Amine, carboxylic acid flux composition and method of soldering

1. A flux composition comprising, as initial components:

a carboxylic acid; and,

an amine fluxing agent represented by formula I:

wherein R 1 , R 2 , R 3 and R 4 are independently selected from a hydrogen, a substituted C 1-80 alkyl group, an unsubstituted C 1-80 alkyl group, a substituted C 7-80 arylalkyl group and an unsubstituted C 7-80 arylalkyl group; wherein R 7 and R 8 are independently selected from a C 1-20 alkyl group, a substituted C 1-20 alkyl group, a C 6-20 aryl group and a substituted C 6-20 aryl group or wherein R 7 and R 8 , together with the carbon to which they are attached, form a C 3-20 cycloalkyl ring optionally substituted with a C 1-6 alkyl group; wherein R 10 and R 11 are independently selected from a C 1-20 alkyl group, a substituted C 1-20 alkyl group, a C 6-20 aryl group and a substituted C 6-20 aryl group or wherein R 10 and R 11 , together with the carbon to which they are attached, form a C 3-20 cycloalkyl ring optionally substituted with a C 1-6 alkyl group; and, wherein R 9 is selected from a hydrogen, a C 1-30 alkyl group, a substituted C 1-30 alkyl group, a C 6-30 aryl group and a substituted C 6-30 aryl group.

2. The flux composition of claim 1 , wherein the carboxylic acid is selected from the group consisting of a C 8-80 aliphatic mono carboxylic acids; C 2-20 aliphatic dicarboxylic acids; C 6-20 aromatic carboxylic acids; and, mixtures thereof.

3. The flux composition of claim 2 , wherein the carboxylic acid is selected from the group consisting of octanoic acid; nonanioc acid; undecanoic acid; dodecanoic acid; tridecanoic acid; tetradecanoic acid; pentadecanoic acid; hexadecanoic acid; heptadecanoic acid; stearic acid; hydroxy stearic acid; oleic acid; linoleic acid; α-linolenic acid; icosanoic acid; oxalic acid; malonic acid; succinic acid; malic acid; glutaric acid; adipic acid; pimelic acid; suberic acid; benzoic acid; phthalic acid; isophthalic acid; terephthalic acid; hemimellitic acid; trimellitic acid; trimesic acid; mellophanic acid; prehnitic acid; pyromellitic acid; mellitic acid; toluic acid; xylic acid; hemellitic acid; mesitylene acid; prehnitic acid; cinnamic acid; salicylic acid; benzoic acid; naphthoic acid; phenolphthalin; diphenolic acid and mixtures thereof.

4. The flux composition of claim 1 , wherein the flux composition exhibits a fluxing agent amine nitrogen to carboxylic acid acid content (—COOH) equivalent ratio of 1:1 to 20:1.

5. The flux composition of claim 1 , wherein the substitutions in the substituted C 1-80 alkyl group and the substituted C 7-80 arylalkyl group, from which R 1 , R 2 , R 3 and R 4 are selected, are selected from at least one of an —OH group, an —OR 5 group, a —COR 5 -group, a —COR 5 group, a —C(O)R 5 group, a —CHO group, a —COOR 5 group, an —OC(O)OR 5 group, a —S(O)(O)R 5 group, a —S(O)R 5 group, a —S(O)(O)NR 5 2 group, an —OC(O)NR 6 2 group, a —C(O)NR 6 2 group, a —CN group, a —N(R 6 )-group and a —NO 2 group; wherein R 5 is selected from a C 1-28 alkyl group, a C 3-28 cycloalkyl group, a C 6-15 aryl group, a C 7-28 arylalkyl group and a C 7-28 alkylaryl group; wherein R 6 is selected from a hydrogen, a C 1-28 alkyl group, a C 3-28 cycloalkyl group, a C 6-15 aryl group, a C 7-28 arylalkyl group and a C 7-28 alkylaryl group.

6. The flux composition of claim 1 , wherein R 1 , R 2 , R 3 and R 4 are independently selected from a hydrogen, a —CH 2 CH(OH)R 18 and a —CH 2 CH(OH)CH 2 —O—R 18 group; wherein R 18 is selected from a hydrogen, a C 1-28 alkyl group, a C 3-28 cycloalkyl group, a C 6-28 aryl group, a C 7-28 arylalkyl group and a C 7-28 alkylaryl group; wherein R 7 and R 8 are both a methyl group; wherein R 10 and R 11 are both a methyl group; and, wherein R 9 is selected a methyl group and a phenyl group; and wherein zero to three of R 1 , R 2 , R 3 and R 4 is(are) hydrogen.

7. The flux composition of claim 3 , wherein zero to three of R 1 , R 2 , R 3 and R 4 is(are) hydrogen.

8. The flux composition of claim 1 , further comprising, as initial components:

0 to 95 wt % of a solvent,

0 to 30 wt % of a thickening agent,

0 to 30 wt % of a thixotropic agent, and

0 to 30 wt % of an antioxidant.

9. The flux composition of claim 1 , further comprising: a solder powder.

10. A method of applying solder to an electrical contact, comprising:

providing an electrical contact;

providing a flux composition according to claim 1 ;

applying the flux composition to the electrical contact;

providing a solder;

melting the solder; and,

displacing the flux composition applied to the electrical contact with the molten solder;

wherein the molten solder makes physical contact with the electrical contact and bonds to the electrical contact.