瓦楞纸板柔印最佳压力调节的研究

在瓦楞纸板直接柔印过程中,印刷压力的精确控制是油墨精确转移、印刷图文准确再现和减少瓦楞纸板物理性能损失的关键条件.本文通过调节印版滚筒和压印滚筒之间的间隙△L,改变印刷压力,定量研究了印刷压力变化对瓦楞纸板柔印品质的影响.实验分析和测量了印版表面油墨转移效果及网点增大值;测试了瓦楞纸板印刷前后的厚度、耐破度、戳穿强度、边压强度及粘合强度变化等.实验结果表明:7.5mm厚的AB型5层瓦楞纸板采用硬度36HSA、厚度3.94mm的杜邦柔性树脂版印刷时,最佳压力为间隙△L=10.9mm,此时柔性版适时厚度为3.73mm,瓦楞纸板适时厚度为7.17mm,减压后纸板厚度为7.30mm,厚度压缩了2.7％.本研究对于高品质瓦楞纸板的研发具有一定的理论指导意义.     

Investigation of physical and mechanical properties of oil palm wood core sandwich panels overlaid with a rubberwood veneer face

Low-density sandwich panels consisting of an oil palm wood core overlaid with a rubberwood veneer face were manufactured. Effects of two types of grain orientation of the oil palm wood core (parallel and perpendicular to board surface) and three different veneer thicknesses (0.7, 1.8 and 2.7 mm) and core densities (223 ± 14, 301 ± 35 and 418 ± 33 kg/m³) on some physical and mechanical properties of the boards were investigated. Results showed that higher core density increased the values of thermal conductivity, screw withdrawal resistance, modulus of rupture and modulus of elasticity but decreased the value of water absorption without effect on thickness swelling of the boards. Boards with the core grain direction oriented perpendicular to panel’s surface possessed lower value of thickness swelling but higher values of thermal conductivity and strain at fracture when the board failed in a mode of core shear under bending test than those of the others. Finally, the relationship between board density and the measured physical and mechanical properties of the oil palm wood core sandwich panels overlaid with a rubberwood veneer expressed as mathematical equations could be used to predict and design the expected properties of this type of sandwich board.     

Thermal conductivity and water vapour transmission properties of wood-based materials

For several wood-based materials (plywood, OSB, melamine faced board (MFB), particle board and fibre board), the thermal conductivity was determined as a function of the temperature (ranging between 10 and 30 °C) and also the moisture content (from an oven-dry sample up to a moisture content at 80% RH). Furthermore, the water vapour resistance factor of these materials as well as of the coating (at MFB) and the diffusion coefficient were determined under dry cup (performance at low humidity dominated by vapour diffusion) and wet cup (performance at high humidity with liquid water and vapour transport) conditions. Thermal conductivity increases with rising temperature, moisture content and density. Moreover, a clear decrease of thermal conductivity was found with decreasing particle size at the same density level, from solid wood over plywood and particle board to fibre board. The water vapour resistance factor of the wood-based materials increases with rising density and decreases with increasing moisture content. An influence of the particle and fibre board thickness was also revealed. In contrast to the remaining materials, an increase of the water vapour resistance factor with increasing moisture content was measured for the coating. The diffusion coefficient decreases with rising density and moisture content.     

覆铜箔板纸的技术进展

介绍了覆铜箔板纸的用途,覆铜箔板的制造过程和应用.分析了覆铜箔板纸的性能与覆铜箔板性能的关系,总结了玻璃纤维覆铜箔板纸和纺纶纤维覆铜箔板纸的技术概况.提出了造纸行业要加强与其他行业的协作,在原料、制造工艺方面不断革新,开发出满足覆铜箔板行业发展需要的新产品.     

农作物秸秆人造板工业化生产现状

介绍了农作物秸秆的种类和应用途径,概述了农作物秸秆人造板的产品品种以及目前国内农作物秸秆人造板工业化生产的现状.     

涂布白纸板的印刷适性

涂布白纸板广泛应用于包装装潢印刷，采用高速多色的胶印时，对其印刷性能提出更高的要求，本文就白纸板的印刷适性进行探讨，寻求最佳的印刷匹配。     

Prediction of timber bending strength and in-member cross-sectional stiffness variation on the basis of local wood fibre orientation

Machine strength grading of structural timber is based upon relationships between so called indicating properties (IPs) and bending strength. However, such relationships applied on the market today are rather poor. In this paper, new IPs and a new grading method resulting in more precise strength predictions are presented. The local fibre orientation on face and edge surfaces of wooden boards was identified using high resolution laser scanning. In combination with knowledge regarding basic wood material properties for each investigated board, the grain angle information enabled a calculation of the variation of the local MOE in the longitudinal direction of the boards. By integration over cross-sections along the board, an edgewise bending stiffness profile and a longitudinal stiffness profile, respectively, were calculated. A new IP was defined as the lowest bending stiffness determined along the board. For a sample of 105 boards of Norway spruce of dimension 45 × 145 × 3,600 mm³, a coefficient of determination as high as 0.68–0.71 was achieved between this new IP and bending strength. For the same sample, the coefficient of determination between global MOE, based on the first longitudinal resonance frequency and the board density, and strength was only 0.59. Furthermore, it is shown that improved accuracy when determining the stiffness profiles of boards will lead to even better predictions of bending strength. The results thus motivate both an industrial implementation of the suggested method and further research aiming at more accurately determined board stiffness profiles.     

纸板成形器的选用与发展趋势

纸板成形是影响纸板质量的重要部分,而成形器则是纸板成形的关键设备。本文试述纸板成形器的选用与发展趋势,供同行参考。     

秸秆板的切削加工质量和胶黏性能

通过对秸秆板家具板件进行锯解,砂光钻孔以及胶黏试验,秸秆扳与普通刨花板的切削加工和胶黏性能比较。结果显示,秸秆板家板件的切削加工质量和胶黏性能均能达到相关的国家标准。     

Abbau von UF-Harzen beim TMP- und CTMP-Aufschluss von mitteldichten Faserplatten (MDF)

Thermo-mechanical (TMP) and chemo-thermo-mechanical pulping (CTMP) of UF-bonded MDF induce considerable degradation of the UF-resin in the board and lead to a conspicuous increase in the content of water extractives of the fibres. Moreover, the water extractives of the fibres have a higher pH-value and a lower buffering capacity as well as higher acetate and formate ions content than the extractives of the original board. However, the lignin content seems rather to increase than to decrease. This is possibly due to reaction between lignin and formaldehyde from the resin.     

Procedural influence on the properties of particleboards made from AKD modified chips

Wood chips were treated with alkyl ketene dimer (AKD) using three different processes to impart water resistance to particleboards. In the first process, AKD was blended with UF resin. Thickness swelling and water uptake after a 24 h immersion period (20 and 69%) were lower than in the control boards (28 and 81%) but were higher than in the paraffin references (10 and 22%). In process 2, AKD and UF resin were sprayed separately on the chips resulting in a greater reduction of thickness swelling (15%) and water uptake (49%) than in process 1. Paraffin references revealed a thickness swelling and water uptake of 7 and 25%, respectively. An extension of the pressing time in processes 1 and 2 did not increase water repellence. In process 3, particleboards were made from AKD-treated chips that were cured at 130 °C (24 h) prior to gluing. They showed a thickness swelling of 7% and a water uptake of 25%, whereas particleboards with paraffin exhibited levels of 8 and 29%. The thickness swelling and water uptake of boards with AKD increased when the curing time was reduced from 24 to 12 to 6 h (130 °C). Changing the curing temperature from 130 to 100 °C (12 h) had no effect on board properties. The IB of boards made from pre-cured chips with AKD (24 h/130 °C) was 44% lower than in controls and 35% lower than in paraffin references. This indicates that AKD impedes the adhesion.     

木纤维增强水泥板的应用

简要介绍了水泥刨花板、水泥纤维板、水泥木丝板的生产工艺和产品应用.     

木雕花板在现代家居设计中的应用

中国传统木雕花板是古代建筑和家居设计中重要的组成部分,不仅具有精美的装饰图案,而且体现出深厚的文化底蕴。本文研究了木雕花板在室内装饰和家具设计中的运用方法,通过实例阐释了木雕花板在墙面装饰、空间隔断、顶棚装饰以及家具设计中所起到的装饰效果。通过以上研究可以为设计师开发新的木雕花板和在家居设计中创造性地使用木雕花板提供指导。     

针板布针设计浅谈

论述了针板上针孔杂乱排列的理论依据、设计针板布针的基本方法及对针板适用范围的确定     

竹织物增强竹碎料板生产工艺研究

将竹材加工剩余物加工成一定规格形状的竹碎料,在竹碎料之间放置数层竹席组成板坯,然后热压成竹织物增强竹碎料板.该板材的静曲强度达到38.6 MPa,弹性模量2 908 MPa,内结合强度1.25 MPa,2 h吸水厚度膨胀率1.04%.该板材既使竹材加工剩余物得到充分利用,又克服了竹碎料板力学性能较差的缺陷.     

瓦楞纸板飞剪控制系统的设计及应用

针对瓦楞纸板横切机剪切精度,设计了一种飞剪模糊自适应PI控制。该系统应用模糊控制理论对飞剪系统进行了参数优化,将飞剪位置比例调节控制改进为阶梯型位置控制环。结合西门子S7-300PLC,将瓦楞纸板生产线的剪切精度从±1mm提升到±0. 5mm以内,满足实际生产要求。     

烟包用涂布白卡纸国内发展概况

介绍了烟包用涂布白卡纸的特性及质量要求,分析了国内烟包市场概况及烟包用白卡纸的市场前景,综述了国内白卡纸的生产情况,进行了市场需求分析和预测。     

纸板结构对模切刀寿命的影响

探索多层纸板的结构对模切刀寿命的影响.一般认为模切刀寿命受涂布颜料、填料、纸板的紧度和可压缩性等因素影响,研究结果显示提高纸板的松厚度(即降低其紧度)有利于延长模切刀寿命,模切刀寿命与切割时需要的能量存在一定的相关性.     

论居室装饰中地板的合理选择

健康、环保的木地板在目前浪潮汹涌的装饰装修热潮中,越来越受到人们的青睐。木 地板以其自身特有的自然、舒适、温馨成为地面装饰的首选之物。本文介绍地板的作用、选择 与装饰美学,力争为家居装饰提供参考。     

Clearance wear and normal force of TiN-coated P30 in cutting hardboards and wood-chip cementboards

This paper presents the clearance wear and normal force characteristics of TiN coated P30 when cutting hardboards and wood-chip cement boards. Hardboards and wood-chip cement boards of low density (about 0.8 g/cm³) and high density (about 1.2 g/cm³) were cut by using TiN coated P30. Cutting tests were performed at a cutting speed of 1000 m/min and a feed rate of 0.1 mm/rev to investigate the effect of the work materials on the clearance wear and normal force characteristics of the TiN coated P30. The experimental results showed that the TiN coated P30, compared to uncoated P30, is more advantageous in reducing the progression of wear on the clearance face, and in retaining lower normal force in cutting both hardboards and wood-chip cement boards. The amount of clearance wear suffered by the TiN coated P30 for the wood-chip cement board was larger compared to that for the hardboard. Though the TiN coated P30 suffers higher wear for the low density wood-chip cement board than the low density hardboard, its normal force, however, is always lower for the low density wood-chip cement board. It was observed that the clearance wear of the TiN coated P30 occurs due to delamination of TiN film and the wear of the substrate occurs after the coating film was disappeared from the substrate.