Thermosetting resin composition, method for forming protective film for flexible wiring board, and flexible wiring board

Patent metadata

Field	Value
Publication number	US-9781836-B2
Application number	US-201013499928-A
Country	US
Kind code	B2
Filing date	Oct 5, 2010
Priority date	Oct 7, 2009
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A thermosetting resin composition which contains a polyurethane resin and a curing agent, the polyurethane resin including a constitutional unit derived from an alicyclic diol and having an acid value of 10 to 35 mgKOH/g.

First claim

The invention claimed is:

1. A thermosetting resin composition comprising:
a polyurethane resin comprising a constitutional unit derived from an alicyclic diol in an amount of 0.1 to 30 mass % of the total mass polyurethane resin, the polyurethane resin having an acid value of 10 to 31 mgKOH/g; and
a curing agent comprising an epoxy resin,
wherein the polyurethane resin has been synthesized by:
reacting a diol including an alicyclic diol or a polycarbonatediol having a constitutional unit derived from an alicyclic diol with a polyisocyanate having an isocyanate group to obtain a polyisocyanate having a urethane linkage, and reacting the polyisocyanatel having the urethane linkage with an acid anhydride; or
reacting a diol including an alicyclic diol or a polycarbonatediol having a constitutional unit derived from an alicyclic diol and a dihydroxy compound having a carboxyl group with a polyisocyanate having an isocyanate group.

2. The thermosetting resin composition according to claim 1 , wherein the polyurethane resin has an amide linkage and/or an imide linkage.

3. The thermosetting resin composition according to claim 1 , wherein the polyurethane resin further comprises a constitutional unit derived from a polycarbonate diol represented by the following formula (2):

in the formula (2), R represents an alkylene group having 1 to 18 carbon atoms, and m represents an integer of 1 to 30.

4. A method for forming a protective film for a flexible wiring board, the method comprising the steps of:
printing the thermosetting resin composition according to claim 1 so as to cover at least a portion of a wiring pattern of the flexible wiring board, the wiring pattern being subjected to a Sn plating processing in advance; and
curing the printed thermosetting resin composition to form a protective film.

5. A flexible wiring board comprising a protective film formed by the method according to claim 4 .

6. A method for forming a protective film for a flexible wiring board, the method comprising the steps of:
printing the thermosetting resin composition according to claim 2 so as to cover at least a portion of a wiring pattern of the flexible wiring board, the wiring pattern being subjected to a Sn plating processing in advance; and
curing the printed thermosetting resin composition to form a protective film.

7. A flexible wiring board comprising a protective film formed by the method according to claim 6 .

8. A method for forming a protective film for a flexible wiring board, the method comprising the steps of:
printing the thermosetting resin composition according to claim 3 so as to cover at least a portion of a wiring pattern of the flexible wiring board, the wiring pattern being subjected to a Sn plating processing in advance; and
curing the printed thermosetting resin composition to form a protective film.

9. A flexible wiring board comprising a protective film formed by the method according to claim 8 .

10. The thermosetting resin composition according to claim 1 , wherein said constitutional unit derived from an alicyclic diol includes a constitutional unit derived from cyclohexanedimethanol.

11. The thermosetting resin composition according to claim 1 , wherein said constitutional unit derived from an alicyclic diol includes a constitutional unit derived from 1, 4-cyclohexanedimethanol.

12. The thermosetting resin composition according to claim 1 , wherein said constitutional unit derived from an alicyclic diol includes a constitutional unit derived from five-membered ring diols and six-membered ring diols.

13. The thermosetting resin composition according to claim 12 , wherein the polyurethane resin further comprises a constitutional unit derived from an aliphatic diol.

14. The thermosetting resin composition according to claim 2 , wherein the polyurethane resin has a carboxyl group or an acid anhydride group at an end of a molecule thereof.

15. The thermosetting resin composition according to claim 1 , said composition having a viscosity of 20 Pa·s to 80 Pa·s.

16. A cured product of the thermosetting resin composition according to claim 1 .

17. The thermosetting resin composition according to claim 1 , wherein the polyurethane resin has a number average molecular weight of 5000 to 65000.

18. The thermosetting resin composition according to claim 1 , wherein the alicyclic diol comprises at least one of 1,4-cyclohexane diol and 1,4-cyclohexane dimethanol.

19. The thermosetting resin composition according to claim 1 , wherein the polyurethane resin has been synthesized by:
reacting a diol including a polycarbonatediol having a constitutional unit derived from an alicyclic diol with a polyisocyanate having an isocyanate group to obtain a polyisocyanate having a urethane linkage, and reacting the polyisocyanate having the urethane linkage with an acid anhydride; or
reacting a diol including an alicyclic diol or a polycarbonatediol having a constitutional unit derived from an alicyclic diol and a dihydroxy compound having a carboxyl group with a polyisocyanate having an isocyanate group.

20. The thermosetting resin composition according to claim 1 , wherein the curing agent is included in an amount of 1 to 30 mass% of a total mass of the polyurethane resin.

21. The thermosetting resin composition according to claim 1 , wherein the polyurethane resin has been synthesized by reacting a diol including an alicyclic diol or a polycarbonatediol having a constitutional unit derived from an alicyclic diol with a polyisocyanate having an isocyanate group to obtain a polyisocyanate having a urethane linkage, and reacting the polyisocyanate having the urethane linkage with an acid anhydride.

22. The thermosetting resin composition according to claim 1 , wherein the polyisocyanate having an isocyanate group comprises a isocyanate compound represented by the following formula (4):
OCN—X—NCO  (4)

wherein X represents a divalent organic group.

23. The thermosetting resin composition according to claim 1 , wherein the thermosetting resin composition comprises a property of providing a flexible copper-clad laminate plate having an MIT Flexibility-1 of 60 cycles or more, when the thermosetting resin is used to form a cured protective film having a thickness of 10 μm on the flexible copper-clad laminate plate comprising a polyimide film having a thickness of 38 μm, a comb-like copper foil wiring pattern having a thickness of 8 μm formed on the polyimide film, and a tin plating layer having a thickness of 0.2 to 0.3 μm formed on the copper foil.

24. The thermosetting resin composition according to claim 1 , wherein the polyurethane resin has an acid value of 10 to 28 mgKOH/g.

Assignees

• Hukushima Iori
• Hirata Tomohiro
• Kondou Hidekazu
• Kaneko Susumu
• Uehara Satoshi
• Miyamoto Yuki
• Hitachi Chemical Co Ltd

Inventors

• Hukushima Iori
• Hirata Tomohiro
• Kondou Hidekazu
• Kaneko Susumu
• Uehara Satoshi
• Miyamoto Yuki

Classifications

• C08G18/00

  Polymeric products of isocyanates or isothiocyanates · CPC title

• C08G18/6438

  Polyimides or polyesterimides · CPC title

• C08G18/6633

  Compounds of group C08G18/42 · CPC title

• C08G18/3212

  containing cycloaliphatic groups · CPC title

• C08G18/0823

  containing carboxylate salt groups or groups forming them · CPC title