Dimer amidopropyl dimethyl quaternary compounds

The present invention relates to a novel class of compounds having specific quaternized amine based upon a dimer acid amido amine quaternary compound. Dimer acid is a C-36 diacid having a cyclic structure and two amine groups that allow for the synthesis of a high molecular weight cationic compound which is extremely substantitive to human skin and are well tolerated by human tissue making them suitable for use preparation of barrier products for personal care applications.

It is very desirable to provide a material from aqueous solution that will condition the hair and still be compatible with anionic surfactants. This allows for the preparation of clear two in one shampoo systems, clear 2 in one shower gels, and clear two in one bath products. By two in one products in meant, a product that contains both anionic surfactant, most commonly sulfates and ether sulfates and a cationic conditioning agent. The anionic surfactant is the detergent, which cleans the hair or skin, and the cationic product is for conditioning providing softness, slip and feels to the skin. The problem with such product has always been the incompatibility of the anionic and cationic surfactants with each other. When many of these products are present in the same solution an insoluble salt forms making a cosmetically unacceptable white gunk that does not stay in solution.

As will become clear, by making a very large molecule the present invention results in a we call a soft quaternary compound. By soft quaternary compound is meant one that not withstanding its cationic charge is of a structure so that when placed in water along with the anionic surfactant, a clear stable solution is obtained. Surprisingly, because of the high molecular weight of the quaternary compound, the deposition on the hair and skin is increased. While not wanting to be held to only one mechanism, we believe there rather than a precipitate observed with so-called hard quarts, compounds of the present invention form a self-assembling complex between the anionic and cationic surfactant. This complex, while water-soluble is large enough to disrupt hydrogen bonding between water molecules, and as such energetically, the complex will be deposited on the skin or hair leaving the remaining solution at the lowers free energy level.

The self-assembling aspect of the present invention, which we believe is the result of orientation of the salt of the cationic compounds of the present invention and the anionic surfactants present in solution, can be demonstrated by the fact that upon initial mixing of the components, a hazy or cloudy dispersion occurs. With suitable mixing, this hazy dispersion becomes a solution and the viscosity increases.

The compounds of the present invention can be formulated into body washes and other skin products and hair care products to provide a “delivery system” for conditioning the hair or skin. The high molecular weight of the quart and the fact that the point. charges are far apart in the molecule results in through and efficient deposition on the hair or skin. This provides uniformity of conditioning agent over the entire hair of skin surface. This is particularly important for applications on hair for people with long hair. In general the long hair has at it's tip areas that are more damaged, dry and in need of conditioning. The hair closest to the scalp is newer, less damaged, and less in need of conditioning. This dichotomy of hair condition is more effectively treated by the complexes formed by the current invention than by other quarts. In addition, the di-nature of the compounds provides for outstanding substantivity of the molecule allow for very mild natural like materials that can be used in products where low irritation is important.

U.S. Pat. No. 6,331,293 issued Dec. 18, 2001 to Smith et al describes phosphobetaines that are derived from dimer acid. Unlike the compounds of the present invention, these materials, are anphoteric surfactants and are barriers when applied to the skin. It is stated that the compounds are “extremely substantitive to human skin and are well tolerated by human tissue making them suitable for use preparation of barrier products for personal care applications”. Unlike these materials, the compounds of the present invention are not amphoterics, but are quarts, are not barriers but are conditioning agents that do not build up on the hair or skin.

Objective of the Invention

It is the objective of the invention to provide a novel dimer acid based arnido quatemary compounds and a process of its use which comprises contacting the skin with an effective conditioning concentration of the novel quaternary compounds when applied in aqueous solution containing anionic surfactants. These anionic surfactants are preferably fatty sulfates and fatty ether sulfates having between 1 and 4 moles of ethylene oxide present.

In accordance with the present invention, we have now been discovered novel quaternary compound, which conforms to one of the following structures:

The first structure is:

wherein;

R 1 is selected from the group consisting of —CH 3 , —CH 2 -CH(OH)CH 2 OH and

The second closely related structure is:

wherein;

R 1 is selected from the group consisting of —CH 3 , —CH 2 -CH(OH)CH 2 OH and

The difference between the two is the second has no double bond in the cyclic structure, while the first has a double bond. The double bond is removed by hydrogenation of the acid prior to making the quaternary compound. This vari ation has lighter color and better oxidative stability, making it prized for cosmetic applications where a water white product is desired. Consumers consider water white products as cleaner and more appealing over yellow products.

The present invention is also directed to a process for very efficiently conditioning the skin and hair from aqueous solution containing anionic surfactant. The complex that forms is very efficient in providing conditioning and can be used at concentrations as low as 0.5% by weight in a shampoo formulation. This is very important in products where low irritation is important like baby shampoo and bubble bath products.

Preferred Embodiments

In a preferred embodiment R 1 is —CH 3 .

In a preferred embodiment, R 1 is —CH 2 —CH(OH)CH 2 OH.

In a preferred embodiment R 1 is

The present invention is directed to novel cationic compounds, which conform to one of the following structure:

The first structure is:

wherein;

R 1 is selected from the group consisting of —CH 3 , —CH 2 —CH(OH)CH 2 OH and

The second closely related structure is:

wherein;

R 1 is selected from the group consisting of —CH 3 , —CH 2 —CH(OH)CH 2 OH and

The compounds of the present invention are prepared by reacting first reacting dimer acid with dimethylaminopropyl amine (DMAPA) to give a tertiary amine intermediate.

The first structure is:

wherein;

R 1 is selected from the group consisting of —CH 3 , —CH 2 —CH(OH)CH 2 OH and

The second closely related structure is:

wherein;

R 1 is selected from the group consisting of —CH 3 , —CH 2 —CH(OH)CH 2 OH and

In a subsequent step, the dimer DMAPA product is reacted with methyl chloride or chloroglycerin to give the compounds of the present invention.

The compounds of the present invention are made reaction of the methyl chloride or chloro glycerin under aqueous conditions. The product of the invention is thereby attained.

The compatibility of this novel quatemary compounds of the invention with human tissue, i.e., dermal and eye tissue has also been tested. In these tests, 48-hour human patch dermal evaluations (5% in water), in vitro ocular evaluations (3% in water) and repeated insult patch tests (3% in water) determined that the compounds are substantially non-irritating to humans, they are safe and suitable for use in eye area products and are not a skin sensitizer to humans.

Dimer Acid and Hydrogenated Diner Acid

Dimer acid and hydrogenated dimer acid are items of commerce commercially available from several suppliers, one of which is Cognis Corporation, formerly the Emery Division of Henkel.

Dimer acid conforms to the following structure;

Hydrogenated dimer acid conforms to the following structure;

Dimethylaminopropyl Amine is an item of commerce available from a variety of sources including Dow Chemical.

H 2 N—CH 2 ) 3 —N—(CH 3 ) 2

Chloroglycerin

Chloroglycerin is a item of commerce available from a variety of sources including Dixie Chemical and Phoenix Chemical of Somerville, N.J. It conforms to the following structure:

Cl—CH 2 —CH(OH)CH 2 —OH

Methyl Chloride

Methyl chloride is an item of commerce and is available from a variety of sources. It conforms to the following structure:

CH 3 —Cl

Benzyl Chloride

Benzyl Chloride is an item of commerce and conforms to the following structure: