JPH0464799B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to cream solder. Cream solder is a creamy solder made by dispersing powdered solder in a flux containing rosins, activators, solvents, suitable viscosity modifiers, and other additives. This is mainly used by coating or printing on metal substrates to be bonded. Therefore, the performance required for cream solder is
In addition to the performance required for general solder flux such as safety for the human body, good solderability, high insulation, non-corrosion, and no deterioration during storage, it also has excellent printing characteristics and post-soldering cleanability. It is particularly required that In particular, when cream solder is used for precision electronic components, it is necessary that it has excellent ejection properties during printing, that it ejects better than a screen plate or nozzle, and that the ejected material does not bleed or sag. A certain level of fluidity is required in order to have good dispensing properties, but if the fluidity is high, it will cause bleeding or sagging, so it is important for cream solder to have viscosity characteristics that satisfy both. is important. Conventionally, in order to obtain cream solder having such properties, a suitable viscosity modifier is added to the flux. For example, ester-based substances; hydrogenated oils such as coconut oil, beef tallow, castor oil, whale oil, rapeseed oil, semi-hardened oils, wood wax, beeswax, candelilla wax, carnauba wax, etc.; free acids; adipic acid, corkic acid; , azelaic acid, sebacic acid, dodecanedioic acid,
Myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, coconut oil fatty acid, tallow fatty acid, rapeseed oil fatty acid, montanic acid, polyethylene glycolic acid, benzoic acid, phthalic acid, trimellitic acid, etc. and inorganic or organic extender pigments; for example bentonite , organic bentonite, ultrafine silica,
Ultrafine powder alumina, aluminum stearate, etc. have been used. However, the above-mentioned ester-based substances have insufficient cleanability after soldering, and also tend to inhibit the wetting of molten solder onto the metal substrate, leading to the formation of solder balls and deteriorating solderability. Acids do not have sufficient thixotropy, so they tend to cause bleeding or sagging without improving ejection performance during printing, and organic or inorganic extender pigments inhibit the wetting of molten solder onto metal substrates. At the same time, it also worsens the flow of solder and causes the generation of solder balls. In order to enable precision soldering of minute parts, the present inventors have developed a cream solder that has advanced printing and dispensing characteristics, good solderability, and aims to shorten the cleaning process. As a result, the inventors discovered that it is possible to produce cream solder having excellent cleanability and viscosity characteristics by incorporating a specific amide into the flux of cream solder, and completed the present invention. That is, the present invention provides a cream solder comprising solder, a rosin, an activator, a solvent, and a flux containing at least a viscosity modifier, in which the viscosity modifier is at least one unsaturated alkyl group or hydroxyl group having 16 to 24 carbon atoms. A cream solder containing an amide having an unsaturated alkyl group or a hydroxyl group-containing saturated alkyl group is provided. Examples of the amide having an unsaturated alkyl group having at least 16 to 24 carbon atoms used in the present invention include unsaturated carboxylic acid amides. Preferably, oleic acid amide, elaidic acid amide,
Examples include gadoleic acid amide, erucic acid amide, brassic acid amide, ceracoleic acid amide, linoleic acid amide, linolenic acid amide, and eleostearic acid amide. Particularly preferred is oleic acid amide. The present invention is not limited to the above-mentioned typical amides, but may be any amide having an unsaturated alkyl group having at least 16 to 24 carbon atoms.
For example, N-substituted products of the above-mentioned amides, so-called bisamides obtained by the reaction of an unsaturated carboxylic acid having 16 to 24 carbon atoms with a diamine, or a reaction product of an amine having the above-mentioned carbon skeleton with an acid may be used. good.
Preferred examples of these include N-oleyl stearamide, N-oleyl oleamide, N-stearyl oleamide, N-oleyl palmitic acid amide, ethylenebisoleic acid amide, hexamethylenebisoleic acid amide, N, N'-dioleyladipic acid amide, N,
N'-dioleylsebacic acid amide, or N,
Examples include N'-dioleylphthalic acid amide.
In all of these examples, materials having an oleic acid carbon skeleton were used, but elaidic acid and other carbon skeletons can be similarly used. Some of these amides have a higher melting point than monoamides, and although they improve the viscoelastic temperature stability of the resulting cream solder, their increased molecular weight and melting point reduce the cleanability. It is preferable to reduce the amount of addition. Typical examples of the unsaturated amide containing at least one hydroxyl group having 16 to 24 carbon atoms include ricinoleic acid amide, oxynarbonic acid amide, and camolenic acid amide. Particularly preferred is ricinoleic acid amide, which exhibits good thixotropy and detergency. Further, like the above-mentioned amides having an unsaturated alkyl group, N-substituted products, bisamides, etc. can also be used. Examples of these include N-ricinoleyl ricinoleic acid amide, ethylene bisricinoleic acid amide, N,N'-diricinoleyl adipic acid amide, N,N'-diricinoleyl sebacic acid amide, N,N'- Examples include diricinoleyl phthalic acid amide. The amount added is the same as that for the amide having an unsaturated alkyl group. A typical example of an amide having at least one hydroxyl group-containing saturated alkyl group having 16 to 24 carbon atoms is an aliphatic oxycarboxylic acid amide, which has one or more hydroxyl groups and an unsaturated group. It is something that does not happen. Examples of such hydroxy saturated carboxylic acid amides are 12-hydroxystearamide, 2-hydroxypalmitic acid amide, 2-hydroxystearic acid amide, 2-hydroxystearic acid amide,
Hydroxyarachidic acid amide, 2-hydroxybehenic acid amide, 2-hydroxylignoceric acid amide, fatty acid amide of hydrogenated castor oil, amide of oxides of oleic acid, linoleic acid or linolenic acid, 12-hydroxystearic acid amide, 9,10
-dihydroxystearamide, 9,10,12
-trihydroxystearic acid amide, 9,10,
12,13-tetrahydroxystearamide, etc. A particularly preferred hydroxy saturated carboxylic acid amide is 12-hydroxystearic acid amide. Of course, like the above-mentioned amides, bisamide,
Other derivatives containing N-substitutions may also be used. Examples of these include methylene bis-12-hydroxystearamide, ethylene bis-12-hydroxystearamide, N-oleyl-12-
Hydroxystearamide, N-stearyl-12-hydroxystearamide, hexamethylenebis-12-hydroxystearamide, 12-hydroxystearoyl-12-hydroxystearamide, ricinoleyl-12-hydroxystearamide, 12- Hydroxystearoyloleic acid amide, N,N'-di-12-
Hydroxystearoyl adipamide, N,
N'-di-12-hydroxystearoylsebacic acid amide, N,N'-di-12-hydroxystearoyl phthalic acid amide, N,N'-di-12-hydroxystearoylmaleic acid amide, N,
Examples include N'-di-12-hydroxystearoylmalonic acid amide and N,N'-di-12-hydroxystearoylsuccinic acid amide. Of course 12
The structure is not limited to the -hydroxystearic acid skeleton, and other typical acid skeletons mentioned above may also be used. The amount added is also the same as that for the above-mentioned amides. These are about 1 to about 20 based on the weight of flux.
%, preferably 5-10%. An amide having an alkyl group having less than 16 carbon atoms has a low melting point and does not have a sufficient viscosity adjusting effect. Also, amides with more than 24 carbon atoms lack industrial practicality. When the amide of the present invention is blended into a flux as a viscosity modifier for cream solder, if there is a hydroxyl group, the hydroxyl group in the molecule interacts with a relatively long carbon chain and a free carboxyl group to generate hydrogen. It forms a cohesive gel, giving it very high thixotropy. Further, the above-mentioned amides precipitate in the cream solder and become fine fillers, exhibiting good characteristics. However, amides of saturated fatty acids that do not have hydroxyl groups, such as stearic acid amide, do not have sufficient detergency because they do not have hydroxyl groups or double bonds. If the amount of the amides of the present invention is less than 1% of the total flux, the above effect will be insufficient, and if it is more than 20%, good viscosity properties will not be obtained. Therefore, when the performance required for the cream solder is well suited to the solderability, high insulation, non-corrosion, etc. obtained by the amides of the present invention, it is possible to use the rosin compounded in the flux instead of the rosin compound, or It may be used in place of a part of it. When the amides of the present invention are used as a thickener, the solderability of the cream solder is significantly improved without impairing its non-corrosive properties and high insulation properties, and it is also soluble in chlorine-based or fluorocarbon-based cleaning agents. This improves the ease of cleaning after soldering. Examples 1 to 15 and Comparative Examples 1 to 10 Fluxes were prepared according to the respective formulations shown below, and then 87% of more than 250 meshes of powdered solder and 13% of the flux were kneaded to obtain cream solder. Table 1 shows the performance of the obtained cream solder. Example 1 % by weight oleic acid amide 12 Polymerized rosin 54.5 Diethylene glycol monobutyl ether 31 Hydrogenated castor oil 1.5 Diethylamine hydrobromic acid 1 Example 2 % by weight ricinoleic acid amide 12 Polymerized rosin 54 Diethylene glycol monobutyl ether 33 Diethylamine hydrobromic acid 1 Example 3 % by weight 12-hydroxystearamide 12 Polymerized rosin 54 Diethylene glycol monobutyl ether 33 Diethylamine hydroxybromic acid 1 Example 4 % by weight Ethylene bisoleic acid amide 12 Polymerized rosin 52.5 Diethylene glycol monobutyl ether 33 Hydrogenated castor oil 1.5 Diethylamine odor Hydrohydric acid 1 Example 5 % by weight ethylene bisricinoleic acid amide 10 Polymerized rosin 53 Diethylene glycol monobutyl ether 36 Diethylamine hydrobromic acid 1 Example 6 % by weight Ethylene bis-12-hydroxystearic acid amide 7 Polymerized rosin 57 Diethylene glycol monobutyl ether 37 Diethylamine odor Hydrohydric acid 1 Example 7 % by weight N-oleyl stearamide 15 Polymerized rosin 48 Diethylene glycol monobutyl ether 36 Diethylamine hydrobromic acid 1 Example 8 % by weight N,N'-dioleyladipate amide 10 Polymerized rosin 53.5 Diethylene glycol mono Butyl ether 34 Hydrogenated himin oil 1.5 Diethylamine hydrobromide 1 Example 9 % by weight N,N'-dioleylphthalic acid amide 8 Polymerized rosin 55 Diethylene glycol monobutyl ether 36 Diethylamine hydrobromide 1 Example 10 % by weight N-oleyl 12 -Hydroxystearamide
15 Polymerized rosin 47 Diethylene glycol monobutyl ether 37 Diethylamine hydrobromide 1 Example 11 % by weight N,N'-dilicinoyleradipic acid amide 10 Polymerized rosin 53 Diethylene glycol monobutyl ether 36 Diethylamine hydrobromide 1 Example 12 % by weight N , N'-diricinoleyl phthalic acid amide 8 Polymerized rosin 55.5 Diethylene glycol monobutyl ether 34 Hydrogenated castor oil 1.5 Diethylamine hydrobromide 1 Example 13 % by weight N-stearyl 12-hydroxystearic acid amide 10 Polymerized rosin 53 Diethylene glycol monobutyl ether 36 Diethylamine hydrobromide 1 Example 14 % by weight N,N'-di12-hydroxystearoylsebacic acid amide 10 Polymerized rosin 52 Diethylene glycol monobutyl ether 37 Diethylamine hydrobromide 1 Example 15 % by weight N,N'-di12 -Hydroxystearoyl phthalic acid amide 8 Polymerized rosin 54 Diethylene glycol monobutyl ether 37 Diethylamine hydrobromide 1 Comparative example 1 % by weight hydrogenated castor oil 5 Polymerized rosin 60 Diethylene glycol monobutyl ether 34 Diethylamine hydrobromide 1 Comparative example 2 % by weight Stearic acid amide 13 Polymerized rosin 55 Diethylene glycol monobutyl ether 31 Diethylamine hydrobromide 1 Comparative example 3 % by weight ethylene-bis-stearamide 11 Polymerized rosin 55 Diethylene glycol monobutyl ether 31 Diethylamine hydrobromide 1 Comparative example 4 % by weight hydrogenated castor oil 4 Polymerized Rosin 40 Diethylene glycol monobutyl ether 26 Hydroabiethyl alcohol 29 Diethylamine hydrobromide 1 Comparative example 5 % by weight hydrogenated castor oil 4 Polymerized rosin 45 Diethylene glycol monobutyl ether 23 Methylhydroabietate 27 Diethylamine hydrobromide 1 Comparative example 6 % by weight Stearin Acid amide 10 Hydrogenated castor oil 2 Polymerized rosin 35 Diethylene glycol monobutyl ether 32 Hydroabiethyl alcohol 20 Diethylamine hydrobromide 1 Comparative example 7 % by weight stearic acid amide 10 Hydrogenated castor oil 2 Polymerized rosin 38 Methylhydroabietate 25 Diethylene glycol monobutyl ether 24 Diethylamine hydrobromide 1 Comparative example 8 % by weight coconut oil fatty acid acid amide 10 Hydrogenated castor oil 2 Polymerized rosin 38 Methylhydroabietate 25 Diethylene glycol monobutyl ether 24 Diethylamine hydrobromide 1 Comparative example 9 % by weight hydrogenated beef oil fatty acid amide 10 Hydrogenated castor oil 2 Polymerized rosin 38 Methylhydroabietate 25 Diethylene glycol monobutyl ether 24 Diethylamine hydrobromide 1 Comparative example 10 % by weight hydrogenated beef oil fatty acid amide 10 Hydrogenated castor oil 2 Polymerized rosin 38 Methylhydroabietate 20 Diethylene glycol monobutyl ether 24 Organic acid (sebacic acid) 4 Antioxidant (BHT) 0.5 Antifoaming agent (silicone oil) 0.5

【table】

[Table] ◎: Excellent, ○: Good, △: Fair, ×: Impossible

Claims (1)

[Claims] 1. A cream solder consisting of solder and a flux containing at least a rosin, an activator, a solvent, and a viscosity modifier, in which at least one viscosity modifier is present.
A cream solder containing an amide having one unsaturated alkyl group having 16 to 24 carbon atoms, an unsaturated alkyl group containing a hydroxy group, or a saturated alkyl group containing a hydroxy group. 2. The cream solder according to item 1, which contains amide in an amount of 1 to 20% by weight based on the total flux. 3 Amide having at least one unsaturated alkyl group having 16 to 24 carbon atoms is oleic acid amide, N-
Oleyl stearamide, N-oleyl oleic acid amide, N-stearyl oleic acid amide, N-oleyl palmitic acid amide, ethylenebisoleic acid amide, hexamethylenebisoleic acid amide, N,N'-dioleyladipic acid amide, N,N'-dioleylsebacic acid amide,
or the cream solder according to item 1, which is N,N'-dioleylphthalic acid amide. 4 The amide having at least one hydroxy group-containing unsaturated alkyl group having 16 to 24 carbon atoms is ricinoleic acid amide, N-ricinoleyl ricinoleic acid amide, ethylenebisricinoleic acid amide,
N,N'-diricinoleyl adipate amide, N,
N'-diricinoleyl sebacic acid amide or N,
The first one is N'-diricinoleyl phthalic acid amide.
Cream solder as described in section. 5 The amide having at least one hydroxy group-containing saturated alkyl group having 16 to 24 carbon atoms is 12-hydroxystearamide, ethylene bis-12
-Hydroxystearamide, N-oleyl-12-hydroxystearamide, N-stearyl-12-hydroxystearamide, methylenebis-12-hydroxystearamide, ethylenebis-12-hydroxystearamide, hexamethylenebis -12-hydroxystearic acid amide, 12-hydroxystearoyloleic acid amide, N,N'-di-12-hydroxystearoyladipic acid amide, N,N'-di-12-hydroxystearoylsebacic acid amide, N,N' -di-12-hydroxystearoyl phthalic acid amide, N,N'-di-12-hydroxystearoyl maleic acid amide, N,N'-di-
12-hydroxystearoylmalonic acid amide,
2. The cream solder according to item 1, which is N,N'-di-12-hydroxystearoylsuccinimide.