Cleaning compositions for solid surfaces – auxiliary compositions – Cleaning compositions or processes of preparing – For cleaning a specific substrate or removing a specific...
Patent
1996-02-22
1998-06-23
Howard, Jacqueline V.
Cleaning compositions for solid surfaces, auxiliary compositions
Cleaning compositions or processes of preparing
For cleaning a specific substrate or removing a specific...
510245, 510272, 510365, C11D 152, C11D 108, C11D 174
Patent
active
057705500
DESCRIPTION:
BRIEF SUMMARY
This invention relates to surfactant compositions and in particular to aqueous surfactant compositions with a high electrolyte loading, in particular of alkali.
In the industrial cleaning of hard surfaces, such as those of metals, ceramics, glass and plastics, the cleaning processes typically involve spraying or dipping of the substrate into a cleaning fluid. In contrast to domestic cleaning, the use of mechanical surface rubbing is not usually used because it is difficult to use uniformly on other than very regularly shaped objects and is expensive. Energy may be supplied to the system to assist cleaning by agitation or the use of ultrasound. To compensate for the non-use of mechanical surface rubbing, the cleaning materials used are often much more aggressive than are used in domestic situations where contact with the user's skin is to be expected (or at least planned for even if inadvertent). Thus, aqueous industrial cleaning fluids can have high concentrations of electrolyte materials particularly acid materials or and especially alkali materials. When the electrolyte is an alkali it can be a moderately strong alkali such as soda ash (sodium carbonate) or it can be a strong alkali such as caustic soda (sodium hydroxide). A typical need for such cleaners is the removal of fatty, waxy or oily soils adherent to the substrate. The action of such materials may include chemical modification of the soiling material e.g. by alkali hydrolysis of fats to acids and alcohols. However, simple aqueous solutions of acids or alkalis are not good wetters of such hydrophobic materials and are thus relatively ineffective as cleaners. The inclusion of surfactant, usually synthetic surfactant, materials can improve the wetting power of the cleaning fluid and keep detached contaminants suspended away from the substrate being cleaned.
This invention is directed to this type of cleaning of hard surfaces using aqueous surfactant compositions with a high electrolyte loading, particularly where the electrolyte is or includes alkali.
Aqueous surfactant compositions with a high electrolyte loading of this general type are known as industrial cleaners and particularly as so-called `hard surface cleaners`. They are used principally in the metal working industries, including the automotive industry and its support industries, in the cleaning of hard surfaces and the passivation, including metal degreasing, e.g. in spray cleaning plant. They are suitable for intermediate and final cleaning, including that of machined and otherwise shaped parts in engineering and assembly plants. In general, in such applications in the metal working industries such aqueous surfactant compositions are used to remove the majority of all surface contaminants arising from the working of the materials and to remove metal particles from machined or otherwise shaped parts arising from the working of the materials.
Industrial cleaning compositions of this type may be used in the metal working industries in spray cleaning plant. They are however also used in dipping and/or ultrasonic processes which are standard in these industries, including the automotive industry and its support industries, for the cleaning of hard surfaces and passivation, including metal degreasing.
Such known compositions for the cleaning of hard surfaces and passivation, including metal degreasing, are chiefly used on machined and otherwise shaped parts in engineering and assembly plants at ambient to moderately elevated temperatures, e.g. in the range of 15.degree. to 80.degree. C.
They are typically used at pH values of for example 4 to 13.5, and particularly 9 to 13.5 (by the inclusion of strongly alkaline hydroxides or carbonates, for example of sodium or potassium in the compositions), and in particular at less moderately elevated temperatures, e.g. nearer to 40.degree. to 80.degree. C., in use.
Known compositions of this type for the cleaning of hard surfaces and passivation, including metal degreasing, include those of such surfactants as alkyl phenol ethoxylates and fatty alcohol
REFERENCES:
patent: 5196136 (1993-03-01), Dishart et al.
patent: 5543073 (1996-08-01), Adamy et al.
Howard Jacqueline V.
Imperial Chemical Industries plc
LandOfFree
Surfactants does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Surfactants, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Surfactants will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1394662