JPS6036373B2 - Manufacturing method of copolymerized polyamide film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a crystalline copolyamide film, and is particularly effective as a method for producing a low crystalline copolyamide film.

Copolymerized polyamides are expected to be used for various purposes due to their functions. For example, applications include thermal (hot melt) adhesive materials, photosensitive resins, thermally sensitive electrical materials, and electrical information recording materials. In such applications, the copolyamide can be used in the form of powder, solution or dispersion in a solvent, or film, and films are preferably used from the standpoint of simplifying and rationalizing higher-order processing steps. Copolymerized polyamide films are generally molded using an extruder.

This is a method in which the resin is melted in an extruder, extruded through a die, and then cooled and solidified. However, the extruded film of copolymerized polyamide film is extremely sticky and has a fatal problem in terms of manufacturing stability.
With conventional film forming methods, it is difficult to produce films due to adhesion to the roll of the film-forming equipment and blocking during winding.When making a single-layer copolyamide film, it is necessary to surface-treat the roll of the film-forming equipment. Even if adhesion of the resin is avoided, blocking during winding is significant, and after winding, the films may coalesce together, resulting in resin clumps that are difficult to separate. To solve this problem, copolyamides have traditionally been produced by extrusion lamination, in which they are melt-extruded onto paper coated with a template agent such as silicone resin on both sides and then rolled up. There are problems and improvements are desired. [11 If you want to use the copolymerized polyamide film as a single layer, separate the film from the release paper and roll it up into a roll. However, even if you carefully roll up the scale paper, it will meander in the middle, so the release paper should be reused. However, the production cost of the film is high.

'2' In order to smoothly extrude the copolyamide onto the release paper, it is necessary to combine the template paper 4 and the copolyamide with the cooling roll 3 and press roll 2 and take it off, as shown in FIG.

However, the molten copolyamide sticks to the cooling roll 3, making it difficult to work smoothly. If template paper is also used on the side of the cooling roll 3, the cooling capacity will decrease, productivity will deteriorate, and manufacturing costs will further increase, making it impractical. In addition, as shown in Fig. 2, a template paper 4 is placed on the side of the cooling roll 3, and on the side of the press roll 2, water is applied to the press roll 2 using a water tank 8 and a water pickup roll 7 to prevent the copolyamide from sticking. There is a method to do this, but cooling is done through template paper, which limits the cooling capacity, slows down production, and increases manufacturing costs.

Furthermore, there is a problem that the functionality in practical use deteriorates due to water absorption of the copolyamide. If the press roll 2 is not used, this problem can be solved, but the adhesion to the template paper will be incomplete, making it difficult to produce a film with good flatness. paste
Since the extrusion lamination method involves single-layer extrusion, it is difficult to obtain a thin film of good quality, and for example, the thickness of the film becomes non-uniform.

When the thickness is less than 50 mm, it is very difficult to obtain a film with good thickness uniformity. The thickness of the film plays an important role in expressing various functions in each application. In electrical and adhesive applications, films with a thickness of 50 mm or less are often required for functional control. For example, when used as an adhesive film for clothing, it may not be possible to use a thick film due to texture control. The use of films with uneven thickness in textile applications can lead to uneven texture and performance defects. ■ Even if it is attempted to use a plastic film instead of release paper, the melt extrusion temperature of copolyamide is higher than that of general resins, which limits the practical use of the film due to heat shrinkage and melting.

Although it is not impossible to form a single-layer copolyamide film if the following conditions are met, it is difficult to realize because it causes a decrease in functionality and requires a high cost to produce the film.

It is possible to prevent adhesion by blending lubricants, anti-booking agents, polymers, etc., but in order to obtain a sufficient effect with a single layer of copolymerized polyamide film, at least 5 to 3
It is necessary to add approximately % by volume. If such an amount is added, the original function of the copolyamide will be lost. For example, thermal adhesion and heat-sensitive electrical properties almost disappear. Another possible method is to moderately promote crystallization during the film forming process. For example, as shown in FIG. 3, a water tank cooling method is employed in which the extruded film is introduced into a water tank 8, and a heat treatment zone 9 is provided between steps up to winding to promote crystallization. However, even if the temperature and humidity conditions are adjusted to obtain the highest crystallization rate, some copolyamides require a processing time of at least 1 minute or more. It is desired that the economical production speed of plastic film be at least 1 h/min or higher, but in order to produce this copolyamide film at such a speed, the length of the heat treatment zone would need to be 10 h/min or more, making it impossible to implement. It is. For direct composite film formation, there are two methods: a method for forming a composite film of polyamide and different resins, a method of simultaneously extruding an adhesive resin and a different type of resin with extremely low adhesion using a multilayer die, or a composite film produced in this way. Methods have already been proposed in which adhesive films can be peeled off and reused. However, such conventional methods differ in content or effect from the present invention in the following points. m The present invention aims to achieve both excellent film quality and retention of the excellent functions of the copolyamide by forming a composite film of a crystalline copolyamide and a different resin and controlling the transition of crystallinity. It is something.

Conventional methods do not control the transition of crystallinity, so even if sticking during the film forming process is avoided, the excellent performance of copolyamides cannot be exhibited in practical use. The method of directly compounding adhesive resin with non-adhesive resin often does not allow smooth adhesion of both film layers after composite extrusion, and even uses press rolls and pressure molding. is the actual situation. Although the double-pressure molding method uses a non-adhesive resin on one side to prevent adhesion during the film-forming process, in the case of two layers, the adhesive resin always comes into contact with the roll at the fall-pressure molding roll, making it useless. It is the meaning. In the present invention, since coalescence and adhesion with different resins are smoothly achieved by controlling the degree of crystallinity, a press roll is not required and there is no such problem. {2) Although there are many proposals regarding composite membrane formation of polyamide and different resins such as polyolefin, none have addressed the crystalline copolymerized polyamide of the present invention.

The present invention can improve the problems in manufacturing English polymerized polyamide films that could not be solved by conventional methods, namely poor productivity due to resin adhesion and high manufacturing costs due to countermeasures. Furthermore, an easy-to-handle film without surface tackiness can be obtained without deteriorating the various functions of the copolyamide. Another feature of the present invention is that a prey film with good thickness uniformity can be produced. Furthermore, depending on the settings of the resins to be directly composited, it is possible to produce a copolymerized polyamide film having new functions not previously seen, as will be described later. In the present invention, the latent heat of crystal melting of the copolyamide is 1. After the copolyamide and other resins other than the copolyamide are directly composited to form a film, the latent heat of crystal fusion of the copolyamide is 1. &al/ta or more. Note that the latent heat of crystal fusion can be measured using a differential scanning calorimeter or the like. Polyamide is a dimeric fatty acid (
Dimer fatty acids) and diamines or modified polyamide resins obtained by condensation polymerization using dimeric fatty acids and polyalkylene polyamines as main raw materials, diamines and dicarboxylic acids, condensation polymerization of amino acids, ring-opening polymerization of lactams, etc. Super polyamide resins are broadly classified into so-called nylons. The English-polymerized polyamide of the present invention is particularly effective for the latter type of nylon, and is preferably used because it has excellent functions such as adhesion and electrical properties, and because its crystallization behavior can be effectively utilized. The copolyamide used in the present invention is a crystalline copolymerized nylon, and is a low crystalline material with a degree of crystallinity of 20% or less.

Such a copolyamide can be polymerized by mixing two or more types of homonylon raw materials. For example, the raw materials include the following. Nylon 6, nylon 66, nylon 610
, nylon salt or lactam, raw material for nylon 11 and nylon 12. Salts obtained from the following diamines and dicarboxylic acids (e.g. adipic acid, sebacic acid), bis(4-aminodichlorohexyl)methane, metaxylylenediamine or its hydride, piperazine, 2,5-dimethylpiverazine, trimethylhexane Examples include methylene diamine. Examples of the copolyamide used in the present invention include the following.

Nylon 6/66/610 copolymer, nylon 6/12
copolymer, nylon 6/66/IZ copolymer, nylon 6/66/610/12 copolymer, Nylon.

Nylon 6/69 copolymer, Nylon 12/612 copolymer,
Nylon 6/66/11 copolymer, nylon 6/66/
612 copolymer, etc., and examples of those preferably used include the following polymer composition. Nylon 6/6
6/610/12 copolymer (20-60% by weight/5-4
5 wt%/10-5 wt%/2-45 wt%), nylon 6/66/12 copolymer (15-55 wt%/10
~50wt%/25-70wt%), nylon 6/12
copolymer (10-40% by weight/65-90% by weight), nylon 6/6 copolymer (40-80% by weight/20-6
), nylon 6/66/610 copolymer (20
~6 wt%/10~5 wt%/10~4 wt%)
.

The latent heat of crystal fusion at saturation during crystallization treatment is desirably 3 cal/ta or more, preferably 5 cal/ta or more, in order to achieve both non-adhesion during handling and various functions of the copolymerized polyamide. Note that other copolymerizable monomers may be introduced into the copolyamide, or different resins or additives may be mixed within the range that does not impair the original function. In the present invention, the resin to be directly composited with the copolyamide is a melt-extrudable resin other than the copolyamide, and must have melt characteristics such as melt viscosity and extrusion temperature that can be smoothly composited with the copolyamide.

Furthermore, the resin layer must eventually peel off and must not permanently adhere to the copolyamide. Although the composition of the resin is not particularly limited, for example, the following can be used, and an appropriate one is selected depending on the use of the copolyamide. Polyolefins are often preferred. Examples of polyolefins include polyethylene, polypropylene, propylene-ethylene copolymers, methylbentene copolymers, such as poly-4-methylbentene-1, polyisoptylene, polyisobrene, polybutadiene, and poly-1-octene. In addition, modified polyolefins may be copolymerized with one or more of English polymer monomers such as alkyl acrylate, tacrylic acid, maleic anhydride, itaconic acid, and vinyl acetate. Ethylene copolymer with metal ion bonds, so-called ionomer. Saponified product of ethylene-vinyl acetate copolymer. Also included are polyesters such as polyethylene terephthalate and polybutylene terephthalate. When a polyolefin such as polypropylene or poly4-methylbentene-1 is used as the resin to be directly composited with the copolyamide, alkyl acrylate, methacrylic acid, maleic anhydride, itaconic acid, vinyl acetate, etc. may be copolymerized in the copolyamide. Modified polyolefin or copolymerized polyolefin (including ethylene copolymer) obtained by copolymerizing one or more types of monomers
When an ionomer, an ethylene copolymer containing metal ion bonds and metal ion bonds, is added, the two layers have good affinity and work smoothly during the process of forming a composite film, and the copolyamide is crystallized and the two layers are separated. After this, the resin added to the copolyamide may improve the slipperiness and blocking property of the surface of the copolyamide film, resulting in favorable effects. For direct composite production of copolyamide and different resins, there are methods such as using multiple extruders and performing the composite within the polymer tube from the extruder cylinder to the die, within the die, or immediately after discharge from the die. The latent heat of crystal fusion of the copolyamide should not exceed 1.0 cal' until the composite film is rolled up and film formation is completed. For this reason, special attention must be paid to the temperature and water absorption conditions during cooling and solidification (casting) and the process up to winding up. An example of preferable film forming conditions is to prevent the temperature of the copolyamide from rising above the glass transition temperature from casting to winding of the film, or to suppress the temperature within several minutes even if it rises above the glass transition temperature. . Furthermore, since crystallization of crystalline copolyamide is promoted by water absorption, a cooling method of immersing it in a water bath after extrusion is not preferred.
By suppressing crystallization during the film forming process, it is possible to obtain sufficient adhesion with different resins to be directly composited, and it is a non-adhesive type.
It is possible to prevent peeling between film layers during the film forming process, which is a major problem in the film forming industry of composite films. When each composite film is isolated to obtain a single film roll of copolyamide, if there are partial peel voids, the peel adhesion strength becomes uneven, causing fluctuations in peel tension and causing partial deformation of the copolyamide. This causes film flatness defects such as wrinkles and sagging. Another feature of the present invention is that a thin copolyamide film can be obtained by the method of the present invention. By increasing the ratio of the thickness of different resins, it is possible to make a thin film of English polymerized polyamide, and the adhesion with the different resins is good, making the film forming work easier. For example, it is possible to produce a film with a size of about 10 to 20 F, which could not be obtained by conventional methods. A direct composite film that is formed so that the latent heat of crystal fusion does not exceed 1.0 cal/t is made such that the latent heat of crystal fusion of the copolyamide is 1.5 cal/t or more, preferably 3 cal/t, before being used for each purpose. Crystallize as above.

Crystallization of copolyamide is affected by temperature and humidity. In order to obtain the desired degree of crystallinity in a short time, conditions may be set to achieve the highest crystallization rate, and there are conditions for obtaining the maximum temperature between the glass transition temperature and the melting point. When the temperature is below the glass transition temperature and in a low temperature atmosphere, crystallization hardly progresses and it may even take several months to achieve the desired degree of crystallinity. Glass transition temperature is 30-40qo
There is also a copolymerized polyamide, and in order to form a film and crystallize it, the goal cannot be achieved if it is left indoors, and a heating chamber is required. Although it is possible to make the copolyamide absorb water and promote crystallization by leaving it in a high-temperature atmosphere or by sprinkling water on it, excessive water absorption is not preferable because it deteriorates various functions in various uses. In addition, if water absorption is uneven, dimensional changes will be uneven, causing wrinkles and sagging of the film, resulting in poor flatness. Unless the latent heat of crystal fusion of the copolyamide is 1.5 cal/ta or more, the copolyamide has poor adhesion and slipperiness and cannot be put to practical use. For example, the following problems arise. {1} When a copolymerized polyamide is isolated from a composite film to produce a roll of a single layer film, the adhesion with the different resin film is significant and the peeling operation cannot be performed smoothly. Also, because the peeling force is strong, the copolyamide film tends to deform, causing wrinkles and sagging. Even if the film is wound into a roll, flocking occurs between the films, which poses a problem when the film is unwound. If the crystallization is insufficient as described above, it is not possible to produce a copolyamide film with good film quality. ■ Copolyamide films are used in various applications such as thermal adhesive materials, photosensitive resins, thermally sensitive electrical materials, and electrical information recording materials, either in the form of composites with different resins or in the form of separated single-layer films. , is often used in combination with various types of Motomura.

For example, in the case of thermal bonding, it is heat-pressed to fiber cloth or metal plates,
In the case of heat-sensitive electrical materials, they are heat-pressed and bonded to a conductor. Since this operation is carried out continuously by transporting the copolyamide film on a roll as it is rolled out, the English polymer polyamide is required not only to be non-adhesive but also to have a low coefficient of friction. If crystallization is insufficient, the adhesion and coefficient of friction will be high, making it impossible to perform smooth bonding and composite work. In the present invention, the film roll rolled up at the final point of the direct composite film forming process is preferably left for 5 to 20 hours or more after winding, and then the composite film is unrolled and all subsequent operations are performed. It was found that the properties were further improved.

The subsequent operations include, for example, unwinding of the composite film,
Slitting the composite film, separating the different resin film and copolyamide film, thermally bonding the copolyamide side of the composite film of different resin and copolyamide to metal or fiber material, and completing the work. This includes work to separate different types of resin films. In the present invention, each layer of copolyamide or different resin may be composed of a plurality of different layers, if necessary. The crystalline copolyamide film obtained according to the present invention can be applied to the following uses.

tl} Teaching material Crystalline copolymerized polyamide film produced according to the present invention, for example, crystalline nylon 6/66/610 copolymer,
Nylon 6/66/12 copolymer, nylon 6/66/
610/12 copolymer film can be applied to fibers, metals, wood,
It is useful as an adhesive for various materials such as leather, glass, and polymer molded products.

At room temperature, it has no tackiness, has excellent slipperiness, and is easy to handle, and can be thermally bonded at relatively low temperatures, for example, from about 10,000 degrees, making it useful as an adhesive film for heat-pressing. It is particularly suitable for bonding substrates that are easily altered by heat, such as fibers and leather. Heat pressing methods include heat press, high frequency press,
Ultrasonic presses are available. According to the present invention, new functions can be developed by selecting different types of resins to be directly combined. For example, if a different resin having a softening temperature higher than that of copolyamide is used, it will function as a release film that can withstand heat and pressure bonding. If a transparent material is used even after extrusion, it is easy to confirm the positioning of the base material and the thermal adhesive film, and to confirm the quality of the thermal adhesive. Preferred resins that meet this purpose include polypropylene and methylbentene polymers such as 4-methylbentene-1. In order to obtain excellent thermal bonding strength, the thermal bonding temperature of English polymerized polyamide may rise up to 200 qo, but when used as a composite film, 4-methylbentene-1 polymer can withstand use at this temperature and is preferably used. be done. The present invention further has the following features. When a composite film of copolyamide is thermally bonded to a base material and then the base material is molded, the release film can also be molded to follow the curved surface, a performance that cannot be achieved with template paper. If the curved surfaces of the base materials to be laminated are processed separately and then laminated and bonded, if a copolymerized polyamide composite film is attached at the time of molding the curved surface of either base material, the different resin will act as a protective film during transportation of the base materials. Prevent damage to the thermal adhesive layer. For example, adhesion of molded ceiling materials (insulating and sound-absorbing materials covering interior materials) to automobile roofs (metal), manufacturing of convex or concave mirrors, and affixing copolymerized polyamide to either the support or the mirror surface material. After fitting and molding, both base plates are heat-pressed and combined. [21 Electrical material copolymerized polyamide has the characteristic that impedance characteristics change depending on the ambient temperature, and can be used as a switch element.

The copolyamide film formed into a film is used for heat-sensitive materials such as planar heating elements. [3] Photosensitive resin polymerized polyamide If a film is formed according to the present invention by adding a photopolymerizable or photocrosslinkable substance that is stable to the heat of extrusion and exhibits a photoinsoluble property, a photosensitive polymerized polyamide can be produced. Film can be manufactured.

It can be used in so-called photoresist dry films used in the production of printed circuits and metal parts. Example 1 Crystalline polyamide copolymer (nylon 6/66/610/12 copolymer (4
0 wt%/2 wt%/25 wt%/15 wt%) and isotactic polypropylene are copolymerized by direct compounding method in a die using two extruders, polyamide, thickness 2
A film was formed using polypropylene with a thickness of 30 mm and a thickness of 30 mm.

As shown in FIG. 4, a casting method using a cooling drum 3 was employed, and the polypropylene was extruded so as to touch the drum. Water at 230C is circulated through the drum, and the temperature of the film is between 25 and 270 when it leaves the cooling drum.
Met. The temperature of the winding roll is also within this range. The copolyamide part was taken out from the film immediately after being rolled up, and the latent heat of crystal fusion was measured using a differential scanning calorimeter.
I got the value of l/evening. During film production, the work could be carried out smoothly, with no peeling between the composite films or partial entrapment of air. Two types of composite films were made, one in which the composite film was left in an atmosphere at 5° C. for 3 hours and the other in which it was left in an atmosphere for 4 hours. The latent heat of crystal fusion of the treated product was measured, and the product treated for 3 hours was 3 cal/night,
4 different time processed products achieved a value of 9 cal/night. Separation of the copolymerized polyamide film and polypropylene film was carried out for each treated product. There was no resistance during peeling, and the copolyamide film could be rolled up smoothly without deformation. Further, even when the film was left in a roll after being rolled up, blocking did not occur. Copolymerized polyamide film was used for thermal bonding of metal strips and urethane foam sheets.
All materials for lamination were supplied in rolls and continuously heated and pressed while being pulled out, but the copolyamide film had good slipperiness and the work could be carried out smoothly.
The slipperiness of the product treated for 4 anchor hours was better than that of the product treated for 3 hours, and the latter had better workability when working at high speeds.
In addition, when we conducted a test in which the winding roll on which the composite film was formed was left as it was in a film forming chamber (room temperature: 10°C, relative humidity: 60-70%), the latent heat of crystal fusion of the copolyamide remained unchanged even after one week had passed. 0. It was evening. The adhesion of the copolyamide was so great that it could not even be separated from the polypropylene film. **Example 2 Crystalline nylon 6/66/12 copolymer (wt% of 3/2
(wt%/5wt%) and 4-methylbentene-1 polymer were combined in a die in the same manner as in Example 1 to form a film.

The extrusion temperature is 260°C. The temperature conditions after extrusion were controlled in the same manner as in Example 1, and the product was rolled up. The latent heat of crystal fusion after winding was 0.2 cal. As in Example 1, the composite film had good adhesion and could be formed smoothly. The composite film was left in an atmosphere of 50q○ for 4 hours. The latent heat of crystal fusion of the treated product was 11 cal'. The composite film was used for adhering patches to textile fabrics. Place a hot plate on the 4-methylbentene-1 polymer side so that the copolyamide adheres to the patch side with the composite film intact.
Thermocompression bonding was carried out at 0°C. The work went smoothly without any problems with the resin adhering to the hot plate. Furthermore, during the thermocompression bonding process, there was no thermal shrinkage or deformation of the 4-methylbentene-1 polymer film. The 4-methylbentene-1 polymer film was removed from the patch to which the composite film was attached, but it was easily peeled off.
Subsequently, the patch was thermally bonded to a fiber fabric, and the workability was good. Example 3 In the same manner as in Example 1, a composite film was formed using a different copolyamide polyamide.

The comparisons of crystallinity, latent heat of crystal fusion, and film-forming workability are shown in the table below, and it is clear that the method of the present invention requires that the crystallinity of the copolyamide used is 20% or less. It shows. *1 Same as the nylon copolymer shown in Example 1 *2 Measured value immediately after composite film formation and winding *3 50
Measured value after 3 hours of treatment at
qo) By cooling and solidifying the polypropylene film and leaving it in that state, it is possible to confirm that there is sufficient adhesion between the polypropylene film and the layer, but in actual production it is difficult to adjust the thickness (thickness measurement) under such conditions. However, it cannot be put to practical use for reasons such as the inability to carry out the process, that is, it can only be put to practical use by using a copolyamide with a crystallinity of 20% or less.

Similarly, nylon 6/6 year copolymer (95% by weight/5% by weight) has sufficient adhesion between film layers if it is immersed in cooling water (5°C) immediately after composite film formation, but moisture When removed and returned to room temperature, it exhibits values and behavior close to the latent heat of crystal fusion as shown in the table above.

In contrast, nylon 6/66 copolymer (wt% of 6/
4) can be carried out without any trouble until winding. Example 4 A composite film of the following copolyamide was formed in the same manner as in Example 1, and the resulting film was heat-treated at 50 CO for 48 hours.

This result is shown in the following table, and even if the crystallinity of the copolyamide used is 20% or less, the final latent heat of crystal fusion is 1.5.
This shows that the object of the present invention cannot be achieved unless the value exceeds cal'. *1 61: Hexamethylenediamine-isophthalate *2 Measured value immediately after composite imitation winding *3 Measured value after processing at 50°C for 3 hours

[Brief explanation of the drawing]

1 to 3 are schematic diagrams for explaining a conventional extrusion molding method for a copolyamide film, and FIG. 4 is a schematic diagram showing an example of an embodiment of the present invention. In the figure, 1 is an extruder die, 2 is a press roll, 3 is a cooling roll, 4 is a release paper, 5 is a guide roll, 6 is a winding roll, 7 is a water pickup roll, 8 is a water tank, 9 is a heat treatment furnace, 10 is an extruder for copolyamide, and 11 is an extruder for different resins. lFigure 2Figure S Figure Aspirational

Claims (1)

[Claims] 1 The latent heat of crystal fusion of copolyamide is 1.0 cal/
The latent heat of crystal fusion of the copolyamide is 1.5 cal/g or more after forming a film by directly composite a low-crystalline copolyamide with a crystallinity of 20% or less and other resins other than the copolyamide so as not to exceed g. 1. A method for producing a crystalline copolymerized polyamide film which has good peelability from a bonded mating film and is characterized by being crystallized so as to have the following properties.