The indiscriminate use of beauty products, such as hand lotions or creams, throughout your company may be responsible for those undefined solderability problems you are having.

By: Richard Rich

Do you know that hand care products have been developed exclusively for the electronic industry which eliminate this problem?

Skin care products are normally associated with the cosmetic industry only, and are seldom, if ever, considered as having an effect on electronic manufacturing. Nothing could be further from the truth. Circuit contamination resulting from the use of skin care products can be devastating to the solderability of an electronic assembly.

It is a well understood fact that the life expectancy and intended function of an electronic assembly depends heavily on the reliability of its soldered connections. One faulty solder joint can cause the entire assembly to malfunction. Problems created by poor soldering are very time consuming and expensive to locate and repair.

There are many factors involved in producing a quality solder connection; however, the condition of the surfaces to be joined is one of the most important. These surfaces must be clean and free of contamination. Because this critical soldering operation normally takes place in the final phases of manufacturing, much time and money must be spent in an effort to control contamination of parts to be soldered in the prior assembly stages. All of these precautions can be wasted if the possibility of hand lotion contamination is overlooked. Although flux is an intricate part of all soldering operations and is used for the purpose of cleaning the surfaces to be joined, its cleaning ability should not be overestimated. The types of flux most often used in electronics is derived from rosin. The rosin family of fluxes are the safest to use but are relatively poor cleaners. Their intended purpose is to remove minor oxidation only. Therefore, they cannot be relied on for removing contamination due to the mishandling of components by any means, including the use of undesirable skin care products.

Almost everyone uses skin care products in one form or another. Conventional products of this type are formulated using substantial amounts of silicone, lanolin, and mineral oil. These are all well-known deterrents to solderability. When found in products familiar to electronic manufacturing, such as silicone grease and machine oils, they are recognized as potential problems. Every effort possible is made to prevent their coming in contact with a surface to be soldered. However, when these same materials are found in skin care products; they are often overlooked as being the same type of hazard.

Although silicone, lanolin and mineral oil are the most common types of contaminates found in hand lotions or creams, they are by no means the only ones. Other ingredients that cause solderability problems are the wide variety of vegetable and animal fats used in these products. The problems they cause vary in severity with the type and amount of undesirable ingredients the lotion contains, as well as with the frequency they are applied. Fortunately, there have been products developed which safely address this problem. IC Lotion, developed and manufactured by R & R Lotion of Tempe, Arizona, is just such a product.

The material contains absolutely nothing that will, in any way, detract from the solderability of the parts handled while using it. It is also free of corrosion forming chlorides, which can impede the electrical function of equipment.

The line operators are generally the major contributor to surface contamination, because of their intimate contact with the components of an assembly. However, they are not the only culprit. Any person who has the opportunity to come in contact with the parts are suspect. This ranges from stock handlers to managers and anywhere in between … even just curious office personnel who may inadvertently handle the parts of an assembly. The one thing they have in common is that they are all probably using conventional skin care products in one form or another and are leaving contaminating residue on the circuits.

Because every employee is a potential threat to solderability in this respect, lotions have been made available in a variety of sizes and methods of dispensing for easy accessibility to all employees. The 8 oz. size is ideal for individual use and can be stored easily at a workstation or desk. Wall dispensers are available for placement at convenient locations throughout the plant.

Circuit contamination due to hand contact is not limited, unfortunately, to just the use of conventional hand care products. Often food contamination is just as severe a problem. For example, the residue of potato chips contains oils and salts which are corrosive and impede solderability. There is also a wide variety of other contaminates which can be picked up on the hands and transmitted to the circuits. Assembly personnel must be encouraged to keep their hands clean; however, this is very difficult to control and must be the responsibility of the individual. The harsh hand soaps that are provided in most manufacturing facilities have such a drying effect on the hand that they actually discourage thorough hand cleaning. The placing of lotion dispensers next to the soap dispensers should help solve this problem.

In the continual battle to preserve component solderability, the exclusive use of a completely safe product, like IC Lotion, can eliminate at least one of these areas of concern. This is more than sufficient reason to motivate a company into supplying ample amounts of this product for its employees’ use.

However, product safety and ample supply are not always sufficient reasons to guarantee the exclusive use of a product by the individual. The only reason a person uses this type of product is to relieve a rough, red, irritated skin condition. If a product doesn’t perform well in this area; they will migrate back to using one of the conventional products that will.

So, when choosing a non-contaminating lotion, consideration must be made to select a formulation that will meet the criteria of non-contamination yet be an excellent Skin care product