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Article
Publication date: 5 July 2011

M. Atar, H. Keskin, S. Korkut and D.S. Korkut

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

157

Abstract

Purpose

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

Design/methodology/approach

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.

Findings

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.

Research limitations/implications

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.

Practical implications

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.

Originality/value

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.

Details

Pigment & Resin Technology, vol. 40 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 13 September 2011

Haken Keskin and Musa Atar

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.

127

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Research limitations/implications

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.

Practical implications

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.

Originality/value

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.

Details

Pigment & Resin Technology, vol. 40 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 24 May 2011

Hakan Keskin, Musa Atar, Süleyman Korkut and Derya Sevim Korkut

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…

191

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Research limitations/implications

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.

Practical implications

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

Originality/value

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.

Details

Pigment & Resin Technology, vol. 40 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 January 1993

C. Paul Sharma, K.L. Vadera and R.P. Agarwal

In the past, solvents containing impregnation systems were in vogue, e.g. phenoloic‐alkyd, isophthalic polyester, silicone, etc. for electrical machines. The disadvantages of…

Abstract

In the past, solvents containing impregnation systems were in vogue, e.g. phenoloic‐alkyd, isophthalic polyester, silicone, etc. for electrical machines. The disadvantages of solvent borne impregnants are a higher dissipation factor (at elevated temperatures) and water absorption, etc., due to the presence of air voids formed during the curing process. The phenomenon has been controlled with the present day use of solvent/ess systems, e.g. polyester, polyesterimide, epoxy and silicone resins. Solvent/ess polyester resins are now indigenously available along with their additives such as: inhibitor, catalyst and reactive diluent, etc. Modern methods of impregnation for electrical machines in BHEL include: (a) Dip impregnation by rotational method (b) V P I process The methods include storing the catalysed resin in cool storage, warming for impregnation, and final impregnation under vacuum and pressure, and curing in an oven. A monitoring system has also been standardised for the impregnation resin to keep its viscosity and gelling time within the specified tolerances by the addition of an appropriate amount of inhibitor and reactive diluent. Proper monitoring keeps the tank life of the system indefinitely long and its properties within limits.

Details

Pigment & Resin Technology, vol. 22 no. 1
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 1 April 2005

N.A. Fadl and A.H. Basta

To investigate the effects of acetylation process as a chemical treatment method to improve the dimensional stability of wood, or as a pre‐treatment step to enhance the…

Abstract

Purpose

To investigate the effects of acetylation process as a chemical treatment method to improve the dimensional stability of wood, or as a pre‐treatment step to enhance the dimensional stability of wood by impregnates.

Design/methodology/approach

Esterification of two species of wood were carried out by vapour and liquid phase acetylation processes. With the vapour phase acetylation process, wood with different acetyl contents were obtained by changing the length of time of treatment. With the liquid phase acetylation, different acetyl content were obtained by changing the acetylating mixture or by activating wood with acetic acid for different periods of time and at different temperatures prior to the acetylation processes. The acetyl content and the conditions of impregnation improving the dimensional stability were modelled and optimised. The success of acetylation process for improving the affinity of wood towards the impregnation was also demonstrated.

Findings

Vapour phase acetylation process was preferable over liquid phase acetylation for improving both water resistance and dimensional stability of wood species examined. Liquid acetylating of wood, as a pre‐treatment step enhanced the effect of impregnates, especially the linseed oil to improve relevant wood properties. The greater improvement was obtained at 3 h impregnation time and 190°C curing temperature for 1 h.

Research limitations/implications

Despite the success in improving the affinity of wood species to novolac by pre‐acetylation, increasing the curing time and curing temperature led to deterioration of the water resistance and dimensional stability.

Practical implications

Pre‐acetylation of the wood provided a practical solution to rendering the natural wood greater water resistance property using commercial impregnates.

Originality/value

The method for acetylation of wood prior to impregnation was novel and could be used for inhibiting wood against moisture absorption during storage.

Details

Pigment & Resin Technology, vol. 34 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 May 1996

Altaf H. Basta, Naim A. Fadl and Usama I. Gabra

Studies the treatment of wood‐processing waste using different impregnants as a tool for improving its water‐resistance properties, in order to achieve a reduction in the damage…

Abstract

Studies the treatment of wood‐processing waste using different impregnants as a tool for improving its water‐resistance properties, in order to achieve a reduction in the damage to building elements prepared from the treated wood waste when exposed to weather of relatively high moisture content. Applies different variables such as type of impregnant (synthetic resins or oils), concentration of impregnant, time of impregnation and thermal treatment. Obtains results which show that, generally, using a different concentration of synthetic resins (UF and novolac), or dry oils (motor oil and linseed oil) improved the water‐resistance property of wood waste, and that thermal treatment increases the improvement percentage as a result of impregnation. Also indicates that the optimum improvement in water resistance is attained when using 50 per cent linseed oil as the impregnant for an impregnation time of ten minutes, followed by hardening for three hours at 120°C.

Details

Pigment & Resin Technology, vol. 25 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 March 2006

Geoffrey Mark Caldwell

The homosexual community has undoubtedly been assuming senior managerial positions of authority within government for generations, Clinard (1968). However, homosexuals are now…

Abstract

The homosexual community has undoubtedly been assuming senior managerial positions of authority within government for generations, Clinard (1968). However, homosexuals are now moving more publicly, rather than surreptitiously into the echelons of managerial roles within the bureaucracy, (Clinard, 1968, Barker & Allen,, 1976, Wofford, 1993). This research suggests that this homosexual openness has in some cases created an environmental despotism where the homosexual managerial minority may openly and selectively discriminate towards their fraternal association and specifically against the heterosexual majority. Is there now the means, for homosexual managers to impose retribution for the chronicled persecution of homosexuals by heterosexuals? If so, could this retribution be leading to homosexual managers replicating the ideologies of the “old boys’ club” by creating their separatist “guys’ club”. Would this sex-oriented preference discrimination resemble a somewhat disturbing paradox: Discrimination defined by sex inclination and such discrimination which ironically was associated with the powerful heterosexual males, and which they mysteriously fought vigorously and actively against?

Details

International Journal of Organization Theory & Behavior, vol. 9 no. 1
Type: Research Article
ISSN: 1093-4537

Article
Publication date: 1 December 2005

Yanyun Zhao, Su‐il Park, Scott W. Leonard and M.G. Traber

This study aims to evaluate the use of vacuum impregnation (VI) for developing vitamin E fortified fresh‐cut apples (Fuji).

Abstract

Purpose

This study aims to evaluate the use of vacuum impregnation (VI) for developing vitamin E fortified fresh‐cut apples (Fuji).

Design/methodology/approach

A 20 per cent high fructose corn syrup (HFCS) or edible coating materials of 1 per cent hydroxypropyl methylcellulose (HPMC) and 1 per cent calcium caseinate (CC) were used to make VI solutions, and 0.4 per cent α‐tocopherol acetate, 7.5 per cent gluconal cal\tf="Pi3" \char"31 (GC) and 0.04 per cent zinc lactate (ZL) were incorporated into the VI solutions. Vitamin E content, color, and selected physicochemical properties of fortified fresh‐cut apples were analyzed.

Findings

Results showed that VI treatment with 20 per cent HFCS solution containing 0.4 per cent α‐tocopherol acetate increased vitamin E content up to 21.8 mg in 100 g of fresh‐cut apples, while 12.0 mg and 20.2 mg vitamin E were achieved when using 1 per cent HPMC or 1 per cent CC as VI solutions, respectively. Calcium and zinc content were also increased to 146.6 mg and 1.7 mg in 100 g of apples, respectively, when adding 7.5 per cent GC and 0.04 per cent ZL along with the vitamin E into the VI solutions. Use of HFCS, HPMC and CC as VI solutions resulted in different effects on the physiochemical properties of fresh‐cut apples. While HFCS is promising for vitamin E fortification and retention of natural apple color, HPMC and CC can be used to achieve similar vitamin E fortification with the least impact on the soluble solids and moisture contents of apples.

Originality/value

The study demonstrates that there is great potential for developing high quality, vitamin E and minerals fortified fresh‐cut apples using vacuum impregnation technology, thus further enhancing the health benefit of the apples.

Details

Nutrition & Food Science, vol. 35 no. 6
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 7 March 2016

Peixin Liang, Yulong Pei, Feng Chai and Shukang Cheng

For high torque-density permanent magnet synchronous in-wheel motor, service life and electromagnetic performance are related directly to winding temperature. The purpose of this…

Abstract

Purpose

For high torque-density permanent magnet synchronous in-wheel motor, service life and electromagnetic performance are related directly to winding temperature. The purpose of this paper is to investigate the equivalent stator slot model to calculate the temperature of winding accurately.

Design/methodology/approach

This paper analyzes the the law of heat flux transfer in slot, which points the main influence factors of equivalent stator slot model. Thermal network model is used to investigate the drawbacks of conventional equivalent model. Based on the law of heat transfer in stator slot, a new layered winding model is put forward. According to winding type and property of impregnations, detailed method and equivalent principle of the new model are presented. The accuracy of this new method has been verified experimentally.

Findings

An accurate equivalent stator slot model should be built according to the low of heat transfer. According to theory analysis, the drawbacks of conventional equivalent stator slot model are pointed: it cannot reflect the temperature gradient of winding; the maximum and the average temperature of winding are much higher than actual value. For the new layered model, equivalent principle is related to winding type and property of impregnations, which makes the new model widely used.

Originality/value

This paper presents a new layered model, and shows detailed method, which is more meaningful for designers. The new layered model takes winding type and property of impregnations into account, which makes the new model widely used. It is verified experimentally that layered model is applicable to not only steady-state temperature field but also transient temperature field.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 35 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 February 1979

A. Meozzi

The production process of the PDR 100 epoxy glass based laminate, as developed by Philips, Holland, produced laboratory results which, with appropriate modifications, were applied…

Abstract

The production process of the PDR 100 epoxy glass based laminate, as developed by Philips, Holland, produced laboratory results which, with appropriate modifications, were applied by MAS SpA to achieve successful production of a laminate with proven consistency of quality. Industrial tests were carried out on material of varying thickness. The preparation of the resin mix, which differed in composition from that used by the Philips pilot plant, is described in detail, followed by the impregnation process, with emphasis on the precautionary measures necessary. The processes of pressing and finishing of the laminates are discussed, the emphasis again being on the prevention of contamination. The presence of titanium dioxide in the epoxy resin is fully explained and details are given of two technological processes of impregnation. The paper concludes with a summary of the typical properties and characteristics of the PDR laminates.

Details

Circuit World, vol. 5 no. 3
Type: Research Article
ISSN: 0305-6120

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