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In aqueous alkaline ink media aluminium pigments react with the evolution of hydrogen, whereas the more noble copper and brass pigments react by the absorption of oxygen, which can be measured gas‐volumetrically. These different corrosion reactions can be inhibited with addition of certain binders for printing inks, such as styrene‐maleic acid resins, maleic resins and to some extent styrene‐acrylate resins. So, certain ink resins inhibit corrosion reactions of different noble metal pigments in a reducing hydrogen atmosphere (aluminium) as well as in an oxidizing oxygen atmosphere (copper and brass). The overall best resin is that with the lowest acid number. Atomic absorption spectroscopy measurements showed that a lower acid number pruduces a lower solubility of copper and zinc in the medium.

A lamellar zinc pigment reacts in aqueous alkaline media (e.g. water‐borne paints) with the evolution of hydrogen. This corrosion reaction can be inhibited by certain surfactants. The most important structural part of the examined surfactants is the hydrophilic group; only anionic phosphate or phosphonate hydrophilic groups are effective corrosion inhibitors. Surfactants with carboxylate, sulfonate, amphoteric, cationic and non‐ionic hydrophilic groups are ineffective. There seems to be also an influence of the hydrophobic group of the surfactants because a partial ester of phosphoric acid with a fluorinated hydrophobic group was the most effective corrosion inhibitor in this study.

A severe problem with water‐borne paints containing aluminium or zinc pigments is hydrogen corrosion of these metals in the aqueous alkaline paint media. The subject of the present study is the examination of corrosion inhibition of aluminium and zinc pigments in aqueous alkaline media by different amino and polyamino acids. Aspartic acid inhibits this corrosion reaction of aluminium pigment only at pH 8 (protection factor 96 per cent) whereas polyaspartic acids do not. In contrast, aspartic acid stimulates the corrosion reaction of zinc pigment whereas polyaspartic acids show a moderate corrosion inhibiting effect. So, corrosion inhibition by aspartic and polyaspartic acids is completely different on aluminium and zinc pigment.

Aluminium and zinc pigments corrode in aqueous alkaline paint media with the evolution of hydrogen. Maleic acid‐styrene‐acrylic ester copolymers were synthesized by copolymerisation of maleic acid anhydride, styrene and different (meth)acrylic esters. Three acrylic esters (ethyl, n‐butyl, n‐hexyl) and two methacrylic esters (n‐dodecyl, n‐octadecyl) were used; the copolymers with long‐chain acrylic esters are amphiphilic. Additionally, a commercial (non‐amphiphilic) styrene‐maleic acid copolymer (SMA) with similar molecular mass and acid number was tested. The corrosion reaction of aluminium and zinc pigments in aqueous alkaline media can be inhibited by addition of these copolymers. But aluminium and zinc pigments react completely differently with the examined copolymers. With addition of the amphiphilic maleic acid‐styrene‐acrylic ester copolymers to aluminium pigment dispersions the evolved hydrogen volumes decrease with increasing chain‐length of the acrylate monomer in the copolymers, whilst with zinc pigment the hydrogen volumes increase, which is just the opposite compared with aluminium. Furthermore, there exist mathematical correlations between the number of carbon atoms of the ester alcohol of the acrylate monomer in the copolymers and the hydrogen volumes evolved.

Aluminium and zinc pigments react in aqueous alkaline media (e.g. water‐borne paints) by the evolution of hydrogen which can be measured gasvolumetrically. Certain organic heterocycles are well‐known corrosion inhibitors for different metals. The six different heterocyclic compound which were examined inhibited the corrosion reaction of zinc pigment in aqueous alkaline media. The most efficient inhibitors were 1H‐benzotriazole at pH 8 and 10 and 2‐(5‐aminopentyl)benzimidazole only at pH 10. In contrast, with addition of all heterocycles there was no corrosion inhibition on aluminium pigment. This complete difference in the corrosion inhibiting effect of the heterocycles with respect to the two different metal pigments can be explained with Pearson’s “Principle of Hard and Soft Acids and Bases”.

Zinc pigments corrode in aqueous alkaline paint media (e.g., waterborne anticorrosive paints) with the evolution of hydrogen. Paint resins inhibit this corrosion reaction at a pH value of 8 more effectively than at pH10. An increase of resin addition effects a decrease of hydrogen evolution (i.e., corrosion inhibition increases). The corrosion reaction of spherical zinc dust can be nearly completely inhibited with the addition of a certain epoxy ester resin (EPE 1). The epoxy ester resin looses its corrosion inhibiting properties after film formation, because of loosing its mobility, which seems to a be requirement for corrosion inhibition. So, zinc dust is inhibited in the liquid waterborne paint but still shows its sacrificial action in the solid primer coating.

The concept of psychic distance has gained widespread theoretical recognition as a predictor of export behaviour. However, the empirical validation of the concept remains patchy and contradictory in terms of the results obtained. Consequently, this paper attempts to shed fresh light on the empirical usefulness of the psychic distance concept. First, a wider assessment base is offered through the development of two new US samples. Subsequently, the US findings are compared with previous empirical evidence from Japan, Germany, Finland and Austria. Taken collectively, the results call into question the practical value of the current operationalisation of psychic distance in explaining export behaviour and provide pointers for required conceptual and measurement improvements.