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This study presents a novel transmission-based method for characterizing local structural features, including the grammage, thickness, and fiber orientation, of paper materials. Some non-destructive techniques, such as micro-computed tomography (μ -CT), microscopy, and radiation-based methods, are costly, time-consuming, and lack the ability to provide comprehensive local structural information within a single measurement. The proposed method utilizes a single light transmission measurement to assess local grammage and thickness through histogram matching with reference data obtained via β -radiography and profilometry. The same light transmission images are also used to determine local fiber orientation, employing image analysis techniques. The structure tensor method, which analyzes gradients of light transmission images, provides detailed insight into the local fiber orientation. The results show that thickness and grammage measurements are independent of which side of the paper is evaluated, while the fiber orientation distribution varies between the front and back sides, reflecting differences in fiber arrangement due to manufacturing processes. Various distribution functions are compared, and the Pearson Type 3, log-normal, and gamma distributions are found to most accurately describe the grammage, thickness, and fiber orientation distributions. The study includes a variety of paper types, ensuring a robust and comprehensive analysis of material behavior, and confirms that the method can effectively infer the inhomogeneous features from a single light transmission measurement. [ABSTRACT FROM AUTHOR]

Grease-proof paper is an energy-demanding paper product to manufacture, especially during refining and dewatering. Increases in energy efficiency in either stage could result in major savings. This article investigates the potential gains with addition of a stepwise progression vacuum suction box to the forming section during production. For both a lighter, 50 g/m2, and a heavier paper grade, 100 g/m2, with a pulp-drainability of 86 °SR, a stepwise progression vacuum suction box in four steps would result in increased dryness, simultaneously with decreased energy expenditure. The observed effects were higher for the lower basis weight paper (50 g/m2). Both basis weights experienced clogging of the forming fabric due to the high degree of refining. This adversely affected the dewatering rate, decreasing the amount of air pulled through the paper even when increasing the vacuum pressure. When a stepwise progression suction box in four steps was compared to a single vacuum suction box, there was a 14% increase in dryness for lighter paper, over an equal energy consumption, measured as amount of air pulled through the paper. For the 100 g/m2 paper, the increase in dryness was 3% compared to the 50 g/m2 paper run over a single vacuum suction box. The results show great promise for energy savings when utilizing stepwise progression suction box dewatering for grease-proof paper production.

Grease-proof paper is an energy-demanding paper product to manufacture, especially during refining and dewatering. Increases in energy efficiency in either stage could result in major savings. This article investigates the potential gains with addition of a stepwise progression vacuum suction box to the forming section during production. For both a lighter, 50 g/m², and a heavier paper grade, 100 g/m², with a pulpdrainability of 86 °SR, a stepwise progression vacuum suction box in four steps would result in increased dryness, simultaneously with decreased energy expenditure. The observed effects were higher for the lower basis weight paper (50 g/m²). Both basis weights experienced clogging of the forming fabric due to the high degree of refining. This adversely affected the dewatering rate, decreasing the amount of air pulled through the paper even when increasing the vacuum pressure. When a stepwise progression suction box in four steps was compared to a single vacuum suction box, there was a 14% increase in dryness for lighter paper, over an equal energy consumption, measured as amount of air pulled through the paper. For the 100 g/m² paper, the increase in dryness was 3% compared to the 50 g/m² paper run over a single vacuum suction box. The results show great promise for energy savings when utilizing stepwise progression suction box dewatering for grease-proof paper production. [ABSTRACT FROM AUTHOR]

This study presents a novel transmission-based method for characterizing local structural features, including the grammage, thickness, and fiber orientation, of paper materials. Some non-destructive techniques, such as micro-computed tomography (μ-CT), microscopy, and radiation-based methods, are costly, time-consuming, and lack the ability to provide comprehensive local structural information within a single measurement. The proposed method utilizes a single light transmission measurement to assess local grammage and thickness through histogram matching with reference data obtained via β-radiography and profilometry. The same light transmission images are also used to determine local fiber orientation, employing image analysis techniques. The structure tensor method, which analyzes gradients of light transmission images, provides detailed insight into the local fiber orientation. The results show that thickness and grammage measurements are independent of which side of the paper is evaluated, while the fiber orientation distribution varies between the front and back sides, reflecting differences in fiber arrangement due to manufacturing processes. Various distribution functions are compared, and the Pearson Type 3, log-normal, and gamma distributions are found to most accurately describe the grammage, thickness, and fiber orientation distributions. The study includes a variety of paper types, ensuring a robust and comprehensive analysis of material behavior, and confirms that the method can effectively infer the inhomogeneous features from a single light transmission measurement.

Analysis of the basis weight for random fibrous networks is important to understand their microstructure, properties and performance. Two-dimensional microscopical images show in-plane fibers without giving any information on their distribution in three dimensions. This research introduces a fully parametric algorithm for computing the local basis weight of random fibrous networks using three-dimensional images because out-of-plane fiber orientation is important, especially for high-density or thick networks. Voxel models of real nonwoven webs were generated by an X-ray micro-computed tomography system. The developed algorithm could accurately estimate a local basis weight value for random fibrous networks produced with various manufacturing parameters. Numerical results computed with the developed method were compared with those obtained with a physical weight measurement technique. The algorithm was tested and validated for various nonwoven fabrics with different densities. It was observed that the developed method can be used to examine and/or compare the basis weight of a wide range of random fibrous networks. In addition, it can be used to predict the basis weight for fabrics, especially in a new product development process. [ABSTRACT FROM AUTHOR]

Cellulose nanofibre (CNF) is the sustainable nanomaterial used for developing high-performance barrier materials that are renewable, recyclable, and biodegradable. The CNF film has very low oxygen permeability; however, its water vapor permeability is significantly higher than that of conventional packaging plastics. The fabrication method influences their barrier properties of the film. A spray-coating CNF on a stainless-steel plate was developed to form a compact film with two unique surfaces, namely a smooth layer on the base side and rough layer on the free side. It improves both the ease of preparation of the film and reduces the water vapour permeability via tailoring the basis weight and thickness of the film through simple adjusting CNF content in the suspension. The air permanence of the film from 1.0 wt.% to 2.0 wt.% CNF suspension is less than 0.003 µm/Pa·S confirming that is an impermeable film and proves a good packaging material. SEM, optical profilometry, and AFM revealed that the spray-coated surface was smooth and glossy. For sprayed CNF films with basis weight between 86.26 ± 13.61 and 155.85 ± 18.01 g/m2, WVP were ranged from 6.99 ± 1.17 × 10−11 to 4.19 ± 1.45 × 10−11 g/m·Pa·S. In comparison, the WVP of 100 g/m2 vacuum filtered CNF film was 5.50 ± 0.84 × 10−11 g/m·Pa·S, spray-coated film (of 96.6 g/m2) also show similar permeability at around 5.34 ± 0.603 × 10−11 g/m·Pa·S. The best performance was achieved with spraying of 2.0 wt.% CNF and a water vapour permeability of 3.91 × 10−11 g/m·s·Pa. Spray coated CNF film is impermeable against air and water vapour and a potential alternative to synthetic plastics.

Cellulose nanofibre (CNF) is the sustainable nanomaterial used for developing high-performance barrier materials that are renewable, recyclable, and biodegradable. The CNF film has very low oxygen permeability; however, its water vapor permeability is significantly higher than that of conventional packaging plastics. The fabrication method influences their barrier properties of the film. A spray-coating CNF on a stainless-steel plate was developed to form a compact film with two unique surfaces, namely a smooth layer on the base side and rough layer on the free side. It improves both the ease of preparation of the film and reduces the water vapour permeability via tailoring the basis weight and thickness of the film through simple adjusting CNF content in the suspension. The air permanence of the film from 1.0 wt.% to 2.0 wt.% CNF suspension is less than 0.003 µm/Pa·S confirming that is an impermeable film and proves a good packaging material. SEM, optical profilometry, and AFM revealed that the spray-coated surface was smooth and glossy. For sprayed CNF films with basis weight between 86.26 ± 13.61 and 155.85 ± 18.01 g/m2, WVP were ranged from 6.99 ± 1.17 × 10−11 to 4.19 ± 1.45 × 10−11 g/m·Pa·S. In comparison, the WVP of 100 g/m2 vacuum filtered CNF film was 5.50 ± 0.84 × 10−11 g/m·Pa·S, spray-coated film (of 96.6 g/m2) also show similar permeability at around 5.34 ± 0.603 × 10−11 g/m·Pa·S. The best performance was achieved with spraying of 2.0 wt.% CNF and a water vapour permeability of 3.91 × 10−11 g/m·s·Pa. Spray coated CNF film is impermeable against air and water vapour and a potential alternative to synthetic plastics. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cellulose sheets with different basis weight and beating degree were prepared, and gas grafting was performed under high temperature and high pressing pressure conditions. Then, the grafting efficiency expressed in the grafted fatty acid content and the like was analyzed. As a result, it was found that the grafted fatty acid content per square meter of cellulose sheet increased by 78.15 mg/m2 as the sheet basis weight doubled from 100 g/m2 to 200 g/m2. This is due to more hydroxyl groups per equal area due to the higher basis weight. However, when the freeness of fibers reduced from 500 mL CSF to 300 mL CSF by beating, the grafted fatty acid content of the cellulose sheet per square meter decreased as low as 48.02 mg/m2. This can be attributed to both the decrease in the accessible hydroxyl group content per equal area and the decrease in the porosity of the cellulose sheet. Both of these phenomena are caused by beating of fibers. [ABSTRACT FROM AUTHOR]

Basis weight distribution of melt-blown fibrous web is attracting considerable interest because it directly affects the application performance of nonwovens. Basis weight distribution is strongly determined by the air velocity distribution on the top surface of the collector. However, how the mentioned air velocity distribution affects basis weight distribution is still unknown. Measurement of the mentioned two distributions is the first step to investigate the influence mechanism. Thus, this work measures air velocity distribution on the collector under different processing conditions. Then the fibrous web is fabricated under same conditions. After fabrication, the basis weight distribution of fibrous web is analyzed by using image analysis method. The effects of processing conditions, including velocity of air jet and suction, die-to-collector distance, and pore size of the collector, on the air velocity distribution and basis weight distribution are quantitatively analyzed. The results demonstrate that higher suction speed and air jet velocity, smaller die-to-collector distance, and larger pores of the collector result in higher air velocity on the top surface of the collector. On the other hand, higher suction speed and air jet velocity, larger die-to-collector distance, and smaller pores of the collector create evenly distributed basis weight. In addition, the correlation between basis weight distribution and air velocity distribution is discussed based on the Spearman correlation analysis method. High correlation demonstrates that air velocity and basis weight display similar distribution on the collector. Namely, both of air velocity and basis weight in the central zone are larger than those in the fringe zone on the collector. [ABSTRACT FROM AUTHOR]

Purpose. Ensuring the determination of the basis weight of the textile fiber mass directly during the manufacturing process using an ultrasonic device equipped with non-contact ultrasonic sensors. In particular, show the effect of the basis weight of a textile fiber mass on the amplitude of probing vibrations in the measuring channel of an ultrasonic device. . Methodology. An amplitude control method is proposed, which is the basis of the operation of the ultrasonic device. It consists in irradiating the textile fiber mass, which moves relative to the scanning bracket with the sensors, and determining the basis weight of the fiber mass by reducing the amplitude of the ultrasonic waves in the measuring channel. The measurement results are processed with their subsequent digitization and computer analysis. . Findings. It has been established that due to the passage and re-reflection of ultrasonic waves, which fall on two receivers with different vibration delays, it is possible to increase the accuracy of measurements of the average values of the basis weight of the textile fiber mass. Originality. In the general case, it is established that by passing and reflecting ultrasonic waves entering two receivers with different delay of oscillations, it is possible to increase the accuracy of measurements of average values of basis weight of textile fiber mass. Practical value. The block diagram of the ultrasonic device for determination of basis weight of textile fiber mass is shown and its work is described. The main dependences on which the device system will determine the basis weight of the textile fiber mass are also given. [ABSTRACT FROM AUTHOR]

Purpose. Investigate the influence of single-layer textile fabrics and two-layer textile bags on the parameters of ultrasonic waves that interact with them. In particular, to investigate the dependence of the complex reflection coefficient of ultrasonic waves on the total thickness and basis weight of textile material. Methodology. The analytical part of the study consisted in obtaining an expression for the complex reflection coefficient of ultrasonic waves and in modeling its dependence on the thickness and basis weight of different textile materials. The proposed method of control of these technological parameters consists in irradiation of textile materials with ultrasonic waves with the subsequent reception of the waves reflected from textile material, their digitization and carrying out the computer analysis of the received results. Findings. Analytical expressions are obtained that relate the thickness and basis weight of single layer canvases, two-layer textile bags with a complex spatial structure, on the one hand, and the reflection coefficient of ultrasonic waves from such materials, on the other hand. Analytical calculations were made and mathematical modeling was performed based on the results of theoretical research. Originality. As a result of theoretical studies, it is determined how the thickness and properties of each of the two layers of porous textile materials affect the reflection of ultrasonic waves. This makes it possible on the basis of ultrasonic measurements to determine both the total thickness of textile materials and their basis weight with the accuracy required for their production. Practical value. The obtained analytical dependences are another step towards the creation of control and measuring equipment to determine the properties of single-layer textile fabrics and two-layer porous textile bags. This will help determine the overall thickness and basis weight of materials with a complex spatial structure. [ABSTRACT FROM AUTHOR]

The papermaking process is a typical nonlinear process with multiple input-output variables, so it is difficult to construct an accurate model for the process. Data-based modeling techniques may be used to establish a reliable paper plant model. In particular, the LSSVM (least-squares support vector machine) can be used to create a highperformance papermaking process model based on operation data. In this paper, we present a paper plant model that can predict three key output variables (basis weight, ash content, moisture content) with four input variables (stock flow, filler flow, speed, steam pressure) using LSSVM. The proposed LSSVM model is compared with other data-based models (the ANN (artificial neural network) model and the state-space model). The LSSVM model turned out to exhibit better estimation performance compared to others. [ABSTRACT FROM AUTHOR]

[Objective]The present paper aimed to search for some technical methods which could reduce the tar content of reconstituted tobacco effectively. [Method]The effect of some factors such as ratio of stems to leaves, beating degree, basis weight, coating rate, proportion of plus fiber and calcium carbonate on the tar content of paper-making reconstituted tobacco was studied and those factors that could reduce the tar content effectively had also been verified. [Result] (i)Beating degree, basis weight, proportion of plus fiber, potassium salt and calcium carbonate had significant influence on the tar content of paper-making reconstituted tobacco;(ii)The ratio of stems to leaves of raw materials also had a certain influence on the tar content of paper-making reconstituted tobacco, and the tar content was the lowest when the ratio of stems to leaves was 2-1;(iii)There was a positive correlation between the coating rate and the tar content of paper-making reconstituted tobacco, the increase of coating rate would lead to the increase of tar content.(IV) The tar content of paper-making reconstituted tobacco prepared under a set of factors, including fiber proportion, beating degree, basis weight had fallen by more than 50 % ,and blending it in cigarette products had also reduced the tar content of cigarettes obviously. [Conclusion] The tar content of reconstituted tobacco could be reduced by adjusting the process parameters. While the PRT sample integrated with some tar-reduced factors was blended into cigarettes, it could greatly reduce the tar content of cigarettes. Therefore, some technical methods could be taken properly to reduce the tar content of PRT, and achieve ‘ reducing the harmful and tar content’ after blending it into cigarettes. [ABSTRACT FROM AUTHOR]

In this research work, the authors have investigated the needling effect on a non-woven prepared form the webs of equal basis weight. Punch density, needle penetration depth and strokes per minute are taken as variables. Initially, it was observed that the punching parameters were influencing the fibre orientation to a great extent. Subsequently, other properties were taken into study. It was found that higher punch density and penetration depth spreading the web in its cross direction, as a result, the basis weight and thickness reducing in a great extent and other properties like basis weight, tensile strength got affected. Secondly, with the change of stroke frequency, the width of the web, as well as nonwoven, also changed due to the spreading towards the cross direction. It was found that when strokes per min increased, the basis weight thickness decreased as well as other properties got affected. [ABSTRACT FROM AUTHOR]

Highlights • scanner path utilized as a manipulatable variable in paper machine cross-directional control. • faster response to load disturbances. • estimation of process noise and basis weight estimate uncertainty based on web-wide transmittance measurement. • adaptive model between transmittance and basis weight. ABSTRACT The cross-directional (CD) basis weight control on paper machines is improved by optimizing the path of the scanning measurement. The optimal path results from an LQG problem and depends on how the uncertainty of the present estimate of the basis weight and the intensity of process noise vary in CD. These factors are assessed by how accurately the CD basis weight estimate predicts the measured optical transmittance with a linear adaptive model on synchronized basis weight and transmittance data. Simulations on optimized scanner path in disturbance scenarios are presented, and the practical implementation of scanner control is discussed. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of the study is to design and develop an instrument for non-destructive measurement of basis weight of fabrics. Weight per square meter is a major product quality of textile materials but its control during production is still limited. The observed dependency of the amplitude pulsed ultrasonic signal transmitted through a textile material on its basis weight informed the recommendation of this method for determining the basis weight of fabrics. The ultrasonic method of non-destructive testing of basis weight of textile materials has been incorporated into the experimental system. We investigated the basis weight of woven fabrics using the proposed ultrasonic system and the standard method and the results show high correlation. It is concluded that the proposed ultrasonic method can be used for the continuous operational control of the basis weight of textile materials during production. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Microfibrillated cellulose (MFC), TEMPO-pretreated MFC, and hybrid polymer/MFC mix were used for the production of layered films with interesting properties for application in food packaging. The series of samples were prepared from MFC (base layers) using a dispersion-casting method. The same procedure as well as a bar coating technique was applied to form top layers of different basis weights. The barrier properties and formation of the layered films were investigated in relationship to the preparation procedures, combination of layers, and areal weight (basis weight). Characterization was done with respect to oxygen transmission rates (OTR), water vapor transmission rates (WVTR), tensile properties, and contact angles (CA) with water. The produced layered films yielded OTR values of 4 mL m-2 day-1 and fulfilled oxygen barrier requirements for a modified atmosphere packaging (MAP). Hornification of the MFC films, however, occurred during drying, which may result in a loss of the film’s beneficial properties.

Nanofibrous layer performs as a membrane that vibrates at low frequencies. This property is obtained by nano dimensions of the interfiber areas. Sound waves incident on the acoustic resonance membrane make the membrane oscillate, and the maximum amplitude occurs in the case of resonance. The structures based on the nanofibrous layers are employed for low-frequency sound absorption. The resonance of the nanofibrous elements allows acoustic energy to be converted into thermal energy. In this article, a nanofibrous layer was produced by electrostatic spinning from an aqueous solution of polyvinyl alcohol and the resonance effect of nanofibrous layer was studied. For this purpose, the new method developed for determination of resonance frequencies of a membrane was employed. The ultimate objective of the study was to assess the effect of mass per unit area on resonance frequencies of the membrane placed in an open and closed tube. The results indicated that the resonance frequencies of the membrane decreased with an increase of the mass per unit area of the nanofibrous membrane. Except for the lowest frequencies (first resonance peak), the resonant behavior of the membrane was affected by the resonance of tube. [ABSTRACT FROM AUTHOR]

Basis weight uniformity can affect various properties of fibrous porous networks, including their porosity and mechanical behaviour. In this paper, a novel numerical technique based on the well-known quadrant analysis method is introduced to statistically quantify the uniformity of fibrous porous networks in the computer environment. First, four fibrous porous networks with different uniformity levels were generated with the in-house script. Then, uniformity was computed numerically based on basis weight analysis for various quadrant sizes for these fibrous porous networks. Uniformity parameter commonly used for quality control purposes turns into design parameter that can be used to optimise the microstructure of fibrous porous networks before manufacturing them with the developed algorithm. [Display omitted] • A novel numerical technique to measure uniformity of fibrous networks. • The algorithm eliminates the limitations of visual inspection methods for networks. • Networks with different uniformity levels are generated with an in-house script. • Quadrant analysis is employed to evaluate uniformity of porous networks. • Coefficient of variation method is utilized to assess uniformity quantitively. [ABSTRACT FROM AUTHOR]

It is widely recognized that nonwoven basis weight uniformity affects various properties of nonwovens, including appearance, physical properties, or mechanical properties. However, it is one of the nonwoven characteristics that is most difficult to characterize. This paper reports on the methodology based on the well-known quadrant method that objectively quantifies uniformity of nonwoven fabrics. [ABSTRACT FROM AUTHOR]

Microfibrillated cellulose (MFC), TEMPO-pretreated MFC, and hybrid polymer/MFC mix were used for the production of layered films with interesting properties for application in food packaging. The series of samples were prepared from MFC (base layers) using a dispersion-casting method. The same procedure as well as a bar coating technique was applied to form top layers of different basis weights. The barrier properties and formation of the layered films were investigated in relationship to the preparation procedures, combination of layers, and areal weight (basis weight). Characterization was done with respect to oxygen transmission rates (OTR), water vapor transmission rates (WVTR), tensile properties, and contact angles (CA) with water. The produced layered films yielded OTR values of 4 mL m-2 day-1 and fulfilled oxygen barrier requirements for a modified atmosphere packaging (MAP). Hornification of the MFC films, however, occurred during drying, which may result in a loss of the film's beneficial properties. [ABSTRACT FROM AUTHOR]

Abstract: The supervised learning method and quality capability of process used in an on-line optical transmission inspection system of the basis weight for nonwoven material are investigated. A near-infrared light transmission inspection is applied in the production machine of a nonwoven fabric to detect the basis weight and support the producing quality. Using least squares method, the parameter transfer equations of the piecewise ploynomials functions between the measured voltage and the nonwoven basis weight are found. Supervised learning method is adopted to improve the producing capability. It is shown that the capability index of process Cp and Cpk is testing samples when the supervised learning algorithm is used. Obvious, the supervised learning method is effective to improve the producing capability and support the producing quality. [Copyright &y& Elsevier]