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Increasing MTBF for Pulp & Paper ClO2 Applications, 20PEERS Conference

Increasing MTBF for Pulp & Paper ClO2 Applications, 20PEERS Conference

Impact of different calendering strategies on barrier coating pickup, TAPPI Journal November 2023

ABSTRACT: Paper was pre-calendered in a pilot scale configuration with a traditional soft nip calender and a metal belt calender. All calendering strategies reduced surface roughness and permeability of the samples, but different strategies affected the surface roughness and permeability differently. The metal belt calender seemed to have a larger effect on the large-scale variations compared to the soft nip calender. Six test points from the pilot calendered papers were chosen for laboratory coating studies. Uncalendered paper was included as reference samples. The calendered samples and the reference were pre-coated with a regular pigmented coating consisting of a ground calcium carbonate (GCC) pigment and a styrene acrylate (SA) latex. Both uncoated and pre-coated substrates were barrier coated with a polyvinyl alcohol (PVOH) in one and two layers. The coating pickup was determined gravimetrically, and the barrier properties were evaluated with TAPPI Standard Test Method T 454 grease resistance test. All samples needed two PVOH coating layers to form a grease barrier. The uncalendered sheets showed the best results with one coating layer, but this was at the expense of a higher coating pickup compared to the calendered sheets. The barrier coating pickup could be reduced by a combination of high temperature metal belt calendering and pre-coating. The high temperature and long residence time in the nip enabled plasticization of the fibers. This led to an irreversible deformation, even after water application. This meant that the smoothness obtained during calendering would be less affected by water-induced roughening during the coating operation.

Use of kaolin clay in aqueous barrier coating applications, TAPPI Journal November 2023

ABSTRACT: Paper-based packaging with barrier effect, as opposed to single use plastics, is gaining more prominence for sustainability reasons. At the same time, latex- or biopolymer-based aqueous barrier coating dispersions are increasingly being adopted as a better alternative to the traditional barrier coating materials, such as wax, surface active chemicals, and polyethylene. In this work, studies were performed to determine the influence of different kaolin clays in latex binder-based aqueous coatings on barrier properties, namely, oil and grease, water resistance, and water vapor transmission rate, by applying coatings to solid bleached sulfate (SBS) paperboard substrate in the laboratory. The aim was to explore potential benefits of using kaolin clay to replace some of the latex binder in coating and improve or maintain various types of barrier performance and blocking without negatively influencing the other performance attributes, including heat seal. The delaminated clay with the highest shape factor provided improved barrier properties over the clays of low shape factor. The ultrafine and non-delaminated clays required significantly higher coat weights to reach satisfactory barrier properties. Coatings with different latex levels indicated that a considerably high proportion of coarse delaminated clay can be incorporated to replace latex binder, while still achieving exceptional barrier properties. Furthermore, a change in binder system was found to significantly alter the barrier properties and the role that a mineral pigment can play. The results indicate that a proper selection of binder systems for each barrier property would be required while considering the clay/latex coating systems.

Online Image Analysis of Nodule Particle-size Distribution for the Control of Lime Kiln Operation, 2023 PEERS Conference

How Many Times Have You Heard the Term Found Money?

How Many Times Have You Heard the Term Found Money? During a recent early morning walk around Peachtree Corners, Ga., I found what I thought was a small pile of leaves. To my surprise, it was a waded

International Research Management at Its Best

International Research Management at Its Best On Nov. 4-7, 2013, 36 of our industry’s’ top research leaders, representing more than 30 institutions, companies, and associations from 10 countries,

Real Measurements Lead to Real Understandings and Better Operating Control of the Recovery Liquor Cycle, 2023 PEERS Conference

Energy efficient alternatives to reduce the carbon emissions in the production of linerboard, 2023 PEERS Conference

TEMPERATURE PROFILE MEASUREMENT APPLICATIONS OF MOVING WEBS AND ROLL STRUCTURES WITH INTELLIGENT ROLL EMBEDDED SENSOR TECHNOLOGY, TAPPICon22

Boosting the elongation potential of paper by mechanical refining and additives, 18PaperCon

Boosting the elongation potential of paper by mechanical refining and additives, 18PaperCon