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Industrial progress is in large measure a function of the scientific understandings inherent in a given body of technology. It is, of course, true that technology can be developed empirically and much of it has been. It is also true, however, that technology based on scientific understandings is in practically every instance more effective. If only empiricism is involved there inevitably comes a time when technological progress ceases. It is for this reason that scientific studies in the coatings industry must be continually encouraged.

The overall concept of permeability in paint films has been reviewed by Boxall and von Fraunhofer [Paint Manufacture, 45, November (1975) p. 14] who point out that as a result of their research the efficiency of anti‐corrosion pigments is closely related to water permeability in the paint film. Indeed, pigments like basic zinc chromate are only cabale of inhibiting substrate corrosion when in contact with water. This raises an interesting question relative to the effectiveness of anticorrosive pigments in highly water‐resistant films. Of course, as the authors point out, all films have a degree of permeability. No doubt this permeability increases as the film ages and, accordingly, the anticorrosive pigment may become more effective as the film ages and loses some of its protective properties.

Where does the coatings industry look for technology which borders on its own and from which it might derive useful leads and ideas? The coatings industry basically depends on the formation of films. Basic to the idea of coatings is the concept that there must be a film and that this film must derive from the vehicle in the coating. To be sure, the film does not represent the entire coating, but it is the sine qua non; and without a film the coating will neither decorate nor protect. There are a host of other technologies that depend on film formation. When the word ‘film’ is mentioned, adhesives and printing inks come to mind, for these technologies also could not exist without the all‐important phenomenon of film formation.

Related even more closely to the coatings industry's technology are printing inks. Like coatings, inks comprise a combination of vehicles, pigments, and small percentage additives Inks do not serve a protective function in the same way that coatings do but they must, on the other hand, adhere to the substrate and they must certainly frequently be decorative. Conversely, practically all inks are applied in a “factory”, analogous to factory‐applied or industrial coatings. The analogy goes even further in that the application is done by highly automated equipment at rapid speeds, although it must be pointed out that inks are applied much more rapidly than most coatings.

Electrocoating paints enjoyed a sales volume of $26 million in 1974 and it was predicted that this would double by 1978 Chemical & Engineering News [52, August 26 (1974) p. 10]. The article describes some of the advantages of electrocoating including the fact that paint particles penetrate cracks and flaws in the metal because of electrical attraction. With dipping or spraying, on the other hand, the paint tends to bridge these areas rather than to duplicate the precise profile of the subtrate. Another advantage of the electrocoating process is its ability to achieve a coating of uniform thickness for this is controlled by the extent of the charge of the object being coated. Efficiency of the process is demonstrated by the fact that more than 95% of both the resin and the pigment are utilized as compared with 80% for other dip procedures and as little as 50% for spray coating methods. Two of the disadvantages described include the fact that it can be used only on electrical conductors such as metal and that it shares in common with other dip procedures considerable difficulty and expense when it comes to colour changes.

This chapter explores how the irruption of plastic materials in contemporary society, in the same way that it facilitated a wide range of human activities, eventually degenerated into a global danger through the contamination of rivers and seas, damaging the human food chain. In doing so, the historical background of this situation has been outlined. Moreover, the countries and areas at present that have polluting plastic substances and those that can be most easily recycled is highlighted. It should be noted that it is precisely in the area of recyclability where most hopes have been placed to counteract plastic contamination aimed at avoiding single-use plastic products. Subsequently, the different positions adopted by the members of society on this problem have been described and, by way of example, the state of the situation in a specific country, Spain, has been summarised.

In 1978 the plastic bottle was introduced nationwide. In the thirteen years since that historic (and some say environmentally devastating) occasion, the consumer increasingly has embraced plastic packaging. Each American uses about 190 pounds of plastic per year, according to Earthworks Group, and about 60 pounds of it is discarded within minutes or seconds after opening. The plastic bottle is king. American consumers use 2.5 million plastic bottles every hour.

In 1987, Campbell Soup Company introduced the Souper Combo, a line of frozen soup and sandwiches. Melvin Druin, vice‐president for packaging, called it “the perfect combination of old‐fashioned good taste and today's convenience. No mess. No fuss. Easy to use. All you have to do is clean your spoon. Everything else just throw away.” Unfortunately, the multi‐layered plastic‐coated packaging does not just disappear when thrown away. Plastics packaging, particularly from convenience products, has become a waste disposal nightmare. Garbage, an environmental magazine, gave the Souper Combo an “in the dumpster” award, saying, “It's precisely the kind of product that's created the municipal landfill monster.”