The definition of pre-spotting is spotting before wetcleaning. The purpose is to remove staining and soil not removed by the ordinary wetcleaning process. It is used to save time and avoid cleaning the garment or fabric again.
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More pre-spotting is needed on oil-based stains since the wetcleaning process does not react well on oil-based stains.
The major consideration in pre-spotting is the chemistry of the wetcleaning process you are using. The pre-spotting procedure must be compatible with the wetcleaning detergent used.
Wool and silk
To maintain a soft feel and reduce shrinkage, cationic detergents are used for wetcleaning. Cationic detergents carry a positive ionic charge.
If an anionic-based spotting agent is used, there will be a breakdown of the agents producing rings and swales.
The cationic detergent and the anionic lubricant counteract each other causing a breakdown.
The second consideration is the alkalinity of the spotting agents. Ammonia and alkali found in protein formulas can damage the dye on wool and silk. It is therefore important to approach protein and albuminous staining with digesters and spotting formulas with a nonionic lubricant.
Protein stains. Protein stains originate from the body. These stains include blood, milk, eggs, perspiration and urine.
Cleaners Chemical Corp. makes a digestive spotting agent with a nonionic lubricant. This is safe to wool and is compatible with the cationic detergents.
Laidlaw makes a powdered enzyme (RSR) which is also effective and safe for pre-spotting wool and silk.
Other manufacturers may have comparable products, but ask the sales representative if the formulation has a nonionic lubricant present.
Tannin stains. These are stains originating from vegetable matter. This includes liquor, soft drinks, wine, tea, coffee and catsup.
The acid formulation of most tannin formulas is safe to wool and silk provided the agent contains a nonionic lubricant.
Cleaners Chemical Corp makes Lube-Remove. Check with other chemical companies for similar formulations.
To make a safe tannin formula for wools and silks, you can mix 28% acetic acid with the cationic detergent used for wetcleaning. Mix four parts water, one part detergent and one part acetic.
Dryside stains. These are stains such as oil, grease, paint, nail polish and lipstick. Do not use a drycleaning oily type paint remover or amyl acetate for pre-spotting.
Paint removers may contain hydrocarbon or perchloroethylene solvent. Pre-spotting runs the risk of water contamination with solvent that is a violation of EPA regulations.
Cleaners Chemical Corp, Laidlaw/ADCO, A. L. Wilson Chemical and others make a nonionic based lubricant that is effective for dryside stains.
Although relatively safe, nonionic spotting agents can affect the sheen and dye on some silks.
They are also not effective on plastic-based stains such as paint, nail polish and glue. This means that these plastic based stains should be handled in drycleaning.
Soil. For pre-spotting heavy soil on wools and silks, use a formulation with a nonionic base or concentrated cationic detergent mixed with water.
Cotton, linen and polyester
These fabrics have more leeway in pre-spotting. The detergents used are anionic based which have a negative ionic charge.
Protein stains. All protein formulas can be used for spotting. This includes spotting formulations with either anionic or nonionic lubricant. It is also permissible to use protein formulas with an alkali or ammonia based mixtures.
Tannin stains. Any formulation can be used. This means any tannin formulation or any lubricant mixed with acetic acid. The only exclusion is mixing it with a cationic detergent.
Dryside stains. Use nonionic based detergents on cottons and linen. The nonionic formulation can be mixed with a little ammonia to make is more aggressive. On bright and vivid colors test the color for safety.
Soil. An alkaline based lubricant can be used to remove ground-in soil before wetcleaning.
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