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The understanding of what properties the fibre should have in order to give the right end-product paper properties, along with the type of processing, is a subject for a lot of research and development. Today the ability to measure fibre properties on-line is widely used for pulps. It is often necessary to measure many properties and variables in a process. The data collected is therefore almost always multivariate. It is very hard to analyse process data due to a lot of noises. Correlations between fibre and paper properties are hard to find, but this does not mean that correlations do not exist. Fibre properties, measured by the pulp analyser PulpEye, were investigated and correlations to paper properties were studied. The work was divided into three different studies. Study 1 was an investigation of historical process data, in study 2 pulp samples from the production was analysed and study 3 was a refiner setting trial, were different refiner segments, flows through refiners and intensities were studied. Both the group-plots and MVDA’s based on the historical process data in study 1, showed that the Scott Bond was increased with increased amount of kinks and curl for the unbleached pine pulp (softwood pulp). Coarseness measurements, made in the study of historical data, indicated that the coarseness was varying in such a large extent that it was believable that it had effects in the papermaking process. Another interesting fibre property, investigated in the refiner setting trial, was crill. The amount of crill is said to have strong correlation to paper strength. The analysis showed that the incoming pulp had different amount of crill and that the amount of crill after the refiners also was varying for the different samples. The development of crill at different kappa numbers and for pulps refined with different segments and refiner strategies should be further investigated. In this work it has been difficult to find correlations between fibre properties and paper properties in the refiner setting trial. This could have been due to small variations of the different parameters. This work showed that the normal production can be handled very well and variations are rather small. It can be seen though, that problems do appear when parameters are deviating from the normal case. An efficient way to work is to do measurements when the incoming pulp parameters are deviating. It should also be more investigated how the most common deviating pulp parameters should be handled in the refining process and at the board machine. The communication between the pulp production and the board machines is recommended to be further developed, especially when the pulp production have disturbances that can be affecting the refining and further the board production.

The understanding of what properties the fibre should have in order to give the right end-product paper properties, along with the type of processing, is a subject for a lot of research and development. Today the ability to measure fibre properties on-line is widely used for pulps. It is often necessary to measure many properties and variables in a process. The data collected is therefore almost always multivariate. It is very hard to analyse process data due to a lot of noises. Correlations between fibre and paper properties are hard to find, but this does not mean that correlations do not exist. Fibre properties, measured by the pulp analyser PulpEye, were investigated and correlations to paper properties were studied. The work was divided into three different studies. Study 1 was an investigation of historical process data, in study 2 pulp samples from the production was analysed and study 3 was a refiner setting trial, were different refiner segments, flows through refiners and intensities were studied. Both the group-plots and MVDA’s based on the historical process data in study 1, showed that the Scott Bond was increased with increased amount of kinks and curl for the unbleached pine pulp (softwood pulp). Coarseness measurements, made in the study of historical data, indicated that the coarseness was varying in such a large extent that it was believable that it had effects in the papermaking process. Another interesting fibre property, investigated in the refiner setting trial, was crill. The amount of crill is said to have strong correlation to paper strength. The analysis showed that the incoming pulp had different amount of crill and that the amount of crill after the refiners also was varying for the different samples. The development of crill at different kappa numbers and for pulps refined with different segments and refiner strategies should be further investigated. In this work it has been difficult to find correlations between fibre properties and paper properties in the refiner setting trial. This could have been due to small variations of the different parameters. This work showed that the normal production can be handled very well and variations are rather small. It can be seen though, that problems do appear when parameters are deviating from the normal case. An efficient way to work is to do measurements when the incoming pulp parameters are deviating. It should also be more investigated how the most common deviating pulp parameters should be handled in the refining process and at the board machine. The communication between the pulp production and the board machines is recommended to be further developed, especially when the pulp production have disturbances that can be affecting the refining and further the board production.

Bomullsfibern har många fördelaktiga egenskaper som gör den allmänt omtyckt bland både konsumenter och producenter. Den vanligaste framställningen av fibern är konventionellt odlad bomull, men dessvärre har denna typ av framställningsprocess en negativ inverkan på miljön i form av hög kemikalieförbrukning och hög vattenanvändning. I samband med att bomullens negativa miljöpåverkan uppmärksammas, bidrar det till en ökad efterfrågan på miljövänliga fibrer med skonsammare processer. Denna studie har utifrån detta perspektiv undersökt, jämfört och testat förutsättningarna för att helt eller delvis ersätta bomull i trikåmaterial. De fibrer som har undersökts är de regenererade cellulosafibrerna Tencel, lyocell och modal. Dels har två hundraprocentiga material testats: Tencel A100 och lyocell, dels två fiberblandningar: bomull/modal och GOTS-bomull/Tencel LF. Samtliga material har bestått av rågarn med garntjocklek Ne 30/1 och stickats fram i en rundstickningsmaskin. Testerna som har utförts rör dimensionsstabilitet, spiralvridning, noppbildning, nötningshärdighet och slutligen draghållfasthet. För att säkerställa trovärdiga resultat har testerna genomförts upprepade gånger och därefter har ett medelvärde för varje material beräknats. De material som uppvisat bäst resultat avseende egenskaper och miljöpåverkan var Tencel A100 och lyocell, samt fiberblandningen GOTS-bomull/Tencel LF. / The cotton fiber has many advantageous properties which make it widely popular among both consumers and producers. The most common production of the fiber is conventionally grown cotton. This type of manufacturing process has unfortunately a negative impact on the environment because of its high chemical consumption and high water use. Since the negative environmental impact regarding cotton has got more attention, it has contributed to an increased demand for more environmentally friendly fibers with more eco-friendly processes. From this perspective, this study has examined, compared and tested the conditions for completely or partially replacing cotton in knitted materials. The fibers that have been examined are the regenerated cellulose fibers Tencel, lyocell and modal. Tencel A100 and lyocell have been tested independently and two fiber blends consisting of cotton/modal and GOTS-certified cotton/Tencel LF have been knitted and tested in this study. All materials have consisted of raw yarn with yarn thickness of Ne 30/1 and has been knitted in a circular knitting machine. The tests that have been carried out is dimensional stability, twisting, pilling resistance, abrasion resistance and finally tensile strength. To ensure reliable results, the tests have been done repeatedly and then an average value for each material has been calculated. The materials that showed the best results in terms of properties and environmental impact were Tencel A100, lyocell and the fiber mixture GOTS-certified cotton/Tencel LF.