Impregnation of Preservative and Fire Retardants into Japanese Cedar Lumber by Passive Impregnation

Abstract

aCopper azole type B (CAz-B) preservative and polyphosphatic carbamate (PPC) fire retardants were impregnated in succession into green (97% MC) and kiln-dried (18% MC) Japanese cedar (Cryptomeria japonica (L.f.) D.Don) lumber by the passive impregnation method to prolong the period of lumber use by increasing its resistance to fire and biological degradation. Lumber was dried with a kiln or by air-drying. Total chemical retention, penetration, leaching, decay resistance (JIS K 1571), and fire retardancy (ISO 834-1 standard, 20 minutes) tests were performed according to the mentioned standards. Preservative retention was higher in the green lumber (4.97 kg/m 3 ) compared with the kiln-dried (4.88 kg/m 3 ) lumber. However, fire retardant retention was similar for both lumber types (107 and 111 kg/m 3 ). Leaching was higher in kiln-dried lumber (21.8%) compared to air-dried lumber (14.4%), although there were no significant differences in the decay resistance test between these two lumber types. The fire performance of both lumber types was similar in the fire resistance test. Therefore, the passive impregnation method can be used effectively for impregnation of both preservatives and fire retardants into wood.

A review of flame protection of wooden material and future potential with nano additives

“…the anatomy of wood and the size of openings in the wood structure, which allows chemicals to penetrate the wood. Wood incising (Islam et al 2013, Civardi et al 2016 or pretreatment with steam (Ishikawa et al 2005, Islam et al 2013) can improve the penetration and retention of chemicals.…”

Effect of using laser incising treatment and fire-retardant coating on Larix kaempferi wood to improve fire retardant performance

“…Certain properties in the Japanese larch, a common building material among conifers in Korea, prevent injection of chemicals by general pressurization or depressurization treatment regardless of moisture content (Choi et al 2011). Laser incising is being used on wood species that are difficult to inject, such as Japanese larch, to improve the penetration of chemicals (Islam et al 2008(Islam et al , 2013.…”

Fire Properties of Pinus densiflora Utilizing Fire-retardant Chemicals based on Borated and Phosphorus (I) – Combustion Characteristics

“…Over the past few decades, many studies have focused on fire retardant-treated woods (FRTWs) because wood is flammable due to its main components (Angeler et al 2004;Pabeliña et al 2012;Islam et al 2013;Lowden and Hull 2013). To improve the fire retardancy properties of wood, fire retardant chemicals, such as boron, boric acid, phosphorous, phosphates, and nitrogen, have been used to form a char on the surface of treated materials (Altun et al 2010;Branca and Blasi 2011;Lowden and Hull 2013).…”