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This paper aims to isolate fungal strains producing natural colours, explore their application as colourant in paints and develop cost-effective durable natural paints.

Fungal strains producing natural colours of different shades were isolated. Colourant production was carried out by fermentation method. Natural lime, milk, oil-in-water emulsion paints using natural microbial colours and eco-friendly ingredients were prepared. Bio-paint applications were carried out and evaluated.

Our results indicate that microbes in general and fungi in specific represent dependable source of variety of natural colours, and cost-effective durable natural paints can be prepared with commonly available natural ingredients using scientific information based on history of paints.

Natural colours are gaining importance because of their use in health, nutrition, pharmaceutical, textile and environmental applications. Nature is quite rich in several types of colourants. Chemical synthesis of synthetic dyes is complex and not environmental friendly. Microbial dyes manufactured can evade inherent environmental problems of synthetic dyes and offer significant opportunity as a colourant in paints. However, only generally regarded as safe microbial strains are to be considered for colour production.

Choosing natural alternatives to protect the health and environment is the need of hour. Fungal colourants are relatively more stable and robust and offer significant opportunity as a colourant in paints. Cost-effective durable natural paints can be prepared using selected stable fungal colourants with commonly available natural ingredients. High diversity of rich and complex natural colourants can be obtained from microorganisms. With the available techniques of fermentation, natural colours can be produced in large quantities of on an economically viable scale and explored for their applications.

Bio-paints are eco-friendly natural paints, low volatile organic compounds (VOC) paints or organic paints alternate to conventional paints. Most of these natural paints are durable, breathable, prevent moisture problems, contribute to a positive room climate, use safer technology and are less energy-intensive than conventional latex paints to produce. These paints improve indoor air quality and reduce urban smog and offer beneficial characteristics such as low odour, excellent durability and a washable finish.

Many of the old art works that still survive today are a tangible proof and evidence of beauty and durability of natural paints. Organic materials used in these paints include natural pigments of mineral, plant and animal origin and other raw biodegradable ingredients. Successful commercialisation of many microbial pigments for food and textile applications is reported in literature. Therefore, present research work aims at developing natural paints using microbial pigments and recipes that have been successfully used by people for years.

The purpose of this paper is to study the colour stability and water content resistivity of the green colour coating paint film (consisting of chlorophyll) during exposure to ultraviolet A (UV-A).

The natural green dye was prepared by immersing Cassia alata L. leaves in absolute ethanol. The extract was prepared in two batches of dye samples where one of it was a pure dye and the other was added with 3 Wt. % Cu(NO₃)₂ as an additive. Polymer blend as a binder was prepared by mixing poly(methyl methacrylate) (PMMA) and commercial acrylic polyol. The blended polymer was mixed with the natural dye in a specific ratio and applied as coating paint film on glass panel surfaces. The visible spectrum stability (colour stability) and water content resistivity of the coating paint films during exposure to UV-A were monitored.

Addition of Cu(NO₃)₂ had improved the colour stability of the coating paint film. Fourier transform infrared spectroscopy analysis showed that both coating paint films do not absorb water and are resistive to water content.

The ability of Cu(NO₃)₂ as an colour stability additive to the natural green dye applied in the coating paint film.

The coating paint film developed in this work is suitable to be applied on glass substrates.

The colour stability of the coating paint film was analysed by using the reflectance spectrum.

In order to find a way to combine traditional culture with modern living needs, taking “Chinese painting” as the breakthrough point, through the study of the development process and artistic characteristics of Chinese painting, four aspects of classical philosophy, natural landscape image, brush and ink composition artistic conception, and abstract aesthetic conception contained in Chinese painting are summed up. The results of the study provide enlightenment for contemporary residential landscape design, and summarize the methods of creating Chinese paintings in residential landscape design. Thus, a residential landscape model with the characteristics of “Chinese painting” is found out.

The purpose of this work is to investigate the influence of curcumin dye natural colorant on adhesion, mechanical, thermal and electrochemical properties of blend poly (methyl methacrylate) (PMMA) – acrylic polyol.

Extracted curcumin yellow dye colorant from Curcuma Demostica was mixed with PMMA‐acrylic polyol blended polymer in the volume ratios of 9:1, 8:2 and 7:3. The mixtures were applied on pre‐treated cold‐roll mild steel panels. All of the paint coating samples were subjected to potential time measurement (PTM), rapid impact deformation, differential scanning calorimetry (DSC), cross hatch and Fourier transform infrared spectroscopy (FTIR) tests.

The addition of curcumin dye colorant was able to improve the adhesion, flexibilities and resistance against electrolytes penetration of the blended poly (methyl methacrylate) (PMMA) – acrylic polyol polymer paint system. Cross hatch test studies showed that high amount of curcumin dye colorant (AP30 paint system) had the lowest peel‐off coating area from the substrate. The FTIR test had confirmed the high concentration of hydroxyl group in the AP30 sample. The hydroxyl group was able to promote hydrogen bonding between coating substrate interface. The AP30 sample had the highest coating flexibilities when tested with rapid impact test. This was due to the lowest glass transition value T_g which indicated lowest cross linking density in the coating molecules structure. In the PTM test, AP30 paint system had shown the highest rate electrolytes penetration within the AP sample.

The composition of curcumin dye colorant in the polymer blend is limited from 10 percent to 30 percent pigment volume concentration. Increasing the amount of lawsone pigment will result inhomogeneous mixtures.

The AP paint system is suitable for interior applications. This paint system has to be mixed with suitable additive materials to improve its performance for exterior purpose.

This paper is an appraisal using the life cycle assessment (LCA) of paint repair for heritage buildings based on the green maintenance model.

Calculation procedures of green maintenance model within cradle-to-site boundaries of LCA approach were undertaken. The calculations evaluate embodied carbon expended from paint repair of Gunongan, Banda Aceh and Melaka Stamp Museum, Melaka.

The findings show that the type and number of coats applied will determine the lifespan of the paint. The lifespan of paint influences the frequency of its repair, thus affecting environmental maintenance impact (EMI).

Green maintenance model is not confined to heritage buildings and can be applied to any repair types, materials used and building forms. The model supports and stimulates research dedicated to the sustainable development of cultural heritage. This results in the attainment of environmentally focused conservation, promoting sustainable repair approach and inculcating sustainable development of the historic environment.

Green maintenance model highlights the efficiency of repair options that may be adopted for heritage buildings, thus cultivating skills and knowledge in cultural heritage and sustainable development.

The paint repair appraisal of heritage buildings in different countries and localities, which share similar tropical climate, can be undertaken. It demonstrates how different approaches by relevant agencies to the paint repair of heritage buildings impact on embodied carbon expenditure.

The problems associated with preserving the steel sheeting of water‐sealed gasholders have been known for some time. Various techniques have been adopted, e.g. protective painting, oil filming and sacrificial anodes. This paper deals with painting, and the two groups of paints used in the experiments were chosen for (1) their blister‐suppressing qualities and (2) their good adhesion and water resistance.

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.

Paint imports rise After severe problems in the early 1980s, the paint and printing inks industry is beginning to show some signs of improvement. Average sales for the industry grew by 21.4% over the first half of the period covered, and then by 45.2% over the second half, states the latest ICC Business Ratios report on paint and printing inks. There are now signs of a slackening off in this expansion. At the same time, imports have been steadily increasing, and now take a larger share of the home market. The level of exports has risen, but not by the same rate as imports. This increasing invasion of the domestic market will cause difficulties for the UK producers — as we have seen elsewhere when it is too late!

This chapter deals with five key themes: the objectives for companies and the attitudes and buying behaviour of consumers as concerns sustainable development, the firm’s strategies for reducing energy costs and waste, the challenges of bringing all actors in the supply chain into line, the firm’s supply policy in response to consumer demand and the technical, organisational and communication challenges surrounding the environmental impact of products. It then considers at the role of governments and NGOs in companies’ approaches towards sustainable development strategies before finally outlining the future prospects for these strategies.

Trials to develop environmentally friendly marine paints based on natural materials as replacement for copper and tin compounds for fouling and marine corrosion control.

Green algae, tubeworms in dead powder form and garlic were used as natural anti‐fouling components in the paints developed. Electrochemical technique was employed for testing the potential of both tubeworms and garlic in terms of inhibition of steel corrosion in seawater. Marine paint formulations containing each of the three selected natural materials were applied onto PVC and un‐primed steel surface, which were immersed in natural seawater for the assessment of their anti‐fouling and anti‐corrosion properties. The results of visual assessment and seawater analysis were also used for such an evaluation.

Tubeworms act as mixed type inhibitor while garlic affects the potential cathodic process of steel in seawater. Tubeworms‐based paint, with 25 per cent in the dry paint film, could protect steel surface from marine corrosion up to 7 months. The paints containing algae and garlic, and the corresponding algae/garlic free paints, resisted slime film formation. Steel and PVC coated surfaces with paint containing algae showed the best anti‐fouling potential within the prepared series.

The investigation only involved the application of the dead form of green algae and tubeworms as effective pigments in the developed paints. It is recommended that further research should focus on extracting and identifying the active components in each organism against fouling and marine corrosion.

The paint formulations developed (containing 25 per cent by weight tubeworms in the paint film) could be used to protect un‐primed steel surface against fouling and marine corrosion for a reasonably long duration.

The application of one paint formulation on un‐primed steel surface for its protection from both fouling and marine corrosion is novel. The electrochemical studies of steel in natural seawater in presence of tubeworms and garlic are original.