It works by slowing and preventing spoilage in products such as shampoos and hair conditioners, and in skin care products like moisturizers and makeup foundations. DMDM hydantoin is also an antimicrobial agent used in cosmetics and personal care products.
As an antimicrobial, it can help prevent the growth of fungi, yeast and harmful bacteria that can make people sick or give them rashes, for example. A recent safety assessment published in the International Journal of Toxicology reaffirmed that formaldehyde can be used safely in cosmetics if established safety limits are not exceeded. The Cosmetic Ingredient Review CIR , an independent expert scientific panel established by the Personal Care Products Council, also has evaluated the scientific data and concluded that DMDM hydantoin is safe as a cosmetic ingredient at current levels of use — 0.
The Cosmetics Directive of the European Union also has approved DMDM hydantoin as a preservative in cosmetics and personal care products at a maximum concentration of 0. Formaldehyde donors, also known as formaldehyde releasers, are ingredients used in small amounts in personal care products and cosmetics to help prevent mold and bacteria from growing and spoiling products.
It is yet another object of this invention to produce methylolated hydantoins in relatively pure form that are not readily prepared by prior art techniques. These and other objects of our invention will be apparent from the discussion which follows. A hydantoin, a source of formaldehyde, such as paraformaldehyde, and an alkaline catalyst are mixed and reacted at elevated temperatures. This reaction is conducted in the effective absence of water other than that associated, as a hydrate, with the source of formaldehyde.
If a reaction medium is used, it is a melt of the methylolated hydantoin product at reaction temperature. Thus, no separation step, e. Because the product is a pure, dry solid, it can be transported more economically than the aqueous solutions previously known in the art. The product can be dissolved easily into a solution at ambient temperature, if desired. Because the product contains essentially no water, it may be incorporated into non-aqueous systems, an obstacle not easily overcome with products made in the conventional water-based processes.
A preferred hydantoin reactant for this method is 5,5-dimethylhydantoin, which produces 1,3-dimethylol-5,5-dimethylhydantoin, DMDMH. This product can be used as a cosmetic preservative, functioning as a formaldehyde-donating antimicrobial agent, as well as for a variety of other purposes. Other objects, features, and characteristics of the invention will become apparent upon consideration of the following description and claims.
The process of our invention comprises reacting a hydantoin and a source of formaldehyde, preferably paraformaldehyde, in the presence of an alkaline catalyst and in the effective absence of water the water content of the reactant mixture, including any water associated with the formaldehyde, typically is no more than about 1 weight percent , at conditions sufficient to induce reaction, resulting in the production of a methylolated hydantoin.
The methylolated product, either added or formed by initial reaction and which is a melt at reaction temperature, becomes the medium in which total reaction readily takes place. Paraformaldehyde, a non-aqueous formaldehyde polymer with the chemical formula HO- CH 2 O n -H n is about , is well known in the art. Typical alkaline catalysts are alkali metal and alkaline earth metal salts such as sodium carbonate, sodium bicarbonate, calcium bicarbonate and sodium hydroxide, which are known and readily available.
Other suitable alkaline catalysts are also within the scope of the invention. The hydantoin reactants, many of which are well known in the art, typically include 5,5-dimethylhydantoin, 1-monomethylol-5,5-dimethylhydantoin, and 5-ethylmethylhydantoin, which can be reacted separately or in combination. Corresponding products include 1,3-dimethylol-5,5-dimethylhydantoin, 1- or 3-methylol-5,5-dimethylhydantoin, 1,3-dimethylolethylmethylhydantoin and 1- or 3-methylolethylmethylhydantoin.
Additional hydantoin reactants that may be used include hydantoins which will react with non-aqueous formaldehyde in the presence of an alkaline catalyst and in the effective absence of water or any other reaction medium except for the product.
If the reaction is conducted at a pressure other than atmospheric pressure, suitable and preferable temperature ranges will depend upon the rates of the decomposition of paraformaldehyde, the reaction of paraformaldehyde with a hydantoin, and the vaporization of paraformaldehyde at that pressure. The medium in these cases would be the melt form of the reactant.
The spirit of the invention is the same, i. The resulting methylolated hydantion product contains less than 0. For example, 5-methylhexylhydantoin, M. Also, 5,5-diethylhydantoin M. Other hydantoins, such as 5,5-pentamethylene hydantoin I , alkoxyalkyl derivative II , or 5-alkyl derivatives III , STR1 all represent potential candidates for processing by this invention.
Other N-substituted hydantoins, e. All of the above compounds, as well as others not specifically disclosed, are within the spirit of the invention. Accordingly, products which are formed using these various reactants are within the scope of this invention. Condensation products of hydantoin and paraformaldehyde in the present invention generally are methylolated hydantoins which contain 1, or, more likely, 2 moles of formaldehyde.
The products of this invention may also include methylolated hydantoins formed by the addition of more than 2 moles of formaldehyde per mole of hydantoin, such as 1-methylolmethyloloxymethylene-5,5-dimethylhydantoin, and 1,3-dimethyloloxymethylene-5,5-dimethylhydantoin.
In a typical process of this invention, hydantoin and commercially available paraformaldehyde are combined with a small amount of catalyst and the mixture is melted. Alternatively, it is premixed as a solid with the reactants before heating. The mixture is allowed to react completely and is then cooled to room temperature, causing crystallization of the hydantoin-formaldehyde adduct. We have found that the reactant ratio of 2 moles of formaldehyde per mole of dimethylhydantoin results in almost complete combining of the paraformaldehyde.
The quantity of catalyst needed for this reaction is small, and need comprise only about 0. However, the process is not limited to these conditions, as explained above.
The reactants can be heated in any suitable manner, for example, in an oil bath. The reactants may be mixed before heating, such as on a ball mill.
At the conclusion of the reaction, purifying means, such as a vacuum, may be applied to the reaction mixture, preferably at reaction temperature, to essentially eliminate any moisture or residual formaldehyde odor that might exist prior to application of the purifying means. It is noted that this step is not essential to the production of commercially useful methylolated hydantoins using the method of this invention.
The following examples are offered in order to more fully illustrate the invention, but are not to be construed as limiting the scope thereof. After about 15 minutes the mixture was a melt, and after a total of 45 minutes the reaction was complete. The molten product was discharged to trays for hours for crystallization at room temperature, and was then analyzed using conventional techniques.
Morbi, Dist. Kolkata 36, Strand Road, 4th floor, R. Kolkata, West Bengal. Kandivali, Mumbai Office No. Road, Kandivali, Mumbai - , Dist. New Delhi House No. Have a requirement? Get Best Price. View by: Product Supplier. Location Near Me. Kosmetika Enterprises. Shreenath Traders. Orchem Products. KIP Chemicals. Dmdm Hydantoin. Maya Chemtech India Private Limited. Bodar Industries. Shree Ganesh Chemicals. Ask Price. Lachemi Chemorgs Private Limited. Dmdm Hydentoin.
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