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The surface characteristics of wood such as surface roughness, surface free energy (SFE) and wettability are important properties influencing further manufacturing processes such as gluing and coating. The purpose of this study is to determine the influence of surface roughness of ten tropical woods on their SFE, wettability and bonding quality for water-based acrylic and solvent-based alkyd varnishes.

The woods tested in this study were fast-growing teak, afrika, sungkai, mindi, merbau, durian, lamtoro, pulai, acacia and kempas. Wood surfaces were prepared in unsanded and sanded using an abrasive paper of 120 grits. SFE values were calculated based on the Rabel method. Wettability values were measured based on the contact angle between varnish liquids and wood surfaces using the sessile drop method, and the S/G model was used to evaluate the wettability of the varnishes on the woods surface. The bonding quality of the varnishes was measured using a cross-cut test based on the ASTM 3359-02 standard.

The results show that unsanded kempas wood had the roughest surface with a Ra value of 16.24 µm, whereas sanded lamtoro wood has the smoothest surface with a Ra value of 6.86 µm. The unsanded afrika wood had the highest SFE value of 53.61 mJ/m², whereas sanded fast-growing teak had the lowest SFE value of 36.17 mJ/m². Sanded merbau woods had the lowest K value of 0.022 for the water-based acrylic varnish, whereas unsanded afrika wood had the highest K value of 9.253 for the alkyd varnish. Afrika wood with the highest K values (highest wettability) for both acrylic and alkyd varnishes produced the highest bonding quality (grade 4-5). Compared to the water-based acrylic varnish, the solvent-based alkyd varnish was more wettable and generated better bonding quality.

Improving the quality of fast-growing wood from plantation by painting could be considered to increase their use for higher value wood products.

Compared to water-based acrylic varnish, solvent-based alkyd varnish was more wettable and generated better bonding quality.

The originality of this research is to evaluate the values of surface free energy. SFE could be used to quantitatively determined the wettability of paints liquid in the surface of wood

The surface characteristics of thermally and chemically modified wood, such as surface roughness, surface free energy (SFE) and wettability, are important properties that influence further manufacturing processes such as gluing and coating. The aim of this paper was to determine the influence of the surface roughness of thermally and chemically modified teak wood on their SFE, wettability and bonding quality for water-based acrylic and solvent-based alkyd varnishes. In addition, durability against subterranean termites in the field of these modified teak woods was also investigated to give a valuable information for their further application.

The woods tested in this study were fast-growing teak woods that were prepared in untreated and treated with furfuryl alcohol (FA), glycerol maleic anhydride (GMA) and thermal. SFE values were calculated using the Rabel method. The wettability values were measured based on the contact angle between varnish liquids and wood surfaces using the sessile drop method, and the Shi and Gardner model model was used to evaluate the wettability of the varnishes on the wood surface. The bonding quality of the varnishes was measured using a cross-cut test based on ASTM 3359-17 standard. In addition, durability against subterranean termites in the field of these modified teak woods was also investigated according to ASTM D 1758-06.

The results showed that furfurylated and GMA-thermal 220°C improved the durability of teak wood against termites. The furfurylated teak wood had the roughest surface with an arithmetic average roughness (Ra) value of 15.65 µm before aging and 27.11 µm after aging. The GMA-thermal 220°C treated teak wood was the smoothest surface with Ra value of 6.44 µm before aging and 13.75 µm after aging. Untreated teak wood had the highest SFE value of 46.90 and 57.37 mJ/m² before and after aging, respectively. The K values of untreated and treated teak wood increased owing to the aging treatment. The K values for the water-based acrylic varnish were lower than that of the solvent-based alkyd varnish. The untreated teak wood with the highest SFE produced the highest bonding quality (grades 4–5) for both acrylic and alkyd varnishes. The solvent-based alkyd varnish was more wettable and generated better bonding quality than the water-based acrylic varnish.

The originality of this research work is that it provides evaluation values of the durability and SFE. The SFE value can be used to quantitatively determine the wettability of paint liquids on the surface of wood and its varnish bonding quality.

Defines what varnish is, and traces its history. Outlines the various types of varnish and their main uses – alkyds, cellulose, melamine, epoxy, polyurethanes, phenolic, thermoplastic, and natural varnishes. Reviews 15 properties and terminologies associated with varnishes. Supplies two brief examples of proper use of varnish. Concludes with ten ′general rules′ of varnishing.

The paint industry in Western Europe is responsible for a solvent emission of several hundred thousand tonnes. The situation for the Eastern Europe is still not clear, but will certainly be worse than the West. Options for reducing solvent emission include the use of powder coating, UV and EB cured coatings, high solids and waterborne coatings. DSM Resins is able to produce alkyd emulsions for use in solvent‐free paints for decorative applications and maintenance systems. This paper is a further acquaintance with alkyd emulsions and there is a comparison between alkyd emulsions and acrylic dispersions.

The number of articles on solvent‐based acrylic resins in the paint industry has decreased in the past two years. It is not entirely clear why this is, since acrylic resins serve a key function in the industrial coatings segment of the paint industry, because of their outstanding weathering performance. The fact that they are available in both thermoset and thermoplastic forms makes them highly versatile. Structurally they are capable of wide variation, as indicated by an article by Ailhaud [Peintures, Pigments, Vernis, 47, March (1971) p. 170] who reports on the properties of block copolymers based on a variety of different alkyl methacrylates.

Alkyds are the work horse of paint industry. In order to obtain desired film properties, alkyd resins are frequently modified by other resins and polymers either by physically blending them or chemically incorporating them. Some of the recent physical modifications of alkyds have been described in this first part of the article. The chemical modifications will be described in the second part.

Some of the properties of paints based on alkyd emulsion are discussed and they are divided into four categories. Colloidal stability of water based paints is predominantly governed by osmotic and electrostatic repulsion of both the binder and the pigment particles. The rheological behaviour of paints based on binder dispersions should be optimised by using thickeners with the proper mix of hydrophilic and hydrophobic polymeric segments. Stability of drying properties of alkyd emulsion paints upon storage can be strongly improved by preventing the use of ketoximes as anti‐skinning agents and by selecting the proper driers. Properties of the dried paints depend strongly on the process of film formation. The protective and aesthetical quality of films based on binder dispersions is governed by the key parameters of the resin that is within the droplets; viscosity, miscibility and the ability of the binder to undergo crosslinking. To obtain the total package of desired properties of water based paints it is necessary that all of the paint components are adjusted to each other. This can only be done if the companies that develop and market the raw materials work closely together. The use of fundamental knowledge in such co‐makerships results in better and faster developments.

This study aims to propose a solution to decrease the environmental pollution caused by alkyd resins that harm the environment during their production and use.

A commercially produced polish formulation was used in the study. To reduce the use of this formulation in finishing polish, a water-saturated transparent solution of hydroxyethyl cellulose was used as a transparent filling material.

The use of hydroxyethyl cellulose at its optimum concentration in finishing polish only reduced the gloss by 0.027 per cent. The amount of alkyd was reduced by 24 per cent in weight.

The literature contained highly limited information on this subject. No transparent filling material was found. Thus, no comparison can be made with other studies.

The results obtained from this study can help manufacturers in the polish industry to produce varnish in a more cost-effective and eco-friendly way.

Considerable amount of volatile organic compounds released into the atmosphere as a result of the use of solvent-based dye/varnishes in the woodworking industry alone proves the importance of water-based systems. The results of this study indicate both economic and environmental gain.

In order to obtain desired film properties, alkyd resins are frequently modified by other resins and polymers either by physically blending them or chemically incorporating them. Some of the recent physical modifications of alkyd have already been described in the first part of the article. In this second part, the different types of resins and polymers used for the chemical modifications of alkyd resin are reviewed. A critical discussion on generally recognised advantages and disadvantages of the resultant coating from each modifier is described. Their use in surface coating industry are enumerated. Types of modifier to be used for improving a particular property in the coating are also suggested.

Gelation that can occur when copper or aluminium bronze powder is permitted to stand in nitrocellulose lacquer can be prevented by the addition of below one percent of lauric acid. Butyl acetyl ricinoleate will impart highgloss, plasticity, pliability to nitro‐cellulose lacquers and impart permanence, and improves the ageing properties and low temperature flexibility to the product. Acrylic coatings of improved gloss and pattern control have been provided by the addition of methyl hydroxystearate. When barium α‐sulphostearate is added to interior or exterior paints it can produce films of improved hardness. Methyl linoleate can be employed to retard the hardening of Japanese film lacquer. Compositions with good heat stability and good thixotropic properties and which are suitable for use as a base for paints have been evolved by reacting hydrogenated castor oil with toluene di‐isocyanate and emulsifiable and polyethylene wax. The use of aluminium stearate in paints at elevated temperatures can result in films of high opacity, good build, sag resistance, heavy pigmented tolerance and good sealing properties. Myristic acid‐based alkyd aryl ketones have been utilised to impart lustre to wooden surfaces, and stearic acid terminated polyamide/polyimide for coatings for electrical insulators of magnetic wire have been applied to give improved lustre. Diethylene glycol esters of dilinoleic acid can be used to produce non‐drip paints, as can ethylene diamine bis hydroxystearate, and glyceryl trihydroxystearate. Hydrogenated castor oil is useable in the making of thixotropic agents applicable to paints have been prepared from the material, plus oligomers of hydroxystearic acid/ethylenediamine/sebacic acid polymers. Ethyl linoleate and ethyl linoleate have been used as penetrants in anti‐corrosive paints based upon alkyd resins. Aluminium stearate can prevent excess penetration by paints of surfaces. Bis (hydroxymethyl) propanediol oleate has found use in alkyd resins derivative coatings with butylated melamine resins‐hardening materials to give pinhole resistant coatings. Butyl stearate is a good low temperature plasticiser for paints. Butyl acetyl ricinoleate imparts good plate release and cold crack resistance to leather lacquers, and provides good handle and excellent low temperature flexibility to coated fabrics on thick unsupported sheetings.