Antimicrobial Fibres

Patent Ntrmber US 5405644 A 19950411 PROCESS FOR PRODUCING ANTIMICROBIAL FIBRE... 

Gentamicin sulfate release from antimicrobial fibres was carried out by submergiiig the fibre-gentamicin sulfate complex into a physiological solution (0.95% NaCl). After that, gentamicin sulfide release was monitored. Gentamicin sulfate release fix>m the fibre (physiological solution) was measured in vitro by a Shimadzu UV-260 UV-vis spectrophotometer. 

Antimicrobial agents may adversely affect the light fastness of nylon dyeings or cause yellowing of the fibre. The six antimicrobial treatments listed in Table 10.51 have been... 

Despite the long list of requirements, a variety of chemical fmishes have been used to produce textiles with demonstrable antimicrobial properties. These products can be divided into two types based on the mode of attack on microbes. One type consists of chemicals that can be considered to operate by a controlled-release mechanism. The antimicrobial is slowly released from a reservoir either on the fabric surface or in the interior of the fibre. This Teaching type of antimicrobial can be very effective against microbes on the fibre surface or in the surrounding enviromnent. However, eventually the reservoir will be depleted and the finish will no longer be effective. In addition, the antimicrobial that is released to the enviromnent may interfere with other desirable microbes, such as those present in waste treatment facilities. 

Research into controlled-release antimicrobials continues with organo-silver compounds and silver zeolites, which are promising candidates for textile finishes. Silver ions, for example, incorporated in glass ceramic, have a very low toxicity profile and excellent heat stability. These principles are also used for fibre modification, an alternative to the antimicrobial finishes with high permanence. In recent years a variety of antimicrobial modified fibres have been developed, including polyester, nylon, polypropylene and acrylic types. An example of these fibre modifications is the incorporation of 0.5-2 % of organic nitro compounds... 

A new and novel approach to bound antimicrobials was recently introduced. Cotton reacted with methylol-5,5-dimethyldyantoin is then treated with hypochlorite to form chloramines in the fibre (Fig. 15.3). These chloramine sites have antibacterial activity and can function as renewable antimicrobial agents by continued treatment with hypochlorite through household bleaching and washing... 

Prevention Antimicrobial finishes or fibre modifications hinder the decomposition of sweat Permanent with respect to washing and dry cleaning, especially in the case of fibre modification, restricted to smells from sweat decomposition, therefore only for clothing with skin contact. 

One way to prevent the development of unpleasant odours that originate from the decomposition of sweat are antimicrobial finishes or bacteriostatic modified fibres. They prevent the decomposition of perspiration by bacteria to bad smelling products as described in Chapter 15. 

Symptomatic diverticular disease often responds to an increase in dietary fibre, and addition of a stool bulking agent. Antispasmodic drugs are helpful in controlling the pain of colon spasm but antimotility drugs encourage stasis of bowel contents, increase intracolonic pressure, and should be avoided. Diverticulitis requires treatment with broad spectrum antimicrobials for 7-10 days (e.g. 

There is a wide range of chemicals suitable for antimicrobial application to fibre finishes. However, for practical reasons, amine-based chemicals, especially quaternary amines are used most because they can show multifunctionality as mentioned in Section 5.4.1. 

The preparation of rrltrafine antimicrobial cellnlose acetate (CA) fibres with silver nanoparticles by direct electrospinning of a CA solution containing low levels of silver nitrate and characterised by viscosity, strrface tension and conductivity, followed by photoreduction using UV irradiation, is described. The fibres were characterised by SEM, TEM, XPS arrd artfirrticrobial activity and the resrrlts are discussed. 24 refs. 

Cetylpyridinium chloride (CPC) was used to form ionic bonds with Acrilan (acrylonitrile copolymer) woven fabrics in order to confer antimicrobial functions to the fabrics. The finished fabrics showed good efficacy against Escherichia coli and the washing durability of the antimicrobial properties was excellent. The CPC uptake on the Acrilan fibres depended on the pH during the finishing process, concentration of the CPC and the finishing temperature. High pH and temperatures were... 

JMAC antimicrobial masterbatches are described. The products are based on the controlled release of silver ions. A silver chloride/titanium dioxide composite particle releases silver ions on contact with water and then maintains an equilibrium concentration in solution, releasing more ions as required to give effective preservation. Its antibacterial performance in PP mouldings, in thin section PE, itylon, PETP and PP fibres is reported. JMAC masterbatches are available in most polymeric carriers including PE, PP, polystyrene, ABS, PETP and nylon, with typical addition rates of around 1%. 

Patent Number US 5853883 A 19981229 POLYOLEFIN FIBRES CONTAINING ANTIMICROBIAL SILOXANE QUATERNARY AMMONIUM SALTS... 

These fibres are made from a melt-extrudable composition containing a polyolefin and an antimicrobial siloxane quaternary ammonium salt, which can be a trisiloxane having a pendant quaternary ammonium group and a molec. wt. of from about 600 to 1,700 or an ABA-type siloxane having a polydispersity of up to about 3.0 and a weight-average molec.wt. of from about 800 to 2,000 in which a central moiety is terminated at each end by a quaternary ammonium salt group. The anion can be one, which does not adversely affect the heat stability of the salt. 

A thermoplastic composition containing a polyolefin and an additive is melted and extraded through multiple orifices to form streams of molten composition, which are cooled to form fibres. The additive is an antimicrobial siloxane quaternary... 

An antimicrobial agent containing at least one of an oxide solid solution of the formula given and a hydrotalcite of the formula given, the above antimicrobial agent being free of, or almost free of, toxicity, excellent in heat resistance and weatherability, less expensive and excellent in dispersibility in resins, mbbers and fibres. 

Disclosed are dry, disposable, polymeric antimicrobial-applying products having sustained-release antimicrobial activity. They corrsist essentially of a polymeric material, such as a natrual polymer, synthetic polymer or mixture thereof, in the form of fibres, yarrrs, woverr, non-woven and knitted fabrics, sheets and films, and an amine salt antimicrobial agent, which is releasably impregnated into... 

---