Adhesive film, flexible metal-clad laminate, and processes for producing these
View Patent ↗The present invention relates to an adhesive film with which a flexible metal-clad laminate is obtained with suppressed dimensional changes occurred when produced by a laminating method; and a flexible metal-clad laminate comprising the adhesive film and a metal foil bonded thereto. The adhesive film comprises a polyimide film and, formed on at least one side thereof, an adhesive layer comprising a thermoplastic polyimide and has coefficients of linear expansion satisfying the relationship 1.0>(coefficient of linear expansion in the MD direction)/(coefficient of linear expansion in the TD direction)>0.1. This adhesive film may be one produced continuously and further satisfying the relationship 1.70>(elastic modulus in the MD direction)/(elastic modulus in the TD direction)>1.05 when the adhesive film has an MD modulus of 5 GPa or higher throughout the whole width thereof. That adhesive film may be one produced continuously and further satisfying the relationship 2.00>(elastic modulus in the MD direction)/(elastic modulus in the TD direction)>1.10 when the adhesive film has an MD modulus less than 5 GPa throughout the whole thereof.
1. An adhesive film comprising:
a polyimide film; and
an adhesive layer containing a thermoplastic polyimide formed on at least one surface of the polyimide film,
wherein a coefficient of linear expansion of the adhesive film satisfies the relationship:
0.8>(coefficient of linear expansion in the MD direction)/(coefficient of linear expansion in the TD direction)>0.1
wherein the coefficient of linear expansion is an average value in the temperature range of 100° C. to 200° C.
2. An adhesive film comprising:
a polyimide film; and
an adhesive layer containing a thermoplastic polyimide formed on at least one surface of the polyimide film,
wherein the adhesive film is produced by a continuous process and has a coefficient of linear expansion across the entire width of the adhesive film satisfying the relationship:
0.8>(coefficient of linear expansion in the MD direction)/(coefficient of linear expansion in the TD direction)>0.1
wherein the coefficient of linear expansion is an average value in the temperature range of 100° C. to 200° C.
3. The adhesive film according to claim 2 , wherein the adhesive film is a long film having a width of 250 mm or more.
4. The adhesive film according to claim 2 , wherein a metal foil can be bonded in a continuous process onto the adhesive film under heating and pressure using at least one pair of metal rollers.
5. A flexible metal-clad laminate comprising:
the adhesive film according to claim 1 ; and
a metal foil bonded onto the adhesive film.
6. A method for making a flexible metal-clad laminate, comprising:
bonding a metal foil onto the adhesive film according to claim 1 by a continuous process under heating and pressure.
7. An adhesive film comprising:
a polyimide film; and
an adhesive layer containing a thermoplastic polyimide formed on at least one surface of the polyimide film,
wherein the adhesive film has an elastic modulus in the MD direction of 5 GPa or more and satisfies the relationship:
1.70>(elastic modulus in the MD direction)/(elastic modulus in the TD direction)>1.05.
8. An adhesive film comprising:
a polyimide film; and
an adhesive layer containing a thermoplastic polyimide formed on at least one surface of the polyimide film,
wherein the adhesive film is produced by a continuous process and satisfies the relationship:
1.70>(elastic modulus in the MD direction)/(elastic modulus in the TD direction)>1.05
when the elastic modulus of the adhesive film in the MD direction across the entire width is 5 GPa or more.
9. The adhesive film according to claim 8 , wherein the adhesive film is a long film having a width of 250 mm or more.
10. The adhesive film according to claim 8 , wherein the adhesive film is used in a continuous process of bonding a metal foil onto the adhesive film under heating and pressure using at least one pair of metal rollers.
11. A flexible metal-clad laminate comprising:
the adhesive film according to claim 7 ; and
a metal foil bonded onto the adhesive film.
12. A method for making a flexible metal-clad laminate, comprising:
bonding a metal foil onto the adhesive film according to claim 7 by a continuous process under heating and pressure.
13. An adhesive film comprising:
a polyimide film; and
an adhesive layer containing a thermoplastic polyimide formed on at least one surface of the polyimide film,
wherein the adhesive film has an elastic modulus in the MD direction of less than 5 GPa and satisfies the relationship:
2.00>(elastic modulus in the MD direction)/(elastic modulus in the TD direction)>1.10.
14. The adhesive film according to claim 13 , wherein the adhesive film is a long film having a width of 250 mm or more.
15. The adhesive film according to claim 13 , wherein the adhesive film is used in a continuous process of bonding a metal foil onto the adhesive film under heating and pressure using at least one pair of metal rollers.
16. An adhesive film comprising:
a polyimide film; and
an adhesive layer containing a thermoplastic polyimide formed on at least one surface of the polyimide film,
wherein the adhesive film is produced by a continuous process and satisfies the relationship:
2.00>(elastic modulus in the MD direction)/(elastic modulus in the TD direction)>1.10
when the elastic modulus of the adhesive film in the MD direction across the entire width is less than 5 GPa.
17. The adhesive film according to claim 16 , wherein the adhesive film is a long film having a width of 250 mm or more.
18. The adhesive film according to claim 16 , wherein the adhesive film is used in a continuous process of bonding a metal foil onto the adhesive film under heating and pressure using at least one pair of metal rollers.
19. A flexible metal-clad laminate comprising:
the adhesive film according to claim 13 ; and
a metal foil bonded onto the adhesive film.
20. A method for making a flexible metal-clad laminate, comprising:
bonding a metal foil onto the adhesive film according to claim 13 by a continuous process under heating.