Process for the production of packaging material for electronic component cases

1. A method of producing a packaging material, comprising:

a temporary bonding which temporarily bonds a first sheet comprising a thermoplastic resin non-oriented film layer and a thermoplastic adhesive resin layer laminated on one surface of the thermoplastic resin non-oriented film layer and a second sheet comprising a heat resistant resin oriented film layer and an aluminum foil layer laminated on one surface of the heat resistant resin oriented film layer by passing the first sheet and the second sheet between a first pair of rolls in a state in which the thermoplastic adhesive resin layer and the aluminum foil layer are brought into contact with each other to press the thermoplastic adhesive resin layer and the aluminum foil layer while heating in a state in which the thermoplastic adhesive resin does not melt to obtain a pre-laminated sheet; and

a complete bonding which integrally bonds the first sheet and the second sheet by heating the pre-laminated sheet to melt the thermoplastic adhesive resin,

wherein at the complete bonding, the pre-laminated sheet is heated by bringing the pre-laminated sheet into contact with a heating roll which is one of the first pair of rolls, and the other of the first pair of rolls is out of contact with the heating roll and the pre-laminated sheet when the pre-laminated sheet is brought into contact with the heating roll.

2. The method as recited in claim 1 , wherein at the temporary bonding, the first sheet and the second sheet are passed between the first pair of rolls comprising a rubber roll and a heating roll.

3. The method as recited in claim 1 , wherein the temporary bonding satisfies:

( M− 60)≦ T ≦( M− 5),

where M is a melting point of the thermoplastic adhesive resin, and T is a temperature of the thermoplastic adhesive resin at a time of pressing.

4. The method as recited in claim 1 , wherein at the temporary bonding, a pre-bonded sheet obtained by pressing the first sheet and the second sheet with the first pair of rolls is cooled by bringing into contact with a cooling roll to obtain the pre-laminated sheet, and at the complete bonding, an integrally bonded sheet obtained by integrally bonding the first sheet and the second sheet is cooled by bringing into contact with a cooling roll.

5. The method as recited in claim 4 , wherein the first pair of rolls comprises a heating roll, and the temporary bonding and the complete bonding satisfy:

( X− 80)≦ Y ≦( X− 10),

where X is a temperature of the heating roll, and Y is a temperature of the cooling roll.

6. The method as recited in claim 4 , wherein the first pair of rolls comprises a heating roll, and the temporary bonding and the complete bonding satisfy:

1.01 W≦Z≦ 1.30 W,

where W is a circumferential direction traveling speed of an external peripheral surface of the heating roll, and Z is a circumferential direction traveling speed of an external peripheral surface of the cooling roll.

7. The method as recited in claim 1 , wherein the thermoplastic resin non-oriented film is at least one non-oriented film comprising a thermoplastic resin selected from the group consisting of polyethylene, polypropylene, olefin series copolymer, acid modification thereof and ionomer, and the heat resistant resin oriented film is an oriented film comprising polyamide or polyester.

8. The method as recited in claim 1 , wherein at the complete bonding, the pre-laminated sheet is put around a pre-heating roll to perform pre-heating before being brought into contact with the heating roll.

9. The method as recited in claim 8 , wherein at the complete bonding, the pre-heating roll is set at a temperature of 40 to 150° C.

10. The method as recited in claim 1 , wherein at the complete bonding, the heating roll is set at a temperature of 180 to 220° C.

11. The method as recited in claim 1 , wherein the other of the first pair of rolls is a rubber roll.

12. The method as recited in claim 1 , wherein the other of the first pair of rolls is moved away from the heating roll before bringing the pre-laminated sheet into contact with the heating roll.

13. The method as recited in claim 1 , wherein a pair of pressing rolls comprising a heating roll and a rubber roll is employed as the first pair of rolls, and after the first sheet and the second sheet are passed between the pair of pressing rolls at the temporary bonding, the rubber roll is moved away from the heating roll such that the rubber roll is out of contact with the heating roll and the pre-laminated sheet when the pre-laminated sheet is brought into contact with the heating roll.

14. The method as recited in claim 4 , wherein the first pair of rolls comprises a heating roll, and the temporary bonding and the complete bonding satisfy:

( X− 50)≦ Y ≦( X− 30),

where X is a temperature of the heating roll, and Y is a temperature of the cooling roll.

15. The method as recited in claim 4 , wherein the first pair of rolls comprises a heating roll, and the temporary bonding and the complete bonding satisfy:

1.1 W≦Z≦ 1.15 W,

where W is a circumferential direction traveling speed of an external peripheral surface of the heating roll, and Z is a circumferential direction traveling speed of an external peripheral surface of the cooling roll.

16. The method as recited in claim 4 , wherein at the temporary bonding, the cooling roll is set at a temperature of 50 to 130° C.

17. The method as recited in claim 4 , wherein at the compete bonding, the cooling roll is set at a temperature of 50 to 150° C.