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Solvents, as the name implies, may be considered as the inert components of chemical reactions, purification, or cleaning processes, emerging chemically unchanged but contaminated with dissolved impurities and unsuitable for re‐use without subjection to a recovery process.

Looks at the increasing pressure from both environmental and health and safety aspects to overcome the problems associated with solvent‐based adhesives and comply with current and proposed legislation. Discusses the four basic solutions of using solvent containment, safe and environmentally‐friendly solvents, high solids systems and solvent‐free adhesives. Concludes that the long‐term option is solvent‐free systems such as water based, hot‐melt and liquid reactive adhesives, but substantial advances in technology are required if they are to make major inroads in the solvent‐based adhesive market.

CFCs and HCFCs have been used extensively in bulk cleaning of computer boards and are included in well established branch of chemistry. Due to the removal of one such CFC (CFC‐113) and the recent discontinuation of HCFC‐141b by the year 1996, there has been a push for the generation of new replacement solvents for these products. One of the new additions includes one product with an isomeric blend of two ingredients in the base formula. This isomeric mixture consists of 1,3‐dichloro‐1,1,2,2,3‐pentafluoropropane and 3,3‐dichloro‐1,1,1,2,2‐pentafluoropropane. Both isomers are under the trade name AK‐225. Recently, Tech Spray, Inc., were chosen as an authorised distributor for AK‐225. Current research has proven that AK‐225 can be used as an adequate replacement for the above solvents. Originally designed as a drop‐in replacement for CFC‐113, AK‐225 has also been proven effective as a replacement for HCFC‐141b in many tests performed. Alcohol blends with these solvents have been previously proven to have the ability to increase cleaning efficiency of the base solvent. One disadvantage of this is that, when large amounts of alcohols are added, the product becomes flammable. Tech Spray, Inc., have been able to prove that a wide range of azeotropes can be formed with even larger amounts of alcohols than were used previously in current CFC and HCFC blends and still remain non‐flammable. With existing properties, the AK‐225 azeotropes demonstrate broad defluxing abilities, and are also able to replace a wide range of solvents. AK‐225 can be used as a drop‐in replacement in current systems practising vapour degreasing, bulk in‐line use, and ultrasonic cleaning. As can be concluded from the test data, where used as a replacement for such solvents as mentioned above, AK‐225 and its blends can prove effective for drop‐in replacement. A major concern in the electronics industry today, due to the phase‐out of chlorofluorocarbon (CFC)‐113, and the recent discussion of the phase‐out of 1,1‐dichloro‐1‐fluoroethane (HCFC‐141b), is to find a new replacement exhibiting similar properties. The product must not only match but should also excel in solvent properties to reach the demands placed upon it by the electronics cleaning and manufacturing industry.

In August 1987, the EPA held a conference in Washington DC with consultants and users from the electronics industry to determine the feasibility of practical cleaning alternatives to reduce emissions of chlorofluorocarbon solvents which are considered to be a major contributor to the ozone problem in the stratosphere the world over. This paper presents a short resume of these goals and how they will affect cleaning in the electronics industry. Electronic design and packaging are the first steps in the soldering and cleaning processes. Selection of components compatible with alternative cleaning methods as well as process changes to permit low solids fluxes in some cases where cleaning can be eliminated will be discussed. ‘High containment’ in‐line solvent cleaning systems which reduce emissions are likely to become the new standard for the industry. Machines will become longer in order to include internal drying stages, instead of allowing a board with residual solvent trapped under components to evaporate after it leaves the machine prior to electronic test. Alternative solvents will become available. Designers of components and assemblies will respecify their designs to permit water cleaning, even for surface mount assemblies.

SOLVENT DEWAXING OF LUBRICATING oils found its first commercial application in 1927 when Indian Refining Company started its original acetone‐benzene dewaxing operation. Since that time, solvent dewaxing has wholly superseded the classical cold pressing methods in new installations. Of 171,165 bbls/doz. lube oil produced in the United States in 1951, some 60% was of the solvent extraction type and 40% of the older conventional type. By 1954, solvent extraction's share had risen to an estimated 75% of all dewaxing operations.

This paper aims to discuss the successful 3D printing of styrene–ethylene–butylene–styrene (SEBS) block copolymers using solvent-cast 3D printing (SC-3DP) technique.

Three different Kraton grade SEBS block copolymers were used to prepare viscous polymer solutions (ink) in three different solvents, namely, toluene, cyclopentane and tetrahydrofuran. Hansen solubility parameters (HSPs) were taken into account to understand the solvent–polymer interactions. Ultraviolet–visible spectroscopy was used to analyze transmittance behavior of different inks. Printability of ink samples was compared in terms of shape retention capability, solvent evaporation and shear viscosity. Dimensional deviations in 3D-printed parts were evaluated in terms of percentage shrinkage. Surface morphology of 3D-printed parts was investigated by scanning electron microscope. In addition, mechanical properties and rheology of the SC-3D-printed SEBS samples were also investigated.

HSP analysis revealed toluene to be the most suitable solvent for SC-3DP. Cyclopentane showed a strong preferential solubility toward the ethylene–butylene block. Microscopic surface cracks were present on tetrahydrofuran ink-based 3D-printed samples. SC-3D-printed samples exhibited high elongation at break (up to 2,200%) and low tension set (up to 9%).

SC-3DP proves to be an effective fabrication route for complex SEBS parts overcoming the challenges associated with fused deposition modeling.

To the best of authors’ knowledge, this is the first report investigating the effect of different solvents on physicomechanical properties of SC-3D-printed SEBS block copolymer samples.

The research aimed to identify ‘(1) current volatile solvent use practices, (2) health beliefs and perceived effects of volatile solvent use, (3) social dynamics of volatile solvent use, (4) significance of reputation, and (5) barriers to volatile solvent use intervention’ in a sample of Irish adolescents (Carroll et al, 1998, p1; Anderson & Loomis, 2003). Semi‐structured interviews were conducted with 20 adolescents who reported inhaling volatile solvents, during the course of doctoral research (n=1,400) investigating substance misuse among adolescents aged 12 to 18 years in Ireland. Their average age was 13.2 years, and they used a range of substances. Solvent users were found to be most commonly congregated in small peer and sibling groups and one young male also reported using alone. These young people indicated their average age of initiation of inhalant use as 10.3 years and most did not use inhalants after the age of 13 years. This coincided with first‐time alcohol use, at an average age of 12.5 years and experimental use of cannabis in some. All reported some awareness of short‐term medical risks involved in solvent use, and most commented on negative effects, such as headaches, dizziness and vomiting. Teachers, probation and juvenile liaison officers, health promotion and drug education workers, youth workers, social workers, and parents should ‘familiarise themselves with the real world experiences of adolescent volatile solvent users’; in order to develop appropriate and timely drug education interventions (Carroll et al, 1998 p6).

Solvent Balance is the key to prevention of undesirable application and film properties when non‐complying solvents are replaced in formulations that do not conform to pollution control regulations. Nitropropane has been shown to be effective as aid to balance control, improved adhesion and pigment wetting.

Examines adhesives and in particular how water‐based hot melt and liquid‐reactive are proposed as viable alternatives to solvent‐based types, quite apart from the health and safety and environmental legislation involved.

The dispersity of graphene oxide (GO) has an important effect on the properties of epoxy resin (EP) composites. Many modification and dispersion methods require the use of inert solvents which do not participate in the modification reaction, although GO can be uniformly dispersed in water and alcohol solvents. Based on this requirement, several inert solvents were selected as dispersion solvents to find out the suitable inert solvent for GO dispersion into EP matrix.

Several inert solvents with different solubility parameters were selected as dispersion solvents to prepare GO/EP composite. The microstructure, mechanical properties, insulation properties, dielectric properties and thermal property of the composite were characterized, which was due to find suitable inert solvent for GO dispersion into EP matrix.

The dispersity of N, N-dimethylformamide (DMF) was the best stable suspension state when it was used as solvent instead of occurring sedimentation and agglomeration. Moreover, DMF was further confirmed as a suitable inert solvent for the dispersion of GO into EP according to the mechanical properties, insulation properties and thermal conductivity characterization.

The dispersion of GO in solvents has already been researched, but the traditional solvents, such as alcohols and water, has shown their limitations with the increase of modification methods, which were not suitable for the modification environment such as cyanate graft modification. Therefore, it was very important to choose a kind of inert solvent for dissolving EP matrix and dispersing GO better.

Several inert solvents were used to disperse GO into EP, and the influence of different dispersing solvents on the adhesive was discussed through the analysis of the mechanical properties, insulation properties and thermal conductivity, which was due to explore the inert solvent suitable for GO dispersion.