Substantivity

The perception of a perfume depends, in the first place, upon the presence of odorant molecules in the air, and upon their nature and concentration. Most perfume starts off life as a liquid comprising a wide variety of molecules and of a known composition. In general, perfumers do not have a corresponding knowledge of the composition of volatiles in the air above such a mixture, except on those occasions where headspace analysis has provided hard analytical data (see Chapter 12). Perfumers therefore have to build up knowledge bases that summarize the olfactory behaviour of hundreds of ingredients under many different circumstances  

Gaining this sort of experience is a lifetime s work for a perfumer, but it is possible to help the process by understanding the factors that govern the physical performance of perfume. One of the challenges for the physical chemist is to be able to predict what happens when a perfume is incorporated into different products in particular, how does the composition of the perfume headspace alter, and what will be the in-use perfume behaviour (for example, how to maximize a perfume s 

It is known that as soon as a perfume is incorporated into a product matrix, pronounced effects occur on some ingredients, those for which the microenvironmental interactions have changed significantly. Physicochemical interaction is a consideration no matter what the base, whereas chemical interactions only become really important in consumer products possessing a reactive challenge for fragrance, for example products with low or high pH (e.g. below 4, above 9), or redox power (e.g. cold wave hair products or laundry bleaches). (Chemical stability issues are elaborated in Chapter 9.) 

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A second international conference was held in 1911 but the intrusion of World War I prevented any substantive revisions of the Geneva rules The Inter national Union of Chemistry was established in 1930 and undertook the necessary revision leading to pub lication in 1930 of what came to be known as the Liege rules... 

A number of products designated GRAS are being scmtini2ed by the FDA because of advertisements and claims made by producers or manufacturers of these products. Statements that indicate that feeding such products improve animal performance may require substantive data to support such claims in the future. 

During the drying and, if required, the heat treatment that foUows, the fluorescent whitener is fixed on the substrate. FWAs and dyes used in padding procedures must have low substantivity during the padding operation. This is an important prerequisite for level whitening with no tailing. 

Once the patent appHcation is complete and the inventor has made a formal declaration of inventorship, the appHcation is filed with the U.S. PTO. In the U.S. PTO, the appHcation is the subject of a thorough, formal, and substantive examination by a patent examiner. Once the patent examiner is convinced that the patent appHcation satisfies the statutory requirements provided for under the laws of the United States, the patent appHcation will be allowed to issue as a patent. Issuance takes the form of a pubHcation provided by the U.S. Government. The pubHcation of patents occurs only on Tuesdays that ate not federal hoHdays. At the time of issuance, the patent is assigned a number and made pubHc in a form which allows all interested patties to obtain access to it. 

Issuance of a United States patent transforms a patent appHcant into a patentee, and new concerns may arise relevant to management. For example, the patent should be reviewed to determine formal and substantive correctness. An audit should be taken regularly to determine whether there is a continuing justification to pay the maintenance fees required to keep the patent in force during its effective period. The patentee or patent assignee may have to address concerns of patent infringement or patent vaHdity. 

Initial evaluations of chemicals produced for screening are performed by smelling them from paper blotters. However, more information is necessary given the time and expense required to commercialize a new chemical. No matter how pleasant or desirable a potential odorant appears to be, its performance must be studied and compared with available ingredients in experimental fragrances. A material may fail to Hve up to the promise of its initial odor evaluation for a number of reasons. It is not at all uncommon to have a chemical disappear in a formulation or skew the overall odor in an undesirable way. Some materials are found to be hard to work with in that their odors stick out and caimot be blended weU. Because perfumery is an individuaHstic art, it is important to have more than one perfumer work with a material of interest and to have it tried in several different fragrance types. Aroma chemicals must be stable in use if their desirable odor properties are to reach the consumer. Therefore, testing in functional product appHcations is an important part of the evaluation process. Other properties that can be important for new aroma chemicals are substantivity on skin and cloth, and the abiHty to mask certain malodors. 

Higher order aUphatic quaternary compounds, where one of the alkyl groups contains - 10 carbon atoms, exhibit surface-active properties (167). These compounds compose a subclass of a more general class of compounds known as cationic surfactants (qv). These have physical properties such as substantivity and aggregation ia polar media (168) that give rise to many practical appHcations. In some cases the ammonium compounds are referred to as iaverse soaps because the charge on the organic portion of the molecule is cationic rather than anionic. 

HairC are. Quaternary ammonium compounds are the active ingredients in hair conditioners (31—39,239). Quaternaries are highly substantive to human hair because the hair fiber has anionic binding sites at normal pH ranges. The use of quaternaries as hair conditioners can be broken down into creme rinses and shampoo conditioners. 

Abbreviations of prominent use properties of the various classes of commercial surfactants are shown in Table 1. Antimicrobial activity includes germicidal, bactericidal, and bacteriostatic effects emolliency describes lubrication or a soft feel imparted to skin by surfactants a hair conditioner is a substantive surfactant appHed from aqueous solution to impart a lubricating or antistatic effect and opacifters are used to thicken hand-dishwashing products and cosmetic preparations to convey an appearance of high concentration and to retard solvent drainage from foam. 

Tertiary Amine-Containing Copolymers. Copolymers based on DMAEMA (dimethylarninoethyl methacrylate) in either free amine form or quatemized with diethyl sulfate or methyl chloride have achieved commercial significance as fixatives in hair-styling formulations, especially in the weU-pubhcized "mousses" or as hair-conditioning shampoo additives. This success has occurred because the cationic charge affords substantive resins that strongly adhere to the hair (141). 

PVP/DMAEMA DES quaternary ISP / GafquatBASF/Luviquat 755N/734PQ11 strongly cationic, substantive, mousse and gel hair fixative ingredients... 

Other disazo dyes with good substantivity and high wet-fastness properties on polyamides are Acid Red 114 (40), made by coupling o-toHdine to phenol which is then coupled to G-acid, followed by reaction of the phenoHc hydroxyl group with -toluenesulfonyl chloride, and Acid Blue 113 (41) (metanilic acid — 1-naphthylamine — 8-anilino-1-naphthalenesulfonic acid). 

Direct dyes are defined as anionic dyes substantive to ceUulosic fibers (cotton, viscose, etc), when applied from an aqueous bath containing an electrolyte. Before the discovery of Congo Red in 1884, only mordanted cotton could be dyed. Congo Red [573-58-0] (62) (Cl Direct Red 28 Cl 22120) a primary symmetrical disazo dye, which is made readily from bisdiazotized benzidine and naphthionic acid [84-86-6] (4-arnino-l-naphthalenesulfonic acid), was the precursor of a most important line of dyes, including all shades, derived from benzidine and its homologues. Today, no benzidine dye is produced because benzidine is carcinogenic. 

In order to eliminate the expensive naphtholating and drying operations some further important developments were introduced by Chemische Fabrik Griesheim-Elektron under the names of Rapid Fast, Rapidazol, and Rapidogen combinations (mixtures of substantive coupling components with antidiazotates, diazosulfonates, and diazoamino compounds, respectively). 

Cationic Hydroxyethylcelluloses. These materials are manufactured by Union Carbide Corp. and National Starch and Chemical Corp., marketed under the trade names Polymer JR and Celquat, respectively (47,48). The cationic substituent on Polymer JR is presumably 2-hydroxypropyltrimethylammonium chloride (72). Celquat is presumably the reaction product of HEC with /V,/V-dia11y1-/V,/V-dimethy1ammonium chloride (73). Their primary appHcation is in shampoos and hair conditioners wherein the cationic moiety imparts substantivity to hair. Some typical properties of Celquat resins are given in Table 7. 

After washing with chlorhexidine skin cleanser for 15 seconds, a 99.9% reduction of transient contaminants was achieved (216). Chlorhexidine is sometimes combined with alcohol to achieve the rapid reduction obtained with alcohol and the residual effect of chlorhexidine. It is substantive to the skin, and repeated use results in lower levels of bacteria on the skin. 

Acid Dyes. These are anionic dyes, usually containing sulfonic acid groups, that are substantive to wool, other protein fibers, and polyamides when dyed from an acidic dyebath. The lower the pH the more rapid the dyeing, and exhaustion efficiency is enhanced by increased acidity. 

Mordant Dyes. This group includes many natural as well as synthetic dyes. They have no or low substantivity for textile fibers and are therefore appHed to ceUulosic or protein fibers that have been treated (mordanted) with metallic oxides to give points of attraction for the dye. The dye... 

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