木材の寸法安定性,耐朽性および難燃性を改良する目的で,ホウ酸(H₃BO₃)とジイソシアン酸トリレン(TDI)を含浸し,105℃で加熱処理することによって複合化木材を得た。処理試験片は流水による溶脱処理後の重量減少は非常に少なく,高い耐溶脱性を示した。これはホウ酸が木材中でTDIと結合したためであり,FT-IRスペクトルから主な化学反応はホウ酸の水酸基とTDIの重合反応であると考えられる。得られたホウ酸-TDI複合化木材は細胞壁のバルキング効果によって高い寸法安定性を示した。腐朽試験において,ホウ酸-TDI複合化木材は溶脱処理後でも優れた耐朽性を示した。また,複合化木材はミクロバーナーおよび酸素指数による燃焼試験においても良好な難燃性を示した。

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親水性材料表面のはっ水化を目的に，エチレンのプラズマ重合処理を検討した。処理表面の湿潤性はグリセリン接触角によって評価し，エチレン堆積膜の厚さは，エリプソメトリーを用いて測定した。結果として，流速0.1L/minのエチレン気流下，12.75kVで5分間プラズマ処理すると，推定10.5nm厚さのはっ水性膜が堆積することが分かった。同様にして，平滑化木材表面のプラズマ処理を行い，コナラおよびダグラスファー表面のはっ水化に成功した。処理した木材は，10日間水中に浸漬してもはっ水生を維持していた。処理前後の差は肉眼では判断できなかった。

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WPC was produced from corona-pretreated wood and methyl methacrylate (MMA). To remove MMA homopolymer, WPC specimens were extracted with acetone. Dimensional stability of these WPC specimens was compared with that of WPC produced by an ordinary heat catalyzed method.
The degree of apparent grafting of MMA to wood (wall polymer content) increased with an increase in corona discharging time (0-120 minutes, 15kV). The wall polymer content of the WPC exceeded that of an ordinary WPC, and it reached the maximum of 80%.
Anti-swelling efficiency (ASE) and moisture excluding efficiency (MEE) of the WPC exceeded that of the ordinary WPC, and they reached the maximum of 50 and 55%, respectively. Relationship between ASE and wall polymer content was linear in both tests of moisture and water absorption. Furthermore, relationship between MEE and wall polymer content was linear. These relationships of ASE and MEE against wall polymer content were the same as those of the ordinary WPC.
From the results of wall polymer content and dimensional stability, the most suitable concentration of MMA-methanol solution for the impregnation into wood was found to be 80%.

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The distribution of silicic acid gel and boron compounds in wood-mineral composites made using the silicate-boron compound system was examined by electron probe X-ray microanalysis (EPMA). The fire resistance of the composites was also evaluated by applying both oxygen index and percent weight of residual char. The composites were produced by diffusion-penetrating the water glass-boron compound system (double treatment) and the colloidal silica solution system in the sapwood specimens of Sugi (Cryptomeria japonica). For comparison, the composites were also prepared by impregnating boron compounds only into the wood (single treatment).
In the single treatment, most of boron compounds in the composites was located in the cell walls as obvious from boron X-ray maps. However, boron compounds themselves were almost all leached out by the leaching procedure, showing no fixation of them in the composites. On the other hand, in the double treatment having the fixation of 5470% after leaching, silicic acid gel was located mostly in the cell lumina and it was very small in quantity in the cell walls as seen from silicon X-ray maps whereas boron compounds existed in the cell walls besides the lumina even after leaching.
In the colloidal silica solution system having the high fixation of 86-94%, most of silicic acid gel was deposited in the cell lumina as an insoluble solid body and it was also very little in the cell walls. In addition, the distribution of boric acid was clearly observed not only in the lumina but also in the walls even after leaching.
As a result of fire-resisting test, the oxygen index of the composites trended to increase with an increase in weight percent gain (WPG) and there was a high correlation between the two. The percent weight of residual char was highly correlated to WPG independently of leaching and it increased lineally with an increase in WPG. It may be possible that the percent weight of residual char becomes one way for estimating the fire resistance of the composites because of a high correlation with the oxygen index after leaching.

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親水性材料表面のはっ水性化を目的にエチレン大気圧プラズマ処理を行った。処理によってエチレンが重合し，セロハン表面がはっ水性化された。エチレンガスにアルゴン，窒素，二酸化炭素を混合することで堆積量は大きく増加したが，カルボニル基に由来する極性力成分も増加した。処理後のセロハン表面は糸状の堆積物が絡み合ったような構造であった。また，処理雰囲気によって堆積物の太さと絡み方が異なっていた。

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The presence and distribution particularly of boron compounds among inorganic substances are related greatly to the enhancement of performances such as decay, termite, and fire resistances in wood-mineral composites (WMCs). Regarding ashes obtained by removing an organic matter with heat-burning, the quantitative ratios of inorganic components like silicic acid, boron compounds, and others in composites made using various silicate solution system were investigated by means of the weighing method, X-ray fluorescence analysis, and ICP (inductivity coupled plasma) spectrometry. Also, the silicon concentration in leached solution from WMC specimens was determined by atomic absorption spectrometry. Further, we conducted the decay test to examine the relation between the presence of inorganic compounds and the performance enhancement. The WMCs were prepared by diffusion-penetrating the water glass-boron compound system (double treatment) and the colloidal silica solution system in the sapwood specimens of Sugi (Cryptomeria japonica) in addition to the new impregnating process of water glass-boron acid mixing solution (single treatment).
From the above analyses, the general tendency on the contents of silicic acid, sodium oxide, and boron became clear. There existed a considerable amount of sodium oxide in WMC specimens made with the water glass-boron compound system and the water glass-boric acid mixing solution. It decreased in quantity owing to exudation out of specimen by leaching procedure and hence the relative ratio of silicic acid increased greatly. Almost all of inorganic substances consisted of silicic acid in the colloidal silica solution system and it hardly leached out because of the tight fixation in the specimen. The content of boron could be determined by ICP spectrometry and it decreased considerably in quantity by leaching procedure. However, even a small amount of boron left proved to be very effective to the enhancement of decay resistance from the result of decay test.

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The applicability of colloidal silica for producing a wood-mineral composite by impregnation was investigated, and its properties such as dimensional stability and decay and fire resistances were evaluated.
The colloidal silica solution was prepared by mixing silicic acid anhydride (30.4%), boric acid, and chitosan with a low molecular weight (0.3%). Instead of boric acid, metal ions of Cu, Ag, or Ti (1000ppm) were added to the solution. The solution was diffusion-penetrated into the water-saturated specimens of Sugi (Cryptomeria japonica D. Don), followed by drying to solidify the colloidal silica for a combination. The formation of silicic acid gel in the composites made by using the colloidal silica solution system was proved to be mostly insoluble.
The composites showed an antiswelling efficiency with the greatest value of 23% due to the bulking effect despite being hygroscopic and a good reduction in water absorptivity. Also, the composites, particularly those by using the colloidal silica-boric acid system, were found to improve greatly the decay and fire resistances.
For practical use, the composites were manufactured with boards of yellow poplar (Liriodendron tulipifera L.) applying the colloidal silica-boric acid system. They showed the enhancement of bending strength and modulus of elasticity to some extent of apparent weight percent gains. The absorbed energy in impact bending became greater than that of the untreated wood.

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本研究では,スギ丸太を材温80℃,40時間で燻煙熱処理を行い,壁孔壁の破壊率を測定した。また熱処理後,市販の難燃剤で減圧注入処理し,重量増加率を求め,薬剤の浸透性を評価した。さらに,作製した難燃材の難燃性及び材質特性を評価した。燻煙熱処理により,破壊された壁孔壁の割合は,心,辺材ともに増加した。減圧注入処理による重量増加率は,燻煙熱処理心材において大幅に増加する傾向が認められた。燃焼試験後の重量残存率は,減圧注入時の減圧度の増加と共に増加した。また,曲げ強さについては,薬剤注入による大幅な変化は認められなかったが,曲げヤング率は,重量増加率の増加にともなって増加する傾向が認められた。

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ダイキン工業は，天然由来成分を使用した紙用非フッ素耐油剤「XP-8001」を開発した。
当社の紙用耐油剤「ユニダイン」は，“油を弾く”機能にこだわり，撥油性を有するフッ素材料による製品開発を行ってきた。今回，日々高まるサスティナビリティのご要望に応えるため，フッ素材料を含まない紙用耐油剤の開発に取り組んだ。非フッ素材料は，その材料特性から高撥水撥油性能を発現させることは困難であるが，表面張力の低いアルキル基の結晶性を高めることで，高温での耐油性を実現した。澱粉類の併用によって薄膜でも耐油性の発現が可能である。また，XP-8001は，紙が本来持っている特性である通気性や離解性を大きく損なうことなく，耐油性の付与が可能である。

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The mechanical properties such as bending strength, hardness, and abrasion resistance of wood-mineral composites were investigated, which were made by introducing inorganic substances into wood using the water glass (sodium silicate)-boron compound system. The heartwood of Sugi (Cryptomeria japonica D. Don) and five kinds of boron compounds were used for the production of the composites. The impregnated specimens were treated with a 5% acetic acid solution to minimize the influence of alkali in the water glass solution.
The weight percent gains (WPGs) in the composites varied from 20% to 65%, and the WPG values of 10-26% after the leaching procedure were obtained, demonstrating the formation of inorganic substances. The bending strength of the composites showed an increase of 6-25% in comparison with the untreated wood. The increase in the modulus of elasticity was also 16-41%, and it increased lineally with an increase in WPG. On the other hand, the strain at failure became lower than that of the untreated wood, and it had a tendency to reduce as the WPG increased.
The Brinell hardness in the cross section showed a marked increase of 50-150% compared with the untreated wood. Because of increasing lineally with an increase in WPG, the enhancement of hardness in the cross section seemed to be due to the filling effect of inorganic substances. On the contrary, the hardness in the radial and tangential sections showed a reduction, and it tended to reduce with an increase in WPG. The reduction of hardness was considered to be closely related to the bulking and the wood deterioration resulting from soaking in an alkaline solution in the wood surface layer.
The Taber type abrasion index in the radial and tangential sections tended to increase with an increase in WPG, showing the reduction of abrasion resistance. This reduction could be also explained by the influence of the bulking and the deterioration owing to alkali.

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Wood-mineral composed (WMC) veneers were manufactured with Japanese cedar (Sugi: Cryptomeria japonica) and Japanese oak (konara: Quercus serrata) using the colloidal silica-boric acid system for the purpose of enhancing the fire retardancy of veneers. The evaluation of fire retardancy was experimented by two burning tests with oxygen index (OI) and microburner methods. In addition, the residual char produced after the OI-burning test was observed by electron probe X-ray microanalysis (EPMA).
Weight percent gains (WPGs) for sugi (sapwood and heartwood) and konara veneers were about 50% and 14%, respectively. Ratios of fixation of unleached inorganic substances in WMC veneers were about 80% for sugi and 62% for konara.
OI Values of untreated veneers were 22% regardless of wood species and the presence of leaching procedure, whereas WMC veneers of sugi and konara showed OI values of about 57% and 33%, respectively. The burning time and the percent weight of residual char were increased by combination of wood and silicate. As a result of EPMA observation, carbonized cell walls of untreated veneers became thinner, showing an abnormal shrinkage of tracheids and vessels. In the case of WMC veneers of sugi and konara, silica bodies filled up the lumina of tracheids and vessels or sometimes coated the lumen surfaces, and the abnormal shrinkage of cells and the thinning of cell walls hardly occurred. Also, the distribution of silica in the carbonized walls of tracheids, vessel, and wood fibers was found interestingly, giving a fire retardant effect to WMC veneers together with boron compound. The correlation between WPG and OI was recognized and consequently the evaluation of fire retardancy with WPG would be possible.
In the burning test of WMC veneers with a microburner, the increase in temperature on the upper side of specimen was slow. The ignition of WMC sugi veneer was not recognized in 30 minutes and the carbonized area on the under side of specimen was small. When WMC sugi veneer was directly exposed to fire and OI values estimating from the linear regression equation were more than 60%, the fire retardancy could be evaluated to be better.

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The glueability and fire resistance of wood-mineral composites were investigated, which were made by introducing inorganic substances into wood (buna) veneer using the water glass (sodium silicate)-boron compound system (double treatment). The composites were also made with boron compounds alone (single treatment), and two-ply plywoods were prepared by bonding with a phenol-resorcinol resin adhesive. Dry gluejoint strength was determined by tensile-shear test, and fire resistance was evaluated by burning test using a microburner.
The glue-joint strength was reduced by both single and double treatments in comparison with the untreated wood, and the values for the double treatment were 44% to 65% of the value for the untreated wood. Besides the bulking of the composites and the deterioration resulting from soaking in an alkaline solution, the lessening of a mechanical anchoring effect was considered to be one of the main reasons for the reduction of glue-joint strength by combination of wood and mineral. There was a negative correlation between glue-joint strength and weight percent gain; the strength reduced linearly with an increase in weight percent gain.
The wood-mineral composites showed a good wettability, but it did not contribute to enhance the bonding strength because there was a tendency for the bonding strength to reduce with an increase in contact angles (cosθ). However, the high values of wood failure indicate that the wood-mineral composites have a sufficiently good glueability for practical use in spite of the reduction of bonding strength.
Plywoods prepared from wood-mineral composites had heat-resisting and flame-resisting effects of the single and double treatments. Particularly, the double treatments with boron trioxide, ammonium borate, and boric acid were confirmed to show an excellent fire-resistance effect.

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Four kinds of RF and PRF wood adhesives were prepared and their curing behavior at ambient temperature was evaluated using the TBA method. The TBA curves obtained under isothermal and non-isothermal conditions revealed the difference in curing behaviour among the resins. It was found that curing measurements conducted at a constant heating rate were convinient for the comparison of the curing rate of the resins differing in resorcinol content. On the other hand, measurements carried out at a constant temperature were suitable for the determination of curing characteristics of the resins. It was observed that CH₂O was readily evolved during TBA measurements which affected the curing properties of the resins. Therefore, viscoelastic measurements were carried out for the resin impregnated in glass braid, sealed and cured. The results show clearly that this method is useful for the evaluation of ambient temperature setting properties of the PRF adhesives.

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エチレンに窒素，二酸化炭素またはアルゴンを混合したガス雰囲気下で大気圧プラズマ処理を行った。堆積物のFT－m測定，プラズマ処理後のガスおよび堆較物のメタノール可溶物についてGC-MS測定をそれぞれ行った。プラズマ処理によって生成した堆穣物は含酸素化合物を含んでいた。アルゴンを混合した場合，エチレンのみで処理した場合とほぼ同じ結果を得たが，窒素と二酸化炭素を混合した場合，メチレンが減少し，含酸素化合物が増加した。また，二酸化炭素はプラズマ中で解離し反応種として働くため，他に比べてエステルが増加した。アルゴンはエチレンの反応を促進し残存オリゴマーを減少させるために堆椴膜と基質の親和性が向上した。

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