1. Introduction

This report covers an overview of the results achieved within the Kamille II project. The project has had the aim of comparing electronics joining technologies based on conductive adhesives and traditional SnPb-solders, respectively. The report describes the environmental aspects of introducing conductive adhesives in electronics manufacture compared with solder. It also contains a technical assessment of 13 adhesive variants by means of laboratory surveys and industrial cases.

The Kamille project aims to describe the environmental aspects of the electronics industry’s transition from traditional lead-rich solder to lead-free adhesives for bonding components to printed circuit boards. The project is funded by a grant from the Danish Environmental Protection Agency.

The Kamille II project has been reported in the following working reports:

-        Life Cycle Assessment of electrically conductive adhesive versus   traditional tin/lead solder, Christensen F M

-        Silver resource aspects of substituting tin/lead solders with electrically conductive adhesives, Christensen F M, Jensen A B

-        Occupational health aspects of adhesive and solder technology, Christensen F M, Jaroszewski M, Syska J, Cohr K H

-       Toxicological aspects of electrically conductive adhesives as compared to tin/lead soldering systems, Cohr K H, Christensen F M

-       Recycling analysis of electrical and electronic products assembled with tin/lead solder and electrically conductive adhesives, respectively, Christensen F M

-      Comparative testing of electrical conductive adhesives on various substrate platings with different component finishes, Jørgensen T

-       Electronic prototype assembly with electrical conductive adhesives, Jørgensen T

Party to the project are Technoconsult (project leader), Danish Toxicology Centre, DELTA Danish Electronics, Light and Acoustics, Danfoss, Grundfos, Bent Hede Elektronik, ElektroMiljø and MEKOPRINT.

The electronics and electrical industries are facing increasing pressure from legislation to remove lead from its products. This is because of the hazards to health during manufacture of the materials and environmental damage caused by their end of life disposal. In order to address adequately the environmental problems associated with the current methods for the treatment and disposal of Waste from Electrical and Electronic Equipment (WEEE), it is considered to introduce measures at Community level that aim, firstly, at the prevention of WEEE, secondly at the reuse, recycling and other forms of such wastes and, thirdly, at minimising the risks and impacts to the environment from the treatment and disposal of WEEE. It is also the aim of this initiative to contribute to the harmonisation of national measures on the management of WEEE in order to ensure the functioning of the internal market. These measures are being proposed in two separate Directives. The first – the draft Directive on WEEE – deals with the management of waste and is based on Article 175 of the Treaty. The second, which seeks to harmonise national measures on the restriction of the use of certain hazardous substances in electrical and electronic equipment, is based on Article 95 of the Treaty.

If the European Commission ratifies the legislation, there will be a major impact on all industries using electronic and electrical components. For producers using/producing solder systems, electronic components and PCB’s, this legislation is likely to result in the following changes in their production/assembly systems:

	Switch from the traditional tin/lead solder to a lead free solder or
	Switch from the traditional tin/lead solder to conductive adhesives
	Switch from tin/lead plating on PCBs to a lead free plating
	Switch from tin/lead plated comp onents to lead free plated components
	Modification of the soldering process (temperature, fluxes, etc.)

The present report presents the summary results of the Kamille II project. More detailed project results can be found in the project working reports. This report considers the results of this project and includes the following subjects:

	Toxicological aspects
	Life cycle assessment
	Occupational health aspects
	Silver resource aspects
	Recycling analysis
	Test of 13 conductive adhesives by means of laboratory studies
	4 industrial case studies

A survey of solder consumption was carried out by means of interviews with the leading suppliers of solder on the Danish market. Interviews were also conducted with a number of major Danish manufacturers of electronic equipment with a view to mapping out the quantities of particular types of solder used for particular processes.

The study has formed the basis for an assessment of the types and quantities of solder used in the following processes: surface mounting, through-hole mounting, Hot Air Solder Levelling, component termination, automated mounting and manual reparation

Conductive adhesives can replace solder paste in some reflow soldering applications and will also make it possible to eliminate the use of solder for component terminals. The SnPb pre-tinning process, nowadays often employed for the surface treatment of printed circuit boards, can also be replaced by the use of e.g. flash gold. In addition, conductive adhesives will probably be able to replace parts of the lead currently used for wave soldering of through-hole mounted components.

The Danish electronics industry’s consumption of solders is estimated to be approximately 130 tonnes per year, with 4 tonnes being used in reflow soldering, 80 tonnes in wave soldering, 16 tonnes in surface treatment and 30 tonnes in manual mounting and repair using solder wire. On top of this are the 3 tonnes contained in terminals on bought-in components, see [1].