The drycleaning procedures do not vary from perc cleaning other than there is not nearly as much chance of a dye migration or dye bleeding from garments. It is also rare that a garment cleaned in hydrocarbon solvent will damage or destroy beads or sequins. Therefore, classification is more by garment weight and drying time than color of garments however, classification will take into consideration the amount of soil a garment contains.
Garments can come just as clean in hydrocarbon solvent as any other and have the added benefits of being completely odorless, generally brighter with reduced wrinkling and easier to press or finish with a softer hand.
Classification may consist of several categories such as regular, silks, whites, reds, hard-to-clean and household items. The bulk of the garments will fall into the “regular” category. The next will be “silks” or most anything a lady would wear. “Whites” may want to be cleaned alone to reduce the chance that redeposition may occur from heavily soiled garments, short cycle times, inadequate detergent or moisture or tainted solvent. “Reds” should always be suspect for bleeding and cleaned by themselves. As mentioned before, hydrocarbon is much less aggressive to dyes and has much less bleeding than perc.
“Hard-to-Clean” garments will have a longer wash time than regular garments and may require more prespotting or moisture additions to the solvent. “Household” textiles are a natural for hydrocarbon cleaning due to its lightweight when compared to perc. The weight of hydrocarbon solvent is approximately 6.5 pounds per gallon compared to 13.5 for perc. The weight of the solvent adds to its mechanical action and normally a minimum of mechanical action is needed for household textiles.
Proper minimum cleaning times for excellent cleaning in hydrocarbon solvent is 22 min. for Regular loads, 11 minutes for Silks, 5 minutes for Reds, while Hard-to-Clean will require 30 minutes of wash time, or longer depending upon soil content and amount. Household items can vary from simply flushing solvent through them to perhaps 5 to 7 minutes on reduced agitation…including reduced tumbling time in drying.
Anionic detergents (the greasy feeling ones) are frequently used with hydrocarbon solvents. As a rule they contain little to no moisture and moisture must be added for optimum cleaning results. Cationic detergents usually have a water base and no additional moisture is needed. Anionic detergents may be used as a charge of about 1% or, 1 gallon of detergent for each 100 gallons of new or distilled solvent. Cationic detergents are injected during a “milling” bath or “pre-bath.” The machine is started and the solvent flows from the base tank to the wash wheel while bypassing the filter for about four to five minutes then the solvent is sent through the filter and back to the wash wheel for an additional 17 minutes. Whites may be cleaned from the solvent of a tank reserved only for whites and reds may be washed in the regular cleaning solvent then dumped directly to the still after cleaning, either on or off filter. There are numerous combinations of cycles that may be used with hydrocarbon, or any other type of cleaning.
For prespotting, the solution is easy and inexpensive to make. The desired mix of new or distilled hydrocarbon solvent is approximately a 15% detergent solution and the easiest way to make it is get a clean gallon jug and add 15 or 16 ounces of anionic (drycleaning) detergent then fill the jug up with new or distilled solvent. This is good for an all around dry (meaning no water) prespotter. It can be used on anything that is drycleanable. Simply apply to the soiled area with a squirt bottle or a brush dipped in the mixture then apply to the soiled area and either tamp or brush lightly. This also makes an excellent leveling agent and is also called a slop spotter, for obvious reasons.
If the stained or soiled area is water soluble then the above procedure may be used then add just a small amount of steam from the steam gun held about 12 inches above the garment. Just enough to slightly dampen the area where the prespotting mixture was applied.
For moisture addition to the solvent a good mixture is the compatible prespotter for the detergent being used and mix according to directions on the prespotter bottle. The mix is usually four or eight to one with water. After this is mixed then two ounces for every ten pounds of cleaning is added to the wash wheel before putting the clothes in or putting it in the button trap. For a forty-pound load, this would be a total of eight ounces of the moisture addition per load. I have used this same ratio for all loads including wools, whites and households. The brightness to the garments this produces is quite noticeable along with reduced body odors and food stains.
As a rule, the length of time in the wash cycle is double the time for perc. The extract is at a much higher speed than a heavier solvent and is necessary because the solvent is harder to remove from the garments and will greatly reduce the drying time.
Checking for when the garments are dry is a bit different with the odorless hydrocarbon, as you can’t smell the solvent. The best way of telling if the garments are dry is to reach inside of the garment and squeeze a shoulder pad or other multiple layer of fabric. If the garment is not dry then there will be a trace of the solvent on your hand. Since it takes a lot of airflow during the dry cycle it is mandatory that the lint filters be kept clean at all times. Sometimes it is necessary to clean them after every load if there is a lot of lint being removed from the garments.
What About the Odor?
There are many misconceptions regarding hydrocarbon solvent and the main one is that all the garments will stink due to a bacteriological growth that cannot be prevented. It is true that if hydrocarbon solvent is not kept clean and the water separator is not kept maintained then bacteria can grow and it can become quite odorous.
Since hydrocarbon and water are about the same weights, or densities, it takes time and a larger water separator to keep the two apart. If water is allowed to build-up in the solvent, an odor will likely occur. When it does happen it is not fun to clean up the mess that you have allowed to develop. Bacteria will grow and develop by eating the oils and greases (Non-volatile Residue) in the solvent then pooping, and it is the poop that gives the rancid smell, not the poor little bacterium.
The prevention is fairly easy. At least once a week empty and clean the water separator with a mild solution of chlorine bleach (two ounces of chlorine bleach per gallon of water). Keep your solvent free of excess NVR either through distillation or the use of Tonsil filter aid in a spin disk filter.
Tips and Tricks
The best tip I can give you is to keep the solvent clean, use a moisture addition to each load cleaned and to not over use detergent.
It goes without saying that when spotting before cleaning the chemicals should never be “flushed” out during the cleaning cycle. The drycleaning machine is not a toilet and should not be used as one. Spotting chemicals should always, always be flushed out at the spotting board and dried before cleaning. Every time, no exceptions!
If solvent is kept clean then bacteria odors are not going to be a problem. Solvent is kept clean through distillation at the proper temperature and never more than is necessary to boil the solvent. The alternative method is by using a spin disk filter and Tonsil filter aid to remove dyes, oils and greases (NVR), moisture and odors that may find their way into the solvent.
Too much detergent and a high boiling temperature while distilling will lead to some of the detergent (NVR) being carried over with the distillate. When this occurs it is almost impossible to mechanically separate the moisture from the solvent. This will always lead to odors in the solvent whether they are a burnt nut smell of damaged solvent or the foul odors of bacteria. (A sweaty foot smell).
Drying temperatures should be as the drycleaning machine manufacturers recommendations for decent drying times and lint filters and all air chambers must be kept free of lint.
For greater production, a hydrocarbon reclaiming dryer may be added to the cleaning room so a load can be drying while another load is being washed in the dry-to-dry machine. For large production facilities generally washer/extractors and several reclaiming dryers are used.
If you need to convert from a perc machine to a lighter than water solvent you will need to buy a larger hydrocarbon dry-to-dry machine than you had been using for perc. If you had a 40-pound perc machine then you might want to buy a 60-pound hydrocarbon machine in order to have about the same production.