surface of the elongated polymer laminate introduced into the bar;
This refers to the angle formed by the plane of the product that comes into contact with the bar and is guided to move. The angle is not particularly limited, but is preferably about 20 to 179 degrees. Generally, if the angle is less than 20 degrees, there will be large frictional resistance and resistance due to bending rigidity when the laminate moves on the bar, and there will be problems with the three-dimensional arrangement of the device, making it difficult to move the laminate smoothly. If the angle is greater than 179 degrees, the contact distance of the laminate with the bar is small, and the deformation stress that the laminate receives becomes very small, making it difficult to straighten the curl of the laminate as desired.

Further, the contact between the laminate and the curved surfaces of the first bar and the second bar is performed while maintaining the tension state. Maintaining such tension can be carried out by devices known per se, which tension the elongated polymer laminate. Suitable tension ranges vary depending on the degree of curl of the laminate, the material and thickness of each polymer, and the radius of curvature of the bar, but are usually greater than 50 gr per cm of width of the polymer laminate, preferably 200 to 2000 gr. selected from the range. When the tension applied to the laminate is less than 50 gr/cm, when the laminate moves on the bar due to the bending rigidity of the laminate, the length that the laminate moves along the curved surface of the bar is extremely short, resulting in The radius of curvature of the curved surface drawn by the laminate on the bar becomes large, making it difficult to achieve the effects of the present invention, and
If it exceeds m, all the polymer layers will undergo stretching plastic deformation due to the tension, which will have an adverse effect on curl correction. The tension can be applied by increasing or decreasing the torque of a device that drives the take-up roll, such as an electric motor, or by providing a take-up roll in front of the take-up roll.
It is given by controlling this driving torque.

In the present invention, the speed at which the elongated polymer laminate is moved on the curved surface of the bar is not particularly limited, but is preferably 0.2 to 10 n/min in practical terms.

Curl correction in the present invention is preferably carried out at a temperature below the glass transition temperature of the polymer with the lowest glass transition temperature; however, if curl correction is performed at a high temperature, the laminate will be Since curls often start again due to temperature changes, the preferred temperature range is 10-50°Cf.
1 degree, and when the method of the present invention is carried out in this manner, the re-occurrence of curl due to subsequent temperature changes will be negligible.

In addition, in the movement of the laminate to the first and second bars of the present invention, the means for moving the laminate to the first and second bars is not particularly limited, and if the laminate deviates from the advancing line, the controller for correcting the line may be used. Various methods can be selected and used as appropriate.

In addition, when curing is performed as desired in the present invention, the glass transition temperature of the polymer having the lowest glass transition temperature must be 10°
It is preferable to conduct the heating at a temperature lower than C or more for about 10 minutes or more.

According to the curl correction method of the present invention, curls occurring in a long polymer laminate are substantially eliminated. The present invention also provides a method for causing shrinkage plastic deformation in at least a portion of a polymer laminate in which two or more polymer layers are laminated and curled, which is obtained by the curl straightening method as described above, for example. , a polymer laminate in which the radius of curvature of the curl is 10 cm or more.

It goes without saying that the present invention is not limited to a polymer laminate having a two-layer structure, but can be similarly applied to a polymer laminate having three or more layers and a maximum of ten layers.

[Industrial applicability]

According to the method of the invention, curled polymer laminates can be easily straightened.

In addition, the curl-corrected polymer laminate obtained in the present invention can be used for insulating materials, coverlays for flexible printed wiring boards, packaging materials, etc., and compared to curl-corrected polymer laminates. It has the effect of being extremely easy to handle, and it cannot but be said that its industrial applicability is extremely large.

〔Example〕

Next, examples will be shown to illustrate preferred embodiments of the present invention.
An example of this will be further explained.

Example 1 14.6 g (0.05 mol) of 1,3-bis(3-aminophenoxy)benzophenone and 92.1 g of N,N-dimethylacetamide are placed in a container equipped with a stirrer, a reflux condenser, and a nitrogen inlet tube. 3. Insert and incubate under nitrogen atmosphere at room temperature.
16.1 g (0.05 mol) of 3',4,4'-henzuphenonetetracarboxylic dianhydride was added in 4 portions while paying attention to the increase in the dissolved Mi by 11 degrees, and the mixture was stirred at room temperature for about 20 hours. . Logarithmic viscosity (N,
N-dimethylacetamide solvent, concentration 0.5 g/10 (
11 solvent, measured at 35°C) was 1.23 dl/g. This polyamic acid solution was diluted with N,N-dimethylacetamide to a rotational viscosity of 10.0OOc.
Adjusted to ps.

The amic acid thus obtained was uniformly cast onto a commercially available polyimide film "Avical" (manufactured by Hitomiga Kagaku Co., Ltd.) 25 μm, and dried by heating at 100°C, 200°C, and 1300°C for 10 minutes each. A polymer laminate consisting of two layers of polyimide was obtained. The thickness of this laminate was 35 microns. In addition, when we examined the state of curls using this laminate as a 24cm x 24cm square film, we found that curls were formed with the ``avikal'' on the outside in both the longitudinal and width directions, and the radius of curvature of each curl was 1.5cm.
Met.

The polymer laminate thus obtained was slit to a width of 24 cm using a slitter, and wound onto a take-up roll.

Thereafter, the polymer laminate was moved and fixed with a first glass bar (see Figure 6) at an angle (line angle) of 45 degrees, i.e. α, -45 degrees to the width direction of the polymer laminate. The cross section is 20mm wide and 100m5+ long.
The avical film was folded at a folding angle of 80 degrees, with the avical film side touching the corner (the radius of curvature of one corner was 0.3 mm) of the rectangular shape. After this, the second bar (see Figure 6, -4
It is fixed at an angle (line angle) of 5 degrees or α2 - 45 degrees, and the cross section has a width of 20 mm and a length of 10 mm.
The film was folded back at a folding angle of 80 degrees, with the avical film side touching the corner (the radius of curvature of one corner was 0.3 cm) of the rectangle (having a rectangular shape of 0 mm). At this time, the long polymer laminate weighs 24 kg (i.e. 1.0 kg).
The polymeric laminate was moved while applying a tension of (g/cm ). These operations were carried out at room temperature, and the moving speed of the polymer laminate was 1.0 m and 7 minutes.The operations of 0 or more were repeated twice. Thereafter, the polymer laminate is rolled up for 10 minutes.
It was placed in a dryer at 0°C, cured for 10 minutes, and then cooled.

The polymer laminate obtained by the above procedure is 24cm x 24cm.
In the case of a c# square film, the state of curl was visually inspected, but almost no curl was observed.

In addition, the polymer laminate before the curl straightening operation was
, a polyimide film (hereinafter abbreviated as PI-A) was immersed in a solution of chlorophenol:phenol 9:1.
was removed and dried to leave only the avical film, and the PI-
When measuring the dimensions before and after removing A, it was found that it had grown by 0.3%. On the other hand, when a polymer laminate that had been subjected to a curl straightening operation was similarly examined after removing PI-A, it was found that the elongation of the avical film was 0.1%. For this reason, by implementing the curl straightening method of the present invention, the avical film can be reduced to 0.3% - 0.1% = 0.2%.
It was confirmed that the specimen was undergoing shrinkage plastic deformation.

Similar measurements were made on the PT-A film, and it was found that the PI-A film was 0.6 before curl correction.
%, and after correction, it had shrunk by 0.2%. That is, it was revealed that the PI-film was subjected to stretching plastic deformation of 0.6%-0.2%/0.4% due to the curl straightening operation.

Example 2 A commercially available polymeric laminate, Kapton F (manufactured by DuPont Azuma, consisting of 12.5 μm of polytetrafluoroethylene formed on a 25 μm polyimide film), was used in a 24-cm film.
When we examined the curl condition of a square film of s x 24 cm, we found that curls were formed with the polyimide on the outside in both the longitudinal and width directions, and the radius of curvature of the curl was 1 cm.
) with the first bar made of glass (see Figure 6, at an angle of 45 degrees or α1 = 40 degrees with respect to the width direction of the polymer laminate (
line angle), and the cross section has a width of 20
It was folded back at a folding angle of 100 degrees, with the polyimide side touching the corner (the radius of curvature of one corner was 0.2 mm) of a rectangular shape with a length of 100 mm. After this, the second bar (see Fig. 6, fixed at an angle (line angle) of -45 degrees to the width direction of the polymer laminate, that is, αt = -50 degrees, and has a cross section with a width of 20 mm and a long length). It was folded back at a folding angle of 100 degrees, with the polyimide side in contact with the corner (the radius of curvature of one corner was 0.2 mm) of a rectangular shape with a length of 100 o+m. At this time, 19.2
The polymeric laminate was moved under a tension of 1.2 kg (or 0.8 kg/cm). These operations were performed at room temperature, and the polymer laminate movement rate was 1.0 g+/min. The above operation was repeated twice.

The polymer laminate obtained by the above procedure was 24cs x 24
When the film was made into a square cm square film, the curl condition was examined and the radius of curvature of the curl was 16 c+a in both the width direction and the longitudinal direction, and the curl condition could be called flat.

Here, in the same manner as in Example 1, the degree of stretching and shrinkage of each layer of the polymer laminate before and after curl correction was examined. The elongation of the polyimide film decreased from 0.4% to 0.1% before straightening, and was subjected to shrinkage plastic deformation of 0.3%. On the other hand, the shrinkage of polytetrafluoroethylene decreased from 0.6% to 0.2%, and it was confirmed that the polytetrafluoroethylene had undergone stretch plastic deformation of 0.4%.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a state in which the polymer laminate is curled, FIG. 2 is a schematic diagram showing the folding angle, and FIGS. FIG. 7 is a cross-sectional view showing the shape of the bar, and FIG. 8 is a cross-sectional view showing the contact state between the bar and the polymer laminate. FIG. 9 is a perspective view showing a rotatable bar, and FIG. 1O is a
It is a schematic diagram showing a guide roll. Patent applicant Mitsui Toatsu Chemical Co., Ltd. Figure 2 Figure 5 Figure 6 Figure 7 (a) (b) (C) (d)
(e) (f) (8) (h) (i)
Figure 8 Figure 9

Claims (5)

[Claims] (1) A polymer laminate in which two or more layers of polymers are laminated and a part of the curled polymer laminate is subjected to shrinkage plastic deformation so that the radius of curvature of the curl is 10 cm or more. (2) A curled polymer laminate with a radius of curvature of 0.0 at an angle of 0 to 80 degrees with respect to its width direction.
01 or more and less than 25 mm on the curved surface of the first bar, the step of sliding it in the longitudinal direction in a tensioned state with the curled outer side inside, provided at an angle of 0 to -80 degrees with respect to the width direction. , the step of sliding the laminate under tension in the longitudinal direction on the curved surface of a bar with a radius of curvature of 0.001 or more and less than 25 mm with the curled outside facing inwards, is carried out one or more times. A method for straightening curls in a polymer laminate, characterized by: (3) The method according to claim 2, wherein in each step, the folding angle between the plane to which the laminate introduced into the bar belongs and the laminate extracted from the bar is from 20 degrees to 179 degrees. (4) The method according to claim 2, wherein the tension state in each step is 20 g/cm or more as a tension applied to the laminate, and the temperature of the laminate is below the glass transition temperature of the polymer. . (5) The method according to claim 2, wherein after the final step is completed, the laminate is cured for 10 minutes or more at a temperature that is 10° C. or more lower than the glass transition temperature of the polymer.