TITLE: A new composition for the manufacture of a solvent-based cleanser
INVENTOR: Elizabeth Larsen
ABSTRACT: This patent application describes a new method for producing more effective/safer cleansing solvents using naturally occurring hydroxylated esters in an aqueous solution comprising water soluble alcohols, wax esters and emulsifiers.
BACKGROUND: Organic (carbon-containing) residues (such as grease, grime, makeup, resins, enamels) can be difficult to remove from surfaces. Solvents must be used to break up these residues so they can be rinsed or wiped away – usually with water. The difficulty comes from the nonpolar nature of these organic residues. Nonpolar molecules do not bond to water molecules, as water molecules are polar. In short, the problem is ‘oil and water don’t mix.’
There are countless degreasers described in the current patent literature. However, because they do not address this adage, they always prove unsatisfactory – often in both their effectiveness and their harsh nature to not only surfaces but also the environment. For example, mechanical action (like scrubbing) can loosen debris, but is damaging. Detergents incorporate surfactants which are both polar and nonpolar, but often are limited in their effectiveness as they typically form micelles. Because this process is not reversible, detergents are used up quickly. Nonpolar solvents can be used, but cannot be rinsed away with (polar) water. Ethoxylated solvents are described which can be effective as they have both polar and nonpolar aspects. However, these are expensive to make and result in hazardous byproducts. There is an obvious need for a new composition comprising a nontoxic yet effective cleanser for these organic residues.
SUMMARY OF THE INVENTION
This new composition addresses the problem by dissolving and holding these undesirable residues in a nontoxic suspension that itself is soluble in water. It is well-known that, ‘Like dissolves like.’ Chemically speaking, this phrase means nonpolar substances (such as grease and grime) are attracted to nonpolar substances, but not polar ones. Conversely, polar substances are attracted to only polar substances. This solvent overcomes this difficulty by including a component in which both water and nonpolar substances are soluble. Furthermore, this composition creates an environment that encourages the chemical reactions that dissolve these undesirable residues.
BRIEF DESCRIPTION OF THE DRAWINGS
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Figure 1. Figure 1 shows the esterification/hydrolysis reaction. The main reaction by which this solvent works.
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Figure 2. Figure 2 shows the fatty acids comprising castor oil. The relevant attributes are the hydroxyl groups, making castor oil soluble in alcohols.
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Figure 3. Figure 3 shows the miscibility of alcohols in water due to hydrogen bonding.
DETAILED DESCRIPTION AND BEST MODE OF IMPLEMENTATION
The mechanism for cleaning requires dissolving undesirable residues and somehow holding them in suspension to be removed – often with water. However, the adage ‘oil and water don’t mix’ generally applies – making this difficult to accomplish. This new composition for cleansers results in an emulsion that comprises a nonpolar component in the oil phase that actually dissolves in the aqueous phase. Nonpolar residues are better held in this suspension and therefore can be more completely rinsed away. Furthermore, this invention results in a more complete dissolving of these residues by creating a weakly acidic environment which encourages the esterification/hydrolysis of the organic components. This is the reaction that breaks up/dissolves these undesirable residues. The goals of more completely breaking up residues and more effectively holding them in suspension are accomplished in the following three ways. First, this new solvent incorporates an alcohol soluble nonpolar component in the oil phase (castor oil) while including short-carbon-chain alcohol(s) in the aqueous phase. Secondly, it contains naturally occurring hydroxylated esters such as waxes and other triglycerides in the oil phase. And thirdly, emulsifiers are used to create an environment which encourages the reactions that break up these undesirable residues.
Beginning with the aqueous phase, short chain alcohols, specifically ethanol and/or one of the propanols are included as they are miscible in water. The organic phase contains hydroxylated esters specifically castor oil and one or more waxes and other triglycerides (coconut oil, for example). The hydroxyl groups of these esters make them soluble in these short chain alcohols which are themselves soluble in water. In short, oil and water can mix – resulting in a suspension more effectively rinsed away. Glycerol is also included in the aqueous phase. Glycerol is miscible in both the oil and aqueous phases and forms the backbone of triglycerides like castor oil and some of the components of these undesirable residues. The increased concentration of these glycerols helps drive the reactions that break up residues.
Secondly, as mentioned, the reaction which does the cleaning is the hydrolysis of the esters making up the residues. The hydrolysis/esterification reaction is highly reversible. Including esters in the solvent drives the equation resulting in more fatty acids and fatty alcohols to attack and dissolve these undesirable residues. Additionally, because hydroxylated esters, like some components of castor oil and waxes, are used, the dissolved residues are held in suspension in the nonpolar/alcohol containing aqueous phase more effectively than with current cleansers. Other triglycerides of multiple chain length fatty acids are also incorporated increasing the types of residues that can be effectively cleaned. Moreover, these reactions are catalyzed in the acidic environment which naturally results from the dissolution of these esters.
Finally, a polymer matrix is formed, using emulsifiers specific to the application. These large molecules form a lattice of reactive groups that provide physical space for reactions to occur as well as sites that encourage activity. At the same time, the reaction which cross-links these polymers results in a slightly more acidic environment, further encouraging the hydrolysis/esterification reaction.
The composition of the solvent can vary depending on the application. By changing the alcohols and triglycerides used, solvents can be produced for any application from degreasers for industrial equipment to dish liquid to facial cleansers/shampoos. Likewise, changing waxes or emulsifiers will alter the performance of the solvent. By adding pumice, a very effective hand cleanser has been made. Wetting a cotton wipe with the solvent makes an effective makeup remover. Potential embodiments are numerous.
CLAIMS
What is claimed is:
The only claim is that the solvent comprises castor oil in short chain alcohols, glycerol and water combined with wax esters and emulsifiers. Specifics will vary with application.