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Paper and paperboard are the most utilized packaging materials in the world. This position has been achieved due to several advantageous features of paper such as: renewability, biodegradability, recyclability, and unmatched printability. Paper can be produced anywhere in the world, using local resources and at relatively low cost, which also makes it the most sustainable packaging material. Despite these beneficial features, paper packaging is in tough competition with plastic materials. The competitiveness of paper is mitigated by barrier properties, sensitivity to moisture, and limited ability to be converted into advanced 3D shapes with added functionality. The ability of paper and paperboard to be formed into 3D shapes is described as formability, or sometimes, mouldability. Formability can be defined as the ability of paper to be formed into 3D shapes without defects in appearance and functionality. Formability as a mechanical property represents a group of parameters which vary according to the type of forming process used. The primary objective of this thesis is to improve the formability of paper by increasing its extensibility. An additional objective is the characterization of formability as a mechanical property of paper and the development of a testing platform for the evaluation of formability. It was found that the formability of paper in fixed blank forming processes is governed by the extensibility and tensile strength of paper. On the other hand, in sliding blank forming processes, it is dependent on the compressive properties of paper, elastic recovery, and the paper-to-metal coefficient of friction. The criteria of good formability are also different in these two cases, as fixed blank process formability is evaluated via the maximum depth of the shape, i.e. the deeper the shape, the better the formability. In the sliding blank process, formability is evaluated via the visual appearance of the shapes, i.e. the shapes with less profound compressive wrinkles and defects reflect good formability of paper. These results were established by comprehensive investigation of different forming processes and comparison of the outcome with the mechanical properties of paper. Taking into account the hypothesis that the formability of paper is governed by the extensibility of paper, a set of methods for its improvement was suggested. These methods included combined high- and low-consistency treatment of fibres, spraying of agar and gelatine, in-plane compaction of paper and unrestrained drying. High-consistency treatment of fibres under elevated temperature induces permanent deformations to fibres such as microcompressions and dislocations, which in turn may decrease the axial stiffness of fibres, promoting shrinkage of paper and fibres. The low-consistency treatment straightens the fibres and induces the fibrillation of fibres to promote bonding, while microcompressions in fibres still exist. The spraying of agar and gelatine is likely to modify the character of the fibre joints by making them more deformable, and the drying shrinkage is also increased due to polymer addition. Finally, the fibre network was subjected to in-plane compaction and drying shrinkage which lead to buckling and fibre and network compression. As a result of these treatments, the extensibility of unrestrained dried paper was increased from 4% points (untreated fibres) to 15-18% points (mechanical treatment and addition of polymers). The extensibility can be increased further by up to 30% points in one direction by compaction. This corresponds to tray-like shapes with a depth of 2-3 cm, depending on the curvature. Such values of formability are the highest reported so far in the scientific literature. The approach for the production of formable paper developed in this thesis work allows the production of a paper-based material with unmatched formability, which can replace certain types of plastic packaging. Replacement of plastics with paper improves the sustainability of packaging in general, and reduces the harmful environmental impact of non-degradable and non-renewable packaging.

Novel types of fibre-based packaging materials are the promising direction in the product portfolio of modern biorefineries. Despite of the adavantageous features of fibre-based packaging material such as: biodegradability, recyclability and renewability, it is lacking the level of formability that plastic packaging materials do have. The formability of material determines how advanced shapes can be formed for the end product. In respect to the paper-based packaging, high formability would allow to produce containers, trays, shells etc. with an advanced design, using deep-drawing or corresponding type of forming process. The influence of high-consistency refining, and combination of high and low consistency refining as well as the spraying of different biopolymers on the formability, strength properties and drying shrinkage of the samples has been evaluated in this work. By combining of the above-mentioned treatments it was possible to improve formability strain of the samples from 6.5% to 13.5%

In this patent and literary survey bioactive papers and fibre products, i.e. paper-like products, cardboard, fabrics and their combinations, etc., with active recognition and/or functional material capabilities are reviewed. The focus is on materials that specifically react with the target entity or environmental condition, and this reaction initializes different events, like a discharge of molecules or signalling function, in the product. The aim of this publication is to review and provide basic information on biomolecules and their potential utilisation for functional purposes, embedded signalling - concentrating especially on conducting polymers and optics - low-cost manufacturing on a large scale, modification of fibres and grafting or immobilisation of bioactive components. In addition, some application scenarios for bioactive paper products are presented.

In this patent and literary survey bioactive papers and fibre products, i.e. paper-like products, cardboard, fabrics and their combinations, etc., with active recognition and/or functional material capabilities are reviewed. The focus is on materials that specifically react with the target entity or environmental condition, and this reaction initializes different events, like a discharge of molecules or signalling function, in the product. The aim of this publication is to review and provide basic information on biomolecules and their potential utilisation for functional purposes, embedded signalling - concentrating especially on conducting polymers and optics - low-cost manufacturing on a large scale, modification of fibres and grafting or immobilisation of bioactive components. In addition, some application scenarios for bioactive paper products are presented.

Elintarvikepakkausmateriaalien turvallisuus ja mikrobiologinen puhtaus ovat erittäin ajankohtaisia aiheita. Suomen lainsäädäntö ja elintarviketeollisuus vaativat mm. elintarvikepakkausmateriaaleja ja elintarvikepakkauksia maahantuovilta, valmistavilta ja käsitteleviltä yrityksiltä toimivaa laatujärjestelmää elintarvikkeiden kanssa kosketukseen tarkoitettujen materiaalien turvallisuuden ja hygienian varmistamiseksi. Tässä julkaisussa käsitellään paperi- ja pakkausteollisuuden tuotteiden laatua ja laatujärjestelmiä sekä elintarvikkeiden kanssa kosketukseen tarkoitettujen pakkausmateriaalien lainsäädäntöä Suomessa. Julkaisussa keskitytään erityisesti omavalvonnan ja HACCP-järjestelmän (Hazard Analysis Critical Control Point) sisältöön ja toteutukseen sekä kyseisten järjestelmien aiheuttamiin muutoksiin eri yrityksissä. Julkaisun loppuosassa selvitetään elintarvikepakkausten hygieniariskejä, prosessihygienian hallintaa sekä käytännön kokemuksia ja tuloksia liittyen paperi- ja pakkausteollisuudessa tehtyihin HACCP-vaara-analyyseihin ja mikrobiologisiin hygieniakartoituksiin. Taustalla on laaja yhteistyö yritysten kanssa. Kaikkiaan kymmenelle tehtaalle on laadittu omavalvontasuunnitelma tai sen keskeisin kohta HACCP-vaara-analyysi. Laajoja mikrobiologisia hygieniakartoituksia on tehty useampaan otteeseen viidelle eri tehtaalle.

Elintarvikepakkausmateriaalien turvallisuus ja mikrobiologinen puhtaus ovat erittäin ajankohtaisia aiheita. Suomen lainsäädäntö ja elintarviketeollisuus vaativat mm. elintarvikepakkausmateriaaleja ja elintarvikepakkauksia maahantuovilta, valmistavilta ja käsitteleviltä yrityksiltä toimivaa laatujärjestelmää elintarvikkeiden kanssa kosketukseen tarkoitettujen materiaalien turvallisuuden ja hygienian varmistamiseksi. Tässä julkaisussa käsitellään paperi- ja pakkausteollisuuden tuotteiden laatua ja laatujärjestelmiä sekä elintarvikkeiden kanssa kosketukseen tarkoitettujen pakkausmateriaalien lainsäädäntöä Suomessa. Julkaisussa keskitytään erityisesti omavalvonnan ja HACCP-järjestelmän (Hazard Analysis Critical Control Point) sisältöön ja toteutukseen sekä kyseisten järjestelmien aiheuttamiin muutoksiin eri yrityksissä. Julkaisun loppuosassa selvitetään elintarvikepakkausten hygieniariskejä, prosessihygienian hallintaa sekä käytännön kokemuksia ja tuloksia liittyen paperi- ja pakkausteollisuudessa tehtyihin HACCP-vaara-analyyseihin ja mikrobiologisiin hygieniakartoituksiin. Taustalla on laaja yhteistyö yritysten kanssa. Kaikkiaan kymmenelle tehtaalle on laadittu omavalvontasuunnitelma tai sen keskeisin kohta HACCP-vaara-analyysi. Laajoja mikrobiologisia hygieniakartoituksia on tehty useampaan otteeseen viidelle eri tehtaalle.