Hughes Aircraft Company

Raytheon Company

Hughes Electronics Corporation

Other

Sidney C Chao

Edna M Purer

Nelson W Sorbo

Carl W Townsend

Thomas B Stanford

Angela Y Wilkerson

Edward J Palen

Robert W Beach

Thomas B Stanford,Jr

Chris Lee

Fabrics are cleaned by treating at least a portion of the piece of fabric with a particulating chemical, and agitated by a gas jet of a particle-dislodging gas to dislodge the particulated soil. The particulating chemical loosens embedded non-particulate soil and converts it to a particulate form, which is then separated from the fabric by the particle-dislodging gas.

Gas jet removal of particulated soil from fabric

A soiled piece of fabric is cleaned by mechanical agitation while the fabric is simultaneously subjected to acoustic energy in a gaseous environment wherein the piece of fabric is not immersed in a liquid cleaning medium. Mechanical agitation may be by gas jet action and/or by tumbling. The acoustic energy vibrates the fibers of the fabric to enhance the cleaning action. The piece of fabric may be chemically treated to mobilize the soil.

Acoustic-energy-assisted removal of soil from fabric in a gaseous environment

A cleaning system and method utilizing sonic whistle and other agitation methods to enhance the soil removal and mass transport capacity of the liquid carbon dioxide at low process temperatures. Agitation devices disposed in or couple to a cleaning chamber, and cause the liquid carbon dioxide to ultrasonically emulsify and disperse non-miscible liquids or insoluble solids, such as remove low solubility oils and greases. Cleaning is accomplished at temperatures between &minus;68&deg; F. and 32&deg; F., and the temperature of the liquid carbon dioxide is typically below 32&deg; F.

Liquid carbon dioxide cleaning using agitation enhancements at low temperature

A piece of soiled fabric is cleaned by contacting it with a jet of an ionized soil-dislodging gas to dislodge the soil therefrom. The ionized gas and the use of an oppositely charged electrostatic filter aid in preventing redeposition of the soil onto the fabric. The fabric may be agitated while it is contacted with the gas jet. A portion of the piece of fabric may be treated with an electrostatic spotting compound that enhances the effect of the ionized gas and may also enhance the removal of the soil. An apparatus for accomplishing the cleaning includes a container having an interior in which the fabric is received, a gas jet nozzle directed into the interior of the container, a source of a pressurized gas communicating with an inlet of the gas jet nozzle, a gas jet manifold extending from the source to the gas jet nozzle, and a gas ionizer disposed to ionize the pressurized gas passing through the gas jet nozzle.

Removing soil from fabric using an ionized flow of pressurized gas

A process is provided for cleaning, disinfecting, and sterilizing substrates comprising the steps of: (a) placing the contaminated substrate in a cleaning vessel; (b) contacting the contaminated substrate with dense phase carbon dioxide in liquid form; (c) subjecting the substrate and the dense phase carbon dioxide to ultraviolet radiation having a wavelength within the range of about 180 to 300 nm for a duration and intensity sufficient to produce a photochemical reaction capable of destroying the DNA of microorganisms on the substrate; (d) substantially simultaneously subjecting at least the dense phase carbon dioxide to agitation; and (e) removing the dense phase carbon dioxide from the cleaning vessel and thereby transporting the contaminants from the substrate such that the substrate is cleaned and, in the case of contaminated garments, disinfected or, in the case of medical and dental instrumentation, sterilized. Substantially simultaneously with the UV exposure and agitation, the substrates are also subjected to an oxidizing sterilant, such as H.sub.2 O.sub.2.

Process for cleaning, disinfecting, and sterilizing materials using the

Substantial amounts of particulate soils in garments can be removed by agitation in gas-jet in a solvent-free, low-pressure environment. The ability of the present gas-jet agitation system to remove particulate soils from garments and fabrics rivals that of conventional dry-cleaning processes which agitate the garments and fabrics while immersed in solvent. Thus, a dry-cleaning operation may consist of a solvent-immersion step for removing soluble soils and a gas-jet agitation step to remove particulates. Considerable savings in equipment and operating costs may be realized in the practice of the invention, since solvent flow rates need not be boosted to provide necessary agitation for particulate soil removal. The savings achievable by employing gas-jet agitation are even more pronounced in dense phase gas dry cleaning systems, which require pressurized environments to maintain a liquified solvent. Advantageously, the apparatus employed in the practice of the invention has no moving parts and is relatively inexpensive to fabricate and maintain. Further, the gas used as a means of agitation may be any commonly-available inexpensive gas, such as carbon dioxide, nitrogen, or air, so that the process is environmentally-friendly.

Dry-cleaning of garments using gas-jet agitation

A cleaning system and method utilizing sonic whistle agitation to enhance the soil removal and mass transport capacity of the liquid carbon dioxide at low process temperatures. Sonic whistles are within a cleaning chamber, and liquid carbon dioxide is forced out of the sonic whistle jets to ultrasonically emulsify and disperse non-miscible liquids or insoluble solids, such as remove low solubility oils and greases, in the liquid carbon dioxide contained in the cleaning chamber. Cleaning is accomplished at temperatures between -68.degree. F. and 88.degree. F., and the temperature of the liquid carbon dioxide is typically below 32.degree. F.

Liquid carbon dioxide cleaning using jet edge sonic whistles at low

A method of replenishing liquid carbon dioxide solvent in a liquid carbon dioxide dry cleaning system or other dense phase carbon dioxide cleaning system. The method uses dry-ice or solid carbon dioxide, as a replenishing stock, thus reducing transportation, storage and handling costs. The method disposes solid carbon dioxide blocks in a cleaning chamber after a cleaning cycle. Liquid carbon dioxide solvent is boiled and is used to melt the solid carbon dioxide blocks. Liquid carbon dioxide solvent produced by melting the solid carbon dioxide blocks is pumped from the cleaning chamber into a storage tank to replenish the liquid carbon dioxide solvent.

Solvent resupply method for use with a carbon dioxide cleaning system

An improved liquid carbon dioxide dry cleaning system containing an improved dry cleaning fluid. The dry cleaning fluid contains an antistatic agent for dissipating static charge on members or garments generated by friction during cleaning thereof. The concentration of the antistatic agent is typically less than 1 percent. Static charge present on the members or garments that are cleaned is transferred through the dry cleaning fluid to ground. This transfer of charge minimizes static charge buildup on the members or garments and suspended soil redeposition onto the members or garments. An odorizing agent or fragrance, and/or a deodorizing agent may be added to the cleaning fluid.

Liquid carbon dioxide cleaning system employing a static dissipating

A nozzle for generating a supercritical fluid from a cleaning fluid. The nozzle includes a mechanism for directing the supercritical fluid onto a surface of a part to be cleaned. The nozzle comprises a body having (a) an interior portion which includes a mechanism for generating the supercritical fluid by suitable temperature and pressure increase of the cleaning fluid; (b) an inlet portion for introducing the cleaning fluid into the interior portion; (c) an outlet portion for directing the supercritical fluid generated in the interior portion onto the surface of the part to be cleaned; and (d) counteracting mechanism for resisting high pressure that is produced during the generation of the supercritical fluid so as to permit the nozzle to be maintained a suitable distance from the surface of the part to be cleaned so that the supercritical fluid impinges on the surface.

Supercritical fluid cleaning apparatus without pressure vessel

Liquid carbon dioxide, in combination with agitation and, optionally, with process enhancers, such as surfactants, and solvents, such as water, is used to remove contaminants from garments or fabrics. Both apparatus and process are disclosed. Carbon dioxide-cleaned garments are rendered free of odor, require no drying, and the cost per unit solvent (by weight) is a fraction of that of conventional solvents.

Dry-cleaning of garments using liquid carbon dioxide under agitation as

A process for removing undesired sub-micrometer particulates from a chosen substrate (16) comprising the steps of: (a) placing the substrate containing the undesired particulates in a cleaning chamber (12) provided with megasonic energy-producing means (20); (b) introducing a liquefied gas (22), such as liquid carbon dioxide, into the cleaning chamber and contacting the substrate containing the undesired particulates with the liquid carbon dioxide at a temperature below its critical temperature; and (c) exposing the liquid carbon dioxide to the megasonic energy-producing means for a period of time sufficient to remove the undesired particulates from the substrate. The substrate containing the undesired particulates may optionally be contacted with carbon dioxide in the dense phase prior to and/or after the treatment with megasonic energy to aid in removal of the undesired particulates. Further, spent liquid carbon dioxide may be treated to regenerate fresh liquid carbon dioxide which is recycled to the cleaning chamber. Other gases besides carbon dioxide which may be used include nitrous oxide, sulfur hexafluoride, and xenon. Further, gas mixtures and gas mixtures with suitable modifiers may be employed.

Method using megasonic energy in liquefied gases

Sonication is employed in the destruction of organic chemicals, using liquid carbon dioxide as the sonicating medium. The process of the invention for decomposing at least one chemical comprises: (a) providing a sonicating vessel equipped with an array of sonicators; (b) introducing the chemical to be decomposed into the sonicating vessel, together with liquid carbon dioxide; and (c) exposing the chemical in the sonicating vessel to sonication for a period of time sufficient to cause the chemical to decompose to form at least one decomposition product. The sonication process may additionally employ one or more of ultraviolet light, oxidizing modifiers such as water, sodium hypochlorite, ozone, or hydrogen peroxide, and reaction-quenching species such as hydrogen (H.sub.2). Depending on the nature of the decomposition product(s), disposal may range from simple concentration of the product and collection thereof (in the case of liquids or solids), to venting to the atmosphere (in the case of gaseous, inert products), to venting to the atmosphere through an appropriate gas-trap (in the case of gaseous product that are toxic, reactive, or considered to be environmentally-controlled substances).

Chemical decomposition by sonication in liquid carbon dioxide

Precision cleaning of parts is performed with liquefiable gases, such as CO.sub.2, without the use of a complex and costly processor system. Rather, simplified and reliable performance for small scale and 'low end' cleaning applications is accomplished without the use of pumps and condensers. The apparatus for removing undesired material from a chosen substrate comprises: (a) an enclosed cleaning chamber in a walled vessel for containing a liquid derived from a liquefiable gas and the substrate containing the undesired particulates and contaminants, the walled vessel adapted to withstand a maximum pressure of about 1,500 pounds per square inch (105.4 kg/cm.sup.2) at ambient temperature; (b) means for supporting the substrate in the cleaning chamber; (c) ultrasonic energy-producing transducer means attached to the walled vessel within the cleaning chamber; (d) inlet means attached to the walled vessel for introducing the liquefiable gas into the cleaning chamber under a pressure less than about 900 pounds per square inch (63.3 kg/cm.sup.2); (e) temperature control means connected to the cleaning chamber for controlling the temperature within the chamber up to about 50.degree. C.; (f) reservoir means for providing the liquefiable gas to the inlet means; (g) means for changing the liquefiable gas to the liquid; and (h) outlet means in the chamber for removing the liquid from the cleaning chamber. The liquid may then be further treated to remove particulates and organic contaminants and either recycled to the cleaning chamber or vented to the atmosphere. The process is especially applicable for general degreasing and particulate removal processes, when high precision cleaning is not required.

Growing community of inventors

Manhattan Beach, CA, United States of America

Sidney C Chao