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Microfibrillated cellulose (MFC) preparation was investigated by means of cellulase pretreatment aided by poly(dimethyldiallylammonium chloride) (polyDADMAC) as an additive. The effect of polyDADMAC on the adsorption of cellulase onto the cellulose fibers, and the properties of MFC and MFC films are described. The additive improved the adsorption of cellulase onto cellulose fibers. Compared to the control, at an addition level of polyDADMAC of 0.789 ml g−1, the crystallinity, aspect ratio, the specific surface area of MFC and, the elongation at break and tensile strength of MFC films are increased, while the oxygen permeability coefficient of the MFC films is decreased. The optimal conditions for preparation of MFC by cellulase pretreatment were: pulp consistency 10%, cellulase dosage 10 µ g−1, pretreatment time 16 h and 0.789 ml g−1 polyDADMAC. In summary, polyDADMAC-assisted cellulase pretreatment enhances the efficiency of the cellulase pretreatment of cellulose fibers and improves the performance of MFC and the MFC films.

In order to investigate the influence of coating layer characteristics on the dynamic permeability and printing of ink-jet paper, coating was prepared by the precipitated calcium carbonate (PCC) and white latex used as bottom coating (recipe label:A,B),and coating formula was made by silica (SiO2) and polyvinyl alcohol used as surface coating (recipe label:a,b,c).Then paper were coated respectively on single bottom, single surface and multilayer. Then the dynamic permeability and printing of ink-jet paper were analyzed systematically. The results showed that whether single layer or multilayer, the values of Ct, Ci were minimum when the ration of pigment and adhesive was 70:30, because the hole diameter of the coating layer was smallest, and the absorption was strongest, so the dynamic permeability was best, and the ability of ink absorption was best, color density and tone reproducibility were best. It concluded that when the proportion of SiO2 and PVA was 70:30, the dynamic permeability and printing ability of ink-jet paper were relative better.

As a kind of environmentally friendly material, microfibrillated cellulose (MFC) has the following advantages: renewable raw materials, easy recycling, biodegradable, safety and so on. It can be combined with antibacterial agents to prepare the antibacterial packing materials for food. In this paper, the nano-ZnO was modified by titanate coupling agent TM-38s at first,determines the best dosage of TM-38 is 3% in the modification process,the dosage of the isopropyl alcohol for 40ml,improving its dispersibility. And then added in the MFC suspension to formulate the antibacterial coating for antibacterial coated paper preparation. The changes of antibacterial properties of the paper before and after coating were investigated in this study. The results showed that the paper had a significant antibacterial activity to e. coli and staphylococcus aureus (the antibacterial circle was bigger than 15 mm).When the nano-ZnO dosage was 2.5wt%, the antibacterial properties of the coated paper could reach the best situation. Application of the antibacterial caoated paper to the food packaging could restrain and kill the microorganisms on the food surface effectively, prolong the shelf life of food, and improve the food safety.

Using UV inkjet printing can achieve three-dimensional printing of ceramic materials, but there is low ink adhesion, easy to fall off and other issues, surface coated modification to high smoothness ceramic materials can solve the above problems [1]. In this study, the silane coupling agent, adhesive, resin and other raw materials prepared for transparent coating, which applied to the surface of the ceramics. The impact of process parameters and coating formulation on the UV print quality of the ceramic base was systematic analyzed, the result shows that the volume concentration of 10% KH550 silane coupling agent as primer, and using 20wt% 102 multipurpose plastic glue for surface coating, better ink adhesion and printing quality can be obtained.

During xerographic printing processes, the electric charge properties of the paper surface are essential to obtain effective toner transfer and high image quality. Surface and volume resistance are indispensable to the accumulation of the surface charge and different resistance values generate different electrical fields with optical drum, and have a significant effect on toner transfer efficiency. In this paper, surface sizing was investigated to improve the surface properties for better toner transfer and image quality. Styrene acrylate emulsion (SAE) latex was successfully synthesized and fully characterized with a Fourier transform infrared (FT-IR) spectrometer, a laser particle analyzer and a scanning electron microscope (SEM). The results showed that under the conditions of emulsifier dosage at 3 wt%, initiator concentration at 0.5 wt% and the reaction temperature at 80°C, the monomer conversion can reach 80%. The effects of various factors including initiator dosage, emulsifier dosage and monomer ratio on the sizing performance were studied. The effects of different ratios of SAE to starch on surface and volume resistance of paper were also systematically investigated. The differences in electric properties of various paper samples were quantified and their influence on paper-toner adhesion and print quality was clarified. Relationships between electrical properties of paper and paper-toner adhesion force, and thus print quality were established. Strategies to improve printing performance through effective control of paper electrical properties were also developed. It is concluded that the best printing quality and toner adhesion were achieved when the ratio of SAE to starch is between 1:10 and 2:10.

With the development of estate and decoration industry, decorative paper become more and more popular, people's needs and requirements are also increasing. However, compared with imported decorative base paper, domestic decorative base paper have a lot of quality problems. In order to improve the performance of domestic decorative paper, surface sizing was used to improve the printing performance and final product quality of domestic decorative base paper in this study. Starch and styrene-acrylic emulsion (SAE) were used as the surface sizing agents for the surface treatment of decorative base paper by the German SUMET coating machine in this paper. Under the conditions of sizing roll pressure of 250N, sizing speed 9m/min, drying temperature and time of 100°C and 70s respective, the effects of metering roller type (No.40 and No.30) and different ratios of starch and SAE ratio (10:1, 15:1, 20:1, 25:1 and 30:1) on the decorative base paper printing performance were investigated in this paper. The optimal sizing conditions and formulation for decorative base paper were as follows: roll pressure 250N, sizing speed 9m/min, drying temperature and time of 100°C and 70s respective, No.30 metering roll, the ration of starch and SAE 20:1. Under this conditions, printing runnability of decorative base paper such as the tensile strength, smoothness were increase greatly and the pH value reached the national standard, the printability such as the color density, tone reproduction range were improved.

UV spectrophotometer was used to measure UV transmittance spectrum of pigment and photo-initiators to identify the light transmitting window of a pigment and photo-initiatorsabsorption peak , then later the types of photo-initiators was determined . In order to determine the optimal assignment of monomers, dispersing agent, defoaming agent and dispersing resin, the uniform design method was supplied to achieve the smallest particle diameter within the range of D95. After the excellent configuration of based ink, the orthogonal design methodwas used to determine the proportion of based ink, photo-initiators, film-forming resin, additives by regarding viscosity, surface tension, curing speed, and color fastness as indicators.

Microfibrillated cellulose (MFC) was prepared from the bleached kraft hardwood pulp using TEMPO/NaClO/NaBr oxidation system and high pressure homogenization. By changing dosages of the TEMPO, NaClO and NaBr, the pressure and times of homogenization, pretreatment and homogenization process were optimized. Experimental investigation indicated that for making MFC of high quality, 0.25%TEMPO, 2.5%NaBr, 60%NaClO (based on oven dry pulp), 20 times of homogenization, pressure of 60MPa in the process of treatment were required. At last, the mechanical and barrier properties were tested after the base paper was coated by homemade MFC. The study suggested that mechanical properties (especially 5 times increase of the folding strength) increased substantially and air permeability decreased by 100times.

Enzymatic refining of eucalypt bleached kraft pulp with the cellulase NOV476 was studied. The effects of this cellulase on the physical properties of pulp, fiber morphology and fiber appearance of the eucalypt bleached kraft pulp in different application conditions were discussed. The results show that, with the increase in the amount of enzyme, tensile strength index, burst index and TEA index of paper are increased and then decreased; elongation and tear index of paper have been declining, Zeeil tensile strength index has been an upward trend. Without beating the pulp sample, gradually increases as the amount of enzyme, the average fiber length and the average fiber width are gradually reduced, while mean kink index substantially constant. Number of vessels in fiber overall reduced tendency reaches a minimum in the amount of enzyme 0.5μ/g, the phenomenon is most obvious. In the same conditions of beating time, gradually increases as the amount of enzyme, the average fiber length is gradually reduced, an average fiber width is gradually increased, the mean kink index reaches a maximum in the amount of enzyme is 0.5μ/g. Number of vessels in fiber overall reduced trend.

Pulp concentration was increased, during preparation of microfibrillated cellulose (MFC), in an effort to improve the efficiency of cellulase pretreatment. It was hypothesized that increased pulp concentration could possibly increase the interactions between cellulase and cellulose, therefore improving the cellulase pretreatment efficiency and benefiting MFC and its film properties. Results showed that higher pulp concentration enhanced the cellulase adsorption ratio from 70% to 90% for pulp concentrations of 2% and 10%, during the pretreatment process. While pulp concentration was changed from 2% to 10% during cellulase pretreatment, the specific area rose from 30.1 m2/g to 35.5 m2/g. Compared with the original eucalyptus pulp, the crystallinity degree of different pulp concentration was increased, presumably due to the enzymatic breakdown of amorphous cellulose. In addition, the aspect ratio of MFC rose from 19.1 to 35.5. Concurrently, MFC film properties showed better performance, as the elongation at break increased from 0.75% to 1.95%, tensile strength increased from 15.3 MPa to 33.5 MPa, and oxygen permeability coefficient decreased from 111×10-14 cm3·cm/cm2·s·Pa to 89.7×10-14 cm3·cm/cm2·s·Pa, reflecting the oxygen barrier properties of MFC film.

The influence of coating layer structure on both physical and printing quality of the paper was studied. Different coating layers were obtained by changing the ratio of polyvinyl alcohol adhesives and silicon dioxide pigments in the coating formula. Then the structure, physical properties and ink-jet printing performance of the coated paper were measured. The influences of coating structure on physical properties and ink-jet printing performance were evaluated. The results showed that as the ratio of adhesive increased, the coating porosity decreased; the average pore diameter increased at first and then decreased, but in general tended to decrease; the initial drop contact angle increased, which testified the stronger hydrophobicity of the coated surface with higher adhesive ratio. The average pore diameter has a negative linear correlation with paper roughness while has a positive linear correlation with air permeability. The larger the average pore diameter, the greater the density values, as well as the better tone reproduction and the larger color gamut range. Average pore diameter also has a weak correlation with dot area and dot roundness.

In order to improve the physical and color laser printing properties of paper, the polyvinyl alcohol and silica were used for pigmental surface sizing of paper. Under the previous conditions of solid content 12% and 14%, the effects of different ratio of PVA and silica such as 100:0, 15:1, 10:1, 5:1, and 1:1 on the physical properties of paper and laser printing performance were investigated. The brightness, opacity, roughness, color density, gray scale and image definition were measured after the surface sizing paper was calendared under the condition of temperature 70°C and pressure 4MPa. When the solid content was 12%, PVA: SiO2 was 1:1 and the solid content was 14%, PVA:SiO2 was 10:1, the brightness and opacity of paper obtained the maximum values. With the increase of silica proportion roughness increased at first and then decreased. Color density and tone reproducibility of paper was significantly improved by the pigmental sizing treatment as well as the dots and lines definition. The reasonable pigmental sizing scheme was as follow: solid content was 12%, PVA:SiO2 was 1:1, sizing temperature was 60°C, calendar temperature was 70°C and calendar pressure was 4MPa.

Some appropriate print samples (according to the ISO standards of ink color values) were selected to set up a mathematical model which showed the relationship between density and color. The model was based on Support Vector Machine algorithm. Another evaluation system was established based on Gray Relation to decide the contribution of K, ΔL*, Δa* and Δb* to density. The final mean square error of the training sample and testing sample was 0.001 and 0.003 respectively. The evaluation system showed that the biggest impact on C，M，Y，K solid ink density was Δa* , ΔL*, K and Δb* respectively, the grey relational degree was 0.7587，0.8340, 0.7591 and 0.8711 respectively. The results of this study indicated that vector machine algorithm could accurately predict density values from chromaticity values and that the grey evaluation system of the solid ink density can be used to evaluate how big the influence of K，ΔL*，Δa*，Δb* on solid density are in offset printing.

In order to improve the optimized performance of bee genetic algorithm, this paper proposed the evolution strategy by introducing immune evolution and chaotic mutation into bee genetic algorithm. This algorithm carries out the chaotic mutation to the some individuals with the lower fitness values, meanwhile the crossover and mutation operations were conducted between the some individuals with the higher fitness values and the optimal individual (queen) in population. In addition, the optimal individual in each generation should make iterative calculation by immune evolution. Therefore, as the iterations go on, this algorithm not only converges faster, but also close to the global optimal solution with higher precision.

Cellulase is potential tool for modification of pulp properties to save energy requirement during refining process. In this paper, bleached Simao Pine kraft pulp was treated with NOV476 cellulase under different enzyme dosage for action mechanism analysis. Pulp viscosity was measured to evaluate the damage of fiber by enzyme. Fourier transform infrared spectroscopy (FT-IR) was performed to study the enzyme treatment on the pulp chemical structure and crystallinity index. The fiber morphology difference before and after treatment was also revealed by the SEM and AFM observation. When the cellulase dosage was lower than 1u/g, the fiber mean length slightly increased. With the further increase of cellulase dosage beyond 1u/g, the fiber mean length was less reduced than the control sample. The fiber mean width increased steadily after enzyme treatment in the dosage range of 0~0.1 u/g. Enzyme treatment did change the fiber chemical structure and crystallinity index through FT-IR analysis. With the increase of NOV476 cellulase dosage, the pulp viscosity decreased steadily. The SEM analysis showed the surface of cellulase treated fiber had some fluffing phenomenon and there was obvious intertexture between fiber and fiber. AFM images further demonstrated that the fiber surface of controlled pulp was covered by primary layer. After enzyme treatment, the primary layer of fiber cell wall was peeled off.

Bleached simao pine kraft pulp was treated with Aspergillus niger crude cellulase produced by submerged fermentation using the pulp as the carbon source. The effects of the cellulase on the pulp beatability and mechanical properties were studied. Fourier transform infrared spectroscopy (FT-IR) was performed to study the effect of cellulase treatment on the cellulose crystallinity index. The fiber morphology difference before and after treatment was also revealed by atomic force microscope observation. Compared to the control pulp, the beating time of the cellulase-treated pulp with the dosage of 7 u/g could be reduced from 360 s to 260 s under the same beating degree of 48oSR, which indicates a savings of about 28% beating energy consumption. The cellulase treatment had negative impacts on the pulp’s mechanical properties. The cellulase preferentially adsorbed on the fine surface. The cellulose amorphous region was easier to treat with cellulase than the crystalline region. Atomic force microscope images demonstrated that the primary wall of fibers was peeled off and the S1 layer of fibers came to the surface after the cellulase treatment.