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In the continuation of the work previously described, experiments were conducted, according to the general plan already described, to determine the effects of benzoic acid and benzoates upon health and digestion. This investigation is of special importance because of the opinion held by many manufacturers, food officials, and consumers that benzoic acid and benzoates are probably the least harmful of the preservative substances employed. It is believed that for this reason there has been a very large increase in the use of these preservatives in the United States in the last few years, with a corresponding decrease in the amount of other preservative substances employed. It has also been claimed that there can be no reasonable objection to the use of benzoic acid by reason of its natural occurrence in many food products, either in traces or in considerable quantities. Among the products cited the cranberry occupies the most prominent position because of the notable amount of benzoic acid it contains. These considerations, however, had no determining influence on the choice of this substance for the experimental work, inasmuch as it was included in the original scheme which was prepared before the experimental work on preservatives previously reported was begun.

This research aimed at lowering the non-volatile matter (NVM) of long oil alkyd (LOA) resin to meet the resin requirements in producing Hi-gloss paints. The research also aimed to assist Hi-gloss paint manufacturers who require solid resin content below 70%.

The research utilised both the document review and experimental methods. The experimental method, which involved the blending process, was used in lowering the NVM of LOA resin, whereby eight experiments were conducted as reputations to obtain accurate data and results. A factorial design was used in the design of the experiment (DOE), where three factors were required to be evaluated: specific gravity, viscosity and NVM and two levels were required: weight of LOA and white spirit.

The NVM of LOA resin was successfully lowered, and different shades of paint were produced for reliability testing. The quality parameters of Hi-gloss paints that used the modified LOA were all found within the company's specifications compared to those with unmodified LOA, where some parameters were either above or below the specifications. However, all samples with the NVM of LOA used below 50% were found to be poor in terms of quality during the reliability testing. So, if the company had used the modified LOA resin in the production of Hi-gloss paints, it would have potentially saved 18,925.2 kg and 9,446.4 kg, respectively, of LOA just in producing Hi-gloss black and white paints only. Moreover, the cost of 1 kg of LOA is $2.3, which is equal to Tanzanian Shillings (Tshs) 5,290. The company would have potentially saved Tshs 100.114 million Tshs and Tshs 49.97 million Tshs in producing Hi-gloss black and white paints, respectively, making a total of Tshs 150.08 million per year. This was counted as a loss during that year because they did not use LOA resin with 50% NVM in production.

This study focused on LOA resin used in producing Hi-gloss paints. The study also did not consider other categories of alkyd resins used in producing paints and varnishes e.g. epoxy resin and short and medium oil alkyd resins.

This is probably the first alkyd resin improvement study conducted using white spirit as Tanzania's main agent or material. The study utilised vegetable oils such as coconut, sunflower and tobacco seeds.

Solvents, as the name implies, may be considered as the inert components of chemical reactions, purification, or cleaning processes, emerging chemically unchanged but contaminated with dissolved impurities and unsuitable for re‐use without subjection to a recovery process.

The acute shortage coupled with tremendous increase in cost of various solvents used by paint industry and pollution becoming a serious concern has resulted in intensive study of water‐borne coatings. Water‐borne coatings ideally meet the needs for coating systems which do not cause atmospheric pollutions and at the same time help in conservation of precious and renewable petroleum resources. Many research workers have developed water‐soluble epoxies, alkyds and acrylics to make water‐based surface coatings.

Water soluble epoxy resins were prepared from epoxy resin, linseed fatty acids, maleic anhydride, trimellitic anhydride, maleinised dehydrated castor oil and maleopimaric acid. Pigmented coating compositions for anodic electrodepositions were prepared from water soluble epoxy resins using red oxide of iron and zinc phosphate as pigment. The electrodeposition parameters such as voltage, time, solid content and pH value were optimised. The mechanical and chemical film properties of different electrocoating compositions were studied.

The commercial success of electro‐deposition of aqueous coating is mainly concerned with the development of water‐soluble film forming polymers. The field of these water‐soluble polymer systems for surface coating application is growing rapidly and expanding vigorously and they are destined to play a leading role in the near future. This may be mainly attributed to regulations on emissions, environment and ecology. In doing so, the electrodeposition technique offers a remarkable assistance to these systems at comparatively low cost, low energy requirement and high utilization efficiency. Research workers have done work on water‐soluble alkyds, epoxies and acrylics.

The annual report of the Ministry of Health for the year ended March 31st last states that, during that period, 120,617 samples were analysed under the Acts. This is the largest number ever recorded. A total of 7,044 samples were reported as adulterated or not up to standard, or 5.8 per cent., compared with 6.5 per cent. for the previous year. Of 62,507 samples of milk, 4,625 or 7.4 per cent. were not up to standard or adulterated. Eighty samples were contaminated by dirt, against 131 the previous year. Colouring matter was detected in 41 samples, one of which also contained 50 per cent. of added water. One sample of dried milk consisted of soya bean, cane sugar, milk sugar, and a vegetable oil. Eighty‐two of the butter samples consisted wholly or partly of foreign fats. One case was found of a grocer selling unlabelled margarine as “butter mixture.” When a purchaser complained of gritty bread, it was found to contain 0.12 per cent. of sand, thought to have been due to mill sweepings having been introduced into the flour. Custard powders were adulterated by the presence of acid dyes, while egg powders were found to contain no eggs. One egg powder sample consisted of 63 per cent. of flour, 20.6 per cent. of bicarbonate of soda, and 16.4 per cent. of tartaric acid, with a trace of colouring matter. Foreign fats, cornflour, or other starch, traces of lead, and oxide of iron were found in samples of chocolate. One case was reported of the use in chocolate rock of commercial burnt sienna containing an excessive quantity of arsenic. A number of samples of sponge cakes were found to contain boric acid, and traces of this preservative were also detected in samples of other foods, including ice‐cream, sponge sandwich, meat pie, fish paste, potted shrimps, and sausages. Powdered talc in small quantities still continues to be introduced into rice, and three cases are reported in which an article sold as sago was found on examination to be tapioca. Seven hundred and seventy‐three samples of sausages were examined, and 18.5 per cent. were found to be adulterated by the addition of preservative (usually boric acid). A consignment of tea containing iron filings was seized and destroyed. Eight grains of iron filings to the pound and 12 per cent. of dust were found in another lot of tea, while in a third sample the tea dust contained 8 per cent. of mineral matter. Adulterated samples of ground ginger and ground cinnamon were found to contain mineral matter, petroleum products were found in turpentine, and traces of lead and cornflour in cream of tartar.

In reference to the administration of the Sale of Food and Drugs Acts by the various local authorities in England and Wales during the year 1908 the following remarks appear in the recently issued report of the Local Government Board for that year. “Our attention has been drawn to the practice which has been adopted recently by certain local authorities of inviting applicants for the office of public analyst to state the terms upon which they are prepared to accept the appointment. We consider the offering of such appointment ‘on tender’ as open to strong objection, and we trust that the practice will be discontinued.”

Water soluble epoxy resins were prepared from male‐opimaric acid, linseed fatty acids and epoxy resin. The methylated urea formaldehyde resin and melamine formaldehyde resin were also prepared for curing purposes. The pigmented coating compositions were prepared from water soluble epoxy resins, red oxide and iron and zinc phosphate. These coating compositions showed good water resistance, acid resistance, alkali resistance and lubricating oil resistance.

The resin activators' type and quantity in a solder paste have a significant effect on reflow behaviour. These interact with the effects of the oxygen content of the reflow atmosphere and the condition of the surfaces to be joined. While these parameters might be expected to influence solder paste reflow behaviour, more subtle effects related to the physical characteristics of the resin/solvent solution have also been observed.