Patent Application
20120135905
The present invention relates to an aerosol electrical contact cleaning and lubricating compound. More specifically, but without limitation, the present invention relates to a plastic-safe aerosol cleaning and lubricating compound for use on electrical contacts, connectors, switches, and the like.
Electrical contact cleaning and lubricating compounds are used during the manufacture and maintenance of electronic and avionics equipment. They are used to clean and lubricate the components prior to final assembly. The solvents in these electrical contact cleaning and lubricating compounds remove greases, oils, corrosion preventive compounds, oxidation products, and the like. The lubricant reduces friction and wear of electrical contacts.
Many cleaning and lubricating compounds are in aerosol form. These aerosol cleaning and lubricating compounds typically contain solvents, a lubricant, and a propellant. CFC-113 (Freon® TF, trichlorotrifluoroethane) and HCFC-141b (1,1-dichloro-1-fluoroethane) were found to be effective solvents for theses type of cleaning and lubricating compounds. However, both are Ozone Depleting Substances and have been phased out of use. Hydrofluoroethers (HFEs) and perfluorocarbons (PFCs) were developed as substitutes. However, HFEs and PFCs are not effective in formulating electrical contact cleaning and lubricating compounds using a silicon based oil lubricant, which is the most commonly used lubricant in electrical contact cleaning and lubricating compounds. There are also electrical contact cleaning and lubricating compounds that are formulated with partially fluorinated hydrocarbon based solvents, but they are not safe to use on acrylics.
Plastics are often used as substrates or supports in printed circuit boards, especially in electronic and avionics equipment. Typically, electronic circuitry is printed on a polycarbonate substrate. A conformal coating is then applied to the electronic circuitry for protection against moisture, dust, chemicals, and temperature extremes. A popular conformal coating material is acrylic. The currently used aerosol contact cleaning and lubricating compounds typically attack acrylic and plastic materials.
An electrical contact cleaning and lubricating compound needs good plastic compatibility, high cleaning efficiency, low flammability, and a high evaporation rate. Plastic compatibility is especially important in the aerospace industry because incompatible cleaning and lubricating compounds damage plastic avionic and structural parts. Such damage can compromise aircraft performance.
For the foregoing reasons, there exists a need for an electrical contact cleaning and lubricating compound having good cleaning and lubricating ability that does not damage avionic and structural parts.
The present invention is directed to an aerosol electrical contact cleaning and lubricating compound that meets the needs enumerated above and below.
The present invention is directed to an aerosol electrical contact cleaning and lubricating compound formulation that includes a first solvent that is a mixture of methyl nanofluoroisobutyl ether and methyl nanofluorobutyl ether, a second solvent that is a dichloroethylene, a third solvent that is an alkyl cyclohexane, a lubricant that is perfluropolyether oil, and a propellant that is a hydrofluorocarbon liquefied gas.
It is a feature of the present invention to provide an aerosol electrical contact cleaning and lubricating compound that has good cleaning and lubricating ability and does not damage avionic and structural parts.
It is a feature of the present invention to provide an aerosol electrical contact cleaning and lubricating compound that does not utilize any banned or Ozone Depleting Substances.
It is a feature of the present invention to provide a formulation for an aerosol electrical contact cleaning and lubricating compound that has high solubility toward lubricants such as silicon based oil.
It is a feature of the present invention to provide an aerosol electrical contact cleaning and lubricating compound that does not damage plastics or acrylics.
It is a feature of the present invention to provide an aerosol electrical contact cleaning and lubricating compound that is non-flammable, effective in the removal of the soils commonly encountered in the aerospace industry, and fast drying without causing icing.
The preferred embodiments of the present invention are illustrated by way of example below. The aerosol electrical contact cleaning and lubricating compound formulation includes a first solvent, a second solvent, a third solvent, a lubricant, and a propellant. The first solvent is a mixture of methyl nanofluoroisobutyl ether and methyl nanofluorobutyl ether. The second solvent is a dichloroethylene, while the third solvent is an alkyl cyclohexane. The lubricant is perfluropolyether oil, and the propellant is a hydrofluorocarbon liquefied gas.
In the description of the present invention, the invention will be discussed in a electronics and avionics environment. However, this invention may be utilized on any type of surface that requires cleaning and lubrication.
The preferred second solvent is trans 1,2-dichloroethylene, while the preferred third solvent is methyl cyclohexane. The preferred lubricant is perfluropolyether oil, and the preferred propellant is 1,1,1,2-tetrafluoroethane. However, any lubricant or propellant that is practicable can be utilized.
In the preferred embodiment of the formulation, the first solvent has a concentration of about 43% by weight of the formulation, the second solvent has a concentration of about 6% by weight of the formulation, the third solvent has a concentration of about 12% by weight of the formulation, the lubricant has a concentration of about 1% by weight of the formulation, and the propellant has a concentration of about 38% by weight of the formulation.
When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a,” “an,” “the,” and “said” are intended to mean there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
Although the present invention has been described in considerable detail with reference to certain preferred embodiments thereof, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred embodiment(s) contained herein.
The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without payment of any royalties thereon or therefor.
