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Changes in regulations aiming at reducing the impact that technologies such as coatings, adhesives, cleaners have on the environment is leading to large advances in these end‐use technologies. In achieving the required quality of the end product, and irrespective of whether this is in areas such as high solids paints or water‐based coatings, solvents keep on playing an important role. At the same time different requirements are set for the solvents employed. The changing role of solvents and the technological benefits solvents are bringing are discussed. It is shown that the computer programme BLENDPRO is an effective reformulation tool which assists in the efficient development of new formulations in these areas.

In Graz, Austria, the European Rotogravure Association (ERA) held a conference where several companies presented new developments in the printing industry including the latest developments in the field of water‐based ink systems. This paper discusses water‐based inks for gravure printing.

Polyurethane (PUR) foam parts are traditionally manufactured using metallic molds, an unsuitable approach for prototyping purposes. Thus, rapid tooling of disposable molds using fused filament fabrication (FFF) with polylactic acid (PLA) and glycol-modified polyethylene terephthalate (PETG) is proposed as an economical, simpler and faster solution compared to traditional metallic molds or three-dimensional (3D) printing with other difficult-to-print thermoplastics, which are prone to shrinkage and delamination (acrylonitrile butadiene styrene, polypropilene-PP) or high-cost due to both material and printing equipment expenses (PEEK, polyamides or polycarbonate-PC). The purpose of this study has been to evaluate the ease of release of PUR foam on these materials in combination with release agents to facilitate the mulding/demoulding process.

PETG, PLA and hardenable polylactic acid (PLA 3D870) have been evaluated as mold materials in combination with aqueous and solvent-based release agents within a full design of experiments by three consecutive molding/demolding cycles.

PLA 3D870 has shown the best demoldability. A mold expressly designed to manufacture a foam cushion has been printed and the prototyping has been successfully achieved. The demolding of the part has been easier using a solvent-based release agent, meanwhile the quality has been better when using a water-based one.

The combination of PLA 3D870 and FFF, along with solvent-free water-based release agents, presents a compelling low-cost and eco-friendly alternative to traditional metallic molds and other 3D printing thermoplastics. This innovative approach serves as a viable option for rapid tooling in PUR foam molding.

The trend towards a greater use of water as the solvent in flexographic and gravure printing inks has been influenced by a number of factors — the growing attention to environmental pollution problems, health and safety aspects, elimination of residual print odour in food packaging printing and conservation of organic solvents.

This paper aims to compare the aging behavior of water-based coatings and solvent-based coatings in sulfuric acid environments and to discuss the related mechanism.

A sulfuric acid solution with a concentration of 5 Wt.% was selected for immersion test at 23°C. The failure behavior of the coating was studied by combining the transformation rules of the macroscopic morphology and basic properties with the results of electrochemical impedance spectrum analysis.

The results showed that the surface smoothness of the water-based coating was lower than that of the solvent-based coating. The glossiness, thickness and hardness of the water-based coating exhibited more significant changes. The electrochemical test also indicated that the water-based coating was infiltrated by a large number of corrosive media, which may have induced corrosion under the coating. In contrast, the solvent-based coating showed good shielding properties, but the adhesion was seriously affected by the corrosive medium.

This work clarified the difference of failure behavior and mechanism between water-based coatings and solvent-based coatings in acidic environment and provided a theoretical basis for the selection and mechanism research of anticorrosive coatings.

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.

In recent years numerous pieces of environmental legislation have been introduced or will be introduced both in the UK and throughout Europe. The greatest environmental issue at the moment is the limitation of volatile organic compound (VOC) emissions. Water‐based coatings have been available for many years; their main application initially was for broad wall paints. More recently, water‐based coatings have come on the market for trim coatings. Although their performance for interior use is sufficient, but inferior to their solvent‐based alternatives, how do water‐based coatings for exterior wood perform? An alternative to water‐based technology is high solids. In a recent life cycle analysis (Ministry of the Environment in France) high solids alkyds have been shown to have low environmental impacts. In the study used for setting the criteria and thresholds for the European eco‐label for decorative paints and varnishes, a high solids alkyd developed by Cray Valley Ltd was put into the category having the lowest environmental impact together with water‐based paints. For the future of exterior coatings for wood, is the route to environmentally friendly coatings water‐based or solvent‐based technology?

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.

Highlights the work carried out by the author's company, Thortex, in developing water‐based and solvent‐free coating products. Briefly defines the benefits of water‐based coatings and lists some of their applications.