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This paper outlines the composition of water soluble fluxes for the electronics industry and their methods of use when wave soldering and reflowing tinned coatings and solder pastes. Process optimisation is facilitated by the Taguchi method. Three types of cleaning machinery are evoked, with varying results. It is shown that the energy/time relationship is important to ensure adequate cleaning quality. A number of fallacious arguments are debunked. Methods of water purification and the problems of effluent treatment for all sizes of installation are addressed. Doubt is expressed as to the viability of closed‐circuit water recycling except for the largest installations or where exceptional conditions prevail. It is shown that water soluble fluxes and their subsequent aqueous removal are unlikely to make any significant contribution to the Greenhouse Effect. The overall cost of their use is substantially similar to that of rosin fluxes with CFC‐113 azeotropes at 1986 prices. Cleanliness control under production and laboratory conditions is discussed with reference to both ionic contamination testing, including its use for SMDs, and SIR analysis, especially at low voltages, including non‐destructive production SIR testing. Reliability of the assembled circuits is shown to be at least as good as that with more traditional soldering and cleaning methods, frequently better, and this is the case even for military and aerospace applications. The paper concludes that, now that quality water soluble solder pastes are available, this method is most likely to become the workhorse for the majority of electronics applications.

Argos Electronics Ltd are pleased to announce the appointment of David E. Skertchly to the position of Quality Assurance Manager. This strengthens Argos technical and quality capability as Mr Skertchly has joined them from Marconi Space Systems where his work encompassed production and management aspects of hardware for the Exosat, Marecs, Meteosat and ERS 1 Satellite projects.

Technical Director Appointed at Mommers Print Service. From January 1 1990, Mr A. F. J. G. van der Kruijs B.Eng. has been appointed Technical Director of Mommers Print Service BV in the Netherlands. From 1981 onwards Mr van der Kruijs has been Quality Manager at this Dutch high‐tech printed circuit board manufacturing plant.

Environmental concerns over hazardous materials being placed in landfills have caused many countries to enact legislation to limit and/or eliminate the use of lead in electronic devices. As a result, the electronics manufacturing industry has undertaken efforts to comply with the legislation. Solder paste is typically used as the joining material between boards and components. The standard solder paste alloy has traditionally been a tin/lead eutectic. Lead‐free should, in theory, have the same functionality as the standard pastes to be utilized as a drop‐in replacement. Typically, solder paste is deposited on to a land pattern site by a stencil printer. In the manufacturing environment, speed and accuracy are desirable characteristics of the stencil printing operation. The purpose of this paper is to determine how fast a selection of lead‐free pastes can be successfully printed.

A representative sample of four lead‐free solder pastes containing different alloys was selected. A series of experiments at an increasing print speed was used to deposit these solder pastes on to printed circuit boards and the printed solder volumes were measured. The maximum print speed for each paste was observed and noted for future use.

Of the four alloys selected for experimentation, one emerged to have the most superior performance in terms of high‐speed printability. The speeds for each paste were observed and noted for future use.

Experimentation was performed in an electronics service provider's environment using equipment and materials that were normally used in production.

The parameters obtained can be used on the manufacturing floor assembling lead‐free products.

The results offer a suggestion (in the form of the parameters that can be utilized) as to what parameters to use in the stencil printing of lead‐free solder paste at high speeds.

The title of this report can be translated as ‘Let Singapore Flourish’. The Singapore Government is probably doing more than at least 90% of the other governments of the world, developed and developing nations combined, to ensure that the environment is respected, so that the little island‐state does indeed flourish. In a way, this is both ironical and necessary: both because there is comparatively little nature left on the island. What there is must be preserved, at all costs. Obviously, 26 million inhabitants concentrated mainly in Singapore City makes this an enormous field of reinforced concrete, albeit with some magnificent parks and other green spaces. Even some of these are oriented towards tourism and are more man‐made than natural. The island of Sentosa, a cable‐car or 10 minute ferry ride from the world's busiest harbour, is one of Singapore's playgrounds, but this is 85% touched by man's hands. Even the ‘Nature Walk’, purporting to be through primeval tropical rain forest, is a wide beaten track through mainly secondary jungle with a dearth of wild life. To the north of the city, there is some real rain forest—thankfully in a nature reserve—but the area is so small that one wonders whether it can be self‐sustaining in its natural state. To visit natural, uninhibited rain forest, a car ride across the causeway to the neighbouring state of Johore in Malaysia is probably necessary.

M & T Chemicals have announced the appointment of Mr David Smith as Director of PCB Systems and as a member of the company's Board of Management. Mr Smith, who was formerly Sales and Marketing Director of Lea Ronal (UK) Ltd, has had more than seventeen years experience in the printed circuit industry.

Originally a section of the Electronica Trade Fair, Productronia was first presented as a separate trade show for the manufacturing side of all kinds of electonic products in 1975. This year's event, the 6th International Trade Fair for Electronics Production, will once again offer the industry specialists a demonstration of the total product range in this important field: from base material for simple or complex components to testing equipment for devices ready for delivery or systems ready for operation.

Coventry‐based Shipley Europe have appointed George Allardyce to the newly‐created position of European technical manager. The appointment further strengthens Shipley's research, development and technical support team serving the European marketplace.

The flux residues on almost all soldered printed circuit boards are removed using the chlorofluorocarbon (CFC) 113. In just one year's time production of this solvent will almost certainly be curtailed, on a scale agreed internationally. This is a major issue that needs to be addressed urgently by the electronics assembly industry worldwide. This paper presents (i) the background that has led to the restrictions being placed on production and consumption of solvent 113, (ii) the international agreement and timetable for the implementation of the restrictions and (iii) the perceived opportunities that are available to the electronics assembly industry to meet this challenge.