NOVELTY - Substituted ammonium carboxylate compounds are new.    USE - The compounds (I) are useful as biocides, for preparation of a composition selected from solutions, suspensions, emulsions, pastes, ointments, gels, creams, lotions, powders, oils, waxes, pencils, shampoos, deodorants-creams, gels, deodorant sticks, roll-ons, aerosols, sprays, pump sprays or lacquers; in the form of cosmetic formulations, medicinal products, paints, inks, home care products, animal care products, products for personal and work hygiene, contact lenses, chromatography materials, medical equipment, protective topicals, lacquers, textiles, coatings and/or plastics; and the compounds (I') are useful as antibiotics (claimed). The microorganisms against which the biocide compounds are useful include bacteria (including gram positive and gram-negative bacteria), yeasts, fungi and viruses e.g. Staphylococci, Micrococci, Escherichia, Pseudomonas, Bacilli, Salmonella, Shigella, Porphyromonas, Prevotella, Wolinella, Campylobacter, Propionibacterium, Streptococci, Corynebacterium, Treponema, Fusobacterium, Bifidobacterium, Lactobacillus, Actinomyces, Candida, Malazessia, Aspergillus, and herpes simplex 1 and 2. The compounds are useful for producing antimicrobial activity to inhibit or sooth irritation, inflammation, formation of acne or excretion of sebum; to improve skin and hair conditions, reduce hair loss, produce anti-aging properties or act as antioxidants against the harmful effects caused by oxidants such as reactive oxygen species, and light (visible, UV, or infrared); and as disinfectants in human hygiene biocidal products, as private area and public health area disinfectants, in veterinary hygiene biocidal products, as food and feed area disinfectants, as drinking water disinfectants or as preservatives like in-can preservatives, film preservatives, wood preservatives, fiber, leather, rubber and polymerized materials preservatives, masonry preservatives, preservatives for liquid-cooling and processing systems, slimicides, preservatives for food or feedstocks, and preservatives for cosmetics. The hair conditions include improvements in hair gloss, hair volume and elasticity, stability of natural and artificial hair colors, and inhibition or camouflage of hair-graying. The skin conditions include improvements in skin barrier function, skin hydration, skin oxidation status as well as in support of wound healing process; are also useful to prevent undesired body odors by antimicrobial activities against e.g. bacteria that decompose sweat; and for providing or boosting pigmentation control activities on skin and hair such as tanning and lightening activities. The medicinal products include e.g. antimicrobial cleansers, soaps, anti-fouling and antimicrobial paints, antimicrobial wallpapers, antimicrobial dressings and plasters, prostheses and bone cement with antimicrobial activity, dental fillings, dental prostheses, formulations against gastrointestinal infections, active coal, antimicrobial cat litter, antimicrobial diapers, tampons or sanitary towels, ambient fragrances for rooms or cars, formulations for oral or body care, absorbent pads, air conditioning (filters and ducts), air inflated construction (air halls), agricultural and mulch films, all purpose adhesives, appliances and equipment, appliance adhesives and sealants, aprons, artificial leather, artificial plants, artificial wood, plastic lumber, astroturf, and automobile parts. The compounds (I) are also useful as ionic liquids as solvent or solvent additive, phase-transfer catalyst, extractant, heat-transfer medium, surface-active substance, plasticizer, flame retardant, supporting electrolyte or additive in electrochemical cells.    ADVANTAGE - The compounds (I) have unique properties such as are water soluble, thermally stable, readily biodegradable and are effective as biocides. The compounds also present ionic liquids or liquid salts. The compounds as biocids are useful against microorganisms including bacteria (including gram positive and gram-negative bacteria), yeasts, fungi and viruses. The ionic liquid compounds (I) can be used for inhibition of growth and/or progeny of microorganisms in order to preserve compositions. The ionic liquid compounds (I) show good microbiocidal activity by reproducibly decreasing number of germs in medium, particularly number of microorganisms can be decreased to zero over time period of 3 hours (starting with an inoculum of 105 microorganisms/ml and a verum test concentration of 1%). Even yeasts and fungi can be eliminated within that time frame or even faster.    DETAILED DESCRIPTION - Substituted ammonium carboxylate including compounds of formula (NR'R1R2R3)+ (R4-COO)- (I) excluding N,N,N-trimethyl-2-hydroxyethylammonium hexanoate, and compounds (I') comprising N-ethyl-N,N-dimethyl-2-methoxyethylammonium acetate, and N-ethyl-N,N-dimethyl-2-hydroxyethylammonium propionate; are new.    R'=alkoxymethyl, alkoxyethyl (both having 1-4C linear or branched alkoxy), hydroxymethyl, hydroxyethyl, hydroxypropyl or hydroxybutyl;    R1-R3=1-4C linear or branched alkyl;    R4=5-11C linear or branched alkyl.    INDEPENDENT CLAIMS are included for the following:    (1) preparation of the compound (I);    (2) composition (C1) comprising: at least one compound (I);    (3) preparation of the composition (C1) involving: mixing at least one compound (I) with a carrier and optionally with further active compounds or auxiliaries;    (4) use of the compounds (I') as antibiotics.