JP7135942B2 - Laminated film and molding - Google Patents

Description

TECHNICAL FIELD The present invention relates to laminated films and molded articles.

Members of industrial products are made of various materials such as metals, resins, and ceramics. Conventionally, these members are formed in a desired shape in advance and then joined by joining members such as adhesives using curable resins, screws, and rivets (see, for example, Patent Document 1).

JP 2008-111536 A

As a method for joining members of industrial products, there is a demand for the development of a new method that does not require the use of conventional adhesives, screws, rivets, and the like.

A main object of the present invention is to provide a laminated film capable of suitably bonding two or more members. More specifically, the main object is to provide a laminated film having a good appearance after bonding two or more members. Another object of the present invention is to provide a molded article using the laminated film.

Another object of the present invention is to provide a novel method for manufacturing a molded body in which a resin member and a solid member are joined together. More specifically, it is also an object of the present invention to provide a method for producing a molded article having a good appearance after joining a resin member and a solid member via a laminated film.

The present inventors have made earnest studies to solve the above problems. As a result, a laminated film for joining at least two members (for example, a first member and a second member) by heat welding, comprising at least a first heat-fusible resin layer, a heat-resistant intermediate layer, and a second A laminated film comprising a heat-fusible resin layer and a heat-fusible resin layer in this order has a small heat shrinkage rate in a high-temperature environment during heat-fusification, has a good appearance after bonding, and can suitably bond two or more members. I found what I can do.

In addition, the present inventors have proposed a method for manufacturing a molded body in which a resin member and a solid member are joined, the step of preparing a laminate in which a laminated film is arranged on a solid member; a step of supplying a molten resin to the film-side surface; a step of cooling and solidifying the molten resin to form a resin member; and joining the resin member and the solid member via the laminated film. By using a laminated film comprising at least a first heat-fusible resin layer, a heat-resistant intermediate layer, and a second heat-fusible resin layer in this order, a resin member and a solid member are formed. However, the inventors have also found that a molded article can be obtained that is suitably bonded via the laminated film.

The present invention has been completed through further studies based on the findings described above.

That is, the present invention provides inventions in the following aspects.
Section 1. A laminated film for joining the first member and the second member,
A laminated film comprising at least a first heat-fusible resin layer, a heat-resistant intermediate layer, and a second heat-fusible resin layer in this order.
Section 2. Item 2. The laminate film according to Item 1, wherein the heat shrinkage rate measured under conditions of a test temperature of 200°C and a heating time of 10 seconds is 10% or less.
Item 3. Item 3. The laminated film according to Item 1 or 2, wherein the resin constituting the first heat-fusible resin layer has a polyolefin skeleton.
Section 4. Item 4. The laminated film according to any one of Items 1 to 3, wherein the first heat-fusible resin layer contains a modified polyolefin.
Item 5. Item 5. The laminated film according to any one of items 1 to 4, wherein when the first heat-fusible resin layer is analyzed by infrared spectroscopy, a peak derived from maleic anhydride is detected.
Item 6. Item 6. The laminated film according to any one of Items 1 to 5, wherein the first heat-fusible resin layer contains an adhesive component.
Item 7. A molded body obtained by joining polypropylene having a length of 45 mm, a width of 10 mm, and a thickness of 1.5 mm to aluminum having a length of 45 mm, a width of 10 mm, and a thickness of 1.5 mm through the laminated film, and having a shear strength of 3 MPa or more. Item 7. The laminated film according to any one of items 1 to 6.
Item 8. A laminated film for joining the first member and the second member,
The laminated film comprises at least a first heat-fusible resin layer, a heat-resistant intermediate layer, and a second heat-fusible resin layer in this order,
wherein the first member is a solid member;
A molten resin is supplied to the second heat-fusible resin layer side of the laminated film in a state where the first heat-fusible resin layer of the laminated film is in contact with the first member, and the A laminated film used for joining the first member and the second member via the laminated film as a resin member which is the second member by solidifying molten resin by cooling.
Item 9. A molded article, wherein the first member and the second member are joined via the laminated film according to any one of Items 1 to 8.
Item 10. A method for manufacturing a molded body in which a resin member and a solid member are joined,
preparing a laminate in which a laminate film is disposed on the solid member;
a step of supplying a molten resin to the surface of the laminate on the laminated film side;
a step of cooling and solidifying the molten resin to form the resin member, and joining the resin member and the solid member via the laminated film;
and
A method for producing a molded body, wherein the laminate film comprises at least a first heat-fusible resin layer, a heat-resistant intermediate layer, and a second heat-fusible resin layer in this order.
Item 11. The first heat-fusible resin layer of the laminated film contains an adhesive component,
Item 11. The molded article according to item 10, wherein in the step of preparing the laminate, the laminate is prepared by detachably adhering the first heat-fusible resin layer of the laminate film onto the solid member. Production method.
Item 12. Item 12. The method for producing a compact according to Item 10 or 11, wherein the solid member includes at least one of a metal member and a ceramic member.
Item 13. Item 13. The method for producing a molded article according to any one of items 10 to 12, wherein the laminated film having a heat shrinkage rate of 10% or less measured under conditions of a test temperature of 200° C. and a heating time of 10 seconds is used.
Item 14. Items 10 to 10, wherein the laminate film has a shear strength of 3 MPa or more in a molded product obtained by bonding polypropylene and aluminum having a length of 45 mm, a width of 10 mm, and a thickness of 1.5 mm through the laminate film. 14. A method for producing a molded article according to any one of 13.
Item 15. Item 15. The method for producing a molded article according to any one of Items 10 to 14, wherein the resin constituting the first heat-fusible resin layer has a polyolefin skeleton.
Item 16. Item 16. The method for producing a molded article according to any one of Items 10 to 15, wherein the first heat-fusible resin layer of the laminated film contains a modified polyolefin.
Item 17. Item 17. The method for producing a molded article according to any one of Items 10 to 16, wherein when the first heat-fusible resin layer of the laminated film is analyzed by infrared spectroscopy, a peak derived from maleic anhydride is detected.

ADVANTAGE OF THE INVENTION According to this invention, the laminated|multilayer film which can join two or more members suitably can be provided. Moreover, according to the present invention, it is possible to provide a novel method for manufacturing a molded body in which a resin member and a solid member are joined together. For example, in the present invention, the first heat-fusible resin layer of the laminated film is releasably adhered (temporarily adhered) to a solid member (for example, a resin member, a metal member, a ceramic member, etc.), A molten resin is supplied to the surface of the laminated film on the side of the second heat-fusible resin layer, and the molten resin is solidified by cooling to form a resin member, thereby joining the solid member and the resin member via the laminated film. Furthermore, molding of the molten resin and the solid member and bonding of the resin member and the solid member can be performed in one process. As a result, a molded article in which the resin member obtained by solidifying the molten resin by cooling and the solid member are joined via the laminated film can be preferably obtained. Another object of the present invention is to provide a molded article using the laminated film.

BRIEF DESCRIPTION OF THE DRAWINGS It is schematic-drawing sectional drawing of an example of the laminated|multilayer film of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is schematic-drawing sectional drawing of an example of the laminated|multilayer film of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is schematic-drawing sectional drawing of an example of the laminated|multilayer film of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is schematic-drawing sectional drawing of an example of the laminated|multilayer film of this invention. 1 is a schematic cross-sectional view of an example of a molded article of the present invention; FIG. It is a schematic diagram for demonstrating the measuring method of seal strength. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram for demonstrating an example of the manufacturing method of the molded object of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram for demonstrating an example of the manufacturing method of the molded object of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram for demonstrating an example of the manufacturing method of the molded object of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of an example of a molded article manufactured by the molded article manufacturing method of the present invention; It is a schematic diagram for demonstrating the measuring method of a shear strength. FIG. 2 is a conceptual diagram of probe position change in probe displacement measurement using an atomic force microscope to which a cantilever (probe) with a heating mechanism is attached. FIG. 2 is a schematic diagram showing the position of the surface of the heat-resistant intermediate layer in the cross section of the laminated film where the probe is installed in measuring the amount of displacement of the probe using an atomic force microscope to which a cantilever (probe) with a heating mechanism is attached. FIG. 4 is a perspective view for explaining the main surface of the first heat-fusible resin layer of the laminated film on which the probe is installed in the measurement of the softening point of the first heat-fusible resin layer. 1 is a schematic cross-sectional view of an example of a molded body manufactured by the molded body manufacturing method of the present invention when the first member is a solid member and the second member is a resin member; FIG. FIG. 4 is a schematic diagram for explaining an example of the method for manufacturing a molded body of the present invention, in the case where the first member is a solid member and the second member is a resin member; FIG. 4 is a schematic diagram for explaining an example of the method for manufacturing a molded body of the present invention, in the case where the first member is a solid member and the second member is a resin member; FIG. 4 is a schematic diagram for explaining an example of the method for manufacturing a molded body of the present invention, in the case where the first member is a solid member and the second member is a resin member; 1 is a schematic cross-sectional view of an example of a molded body manufactured by the molded body manufacturing method of the present invention when the first member is a solid member and the second member is a resin member; FIG.

A laminated film of the present invention is a laminated film for bonding a first member and a second member, and the laminated film includes a first heat-fusible resin layer, a heat-resistant intermediate layer, and a second heat-fusible resin layer. and layers in this order. Hereinafter, the laminated film of the present invention, a molded article using the laminated film, and methods for producing these will be described in detail.

In this specification, the numerical range indicated by "-" means "more than" and "less than". For example, the notation of 2 to 15 mm means 2 mm or more and 15 mm or less.

1. Laminated Film The laminated film of the present invention is a laminated film for bonding the first member and the second member. More specifically, the laminated film of the present invention is formed by disposing the laminated film between the first member and the second member and heat-welding the first member and the second member via the laminated film to form the first member. Used for joining a member and a second member. In addition to the first member and the second member, other members may be joined using the laminated film of the present invention. That is, the laminated film of the present invention is a laminated film for joining at least two members by thermal welding. Moreover, the laminated film of the present invention is a laminated film having heat-fusible properties (a heat-fusible laminated film).

For example, as shown in the schematic diagrams of FIGS. 1 to 4, the laminated film 10 of the present invention includes at least a first heat-fusible resin layer 1, a heat-resistant intermediate layer 3, and a second heat-fusible resin layer. 2 in this order. The first heat-fusible resin layer 1 constitutes one side surface of the laminated film 10, and the second heat-fusible resin layer 2 is the opposite side of the laminated film 10 to the first heat-fusible resin layer 1. constitutes the surface of Since the laminated film 10 of the present invention has at least three layers of the first heat-fusible resin layer 1, the heat-resistant intermediate layer 3, and the second heat-fusible resin layer 2, the laminated film 10 is composed of two layers. It has an advantage over film in that curling during molding is suppressed. In addition, since the first heat-fusible resin layer 1 and the second heat-fusible resin layer 2 are provided, the first member and the second member can be satisfactorily bonded.

As a specific example of the laminated structure of the laminated film 10 of the present invention, a laminate comprising a first heat-fusible resin layer 1/a heat-resistant intermediate layer 3/a second heat-fusible resin layer 2 in this order as shown in FIG. Structure: Laminated structure comprising first heat-fusible resin layer 1/heat-resistant intermediate layer 3/thermoplastic resin layer 4/second heat-fusible resin layer 2 in this order as shown in FIG. 2; shown in FIG. Laminated structure comprising a first heat-fusible resin layer 1 / thermoplastic resin layer 4 / heat-resistant intermediate layer 3 / second heat-fusible resin layer 2 in this order; A laminated structure including resin layer 1/thermoplastic resin layer 4/heat-resistant intermediate layer 3/thermoplastic resin layer 4/second heat-fusible resin layer 2 in this order may be used. As will be described later, the first heat-fusible resin layer 1 and the second heat-fusible resin layer 2 may each contain an adhesive component and have adhesiveness. Further, the thermoplastic resin layer 4 may have heat-fusibility like the first heat-fusible resin layer 1 and the second heat-fusible resin layer 2 . Other layers different from these layers may be further laminated on the laminated film of the present invention. For example, although not shown, an adhesion promoter layer, which will be described later, may be provided on one side or both sides of the heat-resistant intermediate layer 3 .

From the viewpoint of low cost and simplification of the manufacturing process, it is preferable to make the laminated film thin. It is preferable to have a three-layer laminated structure in which the second heat-fusible resin layer 2 is provided in this order. In addition, it is preferable to increase the thickness of the laminated film from the viewpoint of conformability to uneven shapes, etc. A thermoplastic resin layer is preferably provided between each layer of the layer 2 . Specifically, as shown in FIG. 2, a four-layer laminate structure comprising first heat-fusible resin layer 1/heat-resistant intermediate layer 3/thermoplastic resin layer 4/second heat-fusible resin layer 2 in this order. a four-layer laminate structure comprising first heat-fusible resin layer 1/thermoplastic resin layer 4/heat-resistant intermediate layer 3/second heat-fusible resin layer 2 in this order as shown in FIG. It has a five-layer laminate structure comprising first heat-fusible resin layer 1/thermoplastic resin layer 4/heat-resistant intermediate layer 3/thermoplastic resin layer 4/second heat-fusible resin layer 2 in this order as shown. preferably. Further, when the first heat-fusible resin layer 1 contains an adhesive component, the first heat-fusible resin layer 1 is laminated on the heat-resistant intermediate layer 3 with the thermoplastic resin layer 4 interposed therebetween. Since the adhesive strength of the laminate film of the present invention can be stabilized, the laminated film of the present invention preferably has a five-layer laminate structure containing an adhesive component on both sides (specifically, the first heat-welding property containing an adhesive component A laminated structure comprising resin layer 1/thermoplastic resin layer 4/heat-resistant intermediate layer 3/thermoplastic resin layer 4/second heat-fusible resin layer 2 containing an adhesive component in this order), or a laminated structure having an adhesive component on one side. Four-layer laminate structure (specifically, first heat-fusible resin layer 1 containing an adhesive component / thermoplastic resin layer 4 / heat-resistant intermediate layer 3 / thermoplastic resin layer 4 / second layer not containing an adhesive component It is preferable to have a laminate configuration in which two heat-fusible resin layers 2 are provided in this order.

From the viewpoint of low cost and suppression of the possibility of delamination, the number of layers in the laminated film of the present invention is preferably as small as possible. From the viewpoint of reducing the heat shrinkage rate in a high temperature environment during heat welding, improving the appearance after heat welding, and suitably heat-welding two or more members, the number of layers of the laminated film of the present invention is , preferably about 3 to 5, more preferably about 3 to 4.

Also, the area of one surface of the laminated film of the present invention can be appropriately set according to the size of the member to be thermally welded.

From the viewpoint of reducing the heat shrinkage rate in a high-temperature environment during heat welding, improving the appearance after heat welding, and more preferably heat-welding two or more members, the laminated film of the present invention is tested at a test temperature of 200. The upper limit of the thermal shrinkage measured under the conditions of ° C. and a heating time of 10 seconds is preferably about 10% or less, more preferably about 5% or less, and still more preferably about 4% or less, and the lower limit is , about 0%, about 0.1%. Moreover, the range of the heat shrinkage rate is preferably about 0 to 10%, about 0 to 5%, about 0 to 4%, about 0.1 to 10%, about 0.1 to 5%, 0.1% to about 0.1%, about 0.1% to 5%, and 0.1% to about 0.1%. About 1 to 4% can be mentioned. The thermal shrinkage rate can be measured by a method conforming to JIS K 7133:1999. In addition, JIS K 7133 specifies that the test piece size is 120 mm × 120 mm, but if the thermal shrinkage rate can only be measured with a test piece smaller than the test piece size, the possible range Measure the thermal shrinkage rate in the same manner for a square test piece close to the test piece size.

The laminated film 10 of the present invention preferably has a seal strength of about 10 N/15 mm or more, more preferably about 20 N/15 mm or more when heat-sealed with the members (first member, second member) described later. is more preferred. Although there is no particular upper limit for the seal strength, it is usually about 100 N/15 mm or less. That is, the range of the seal strength is preferably about 10 to 100 N/15 mm, more preferably about 20 to 100 N/15 mm. In the laminated film 10 of the present invention in which the first member and the second member are heat-sealed, the seal strength when heat-sealed with these members has such a value, so that the obtained molded product has , it can be said that the first member and the second member are preferably joined via the laminated film 10 of the present invention. When the molten resin is heat-sealed to a solid member, it means the sealing strength when the laminated film 10 is heat-sealed to the resin member obtained by cooling and solidifying the molten resin. A specific method for measuring the seal strength is as follows. In addition, the seal strength when the laminated film 10 of the present invention and members (first member and second member) to be described later are heat-sealed is not limited to this range.

<Measurement of seal strength>
First, the laminate film is cut into a size of 50 mm in the length direction (y direction)×25 mm in the width direction (x direction). Next, the first heat-fusible resin layer or the second heat-fusible resin layer of the laminated film 10 and each member 50 are heat-sealed at a depth of 7 mm (y-direction) (heat-sealing conditions: temperature 190°C, surface pressure 1 MPa, pressure time 5 seconds) to obtain a test sample. In the schematic diagram of FIG. 6, a region S surrounded by a broken line indicates a heat-sealed region. A part other than the heat-sealed area is sandwiched with a release sheet so as to be heat-sealed at a depth of 7 mm. Next, the test sample is cut to a width of 15 mm as shown in FIG. 6(a) so that the seal strength (N/15 mm) at 15 mm in the width direction (x direction) can be measured. Next, using a tensile tester, as shown in FIG. 6B, the laminated film 10 is peeled off from the fixed member 50 in the longitudinal direction (y direction). At this time, the peeling speed is 300 mm/min, and the maximum load until peeling is the seal strength (N/15 mm). As for the members, resin members with a thickness of 4 mm and metal members or ceramic members with a thickness of 0.5 mm are used. Each seal strength is taken as an average value (n=3) measured by similarly producing three test samples.

Also, through the laminated film of the present invention, polypropylene (for example, Kobe Poly Sheet PP-N-BN manufactured by Hitachi Chemical Co., Ltd.) and aluminum (JIS H 4000: A1100 of 2014, arithmetic mean roughness Ra = 1.5 μm ) is preferably about 3 MPa or more, and more preferably about 4 MPa or more, as the shear strength of the molded article obtained by heat-sealing. Although the upper limit of the shear strength is not particularly limited, examples include about 50 MPa or less, about 30 MPa or less, about 15 MPa or less, and the like. above, about 8 MPa or more, and the like. Preferred ranges of the shear strength are about 3 to 50 MPa, about 4 to 50 MPa, about 8 to 50 MPa, about 3 to 30 MPa, about 4 to 30 MPa, about 8 to 30 MPa, about 3 to 15 MPa, about 4 to 15 MPa, 8 Up to about 15 MPa can be mentioned. The shear strength is a value measured by the following measuring method.

<Measurement of shear strength>
The shear strength is measured by a method conforming to ISO19095-2 and ISO19095-3. The sizes of aluminum and polypropylene are respectively 45 mm long×10 mm wide×1.5 mm thick. In addition, the laminated film has a length of 5 mm and a width of 10 mm. As shown in FIG. 11, the laminate film 10 was placed between the polypropylene 70 and the aluminum 80 at the ends in the length direction of the polypropylene 70 and the aluminum 80, and the temperature was 190° C., the surface pressure was 1.5 MPa, and 20 The polypropylene 70 and the aluminum 80 are heat-sealed via the laminated film 10 under conditions of seconds to obtain a molded body. Also, the laminated film 10 is arranged so that both sides are heat-sealed to the polypropylene 70 and the aluminum 80, respectively (that is, the heat-sealed area is 5 mm long by 10 mm wide on one side). Although not shown in FIG. 11, the polypropylene 70 and the aluminum 80 were each height-adjusted using a compensating member in order to perform the measurement on the parallel joints of the polypropylene 70 and the aluminum 80. Adjust the length and join. The compensating member for adjusting the height of the polypropylene 70 uses the same material and shape as the polypropylene 70 , and the compensating member for adjusting the height of the aluminum 80 uses the same material and shape as the aluminum 80 . Next, using a tensile tester, the molded body is pulled in the length direction (pulling speed is 10 mm / min), the maximum load (N) is measured, and the heat seal area (length 5 mm × width 10 mm) Divide by to calculate the shear strength (MPa).

(First heat-fusible resin layer 1)
In the present invention, the first heat-fusible resin layer 1 is a layer forming one surface of the laminated film of the present invention. That is, the first heat-fusible resin layer 1 constitutes the outermost layer on one side of the laminated film 10 of the present invention.

The heat-fusible resin contained in the first heat-fusible resin layer 1 is not particularly limited. includes modified polyolefins (ie, having a polyolefin backbone). A heat-fusible resin having a polyolefin skeleton is preferable as a heat-fusible resin contained in the first heat-fusible resin layer 1 because it has excellent solvent resistance to electrolytes and the like. The resin constituting the first heat-fusible resin layer 1 may or may not contain a polyolefin skeleton, but preferably contains a polyolefin skeleton from the above point of view. Whether the resin constituting the first heat-fusible resin layer 1 contains a polyolefin skeleton can be analyzed by, for example, infrared spectroscopy, gas chromatography mass spectrometry, or the like, and the analysis method is not particularly limited. For example, when maleic anhydride-modified polyolefin is measured by infrared spectroscopy, peaks derived from maleic anhydride are detected near wavenumbers of 1760 cm ⁻¹ and 1780 cm ⁻¹ .

Also, the modified polyolefin is preferably an acid-modified polyolefin. Acid-modified polyolefins specifically include polyolefins modified with unsaturated carboxylic acids or their anhydrides. Examples of unsaturated carboxylic acids or anhydrides thereof used for acid modification include maleic acid, acrylic acid, itaconic acid, crotonic acid, maleic anhydride, and itaconic anhydride.

The polyolefin to be modified is not particularly limited, but from the viewpoint of suitable thermal welding to inorganic members such as metals and ceramics, it is preferably low-density polyethylene, medium-density polyethylene, high-density polyethylene, or linear low-density polyethylene. polyethylene, such as density polyethylene; crystalline or amorphous polypropylene, such as homopolypropylene, block copolymers of polypropylene (e.g. block copolymers of propylene and ethylene), random copolymers of polypropylene (e.g. random copolymers of propylene and ethylene); ethylene -butene-propylene terpolymers. Among these, polypropylene is preferable as the modified polyolefin.

From the viewpoint of suitable heat welding to inorganic members such as metals and ceramics, among the heat-fusible resins contained in the first heat-fusible resin layer 1, maleic anhydride-modified polypropylene and maleic anhydride-modified polypropylene are particularly preferred. Modified polyolefins such as polyethylene are preferred.

The heat-fusible resin contained in the first heat-fusible resin layer 1 may be of one type, or may be of two or more types.

The proportion of the heat-fusible resin contained in the first heat-fusible resin layer 1 is not particularly limited. The content is preferably about 100% by mass or less, more preferably about 95% by mass or less, and even more preferably about 90% by mass or less. Further, the range of the ratio of the heat-welding resin is preferably about 70 to 100% by mass, about 70 to 95% by mass, about 70 to 90% by mass, about 80 to 100% by mass, and about 80 to 95% by mass. , about 80 to 90% by mass. The ratio of the heat-fusible resin contained in the first heat-fusible resin layer 1 has such a value, so that the laminated film 10 of the present invention can suitably exhibit heat-fusibility. Two or more members can be heat-sealed more favorably.

The first heat-fusible resin layer 1 preferably further contains an adhesive component. More specifically, the first heat-fusible resin layer 1 is preferably made of a heat-fusible resin composition containing an adhesive component. For example, when at least one of the first member and the second member is a solid member, the first heat-fusible resin layer 1 of the laminated film is suitable for use as a solid member because the first heat-fusible resin layer 1 contains an adhesive component. It is possible to detachably adhere (temporarily attach) the members to each other, suppress positional deviation during heat welding, and more preferably heat-weld two or more members. In the present invention, the term "temporary attachment" means to temporarily adhere, and is in a state in which even after temporarily adhering, it can be peeled off.

The adhesive component is not particularly limited as long as it can impart adhesiveness to the first heat-fusible resin layer 1. Examples include rosin, hydrogenated rosin, polymerized rosin, rosin ester, and rosin or derivatives thereof; Terpene resins such as pinene, β-pinene, and limonene; terpene phenol resins, coumarone-indene resins, styrene resins, xylene resins, phenol resins, petroleum resins, and hydrogenated petroleum resins. In addition, hydrogenated terpene resins, rosin resins, and petroleum resins are compatible with the elastomer phase of styrene-based block copolymers, and are highly effective in improving adhesion to non-polar materials such as polyolefins. Phenolic resins, styrene resins, etc. are compatible with the styrene phase and have the effect of increasing cohesion. Therefore, hydrogenated terpene resins, rosin resins, petroleum resins, and xylene resins, phenolic resins, styrene resins, etc. can be combined to form the adhesive component.

Amorphous polyolefin can also be used as the adhesive component. Examples of amorphous polyolefins include amorphous polypropylene, copolymers of amorphous propylene and other α-olefins, and specific examples include propylene/ethylene copolymers, propylene/butene-1 copolymers, and propylene.・Butene-1・ethylene・terpolymer, propylene・hexene-1・octene-1・terpolymer, propylene・hexene-1・4-methylpentene-1・terpolymer, propylene・hexene -1,4-methylpentene-1,terpolymer, polybutene-1, and the like. Among the target amorphous alpha-polyolefins, those having a large content of low-molecular-weight components and having a number average molecular weight of 20000 or less and a glass transition point of -20°C or less are preferred.

Amorphous polyolefin is preferable as the adhesive component. Commercially available amorphous polyolefins include, for example, REXtac2280 (manufactured by REXtac.LLC). In the first heat-fusible resin layer 1, for example, when REXtac2280 is used as the adhesive component and modified polyolefin is used as the heat-fusible resin, the content of REXtac2280 is about 10 parts per 100 parts by mass of the modified polyolefin. About 20 parts by mass or about 20 parts by mass is preferable.

An adhesive component may be used individually by 1 type, and may be used in combination of 2 or more types.

The proportion of the adhesive component contained in the first heat-fusible resin layer 1 is not particularly limited, but the lower limit is preferably about 1% by mass or more, more preferably about 5% by mass or more, and the upper limit is , preferably about 30% by mass or less, more preferably about 25% by mass or less. Moreover, the range of the proportion of the adhesive component is preferably about 1 to 30% by mass, about 1 to 25% by mass, about 5 to 30% by mass, and about 5 to 25% by mass. Since the ratio of the adhesive component contained in the first heat-fusible resin layer 1 has such a value, the laminated film of the present invention suitably exhibits excellent adhesiveness and heat-fusibility. It is possible to more preferably heat-weld two or more members. In particular, when at least one member is a solid member, the first heat-fusible resin layer of the laminated film can be suitably temporarily adhered to the solid member, and misalignment during heat-welding can be suppressed. , two or more members can be heat-welded more favorably.

The softening point of the first heat-fusible resin layer 1 is preferably about 90° C. or less, more preferably about 90° C. or less, from the viewpoint of more preferably heat-bonding two or more members with a good appearance after heat-welding. is about 80° C. or lower. Also, the lower limit of the softening point of the first heat-fusible resin layer 1 is, for example, approximately 40° C. or higher, preferably 50° C. or higher. Preferred ranges for the softening point of the first heat-fusible resin layer 1 include about 40 to 90°C, about 40 to 80°C, about 50 to 90°C, and about 50 to 80°C. In the present invention, the softening point of the first heat-fusible resin layer 1 is a value measured in the same manner as the softening point of the heat-resistant intermediate layer described below.

Although the thickness of the first heat-fusible resin layer 1 is not particularly limited, it reduces the heat shrinkage rate in a high-temperature environment during heat-sealing, improves the appearance after heat-sealing, and makes two or more members thicker. From the viewpoint of suitable thermal welding, the lower limit is preferably about 5 μm or more, more preferably about 10 μm or more, and still more preferably about 20 μm or more, and the upper limit is preferably about 200 μm or less, more preferably about 100 μm or less, more preferably about 50 μm or less. The thickness range of the first heat-fusible resin layer 1 is preferably about 5 to 200 μm, about 5 to 100 μm, about 5 to 50 μm, about 10 to 200 μm, about 10 to 100 μm, and about 10 to 50 μm. , about 20 to 200 μm, about 20 to 100 μm, and about 20 to 50 μm.

The material, softening point, thickness, etc. of the first heat-fusible resin layer 1 and the second heat-fusible resin layer 2 described later may be the same or different.

(Heat-resistant intermediate layer 3)
In the present invention, the heat-resistant intermediate layer 3 is located between the first heat-fusible resin layer 1 and the second heat-fusible resin layer 2, and ensures excellent heat resistance of the laminated film 10. .

The material constituting the heat-resistant intermediate layer 3 is not particularly limited as long as it has excellent heat resistance. Examples include polyester, polyimide, polyamide, epoxy resin, polyvinyl alcohol, polyphenylene sulfide, polyarylate, polycarbonate, acrylic resin, Examples include fluororesins, silicone resins, phenolic resins, polyetherimides, and mixtures and copolymers thereof. Also, the shape of the heat-resistant intermediate layer 3 is not particularly limited, and examples thereof include a film and a non-woven fabric.

Specific examples of polyesters include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, copolymer polyester mainly composed of repeating units of ethylene terephthalate, and butylene terephthalate mainly composed of repeating units. and copolymerized polyester. Further, as the copolymer polyester having ethylene terephthalate as the main repeating unit, specifically, a copolymer polyester polymerized with ethylene isophthalate having ethylene terephthalate as the main repeating unit (hereinafter referred to as polyethylene (terephthalate/isophthalate) ), polyethylene (terephthalate/isophthalate), polyethylene (terephthalate/adipate), polyethylene (terephthalate/sodium sulfoisophthalate), polyethylene (terephthalate/sodium isophthalate), polyethylene (terephthalate/phenyl-dicarboxylate) , polyethylene (terephthalate/decanedicarboxylate), and the like. Further, as the copolymer polyester having butylene terephthalate as the main repeating unit, specifically, a copolymer polyester polymerized with butylene isophthalate having butylene terephthalate as the main repeating unit (hereinafter referred to as polybutylene (terephthalate/isophthalate) ), polybutylene (terephthalate/adipate), polybutylene (terephthalate/sebacate), polybutylene (terephthalate/decanedicarboxylate), polybutylene naphthalate, and the like. These polyesters may be used singly or in combination of two or more.

From the viewpoint of reducing the thermal contraction rate in a high-temperature environment during heat welding, improving the appearance after heat welding, and more preferably heat-welding two or more members, among these, the heat-resistant intermediate layer 3 is preferred. Materials include polyethylene terephthalate, polyethylene naphthalate, polyimide, polyphenylene sulfide, aramid, vinylon (polyvinyl alcohol), or polyarylate. Moreover, the shape of the heat-resistant intermediate layer 3 includes a film, a fibrous nonwoven fabric, and the like. Among these, the heat-resistant intermediate layer 3 is composed of a polyethylene terephthalate film, a polyethylene naphthalate film, a polyimide film, a polyphenylene sulfide fiber nonwoven fabric, an aramid fiber nonwoven fabric, a vinylon (polyvinyl alcohol) fiber nonwoven fabric, or a polyarylate fiber nonwoven fabric. is preferred.

The heat-resistant intermediate layer 3 measures the amount of displacement of the probe using an atomic force microscope to which a cantilever (probe) with a heating mechanism is attached. When the probe is heated from 40°C to 220°C under the conditions of −4V and a heating rate of 5°C/min, the probe position must not fall below the initial value. is desirable. Since the heat-resistant intermediate layer 3 has such properties, the heat shrinkage rate in a high-temperature environment during heat welding can be further reduced, and the appearance after heat welding can be improved.

In addition, the heat-resistant intermediate layer 3 has a set value of -4 V for the deflection of the probe at the start of measurement, and the temperature rise is When the probe was heated from 40° C. to 220° C. at a rate of 5° C./min, the position of the probe placed on the surface of the heat-resistant intermediate layer in the cross section of the laminated film was the initial value (probe position when the temperature of is 40° C.). Since the heat-resistant intermediate layer 3 has such properties, the heat shrinkage rate in a high-temperature environment during heat welding can be further reduced, and the appearance after heat welding can be improved.

In the probe displacement measurement using an atomic force microscope to which a cantilever (probe) with a heating mechanism is attached, first, as shown in the conceptual diagram of FIG. (For example, in the case of the laminated film 10 in FIG. 13, the position of P) is set with the probe 90 (measurement start A in FIG. 12). The cross section at this time is the exposed portion of the cross section of the heat-resistant intermediate layer obtained by cutting in the thickness direction so as to pass through the central portion of the laminated film. Cutting can be performed using a commercially available rotating microtome or the like. As an atomic force microscope to which a cantilever (probe) with a heating mechanism is attached, for example, an afm plus system manufactured by ANASIS INSTRUMENTS is used, and a cantilever ThermaLever AN2-200 (spring constant 0.5 to 3 N/m) is used as the probe. can be used. The tip radius of the probe is 30 nm or less, the deflection setting value of the probe is -4 V, and the heating rate is 5° C./min. Next, when the probe is heated in this state, the heat from the probe 90 causes the surface of the heat-resistant intermediate layer 3 to expand as shown in FIG. (the position when the temperature of the probe 90 is 40° C.). When the temperature further rises, the heat-resistant intermediate layer softens, and the probe 90 may stick into the heat-resistant intermediate layer as shown in FIG. 12C, and the position of the probe 90 may drop. In measuring the amount of displacement of the probe 90, the laminated film to be measured is in a room temperature (25° C.) environment, and the probe 90 heated to 40° C. is placed on the surface of the heat-resistant intermediate layer in the cross section of the laminated film. to start measurement.

In the laminated film of the present invention, when the probe was heated from 40 ° C. to 220 ° C. under the conditions that the deflection of the probe at the start of measurement was -4 V and the temperature increase rate was 5 ° C./min, the laminated film The position of the probe installed on the surface of the heat-resistant intermediate layer in the cross section does not fall below the initial value (the position when the temperature of the probe is 40 ° C.), and when heated from 160 ° C. to 200 ° C., the lamination It is more preferable that the positions of the probes placed on the surface of the heat-resistant intermediate layer in the cross section of the film are not lowered. The process of heat-sealing a member using a laminated film is usually performed by heating to about 160°C to 200°C. Therefore, when the probe is heated from 160° C. to 200° C., the laminated film, in which the position of the probe placed on the surface of the heat-resistant intermediate layer in the cross section of the laminated film does not decrease, exhibits particularly high heat resistance. . From the viewpoint of further improving heat resistance, when the probe is heated from 40 ° C. to 250 ° C., the position of the probe installed on the surface of the heat-resistant intermediate layer in the cross section of the laminated film does not decrease from the initial value, and further, It is more preferable that the position of the probe placed on the surface of the heat-resistant intermediate layer in the cross section of the laminated film does not decrease when heated from 160°C to 200°C.

From the viewpoint of further increasing the heat resistance, the softening point of the heat-resistant intermediate layer 3 is preferably about 160° C. or higher, more preferably about 200° C. or higher. Although there is no particular upper limit for the softening point of the heat-resistant intermediate layer 3, for example, about 250° C. or less can be mentioned. Preferred ranges for the softening point of the heat-resistant intermediate layer 3 are about 160 to 250.degree. C. and about 200 to 250.degree. In the present invention, the softening point of the heat-resistant intermediate layer 3 is the temperature at which the deflection of the probe becomes maximum in the measurement of the displacement of the probe described above. In the measurement of the softening point of the heat-resistant intermediate layer 3, five samples of the heat-resistant intermediate layer to be measured were measured for the maximum deflection temperature of the probe. and the average value of the three temperatures excluding the minimum value is taken as the softening point.

Moreover, the softening point of the heat-resistant intermediate layer 3 is preferably higher than the softening point of the first heat-fusible resin layer 1 . Furthermore, the softening point of the heat-resistant intermediate layer 3 is preferably higher than the softening points of the first heat-fusible resin layer 1 and the softening points of the second heat-fusible resin layer 2 . The softening point of the heat-resistant intermediate layer 3 is preferably 30° C. or higher, more preferably 60° C. or higher, and even more preferably 90° C. or higher, than the softening point of the first heat-fusible resin layer 1 . The softening point of the heat-resistant intermediate layer 3 is preferably 8° C. or higher, more preferably 30° C. or higher, and even more preferably 90° C. or higher, than the softening point of the second heat-fusible resin layer 2 . .

Although the thickness of the heat-resistant intermediate layer 3 is not particularly limited, it reduces the heat shrinkage rate in a high temperature environment during heat welding, improves the appearance after heat welding, and more preferably heats two or more members. From the viewpoint of welding, the lower limit is preferably about 5 μm or more, more preferably about 10 μm or more, and the upper limit is preferably about 200 μm or less, more preferably about 100 μm or less. The thickness range of the heat-resistant intermediate layer 3 is preferably about 5 to 200 μm, about 5 to 100 μm, about 10 to 200 μm, and about 10 to 100 μm.

When the heat-resistant intermediate layer 3 is made of nonwoven fabric, the basis weight of the nonwoven fabric is not particularly limited, but layers adjacent to the heat-resistant intermediate layer 3 (for example, the first heat-fusible resin layer 1, the second From the viewpoint of sufficiently impregnating the nonwoven fabric with the heat-fusible resin layer 2, the thermoplastic resin layer 4, etc., and stabilizing the adhesive strength between the layers, the basis weight is preferably small, and the lower limit is preferably about 5 g/m. ² or more. Moreover, from the viewpoint of reducing the thermal shrinkage rate in a high-temperature environment during heat welding, the basis weight is preferably large, and the upper limit is 30 g/m ² or less. From the viewpoint of reducing the heat shrinkage rate in a high-temperature environment during heat welding, improving the appearance after heat welding, and more preferably heat-welding two or more members, the basis weight range is preferably 5. Up to about 30 g/m ² , more preferably about 7 to 25 g/m ² .

(Second heat-fusible resin layer 2)
In the present invention, the second heat-fusible resin layer 2 is a layer located on the opposite side of the heat-resistant intermediate layer 3 from the first heat-fusible resin layer 1 . The second heat-fusible resin layer 2 is composed of a heat-fusible resin composition. In the laminated film 10 of the present invention, the second heat-fusible resin layer 2 is replaced with the first heat-fusible resin layer from the viewpoint of suitably heat-bonding not only resin members but also inorganic members such as metals and ceramics. 1 constitutes the opposite surface.

The heat-fusible resin contained in the second heat-fusible resin layer 2 is not particularly limited, but it is preferable from the viewpoint of suitably heat-bonding not only resin members but also inorganic members such as metals and ceramics. includes modified polyolefins (ie, having a polyolefin backbone). In other words, the resin forming the second heat-fusible resin layer 2 may or may not contain a polyolefin skeleton, but preferably contains a polyolefin skeleton from the above point of view. A heat-fusible resin having a polyolefin skeleton is preferable as the heat-fusible resin contained in the second heat-fusible resin layer 2 because it has excellent solvent resistance to electrolytes and the like. Whether the resin constituting the second heat-fusible resin layer 2 contains a polyolefin skeleton can be analyzed by, for example, infrared spectroscopy, gas chromatography-mass spectrometry, or the like, and the analysis method is not particularly limited. For example, when maleic anhydride-modified polyolefin is measured by infrared spectroscopy, peaks derived from maleic anhydride are detected near wavenumbers of 1760 cm ⁻¹ and 1780 cm ⁻¹ .

Also, the modified polyolefin is preferably an acid-modified polyolefin. Acid-modified polyolefins specifically include polyolefins modified with unsaturated carboxylic acids or their anhydrides. Examples of unsaturated carboxylic acids or anhydrides thereof used for acid modification include maleic acid, acrylic acid, itaconic acid, crotonic acid, maleic anhydride, and itaconic anhydride.

The polyolefin to be modified is not particularly limited, but from the viewpoint of suitable thermal welding to inorganic members such as metals and ceramics, it is preferably low-density polyethylene, medium-density polyethylene, high-density polyethylene, or linear low-density polyethylene. polyethylene, such as density polyethylene; crystalline or amorphous polypropylene, such as homopolypropylene, block copolymers of polypropylene (e.g. block copolymers of propylene and ethylene), random copolymers of polypropylene (e.g. random copolymers of propylene and ethylene); ethylene -butene-propylene terpolymers. Among these, polypropylene is preferable as the modified polyolefin.

Among the heat-fusible resins contained in the second heat-fusible resin layer 2, maleic anhydride-modified polypropylene is particularly preferable from the viewpoint of suitable heat-fusibility to inorganic members such as metals and ceramics.

The heat-fusible resin contained in the second heat-fusible resin layer 2 may be of one type, or may be of two or more types.

The proportion of the heat-fusible resin contained in the second heat-fusible resin layer 2 is not particularly limited, but the lower limit is preferably about 70% by mass or more, more preferably about 80% by mass or more. The content is preferably about 100% by mass or less, more preferably about 95% by mass or less, and even more preferably about 90% by mass or less. Further, the range of the ratio of the heat-welding resin is preferably about 70 to 100% by mass, about 70 to 95% by mass, about 70 to 90% by mass, about 80 to 100% by mass, and about 80 to 95% by mass. , about 80 to 90% by mass. The ratio of the heat-fusible resin contained in the second heat-fusible resin layer 2 has such a value, so that the laminated film 10 of the present invention can suitably exhibit heat-fusibility. Two or more members can be heat-sealed more favorably.

The second heat-fusible resin layer 2 may contain an adhesive component, if necessary. When the second heat-fusible resin layer 2 contains an adhesive component, the second heat-fusible resin layer 2 can exhibit adhesiveness like the first heat-fusible resin layer 1 . In particular, when the second heat-fusible resin layer 2 constitutes the surface opposite to the first heat-fusible resin layer 1, the first heat-fusible resin layer 1 and the second heat-fusible resin Since the layer 2 contains an adhesive component, it becomes possible to temporarily bond both sides of the first heat-fusible resin layer 1 and the second heat-fusible resin layer 2 of the laminated film 10 to a solid member. Therefore, misalignment or the like when two or more solid members are heat-welded is suppressed, and two or more solid members can be suitably heat-welded.

When the second heat-fusible resin layer 2 contains an adhesive component, the type of the adhesive component is not particularly limited, and examples thereof are the same as those exemplified for the first heat-fusible resin layer 1 .

When the second heat-fusible resin layer 2 contains an adhesive component, the ratio is not particularly limited, but the lower limit is preferably about 1% by mass or more, more preferably about 5% by mass or more, The upper limit is preferably about 30% by mass or less, more preferably about 25% by mass or less. Moreover, the range of the proportion of the adhesive component is preferably about 1 to 30% by mass, about 1 to 25% by mass, about 5 to 30% by mass, and about 5 to 25% by mass. Since the ratio of the adhesive component contained in the second heat-fusible resin layer 2 has such a value, the laminated film of the present invention suitably exhibits excellent adhesiveness and heat-fusibility. It is possible to more preferably heat-weld two or more members. In particular, when at least one member is a solid member, the second heat-fusible resin layer of the laminated film can be suitably temporarily adhered to the solid member, and misalignment during heat-sealing can be suppressed. , two or more members can be heat-welded more favorably.

From the viewpoint of reducing the heat shrinkage rate in a high-temperature environment during heat welding, improving the appearance after heat welding, and more preferably heat-welding two or more members, the second heat-welding resin layer 2 is used. The softening point is preferably about 90°C or lower, more preferably about 80°C or lower. The lower limit of the softening point of the second heat-fusible resin layer 2 is, for example, approximately 40° C. or higher, preferably approximately 50° C. or higher. Preferred ranges for the softening point of the second heat-fusible resin layer 2 include about 40 to 90°C, about 40 to 80°C, about 50 to 90°C, and about 50 to 80°C. In the present invention, the softening point of the second heat-fusible resin layer 2 is a value measured in the same manner as the softening point of the heat-resistant intermediate layer.

Although the thickness of the second heat-welding resin layer 2 is not particularly limited, it reduces the heat shrinkage rate in a high-temperature environment during heat-welding, improves the appearance after heat-welding, and makes two or more members more uniform. From the viewpoint of suitable thermal welding, the lower limit is preferably about 5 μm or more, more preferably about 10 μm or more, and still more preferably about 20 μm or more, and the upper limit is preferably about 200 μm or less, more preferably about 100 μm or less, more preferably about 50 μm or less. The thickness range of the second heat-fusible resin layer 2 is preferably about 5 to 200 μm, about 5 to 100 μm, about 5 to 50 μm, about 10 to 200 μm, about 10 to 100 μm, and about 10 to 50 μm. , about 20 to 200 μm, about 20 to 100 μm, and about 20 to 50 μm.

(Thermoplastic resin layer 4)
In the present invention, the thermoplastic resin layer 4 is a layer laminated on the laminated film 10 as necessary. The thermoplastic resin layer 4 is preferably laminated between the first heat-fusible resin layer 1 and the heat-resistant intermediate layer 3 and between the heat-resistant intermediate layer 3 and the second heat-fusible resin layer 2. . The laminated film 10 may have one layer of the thermoplastic resin layer 4 laminated thereon, or may have two or more layers laminated thereon. The number of laminated thermoplastic resin layers 4 in the laminated film 10 is preferably about 0 to 2, more preferably about 0 to 1. When at least one of the first heat-fusible resin layer 1 and the second heat-fusible resin layer 2 contains an adhesive component, the layer containing the adhesive component is attached to the heat-resistant intermediate layer 3 via the thermoplastic resin layer 4. By laminating, the adhesive strength between layers can be stabilized. Therefore, for example, the first heat-fusible resin layer 1 and the second heat-fusible resin layer 2 constitute both sides of the laminated film 10, and the first heat-fusible resin layer 1 and the second heat-fusible resin layer 2 When an adhesive component is included, the thermoplastic resin layer 4 is provided between the first heat-fusible resin layer 1 and the heat-resistant intermediate layer 3 and between the heat-resistant intermediate layer 3, as in the laminate structure of FIG. and the second heat-fusible resin layer 2 are preferably laminated one by one. Further, for example, when the first heat-fusible resin layer 1 constitutes one side of the laminated film 10 and the first heat-fusible resin layer 1 contains an adhesive component, as in the laminated structure of FIG. One thermoplastic resin layer 4 is preferably laminated between the first heat-fusible resin layer 1 and the heat-resistant intermediate layer 3 .

The thermoplastic resin constituting the thermoplastic resin layer 4 is not particularly limited as long as it has thermoplasticity. Examples of thermoplastic resins include polyolefins, polyesters, polyamides, acrylic resins, fluororesins, and silicone resins. Among these, the thermoplastic resin layer 4 is preferably made of polyolefin, and more preferably made of modified polyolefin (that is, having a polyolefin skeleton). As the modified polyolefin, the same as those exemplified for the first heat-fusible resin layer 1 are preferably exemplified. That is, the resin forming the thermoplastic resin layer 4 may or may not contain a polyolefin skeleton, but preferably contains a polyolefin skeleton from the above point of view. A thermoplastic resin having a polyolefin skeleton is preferable as the thermoplastic resin contained in the thermoplastic resin layer 4 because it has excellent solvent resistance to the electrolytic solution and the like. Whether the resin constituting the thermoplastic resin layer 4 contains a polyolefin skeleton can be analyzed by, for example, infrared spectroscopy, gas chromatography mass spectrometry, or the like, and the analysis method is not particularly limited. For example, when maleic anhydride-modified polyolefin is measured by infrared spectroscopy, peaks derived from maleic anhydride are detected near wavenumbers of 1760 cm ⁻¹ and 1780 cm ⁻¹ .

In addition, the thermoplastic resin layer 4 may contain an adhesive component as needed. When the thermoplastic resin layer 4 contains an adhesive component, the thermoplastic resin layer 4 can exhibit adhesiveness. When the thermoplastic resin layer 4 contains an adhesive component, the type of the adhesive component is not particularly limited, and the same as those exemplified for the first heat-fusible resin layer 1 are exemplified. Moreover, the ratio of the adhesive component in the thermoplastic resin layer 4 is not particularly limited, and the same ratio as in the first heat-fusible resin layer 1 can be mentioned.

The softening point of the thermoplastic resin layer 4 is preferably about 90° C. or less, more preferably about 80° C. or less. The lower limit of the softening point of the thermoplastic resin layer 4 is, for example, approximately 40° C. or higher, preferably approximately 50° C. or higher. Preferred ranges for the softening point of the thermoplastic resin layer 4 include about 40 to 90°C, about 40 to 80°C, about 50 to 90°C, and about 50 to 80°C. In the present invention, the softening point of the thermoplastic resin layer 4 is a value measured in the same manner as the softening point of the heat-resistant intermediate layer.

The thickness of the thermoplastic resin layer 4 is not particularly limited. From the viewpoint of welding, the lower limit is preferably about 5 μm or more, more preferably about 10 μm or more, still more preferably about 20 μm or more, and the upper limit is preferably about 200 μm or less, more preferably about 100 μm or less. More preferably, it is about 50 μm or less. Further, the thickness range of the thermoplastic resin layer 4 is preferably about 5 to 200 μm, about 5 to 100 μm, about 5 to 50 μm, about 10 to 200 μm, about 10 to 100 μm, about 10 to 50 μm, 20 to 50 μm. About 200 μm, about 20 to 100 μm, and about 20 to 50 μm can be mentioned. In addition, when the thermoplastic resin layer 4 is provided in multiple layers, these thicknesses mean the thickness of one layer of the thermoplastic resin layer 4 .

(other layers)
In the laminated film 10 of the present invention, layers different from the first heat-fusible resin layer 1, the second heat-fusible resin layer 2, the heat-resistant intermediate layer 3, and the thermoplastic resin layer 4 are further laminated. may

(Additive)
The laminated film 10 of the present invention may contain various additives such as a lubricant, an antioxidant, an ultraviolet absorber, and a light stabilizer, if necessary. Note that the laminated film 10 may be discolored depending on the type and content of the additive.

(Method for manufacturing laminated film)
The laminated film 10 of the present invention comprises at least a first heat-fusible resin layer 1, a heat-resistant intermediate layer 3, a second heat-fusible resin layer 2, and an optional thermoplastic resin layer 4. It can be produced by lamination. A method for laminating these layers is not particularly limited, and for example, a thermal lamination method, a sandwich lamination method, an extrusion lamination method, or the like can be used.

Further, in the laminated film 10 of the present invention, when the heat-resistant intermediate layer 3 is composed of a resin film, an adhesion promoter is applied to both surfaces of the heat-resistant intermediate layer 3 (that is, an adhesion promoter layer is provided). Thus, the adhesion strength between adjacent layers (eg, the first heat-fusible resin layer 1, the second heat-fusible resin layer 2, the thermoplastic resin layer 4, etc.) can be improved and the laminated structure can be stabilized. Further, the surface of the heat-resistant intermediate layer 3 can be subjected to known easy-adhesion means such as corona discharge treatment, ozone treatment, plasma treatment, etc., if necessary.

As the adhesion promoter that forms the adhesion promoter layer, known adhesion promoters such as isocyanate, polyethyleneimine, polyester, polyurethane, and polybutadiene can be used. Moreover, the adhesion promoter layer can also be formed using a known adhesive such as a two-component curing adhesive or a one-component curing adhesive. As a result of experiments, it was found that the lamination strength was excellent with the isocyanate component selected from the triisocyanate monomer and the polymeric MDI, and the deterioration of the lamination strength was small. As the isocyanate-based adhesion promoter, one comprising an isocyanate component selected from triisocyanate monomer and polymeric MDI is excellent in lamination strength and less in deterioration of lamination strength after immersion in the electrolytic solution. In particular, triphenylmethane-4,4′,4″-triisocyanate, which is a triisocyanate monomer, and polymethylene polyphenyl polyisocyanate, which is a polymeric MDI (with an NCO content of about 30% and a viscosity of 200 to 700 mPa s), It is particularly preferable to use an adhesion promoter such as tris (p-isocyanate phenyl) thiophosphate, which is a triisocyanate monomer, or a two-liquid curing adhesive that uses a polycarbodiimide as a cross-linking agent and a polyethyleneimine-based base. Formation with an accelerator is also preferred.

The adhesion promoter layer can be provided on one side or both sides of the heat-resistant intermediate layer 3 . The adhesion promoter layer can be formed by coating and drying by a known coating method such as a bar coating method, a roll coating method, a gravure coating method, or the like. The coating amount of the adhesion promoter is 20 to 100 mg/m ² , preferably 40 to 60 mg/m 2 for the triisocyanate adhesion promoter, and 40 to 40 mg/m ² for the polymeric MDI adhesion promoter. Up to 150 mg/m ² , preferably 60 to 100 mg/m ² , and in the case of a two-liquid curing type adhesion promoter containing polyethyleneimine as a main component and polycarbodiimide as a cross-linking agent, 5 to 50 mg/m ² , It is preferably 10 to 30 mg/m ² . When using a known adhesive as an adhesion promoter, the upper limit of the coating amount is preferably about 10 g/m ² or less, and the lower limit is preferably about 1 g/m ² . The triisocyanate monomer is a monomer having three isocyanate groups in one molecule, and the polymeric MDI is a mixture of MDI and an MDI oligomer obtained by polymerizing MDI, represented by the following formula.

(Element)
Materials for the first member and the second member that are joined together by the laminated film 10 are not particularly limited, and resins, metals, ceramics, and the like can be mentioned, respectively. The materials forming the first member and the second member may be of the same type or of different types. Moreover, the first member and the second member may be in a molten state or in a solid state when they are joined by heat welding. A specific example of the member in a molten state is a molten resin. When the molten resin is cooled and solidified, it becomes a resin member. Moreover, examples of solid members include resin members and inorganic members (eg, metal members and ceramic members). In addition to the first member and the second member, other members may be joined using the laminated film of the present invention. That is, the number of members to be joined by the laminated film of the present invention is at least two. The materials constituting the other members may be of the same type as those of the first member and the second member, or may be of different types. or solid.

The mode of joining two or more members using the laminated film of the present invention is not particularly limited as long as two or more members are joined via the laminated film. In the case, the first member/laminated film/second member/laminated film/other member are laminated in order, or the first member and the other member are arranged side by side on one surface of the laminated film, and this lamination is performed. Examples include a mode in which the second member is arranged on the other surface of the film and the three members are joined via one laminated film. Further, the laminated film may exist on the entire surface between the first member and the second member to join these members, or may exist on a part between the first member and the second member to bond these members. You may join a member.

These members may contain various additives such as lubricants, antioxidants, ultraviolet absorbers, light stabilizers, colorants (pigments, dyes, etc.), if necessary.

Specific examples of materials constituting the members include resins such as polyolefin, polyester, polyamide, epoxy resin, acrylic resin, fluororesin, silicone resin, and ABS resin; aluminum, iron, stainless steel, copper, zinc, silver, gold, Metals such as magnesium, titanium, brass, nickel, or alloys containing at least one of these; Ceramics such as glass, alumina, and zirconia; Fiber-reinforced plastics such as glass fiber reinforced plastics, carbon fiber reinforced plastics, and aramid fiber reinforced plastics. etc. Among resins, polyolefins such as polyethylene and polypropylene, epoxy resins, and ABS resins are particularly preferable. Among metals, aluminum, iron, stainless steel, titanium, brass, nickel, etc. are preferable. Glass is preferable among ceramics.

Preferred combinations of the first member and the second member thermally welded by the laminated film 10 of the present invention include, for example, a combination of a resin member and a metal member, a combination of a resin member and a resin member, and a resin member and a ceramic member. , a combination of a metal member and a ceramic member, a combination of a metal member and a metal member, a combination of a ceramic member and a ceramic member, and the like. As will be described later, when the resin member is obtained by cooling and solidifying molten resin, molding and thermal welding can be performed in one step.

The shape and size of the member are not particularly limited, and the shape and size may be set according to the formed body to be manufactured by joining the members. Examples of the shape of the solid member include members having various shapes such as a film shape, a plate shape, a pin shape such as a thumbtack, a concave shape, a convex shape, and an uneven shape. Examples of the various shaped members include molded members. Further, the thickness of the solid member is, for example, about 5 μm to 20 mm. A compact having a desired shape can be suitably obtained by molding when joining members having such a shape and thickness. In the present invention, a molded article manufactured by joining members can be suitably used for applications such as automobile interior and exterior members. Therefore, the materials, shapes, sizes, etc. of the members can be selected to suit these uses.

2. Molded Body The molded body 20 of the present invention is characterized in that the first member 30 and the second member 40 are heat-sealed with the laminated film 10 of the present invention, as shown in the schematic diagram of FIG. . That is, the molded article 20 of the present invention is in a bonded state via the laminated film 10 of the present invention. The details of the laminated film 10, the first member 30, and the second member 40 of the present invention are as described above. The molded body 20 of the present invention only needs to have a shape in which the first member 30 and the second member 40 are joined via the laminated film 10, and the molded body 20 of the present invention may have any shape. can. For example, FIG. 5 shows an aspect in which the molded body 20 of the present invention is plate-shaped. Moreover, FIG. 10 shows a mode in which the molded body 20 of the present invention is deformed by a mold.

The molded article 20 of the present invention is formed by disposing the laminated film 10 between the first member 30 and the second member 40 and heat-sealing the first member 30 and the second member 40 via the laminated film 10. Manufactured by Specifically, in a state in which the laminated film 10 is arranged between the first member 30 and the second member 40, the surface of the laminated film 10 is thermally melted by applying heat and pressure. After that, by cooling the laminated film 10 , the heat-melted surface is solidified, and the first member 30 and the second member 40 are thermally welded (bonded) via the laminated film 10 .

The temperature at which the first member 30 and the second member 40 are heat-sealed via the laminated film 10 is not particularly limited as long as it is a temperature at which the surface of the laminated film 10 is thermally melted, but is preferably 140 to 280°C. about 160 to 250° C., more preferably about 160 to 250° C. Also, the pressure (surface pressure) for thermal welding is not particularly limited, but is preferably about 0.5 to 5 MPa, more preferably about 1 to 3 MPa. The heating/pressurizing time for thermal welding is usually about 5 to 30 seconds.

In the present invention, when at least one of the first member 30 and the second member 40 to be thermally welded is formed by cooling and solidifying molten resin, molding and thermal welding can be performed in one step. becomes. Specifically, while one surface of the laminated film 10 is in contact with one solid member, the molten resin is supplied to the other surface, and the molten resin is cooled while being molded with a mold or the like. molding and thermal welding of the solid member can be performed in one step.

The temperature of the molten resin when the molten resin is supplied to the surface of the laminated film 10 is not particularly limited as long as it is a temperature at which the molten resin 40a can be maintained in a molten state. From the viewpoint of suitably heat-sealing the molten resin 40a and the solid member (first member 30) via the film 10, the temperature is preferably about 150 to 300.degree. C., more preferably about 190 to 250.degree.

The resin constituting the molten resin is not particularly limited as long as it is a resin that melts by heat. Resins such as polyolefins, polyesters, polyamides, epoxy resins, acrylic resins, fluorine resins, silicone resins, and ABS resins can be used. Among resins, polyolefins such as polyethylene and polypropylene, epoxy resins, and ABS resins are particularly preferable.

Further, when one of the first member 30 and the second member 40 to be thermally welded is a solid member, for example, as shown in a series of schematic diagrams of FIGS. ), in a state in which the first heat-fusible resin layer 1 of the laminated film 10 is temporarily adhered (FIG. 7), the molten resin 40a is supplied to the surface of the laminated film 10 on the side of the second heat-fusible resin layer 2. (FIG. 8), the molten resin 40a and the solid member (first member 30) can be thermally welded via the laminated film 10 (FIGS. 9 and 10). Also in this case, as shown in FIG. 9, molding and thermal welding can be performed in one process by cooling the supplied molten resin while molding it with a mold 60 or the like. Further, as shown in FIGS. 9 and 10, when the solid member (first member 30) is flexible enough to be molded with a mold 60 or the like, molding of the solid member (first member 30) can be done at the same time.

3. Method for manufacturing a molded body in which a resin member and a solid member are joined In a case where the first member 30 is the solid member 31 and the second member 40 is the resin member 41, the resin member 41 and the solid member 31 are joined together. A method for manufacturing the compact 21 will be described in detail below.

The method for manufacturing the molded body 21 is a method for manufacturing a molded body in which a resin member and a solid member are joined, and includes steps of preparing a laminate in which a laminated film is arranged on a solid member; a step of supplying a molten resin to the surface of the laminated film; and a step of cooling and solidifying the molten resin to form a resin member and joining the resin member and the solid member via the laminated film. A first heat-fusible resin layer, a heat-resistant intermediate layer, and a second heat-fusible resin, which constitute at least one side surface of the laminated film (one side surface of the laminated film). and layers in this order.

The present invention is a method of joining a molten resin and a solid member to manufacture a molded body 21 (see the schematic diagram of FIG. 15) in which the resin member 41 and the solid member 31 are joined. The molded body 21 is in a bonded state via the laminated film 10 of the present invention. As will be described later, the resin member 41 is obtained by cooling and solidifying the molten resin 41 a in a molten state on the laminated film 10 to become a solid. The molded body 21 may have a shape in which the resin member 41 and the solid member 31 are joined via the laminated film 10, and the molded body 21 may have any shape. For example, FIG. 15 shows an aspect in which the molded body 21 is plate-shaped. Moreover, FIG. 19 shows a mode in which the molded body 21 is deformed by the mold.

The method for manufacturing the molded body 21 will be described more specifically with reference to FIGS. 16 to 19. FIG. In the manufacturing method of the molded body 21, first, as shown in FIG. In the laminate, it is sufficient that the laminated film 10 is placed on the solid member 31, and the laminated film 10 may be left standing without adhering to the solid member 31, or the laminated film 10 may be placed on the solid member 31. The laminated film 10 may be detachably adhered (temporarily attached) to the solid member 31 , or the laminated film 10 may be joined (for example, heat-sealed) to the solid member 31 . In this step, when the laminated film 10 is temporarily attached to the solid member 31, it is preferable to prepare a laminate by temporarily attaching the first heat-fusible resin layer 1 of the laminated film 10 onto the solid member 31. .

Next, as shown in FIG. 17, a molten resin 41a is supplied to the surface of the laminated body on the laminated film 10 side. The temperature of the molten resin 41a when the molten resin 41a is supplied to the surface of the laminated film 10 is not particularly limited as long as it is a temperature at which the molten resin 41a can be maintained in a molten state. From the viewpoint of suitably heat-bonding the molten resin 41a and the solid member 31 via the laminated film 10, the temperature is preferably about 150 to 300.degree. C., more preferably about 190 to 250.degree.

Next, the molten resin 41 a is cooled and solidified to form the resin member 41 . More specifically, as shown in FIG. 18, the molten resin 41a, the laminated film 10, and the solid member 31 are heated using a mold 60 or the like while the molten resin 41a is positioned on the surface of the laminated film.・Heat welding under pressure. At this time, the interface between the molten resin 41a and the laminated film 10 is thermally welded by solidifying the molten resin 41a during cooling after heating and pressurization. Further, the interface between the laminated film 10 and the solid member 31 is thermally welded by solidifying the heat-melted surface of the laminated film 10 on the side of the first heat-fusible resin layer 1 during cooling after heating and pressurization. be. In addition, when the laminated film 10 is previously joined to the solid member 31 by heat welding or the like, the surface of the laminated film 10 on the first heat-fusible resin layer 1 side does not need to be thermally melted in this step. good too.

Through these steps, a molded body 21 is obtained in which the solid member 31, the laminated film 10, and the resin member 41 are laminated in this order, as shown in FIG.

In the conventional method for joining solid members, it is necessary to join after forming the solid members 31 to be joined. and thermal welding with the solid member 31 can be performed at the same time.

Furthermore, as shown in the schematic diagrams of FIGS. 16 to 19, when the solid member 31 has flexibility that can be molded with a mold 60 or the like, molding of the molten resin 41a and the solid member 31, The heat welding of the molten resin 41a and the solid member 31 can also be performed at the same time. Thus, according to the method for manufacturing the molded body 21, joining and molding of two or more members can be performed at the same time.

The temperature at which the molten resin 41a and the solid member 31 are thermally welded via the laminated film 10 is not particularly limited, but the viewpoint is that the molten resin 41a and the solid member 31 are suitably thermally welded via the laminated film 10. , preferably about 140 to 280°C, more preferably about 160 to 250°C. Also, the pressure (surface pressure) for thermal welding is not particularly limited, but is preferably about 0.5 to 5 MPa, more preferably about 1 to 3 MPa. The heating/pressurizing time for thermal welding is usually about 5 to 30 seconds.

The resin composing the molten resin 41a is not particularly limited as long as it is a resin that melts by heat. Resins such as polyesters, polyamides, epoxy resins, acrylic resins, fluororesins, silicone resins and ABS resins can be used. Among resins, polyolefins such as polyethylene and polypropylene, epoxy resins, and ABS resins are particularly preferable.

The material constituting the solid member 31 is not particularly limited, and the resins exemplified as the resins constituting the molten resin 41a mentioned above; aluminum, iron, stainless steel, copper, zinc, silver, gold, magnesium, titanium, Metals such as brass, nickel, or alloys containing at least one of these; Ceramics such as glass, alumina, and zirconia; Fiber-reinforced plastics such as glass fiber reinforced plastics, carbon fiber reinforced plastics, and aramid fiber reinforced plastics. . Among resins, polyolefins such as polyethylene and polypropylene, epoxy resins, and ABS resins are particularly preferable. Among metals, aluminum, iron, stainless steel, titanium, brass, nickel, etc. are preferable. Glass is preferable among ceramics.

The molten resin 41a and the solid member 31 may each contain various additives such as lubricants, antioxidants, ultraviolet absorbers, light stabilizers, and colorants (pigments, dyes, etc.), if necessary.

Preferred combinations of the molten resin 41a and the solid member 31 thermally welded by the laminated film 10 include, for example, a combination of the molten resin 41a and a metal member, a combination of the molten resin 41a and a resin member, and a combination of the molten resin 41a and a ceramic member. and a combination of.

The shape and size of the resin member and the solid member formed by the molten resin are not particularly limited, and may be the shape and size according to the molded body 21 manufactured by joining the molten resin and the solid member. . Examples of the shapes of the resin member and the solid member include, for example, members having various shapes such as a film shape, a plate shape, a pin shape such as a thumbtack, a concave shape, a convex shape, and an uneven shape. Examples of the various shaped members include molded members. Also, the thickness of the member is, for example, about 5 μm to 20 mm. By molding when joining members having such a shape and thickness, a molded body 21 having a desired shape can be suitably obtained. The molded body 21 manufactured by bonding a resin member and a solid member in the present invention can be suitably used for applications such as interior members and exterior members of automobiles, for example. Therefore, the material, shape, size, etc. of the resin member and the solid member can be selected to suit these uses.

In the method of manufacturing the molded body 21, the laminated film 10 is used to thermally weld the molten resin 41a and the solid member 31 together. The laminate film 10 is the same as described above.

EXAMPLES The present invention will be described in detail below with reference to examples and comparative examples. However, the present invention is not limited to the examples.

In the examples and comparative examples, the softening point of the resin is a value measured by the following method.

(Measurement of softening point)
The softening point is measured by measuring the amount of displacement of the probe using an atomic force microscope to which a cantilever (probe) with a heating mechanism is attached. First, a probe is placed on the surface of the heat-resistant intermediate layer in the cross section of the laminated film. The cross section at this time is the exposed portion of the cross section of the heat-resistant intermediate layer obtained by cutting in the thickness direction so as to pass through the central portion of the laminated film. Cutting is performed using a commercially available rotating microtome or the like. An atomic force microscope to which a cantilever (probe) with a heating mechanism can be attached is used, and an afm plus system manufactured by ANASIS INSTRUMENTS is used. use. The tip radius of the probe is 30 nm or less, the deflection setting value of the probe is -4 V, and the heating rate is 5° C./min. Next, when the probe is heated in this state, the surface of the heat-resistant intermediate layer expands due to the heat from the probe, pushing up the probe and changing the position of the probe to the initial value (when the probe temperature is 40°C). position). When the temperature further rises, the heat-resistant intermediate layer softens, the probe sticks into the heat-resistant intermediate layer, and the position of the probe lowers. In measuring the displacement of the probe, the laminated film to be measured is in a room temperature (25° C.) environment, and the probe heated to 40° C. is placed on the surface of the heat-resistant intermediate layer to start the measurement. The softening point of the heat-resistant intermediate layer is the temperature at which the deflection of the probe becomes maximum in measuring the amount of displacement of the probe. In the measurement of the softening point of the heat-resistant intermediate layer, for five samples of the heat-resistant intermediate layer to be measured, the temperature at which the deflection of the probe was maximized was read, and the maximum and minimum values of the five temperatures were measured. Let the softening point be the average value of the three temperatures excluding .

In measuring the softening point of the first heat-fusible resin layer, the main surface 1a of the first heat-fusible resin layer of the laminated film (specifically, the heat-resistant intermediate layer side of the first heat-fusible resin layer A probe is placed on the surface of the opposite side (see FIG. 14), and the measurement is performed in the same manner as the softening point of the heat-resistant intermediate layer. In measuring the softening point of the second heat-fusible resin layer, a probe is placed on the surface of the second heat-fusible resin layer in the cross section of the protective film, and the softening point is measured in the same manner as the softening point of the heat-resistant intermediate layer. I do.

<Production of laminated film>
(Example 1)
T It was extruded and applied to a thickness of 30 μm using a die extruder to form a first heat-fusible resin layer (adhesive PEa, softening point 54° C.). Next, on the other side of the heat-resistant intermediate layer, a maleic anhydride-modified polypropylene resin is extruded and applied to a thickness of 30 μm using a T-die extruder to form a second heat-fusible resin layer (PPa, softening point 75° C.). First heat-fusible resin layer (adhesive PEa, thickness 30 μm)/heat-resistant intermediate layer (PEN, thickness 12 μm)/second heat-fusible resin layer (PPa, thickness 30 μm) was laminated in this order to obtain a laminated film.

(Example 2)
A first heat-fusible resin layer containing an adhesive component ( Adhesive PEa, 30 μm)/heat-resistant intermediate layer (PET, thickness 12 μm)/second heat-fusible resin layer (PPa, thickness 30 μm) were laminated in this order to obtain a laminated film.

(Example 3)
A first heat-fusible resin layer containing an adhesive component (adhesive A laminated film was obtained in which a layer of heat-resistant intermediate layer (PI, thickness 12 μm)/second heat-fusible resin layer (PPa, thickness 30 μm) was laminated in this order.

(Example 4)
An adhesive component was added in the same manner as in Example 1, except that a nonwoven fabric made of polyphenylene sulfide (PPS) resin (basis weight: 15 g/m ² , thickness: 25 µm, softening point: 160°C or higher) was used as the heat-resistant intermediate layer. First heat-fusible resin layer (adhesive PEa, thickness 30 μm) / heat-resistant intermediate layer (PPS non-woven fabric, basis weight 15 g/m ² , thickness 25 μm) / second heat-fusible resin layer (PPa, thickness 30 μm) were laminated in this order to obtain a laminated film.

(Example 5)
A first heat-resistant layer containing an adhesive component was formed in the same manner as in Example 1, except that a non-woven fabric made of aramid fibers (basis weight: 15 g/m ² , thickness: 50 µm, softening point: 160 ° C. or higher) was used as the heat-resistant intermediate layer. Adhesive resin layer (adhesive PEa, thickness 30 μm)/heat-resistant intermediate layer (aramid fiber non-woven fabric, basis weight 15 g/m ² , thickness 50 μm)/second heat-fusible resin layer (PPa, thickness 30 μm) A laminated film laminated in order was obtained.

(Example 6)
A first heat-resistant layer containing an adhesive component was prepared in the same manner as in Example 1, except that a non-woven fabric made of vinylon fibers (12 g/m ² in basis weight, 60 µm in thickness, 160°C or higher in softening point) was used as the heat-resistant intermediate layer. Adhesive resin layer (adhesive PEa, thickness 30 μm)/heat-resistant intermediate layer (vinylon fiber non-woven fabric, basis weight 12 g/m ² , thickness 60 μm)/second heat-fusible resin layer (PPa, thickness 30 μm) A laminated film laminated in order was obtained.

(Example 7)
A first nonwoven fabric containing an adhesive component was formed in the same manner as in Example 1 except that a nonwoven fabric made of polyarylate fiber (basis weight: 14 g/m ² , thickness: 60 µm, softening point: 160°C or higher) was used as the heat-resistant intermediate layer. Heat-fusible resin layer (adhesive PEa, thickness 30 μm)/heat-resistant intermediate layer (polyarylate fiber non-woven fabric, basis weight 14 g/m ² , thickness 60 μm)/second heat-fusible resin layer (PPa, thickness 30 μm) was laminated in this order to obtain a laminated film.

(Example 8)
A first heat-resistant intermediate layer containing an adhesive component was formed in the same manner as in Example 1, except that a nonwoven fabric made of polyarylate fiber (weight per unit area: 9 g/m ² , thickness: 45 µm, softening point: 160°C or higher) was used. Heat-fusible resin layer (adhesive PEa, thickness 30 μm)/heat-resistant intermediate layer (polyarylate fiber non-woven fabric, basis weight 9 g/m ² , thickness 45 μm)/second heat-fusible resin layer (PPa, thickness 30 μm) was laminated in this order to obtain a laminated film.

(Example 9)
On one side of a polyethylene naphthalate (PEN) film (thickness: 12 μm, softening point: 160° C. or higher) as a heat-resistant intermediate layer, a maleic anhydride-modified polypropylene resin is extruded and applied to a thickness of 30 μm using a T-die extruder. , a thermoplastic resin layer (PPa, softening point 75° C.) was formed. Next, on the surface of the thermoplastic resin layer, a heat-fusible resin composition containing an adhesive component and a maleic anhydride-modified polyethylene resin is extruded and applied to a thickness of 30 μm using a T-die extruder to form a first heat-fusible resin layer. (tacky PEa, softening point 54° C.) was formed. Next, on the other side of the heat-resistant intermediate layer, a maleic anhydride-modified polypropylene resin is extruded and applied to a thickness of 30 μm using a T-die extruder to form a second heat-fusible resin layer (PPa, softening point 75° C.). First heat-fusible resin layer (adhesive PEa, thickness 30 μm)/thermoplastic resin layer (PPa, thickness 30 μm)/heat-resistant intermediate layer (PEN, thickness 12 μm)/second A laminated film was obtained in which heat-fusible resin layers (PPa, thickness 30 μm) were laminated in this order.

(Example 10)
On one side of a polyethylene naphthalate (PEN) film (thickness: 12 μm, softening point: 160° C. or higher) as a heat-resistant intermediate layer, a maleic anhydride-modified polypropylene resin is extruded and applied to a thickness of 30 μm using a T-die extruder. , a first heat-fusible resin layer (PPa, softening point 75° C.) was formed. Next, on the other side of the heat-resistant intermediate layer, a maleic anhydride-modified polypropylene resin is extruded and applied to a thickness of 30 μm using a T-die extruder to form a second heat-fusible resin layer (PPa, softening point 75° C.). A first heat-fusible resin layer (PPa, thickness 30 μm)/heat-resistant intermediate layer (PEN, thickness 12 μm)/second heat-fusible resin layer (PPa, thickness 30 μm) were laminated in this order. A laminated film was obtained.

(Comparative example 1)
An unstretched polypropylene film (CPP, thickness 50 μm, softening point 84° C.) was used as a heat-fusible film.

(Comparative example 2)
A maleic anhydride-modified polypropylene resin film (PPa, thickness 50 μm, softening point 75° C.) was used as a heat-fusible film.

<Probe displacement measurement>
In the probe displacement measurement using an atomic force microscope to which a cantilever (probe) with a heating mechanism is attached, all the heat-resistant intermediate layers used in Examples 1 to 10 are set for probe deflection at the start of measurement. When the probe was heated from 40°C to 220°C under the conditions of -4 V and a heating rate of 5°C/min, the temperature of the probe mounted on the surface of the heat-resistant intermediate layer in the cross section of the laminated film increased to at least 160°C. The position did not fall below the initial value (the position when the temperature of the probe was 40°C). The displacement of the probe was measured using an afm plus system manufactured by ANASIS INSTRUMENTS as an atomic force microscope to which a cantilever (probe) with a heating mechanism was attached. 5-3 N/m) was used. Further, the tip radius of the probe was 30 nm or less, the deflection setting value of the probe was -4 V, and the heating rate was 5°C/min. The details of probe displacement measurement are as described above.

<Measurement of heat shrinkage>
The heat shrinkage rate of each laminate film (each heat-welding film) obtained above was measured under the conditions of a test temperature of 200° C. and a heating time of 10 seconds in a method conforming to JIS K 7133:1999. Table 1 shows the results.

<Measurement of seal strength>
The seal strength (N/15 mm) between each surface of each laminated film (heat-fusible film) obtained above and each member listed in Table 1 was measured. Specifically, first, each laminated film was cut into a size of 50 mm in the length direction (y direction)×25 mm in the width direction (x direction). Next, as shown in FIG. 6, the first heat-fusible resin layer (adhesive PEa) or the second heat-fusible resin layer (PPa) of each laminated film 10 of Examples 1 to 9, and each member 50 were heat-sealed at a depth of 7 mm (y-direction) (heat-sealing conditions: temperature 190° C., surface pressure 1 MPa, pressure time 5 seconds) to obtain a test sample. In the schematic diagram of FIG. 6, a region S surrounded by a broken line indicates a heat-sealed region. A release sheet was sandwiched in the area other than the area to be heat-sealed so that the heat-sealing was performed at a depth of 7 mm. Next, the test sample was cut to a width of 15 mm as shown in FIG. 6(a) so that the seal strength (N/15 mm) at 15 mm in the width direction (x direction) could be measured. Next, using a tensile tester, as shown in FIG. 6B, the laminated film 10 was peeled off from the fixed member 50 in the longitudinal direction (y direction). At this time, the peeling speed was 300 mm/min, and the maximum load until peeling was taken as the seal strength (N/15 mm). Table 1 shows the results. As for the members, a resin member having a thickness of 4 mm and a metal member or a ceramic member having a thickness of 0.5 mm were used. Each seal strength is an average value (n=3) measured by making three test samples in the same manner.

Each heat-fusible film of Comparative Examples 1 and 2 is a single-layer film (CPP or PPa), and the laminated film of Example 10 has a first heat-fusible film composed of maleic anhydride-modified polypropylene resin on both sides. Since it is a flexible laminate (PPa) and a second heat-welding laminate (PPa), in Comparative Examples 1-2 and Example 10, the seal strength (N / 15 mm) was obtained in the same manner as in Examples 1-9 on one side only. was measured. Table 1 shows the results.

<Appearance after heat welding>
When measuring the seal strength, the appearance of each laminated film after thermal welding by heat sealing was visually observed and evaluated according to the following criteria. At this time, the joint surface between the first heat-fusible resin layer of the laminated film and the member was visually observed to confirm the positional deviation. Table 1 shows the results.
A: Good appearance without wrinkles and misalignment B: No wrinkles but misalignment C: Poor appearance with wrinkles and misalignment

<Measurement of shear strength>
Using each laminated film of Example 9 and Example 10, polypropylene (Kobe poly sheet PP-N-BN manufactured by Hitachi Chemical Co., Ltd.) and aluminum (JIS H 4000: A1100 of 2014, arithmetic mean The shear strength (MPa) of the molded body obtained by heat-welding the roughness (Ra=1.5 μm) was measured. The shear strength was measured by a method conforming to ISO19095-2 and ISO19095-3. The size of aluminum and polypropylene was 45 mm long×10 mm wide×1.5 mm thick, respectively. Each laminated film of Examples 9 and 10 was 5 mm long and 10 mm wide. As shown in FIG. 11, the laminate film 10 was placed between the polypropylene 70 and the aluminum 80 at the ends in the length direction of the polypropylene 70 and the aluminum 80, and the temperature was 190° C., the surface pressure was 1.5 MPa, and 20 The polypropylene 70 and the aluminum 80 were heat-sealed with the laminated film 10 interposed therebetween under conditions of seconds to obtain a molding. Also, the laminated film 10 was arranged so that both sides were entirely heat-sealed (that is, the heat-sealed area was 5 mm long by 10 mm wide on one side). Although not shown in FIG. 11, the polypropylene 70 and the aluminum 80 were each height-adjusted using a compensating member in order to perform the measurement on the parallel joints of the polypropylene 70 and the aluminum 80. It was joined by adjusting the thickness. The compensating member for adjusting the height of the polypropylene 70 has the same material and shape as the polypropylene 70 , and the compensating member for adjusting the height of the aluminum 80 has the same material and shape as the aluminum 80 . Next, using a tensile tester, the molded body is pulled in the length direction (pulling speed is 10 mm / min), and the maximum load (N) until delamination or breakage of the molded body occurs is measured. The shear strength (MPa) was calculated by dividing by the heat seal area (length 5 mm x width 10 mm). As a result, when the laminated film of Example 9 was used, the shear strength was 4.4 MPa, and when the laminated film of Example 10 was used, the shear strength was 13.9 MPa.

* 1 In Table 1, in Comparative Examples 1 and 2, the first heat-fusible resin layer or the second heat-fusible resin layer was not heat-welded with the member, but an unstretched polypropylene film (CPP) or maleic anhydride, respectively. The result of thermal welding between an acid-modified polypropylene resin film (PPa) and a member is shown.

In Table 1, "adhesive PEa" means the first heat-fusible resin layer composed of a maleic anhydride-modified polyethylene resin composition containing an adhesive component, and "PPa" means a maleic anhydride-modified polypropylene resin. It means a composed layer (first heat-fusible resin layer, second heat-fusible resin layer, thermoplastic resin layer, or maleic anhydride-modified polypropylene resin film). In addition, "PEN" is polyethylene naphthalate, "PET" is polyethylene terephthalate, "PI" is polyimide, "PPS nonwoven fabric" is nonwoven fabric made of polyphenylene sulfide (PPS) resin, "CPP" is unstretched polypropylene, and "PP". is polypropylene, "Epoxy" is epoxy resin, "PE" is polyethylene, "AL" is aluminum, "ABS" is acrylonitrile-butadiene-styrene copolymer, "SUS" is stainless steel, and "CFRP" is carbon fiber reinforced plastic. means

The laminated films of Examples 1 to 10 each include at least a first heat-fusible resin layer, a heat-resistant intermediate layer, and a second heat-fusible resin layer in this order, and two or more members are preferably used. It was possible to heat-weld to More specifically, the laminated films of Examples 1 to 10 were able to suitably heat-seal various resin members and solid members.

1 First heat-fusible resin layer 2 Second heat-fusible resin layer 3 Heat-resistant intermediate layer 4 Thermoplastic resin layer 10 Laminated film 20 Molded body 21 Molded body 30 First member 31 Solid member 40 Second member 41 Resin member 40a Molten resin 41a Molten resin 50 Member 60 Mold 70 Polypropylene 80 Aluminum 90 Probe S Heat-sealed region P Position of surface of heat-resistant intermediate layer in cross section of laminated film

Claims (11)

A laminated film for joining the first member and the second member,
The laminated film comprises at least a first heat-fusible resin layer, a heat-resistant intermediate layer, and a second heat-fusible resin layer in this order,
The heat-resistant intermediate layer is made of polyester, polyimide, polyamide, epoxy resin, polyvinyl alcohol, polyphenylene sulfide, polyarylate, polycarbonate, acrylic resin, fluororesin, silicone resin, phenolic resin, polyetherimide, mixtures thereof, and mixtures thereof. It is composed of at least one selected from the group consisting of copolymers,
The first heat-fusible resin layer and the second heat-fusible resin layer each contain modified polypropylene,
Each of the first heat-fusible resin layer and the second heat-fusible resin layer has a thickness of 5 μm or more,
A laminated film, wherein the shape of the heat-resistant intermediate layer is a non-woven fabric. A laminated film for joining the first member and the second member,
The laminated film comprises at least a first heat-fusible resin layer, a heat-resistant intermediate layer, and a second heat-fusible resin layer in this order,
The heat-resistant intermediate layer is made of polyester, polyimide, polyamide, epoxy resin, polyvinyl alcohol, polyphenylene sulfide, polyarylate, polycarbonate, acrylic resin, fluororesin, silicone resin, phenolic resin, polyetherimide, mixtures thereof, and mixtures thereof. It is composed of at least one selected from the group consisting of copolymers,
The first heat-fusible resin layer is made of modified polyolefin,
The first heat-fusible resin layer contains an adhesive component,
The second heat-fusible resin layer contains modified polypropylene,
The thickness of the second heat-fusible resin layer is 5 μm or more,
A laminated film, wherein the shape of the heat-resistant intermediate layer is a non-woven fabric. 3. The laminated film according to claim 1, wherein the thickness of said first heat-fusible resin layer is 200 [mu]m or less. The laminated film according to any one of claims 1 to 3 , wherein the heat-resistant intermediate layer has a thickness of 200 µm or less. The laminated film according to any one of claims 1 to 4 , wherein the thickness of the second heat-fusible resin layer is 200 µm or less. 6. The laminated film according to any one of claims 1 to 5 , having a heat shrinkage rate of 10% or less measured under conditions of a test temperature of 200°C and a heating time of 10 seconds. The laminated film according to any one of claims 1 to 6 , wherein the resin constituting the first heat-fusible resin layer has a polyolefin skeleton. The laminated film according to any one of claims 1 to 7 , wherein the first heat-fusible resin layer contains modified polyolefin. The laminated film according to any one of claims 1 to 8 , wherein when the first heat-fusible resin layer is analyzed by infrared spectroscopy, a peak derived from maleic anhydride is detected. A molded body obtained by joining polypropylene having a length of 45 mm, a width of 10 mm, and a thickness of 1.5 mm to aluminum having a length of 45 mm, a width of 10 mm, and a thickness of 1.5 mm through the laminated film, and having a shear strength of 3 MPa or more. The laminated film according to any one of claims 1 to 9 . A molded article, wherein the first member and the second member are joined via the laminated film according to any one of claims 1 to 10 .

Images