Paint removers, methylene chloride

See also Finish removers Paint solvents, 18 59-60 Paint stripping, methylene chloride in, 16 378... 

The rate of stripping or the stripabiUty on cataly2ed urethane and epoxy resin finishes can be increased by adding formic acid, acetic acid, and phenol. Sodium hydroxide, potassium hydroxide, and trisodium phosphate [10101-89-0] may be added to the formula to increase the stripabiUty on enamel and latex paints. Other activators include oleic acid [112-80-17, trichloroacetic acid [76-85-9], ammonia, triethanolamine [102-71-6], and monoethyl amine. Methylene chloride-type removers are unique in their abiUty to accept cosolvents and activators that allow the solution to be neutral, alkaline, or acidic. This abihty gready expands the number of coatings that can be removed with methylene chloride removers. 

Methylene Chloride Consumption By Paint and Coating EemovalGroups, Paint Remover Manufacturer s Association, 1992. 

Methylene chloride has a wide variety of markets. One major use is a paint remover. It is also used as a degreasing solvent, a blowing agent for polyurethane foams, and a solvent for cellulose acetate. 

In addition to tobacco smokers, individuals who have had previous exposure to materials containing methylene chloride, such as degreasers, solvents, paint removers, and furniture strippers, are at greater risk because of an existing body burden of carbon monoxide. Approximately one-fourth to one-third of inhaled methylene chloride vapor is metabolized in the liver to carbon monoxide. In addition, methylene chloride is readily stored in body tissue. This stored material is released over time and results in elevated levels of carbon monoxide for extended periods, in some cases more than twice as long as compared with direct carbon monoxide inhalation. 

Organic solvents inhaled by abusers include gasoline, glue, aerosols, amyl nitrite, butyl nitrite, typewriter correction fluid, lighter fluid, cleaning fluids, paint products, nail polish remover, waxes, and varnishes. Chemicals in these products include nitrous oxide, toluene, benzene, methanol, methylene chloride, acetone, methyl ethyl ketone, methyl butyl ketone, trichloroethylene, and trichloroethane. 

A profile of methylene chloride is presented including US production capacities, demand, growth rate, price, uses, strength, weakness and outlook. Paint stripping and removal accounts for 30% of MeC by end-use application, adhesives 20%, metal cleaning 10%, aerosols 10%, pharmaceuticals 10%, chemical processing 10% and flexible PU foams 5%. Because of occupational concerns, users of MeC are under pressure to limit use, restrict... 

Environmental Impact. Methylene chloride is nonphotochemically reactive and is not listed as an ozone (qv) depleler. Methylene chloride removers can easily be recovered from paint chips and other residue sedimentation, tlius allowing recovery of remover and its continued use. Tins greatly increases the useful life of the remover and, when mixed with fresh remover, eluninates the need for disposing of the used remover. This process requires no special recovery equipment. The high volatility of methylene chloride allows the waste residue from the stripping process to be easily dried, The resulting waste is normally considered hazardous because of the amounts of heavy metals from old finishes. 

Solvents Polish remover contains acetone paint remover, paint thinner, and correction fluids contain toluene (an aromatic hydrocarbon), methylene chloride, and methanol fuel gas contains butane lighter fluid contains butane and isopropane fire extinguishers contain bromochlorodifluo-romethane. 

The artist, with the help of a sound knowledge of chemistry, can substitute less-toxic materials for highly toxic substances. For example, methyl alcohol, toluene, or methylene chloride can be substituted for benzene, which is used as a paint and varnish remover, and boric acid can be substituted for phenol, which is used as a preservative. The chemist needs the artist to shed new light and for a new point of view so that the chemist can develop appropriate and better art materials. 

The main uses of methylene chloride are in paint remover, aerosols, chemical processing, urethane foam blowing agents, metal degreasing, and electronics. 

Methylene chloride (CH2C12) and chloroform (CHC13) are also good solvents for cleaning and degreasing work. Methylene chloride was once used to dissolve the caffeine from coffee beans to produce decaffeinated coffee. Concerns about the safety of coffee with residual traces of methylene chloride prompted coffee producers to use liquid carbon dioxide instead. Chloroform is more toxic and carcinogenic than methylene chloride it has been replaced by methylene chloride and other solvents in most industrial degreasers and paint removers. 

Methylene chloride is used primarily as a solvent for degreasing and paint removal, and it is also used in aerosols and foam-blowing agents. Since 1985, new environmental regulation has had a major impact on this chemical. The consumption of methylene chloride has been reduced by 60 percent due to recycling and product substitutions. 

Methylene chloride, a volatile chlorinated hydrocarbon, is used as a paint remover, metal degreaser, and aerosol propellant. The odor threshold for methylene chloride in the air is 100 ppm. According to Shelton (1989), it has been shown to induce tumors in mice. 

Cj Derivatives. The clilorinated methanes, chloroform, methylene chloride, and carbon tetrachloride, consumed approximately 0.8 million tons of clilorine in 1987 and aggregate growth rates from this segment of the industry are expected to remain relatively flat through 1992. Because of its contribution to ozone depletion, carbon tetrachloride use in chlorofluorocarbon manufacture will be phased out in compliance with the recent Montreal Accord. In addition, environmental pressures are expected to continue to impact the use of methylene chloride in aerosol and paint remover applications. Some of the decreases in C1 derivatives should be offset by positive growth for chloroform in HCFC-22 manufacture, which has not been implicated in ozone depletion (see CHLOROCARBONS AND CHLOROHYDROCARBONS, METHYL CHLORIDE METHYLENE CHLORIDE CHLOROFORM CARBON TETRACHLORIDE). 

Trichloroethylene and 1,1,1-trichloroethane are used in correction fluids, dry-cleaning products, degreasing sprays, and solvents and spot removers. Bromochlorodifluoro-methane is a compound found in halon fire extinguishers that is abused. Freon is used for refrigeration and air conditioning systems. Anesthetics include halothane, chloroform, and the local anesthetic ethyl chloride. Methylene chloride is a component of rubber cement, paint strippers, and degreasing agents, and fluorocarbons are present in many types of aerosol sprays. 

Some VOCs can be malodorous pollutants, sensory irritants, or hazardous air pollutants. Hazardous VOC air pollutants include acetaldehyde, benzene, carbon tetrachloride, chloroform, ethylbenzene, formaldehyde, hexane, methylene chloride, naphthalene, paradichlorobenzene, pesticides (biocides), styrene, tetrachloroethylene, toluene, trichloroethylene, and xylenes. They are found in essentially all indoor locations, released by off gassing from numerous sources, such as construction and decorating materials, consumer products, paints, paint removers, furnishings, carpets, and from combustion of wood, kerosene, and tobacco. While more than 500 VOCs have... 

Proposition 65 s warning requirement has provided an incentive for manufacturers to remove listed chemicals from their products. For example, trichloroethylene, which causes cancer, is no longer used in most correction fluids reformulated paint strippers do not contain the carcinogen methylene chloride and toluene, which causes birth defects or other reproductive harm, has been removed from many nail care products. In addition, a Proposition 65 enforcement action prompted manufacturers to decrease the lead content in ceramic tableware and wineries to eliminate the use of lead-containing foil caps on wine bottles. 

Methyl chloride, methylene dichloride. Colourless liquid, bp 40-41°C. Industrial solvent and paint remover. Fumigant. Rapidly metabolized to carbon monoxide produces carboxy-Hb. Irritant to eyes and skin blistering on prolonged contact. Anaesthetic effects on CNS coma, death. 

Methylene chloride (CH2CI2) is used as an aerosol propellant, paint remover, and a blowing agent in polymers. It also is used as a solvent in the metals and in the electronics industry. Methyl chloride will react with benzene to form dimethyldibenzyl methane, an ingredient in the perfume industry because of its orange color [159]. 

Methylene chloride is a common ingredient of paint strippers. On a house, an alternative is to heat with a heat gun, then scrape off the paint with a putty knife. Other solvents are needed for stripping finishes from furniture. Epidemiological work suggests that methylene chloride can cause cancer of the liver, bile duct, and brain.214 It is possible that a professional furniture refinisher could be hired to remove the finish by ultrasonic cleaning or bombardment with particles. Further work is needed. 

Chloroform is a volatile, sweet-tasting liqnid that was nsed for many years as an anesthetic. However, because of its toxicity (it can severely damage the liver, kidneys, and heart) it has been replaced by other componnds. Carbon tetrachloride, also a toxic substance, serves as a cleaning liquid, for it removes grease stains from clothing. Methylene chloride is nsed as a solvent to decaffeinate coffee and as a paint remover. 

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