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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 purpose of this paper is to investigate how impregnation with boron compounds affects the surface hardness of varnished wood materials.

Test samples were prepared from Scotch pine, Oriental spruce, and Uludag fir, which met the requirements of ASTM D 358.These samples were impregnated with boric acid (Ba) and borax (Bx) using a vacuum technique, according to ASTM D 1413 guidelines. After impregnation, surfaces were coated with cellulosic, synthetic, polyurethane, water‐based, acrylic, and acid‐hardening varnishes in accordance with ASTM D 3023 guidelines. Surface hardnesses of specimens after the varnishing process were determined, in accordance with ASTM D 4366 guidelines.

Surface hardness was greatest for samples of spruce treated with Ba and polyurethane varnish, and lowest for samples of Scotch pine treated with Bx and synthetic varnish. With regard to wood type, impregnation material, and varnish type, surface hardness was greatest for Oriental spruce impregnated with Ba and polyurethane varnish and lowest for Scotch pine impregnated with Ba and synthetic varnish. Thus, impregnation with boron compounds increased the surface hardness of the varnished wood.

A protective coating (such as varnish) has limited resistance to external effects and the lifetime of the coating will be determined by the type and severity of conditions to which it is exposed.

Types of varnishes, wood materials, and impregnation chemicals affect surface hardness and can influence the usefulness of wood materials, where surface hardness values are important.

The study results reported in the paper help address the lack of research in this field and should be informative, in particular, for manufacturers and consumers in the furniture and decoration sector.

The purpose of this paper is to determine the impacts of impregnation with Imersol Aqua to red colour tone (RCT) of some softwood materials and varnishes.

For this purpose, test samples prepared from Scots pine (Pinus sylvestris Lipsky), Oriental spruce (Picea orientalis Link) and Uludağ fir (Abies Bornmülleriana Mattf.), which met the requirements of ASTM D 358, were impregnated with Imersol Aqua by short‐term, medium‐term and long‐term immersion techniques in accordance with ASTM D 1413 and producer's definition. After impregnation, surfaces were coated by synthetic, acrylic, water‐based and polyurathane varnishes in accordance with ASTM D 3023 standards. RCT values of samples after varnishing process were determined in accordance with ASTM D 2244.

It was found that RCT was the highest in Scots pine, long‐term dipping and synthetic varnish, and the lowest in Uludağ fir, short‐term dipping and water‐borne varnish. Considering the interaction of wood type, period of impregnation and type of varnish, RCT was the highest in pine, short term of dipping and acrylic varnish and the lowest in Oriental spruce, short term of dipping and synthetic varnish. So, impregnation process, impregnation period and varnishes applied during tests showed increasing impact for RCT value of Scots pine, Oriental spruce and Uludağ fir woods. This result must be taken into care in manufacture of wooden furniture and construction elements where RCT is important.

The endurance of the protective coating (such as varnish) to external effects is limited and the lifetime of the coating is determined by the type and the severity of the effects to which it is exposed.

The impact of varnish type, wood material type and impregnation chemical on RCT can determine the usefulness of the massive wood materials where RCT values are important.

It is conjectured that especially for the manufacturers and consumers in the furniture, construction and decoration sector, the data obtained in this study will contribute to the making up of the deficiencies in the understanding of the subject.

The purpose of this paper is to determine the effect of Imersol Aqua impregnation of Scotch pine, Oriental spruce, and Uludağ fir on the surface adhesion strength of various types of varnishes. The finding obtained would benefit the manufacturers of building materials and furniture, where the surface adhesion strength of water‐based varnishes is a concern.

For this purpose, test samples were prepared from Scotch pine, Oriental spruce, and Uludağ fir woods that met the requirements of ASTM D 358. The samples were impregnated with Imersol Aqua using short‐, medium‐, and long‐term immersion techniques according to ASTM D 1413 and the manufacturer's instructions. After impregnation, surfaces were coated with synthetic, acrylic, polyurethane, and water‐based varnishes in accordance with ASTM D 3023 standards. After the varnishing process, the adhesion strength of the samples was determined in accordance with ASTM D 4541.

It was also found that among the wood samples, the adhesion strength was highest in Scotch pine and lowest in Uludağ fir. The synthetic varnish produced the highest adhesion strength, whereas polyurethane and acrylic varnishes had the lowest adhesion strength. The adhesion strength was highest after medium‐term immersion and lowest after long‐term dipping. The highest adhesion strength (4.299 MPa) was produced by a combination of Scotch pine, medium‐duration immersion, and the use of a wood‐based varnish. The lowest adhesion strength (2.090 MPa) resulted from the combination of Uludağ fir, long‐term immersion, and a water‐based varnish.

Impregnating woods using materials with appropriate water repellent, biotic, and abiotic effects before the application of varnishes and paints is important for long‐term protection against photochemical degradation, dimensional changes, biological factors, and fire.

The effect of a varnish on surface adhesion strength can determine the usefulness of the varnish.

Improving surface adhesion of some varnishes via medium‐term impregnation with Imersol Aqua impregnation should be used on Scotch pine, Oriental spruce, and Uludağ fir woods which could be used in the manufacturing of building materials and furniture, where the surface adhesion strength of water‐based varnishes is a concern.

Insulating varnishes are widely used for coating of armatures/coils of electric motors, transformers and also for finishing electrical components. Natural resin shellac finds considerable use in the manufacture of insulating varnishes. Improved dielectric properties have been obtained for varnishes prepared from shellac modified with synthetic resins, drying oils etc. The present article provides information about the researchers so far carried out on both the air‐drying and baking type of insulating varnishes based on shellac.

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.

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

Copolymer resins of peanut skin tannin extract, aldehydes and cashew nut shell liquid were prepared. The resins were blended with bitumen and used in formulating oleoresinous wood varnishes. The film properties of the varnishes were determined and the results showed that the gloss and scratch hardness of the films increased with increase in the quantity of cashew nut shell liquid/tannin‐aldehyde resins incorporated. The results also showed that the resins improved the chemical resistance of the varnish films. Varnish compositions containing 50:50 of bitumen and the resins gave films with satisfactory physical and chemical properties. The study showed that it is possible to formulate excellent oleoresinous wood varnishes using blends of bitumen and cashew nut shell liquid/tannin‐aldehyde resins.

The basic reasons for use of an overprint varnish are generally to afford protection to the inks and/or substrate and to promote gloss. The types of coating available can be summarised as follows in approximately an order of increasing gloss level.

Soybean oil was epoxidized in situ under established conditions. The produced epoxidized soybean oil was subjected to a sulfur containing compound of the formula (5‐phenyl‐1,3,4‐oxadiazole‐2‐(3H)‐thiones) and four of its derivatives (p‐chloro‐, p‐iodo‐, p‐methyl‐ and p‐methoxy‐) in sealed ampoules under inert atmosphere at 180‐2308C (according to the melting point of each sulfur compound). The produced adducts were added to three varnishes based on alkyd resin, chlorinated rubber and a vinyl chloride copolymer to evaluate them as corrosion inhibitors for steel surfaces. It was found that these adducts can act as good corrosion inhibitors and their efficiencies depend principally on the substituted functional group.