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Tissue paper is a common type of paper material and is used in a variety of products. For tissue paper, several properties are of interest, such as absorbency, softness, bulk and mechanical properties. Embossing is an operation used to apply a pattern on tissue paper. It is used to improve several properties, but is known to reduce mechanical properties. Currently, no models can predict the loss of strength due to embossing. In this report base tissue paper is embossed with two different embossing patterns and tensile tests are conducted with and without edge notches. The edge notch length was varied between 0 mm to 12 mm. From the experiment, a modified Linear Elastic Fracture Mechanics model was applied on both base tissue paper and embossed tissue paper tensile test results. The experimental procedure is described. In total, four different paper qualities were tested. Two that are designed for toilet paper and two that are designed for kitchen paper. The tissue sheets were embossed using 3D-printed plates and conducted in a laboratory environment. Tensile tests with edge-notch specimens were performed. The notch lengths tested were between 0 mm and 12 mm long. It was investigated if any trends of the parameters in the model could be noticed due to embossing. The model worked well for all base tissue qualities. The embossing reduces the material's tensile strength compared to the base material. With increasing embossing load, longer notches are needed to drop the tensile strength of the specimen. Some general trends were noted. However, the impact of the embossing was different for different paper qualities and the embossing pattern used. The most significant difference between plates was noted in specimens with high embossing load. With increasing embossing load, the edge-notch must also be longer to reduce tensile strength. The model parameters changed more for machine direction (MD) specimens than crossmachine direction (CD) specimens., Mjukpapper är en vanlig typ av paper som används bland annat till toalettpapper och hushållspapper. För mjukpapper finns det flera egenskaper som är viktiga för en bra produkt. Hur bra mjukpapperet kan absorbera vätska, hur mjuk det är för användaren samt mekaniska egenskaper så som drag styrka. Prägling är en operation som görs på mjukpapper för att förbättra egenskaper, till exempel mjukhet, men på bekostnad av mekaniska egenskaper. För tillfället finns det inga modeller som kan förutse förlusten i styrka på grund av präglingen. I den här rapporten beskrivs processen för att prägla mjukpapper med två olika präglings mönster i ett laboratorium klimat. Fyra olika mjukpappers kvalitéer präglades. Dragprov genomfördes på det präglade proverna med och utan kantspricka. Kantsprickans längd var som längst 12 mm. Från dragprovs resultaten tillämpades en modifierad linjärt elastisk brottmekanisk modell. Modellen fungerade bra för både icke präglat och präglat mjukpapper Parametrarna för modellen ändrades för präglade provbitar jämfört med icke präglade. Inverkan av prägling påverkades både av mjukpapperet sort och präglings mönstret som användes. Störst skillnad mellan präglingsmönster sågs vid hårt präglade provbitar. Präglade provbitar behövde längre kantsprickor för att förlora dragstyrka.

Tissue paper is a type of soft, absorbent, and lightweight paper with several applications for hygiene and kitchen use. Embossing is an operation during the converting stage of the tissue production process which creates relief designs on tissue. Other than producing designs for aesthetic purposes, embossing increases bulk which improves absorbency and softness but reduces mechanical strength and stiffness. A computational model using the finite element method is developed to simulate the embossing of tissue paper. A tool for fitting an appropriate material model for tissue to its experimental test data is implemented. The material model is subjected to a verification test and it works sufficiently well to model the in-plane elastic and plastic anisotropic behavior of tissue. Two validation tests are conducted to check the embossing model against experimental test data where it is observed that the model works well. Firstly, it provides an idea about the amount of pressure required to be applied during loading to reach a certain embossing level. Secondly, it predicts the tensile strength of embossed tissue sheets although it provides a slight underestimate. Potential reasons for the shortcomings in the tensile strength are suggested and recommendations for further improving the model are provided. Lastly, parametric studies are conducted to investigate the influence of embossing pattern geometry on the mechanical performance of embossed tissue. After passing the verification and validation stages, the model is ready to serve as a convenient, less time-consuming, and cost-effective alternative to experimental testing to study the embossing process. It can also be used as a tool to examine the effect of one or more model parameters on embossing by simply changing them and studying the new results., Mjukpapper är ett mjukt och absorberande papper med låg ytvikt för hygien- och köksändamål. Prägling är en operation under konverteringsstadiet av produktionsprocessen som skapar reliefmönster på mjukpapperet. Förutom att skapa mönster för estetiska ändamål, ökar präglingen bulken som förbättrar absorptionskapacitet och mjukhet men den minskar mekanisk styrka och styvhet.En beräkningsmodell med finita element-metoden utvecklas för att simulera prägling av mjukpapper och ett verktyg för att koppla en lämplig materialmodell för mjukpapper till dess experimentella testdata implementeras. Materialmodellen genomgår ett verifieringstest och det fungerar tillräckligt bra för att modellera det elastisk-plastiska anisotropiska beteendet hos mjukpapper i planet. Två valideringstester utförs för att kontrollera präglingsmodellen mot experimentella testdata där det observeras att modellen fungerar bra. För det första ger den en uppfattning om mängden tryck som behöver appliceras för att nå en viss präglingsnivå. För det andra förutspår den draghållfastheten hos präglade mjukpappersark även om det ger en liten underskattning. Potentiella orsaker för bristerna i draghållfasthet föreslås och rekommendationer för ytterligare förbättringar av modellen ges. Slutligen genomförs parametriska studier för att undersöka påverkan av präglingsmönstergeometri på den mekaniska prestandan hos präglat mjukpapper. Efter att ha klarat verifierings- och valideringsstegen är modellen redo att fungera som ett lätthanterligt, mindre tidskrävande och mer kostnadseffektivt alternativ till experimentell testning för att studera präglingsprocessen. Det kan också användas som ett verktyg för att undersöka effekten av en eller flera modellparametrar på prägling genom att helt enkelt ändra dem och studera de nya resultaten.

Small-scale optical components with micron or submicron features have grown in popularity in recent years. High-quality, high-efficient, and cost-effective processing approaches for polymer optics mass production are an urgent need. In this study, ultrasonic vibration will be introduced in embossing. The major advantage is that the required energy can be provided for process times ranging from a few hundred milliseconds to a few seconds, and that the process energy is provided at exactly the required location so that the structures in the surrounding area are not affected. Due to the strong correlation between electrical impedance and the temperature of the material, a novel impedance-based control strategy has been utilized for precisely controlling ultrasonic vibration during the embossing process. The investigation used two types of stamps with grating line widths of 4 µm and 500 nm, respectively. As a result, an embossing time of less than a few seconds was accomplished and a uniform embossed surface with an average fill rate of more than 75% could be achieved.

Structuring of semiconductor materials is utilized in many optoelectronic devices, e.g, in order to make them more efficient, cost-effective, and/or to obtain specific wavelength-engineered responses. Semiconductor materials are widely used in optoelectronic devices due to their favorable optical and electric properties. Surface structuring of semiconductor materials can be applied in order to functionalize the surface by providing specific light manipulation functions (e.g., anti-reflection, trapping, scattering, and/or mode coupling). Thereby, light-matter interactions can be realized that are tuned for specific optoelectronic applications. The choice of materials, geometry, and spacing of the surface structuring are important factors. This thesis work investigates the nanostructuring of several types of semiconductor materials (e.g., c-Si, a-Si, GaInP, TiO2, and ZnO) for applications such as optical sensing, broadband anti-reflection, light extraction enhancement, optical/color filtering, and color conversion. c-Si nanopillar arrays are used as a platform for optical sensing. Their characteristic reflectance spectrum is used, where a peak shift of the reflectance spectrum is related to the refractive index and thickness of a deposited layer. A fabrication process based on nanoimprint lithography and inductively coupled plasma reactive ion etching was used to fabricate Si nanopillar arrays. Refractive index sensing applications were investigated by measurements and simulation study. Both medium sensing and surface sensing applications were demonstrated. The medium sensing resulted in a refractive index sensitivity of ~250 nm/RIU within the visible(-NIR) wavelength spectrum and a lower bound detection limit of ~2∙10-4 RIU-1. The surface sensing enables to measure lower bound (average) SiO2 and Si3N4 layer thicknesses of ~8.1∙10-2 and ~5.2∙10-2 nm, respectively, which is less than a monolayer of these materials. a-Si nanodisk arrays are demonstrated for broadb, Strukturering av halvledarmaterial har många användningar inom optoelektroniska komponenter, t.ex. för att göra dem mer effektiva, kostnadseffektiva, och/eller för att uppnå våglängdsspecifika funktioner. Halvledarmaterial används ofta för optoelektroniska komponenter på grund av deras goda optiska och elektriska egenskaper. Ytstrukturering av halvledarmaterial kan användas till att funktionalisera ytan med egenskaper för att manipulera ljus (t.ex. antireflexion, infångning, spridning och/eller mode-koppling). Därigenom kan interaktioner mellan ljus och materia kontrolleras för specifika optoelektroniska ändamål. Valet av material, geometri och period hos ytstrukturerna är viktiga faktorer. Arbetet som presenteras i den här tesen undersöker nanostrukturering av flera olika halvledarmaterial (t.ex. c-Si, a-Si, GaInP, TiO2 och ZnO) för applikationer inom optiska sensorer, hög bandbredds antireflexion, ökning av ljusextraktion, färgfiltrering och färgkonvertering. Fält av c-Si nanopelare används som en plattform för optiska sensorer. Deras karakteristiska reflexionsspektrum används, där ett skifte i positionen hos en reflexionstopp är relaterat till brytningsindexen och tjockleken på ett deponerat lager. En tillverkningsmetod baserad på ’nanoimprint lithography’ och reaktiv jonetsning med induktivt kopplat plasma användes för att tillverka fält av Si nanopelare. Brytningsindex detektion undersöktes med experiment och simulering. För brytningsindex detektion demonstrerades detektion av både ändring i index för ett omkringliggande medium och för tunna lager på ytan av pelarna. Medium avläsningen gav en brytningsindexsensitivitet på ~250 nm/RIU inom det synliga ljusspektrumet och en lägsta detektionsgräns på ~2∙10-4 RIU-1. Detektion på ytan möjliggör mätning av lagertjocklekar av SiO2 och Si3N4 på ner till ~8.1∙10-2 och ~5.2∙10-2 nm, respektive, mindre än ett monolager av dessa material. Fält av a-Si nanodiskar demonstreras för antireflexion med hög bandbredd och, The PhD defence will be Zoom-based. Only key-persons will be present at the defence location and the other attendees participate via Zoom.

Microneedle arrays have been proposed for drug delivery and point-of-care diagnostics to improve the quality of health care delivery systems. Unskilled and painless applications of microneedle patches for blood collection or drug delivery are two of the advantages of microneedle arrays over hypodermic needles. Microneedle designs which range from sub-micron to millimetres feature sizes are fabricated using the tools of the microelectronics industry from materials such as metals, silicon, and polymers. However, to date, large-scale manufacture of microneedles has been limited because of the high cost and complexity of microfabrication techniques. This thesis aims to develop new manufacturing methods that may overcome the complexity of microneedle fabrication and scale-up problems. Two different microfabrication methods were investigated. (1) Silicon microneedles were manufactured through deep reactive ion etching (DRIE) with variable heights and tip sharpness. A series of experiments were also performed to investigate the influence of design and process parameters on the fabrication outcomes. (2) A great variety of microneedle array geometries were manufactured using 3D laser lithography as a rapid prototyping technique was required for different microneedle geometries. These microstructures were successfully replicated by soft embossing. Furthermore, the mechanical stability of microneedles were analysed by compression tests and finite element analysis (FEA). The data was used to quantitatively define the microneedles fracture force and skin penetration capabilities. A novel microneedle device for subcutaneous fluid sampling and drug delivery was easily manufactured by 3D laser lithography and soft embossing; fluid was drawn into each microneedle and microwell reservoir by capillary pressure via open channels that draw fluid along the side of microneedle shafts into microwell reservoirs. Time-lapse microscopy showed that microwells fill rapidly by capillary pressure

We present a simple and flexible mechanical approach for 2D micropatterning of multiple cell lines without surface modification. The principle is that during initial attachment cells only stick to unoccupied areas; we create such areas to selectively seed a subsequent cell line by using a stamp to erase previously attached cells at designed areas. By repeating this process, multiple types of cells were patterned on a single substrate. This strategy minimizes the disturbance to cell health, which might be a concern in printing-based patterning. Micropatterns of cells with resolution of approximate to 50 mu m, and a co-culture of three cell types were easily achieved and studied. This method was found universal to at least MSC, HeLa, HepG2 and NIH 3T3. We also measured the invasion and cell growth under the co-culture of HeLa, MSC and HepG2. This method is useful for studying cell-cell interaction in high-throughput, free of the potential bias caused by selective surface modification in some previous methods.

This master thesis has its main focus within embossing operations and how different factors influence the result. The work was performed at Stora Enso Research Centre in Karlstad, Sweden. Embossing is relatively complex operation to analyze since the paperboard can be exposed of both bending, shear and compression at the same time. The techniques used today for evaluating embossing on paperboard consist of experimental setups. These experimental techniques needed to be complemented in order to simplify the approach for embossing evaluations. The aim of this thesis was to develop a simulation material model, created with Finite Element Method by using Abaqus (2014), which capture the experimental behavior of embossed paperboard. The goals were to understand which material properties that are of high importance in embossing operations, and how sensitive the simulation material model is at small geometry changes of the embossing tool. A three dimensional finite element material model has been created in Abaqus (2014). The analysis was performed as dynamic quasi-static where an implicit solver was used. The simulation material model consisted of a continuum model, which describes the behavior of the plies, and an interface model implemented as cohesive elements, which describes the inelastic delamination between the plies. The continuum model was defined as an anisotropic linear elastic-plastic material model with isotropic linear hardening together with Hill´s yield criterion. The interface model was defined with an anisotropic elastic-plastic traction-separation law and an exponential damage evolution model. The purpose of the experimental tests was to capture the behavior of embossed paperboard and the goal was then to recreate the behavior in the simulation model. The results in this thesis focus on the relationship between the applied force and the displacement. An experimental and numerical study of out-of-plane compression has also been conducted, where the aim w

В статье рассмотрены основные технологические факторы, влияющие на качество тиснения полиграфической фольгой, и приведены сведения об оптимальных режимах (давление, температура штампа и т. д.) тиснения фольгой на переплетные материалы, о влиянии различных параметров на качество тиснения. Тиснение фольгой, благодаря своим широким изобразительным возможностям, является самым распространенным видом тиснения и всегда осуществляется при помощи горячего клише. Фольга от температуры оплавляется и оставляет на поверхности металлический оттиск. Сегодняшний ассортимент полиграфической фольги позволяет реализовать самые смелые решения, что актуально в использовании разнообразной полиграфической продукции не только в брошюровочно-переплетных процессах, а также в сфере дизайна, включая изделия от упаковок до открыток., This article describes the main technological factors affecting on the quality of the printing foil stamping and provides information on optimal conditions (pressure, temperature, stamps, etc.) of foil stamping on bookbinding materials and about influence of various parameters on the quality of stamping. Foil stamping, due to its wide visual capabilities, is the most common type of embossing and it always carried out with hot cliché using. Foil temperature melts and leaves on the surface of a metal stamp. Today’s range of printing foil allows to realize the most daring design decisions, that is actual in the use of various printed products not only in book-binding processes, and also in the field of design, including different products such as the packages and cards.

In this study, the tensile test of the embossed sheet was conducted and the tensile deformation behavior is experimentally investigated. Also, in this study, the finite-element method (FEM) analysis on tensile deformation of sheet metals embossed on both side of the plane was also carried out. Fundamental tensile deformation behavior of the embossed sheet was investigated and the relationships between deformation mechanism and apparent mechanical properties are considered.

In this study, an impinging jet deposition experiments were performed on synthetic polymer (Zeonor) original and by micro-embossing modified substrates with exactly defined topology as confirmed by AFM and SEM. Deposition experiments were performed at ambient temperature and at selected flow regime of Re = 10. As a particles deposited a polystyrene (PS) 1,1 μm diameter particles (Sigma-Aldrich) were used having negative charge of -20 mV as observed by zeta potential experiments. There was found gradual increase of total number of deposited particles with time reaching steady state number. Obtained kinetic curves were fitted to the theoretical blocking model where characteristic time required to reach the steady state (blocking time) as well as steady state number of deposited particles were calculated. © 2014 Elsevier Ltd. All rights reserved.

Biopolymer films with a thickness of 100μm are prepared using spin coating technique with solutions consisting of 25wt.% polycaprolactone or poly-l-lactide in dichloromethane. SU-8 stamps are fabricated using three photolithography steps. The stamps are used to emboss 3D microstructures in the biopolymer films. It is found that the best pattern transfer for the polycaprolactone films is achieved just below the melting point at 60°C. For the poly-l-lactide films the best pattern transfer is achieved at 120°C.

Cílem této bakalářské práce je shrnutí veškerých dostupných informací, které se týkají zhotovení a kvality slepeckého písma. Na základě informací vyhledaných v odborné literatuře, vědeckých časopisech a informací získaných od firem, zabývajících se aplikací slepeckého písma, byl vypracován přehled nejdůležitějších poznatků. Pozornost byla zaměřena především na to, jak jednotlivé techniky a použité materiály ovlivňují výslednou kvalitu slepeckého písma, jako je výška bodů, jejich tvar a čitelnost., The aim of this bachelor thesis is to sum up all available information about manufacture and quality of Braille. It was worked out the summary of the most important facts about Braille. This summary was based on information, that were studied in technical literature, scientific journals and company´s brochures. The main part of this thesis was focused on different techniques and materials that influence the final Braille´s quality, such as height, form and readability of Braille´s points., Katedra polygrafie a fotofyziky, Ing. Bohumil Jašúrek, Ph.D. - Jaká je minimální výška Braillova písma, která se dá bez komplikací číst? Ing. Jan Vališ, Ph.D. - Proč je vynechán na vzorcích lak?

Cílem této práce je shrnutí veškerých dostupných informací, týkajících se problematiky aplikace Braillova písma, The objective of this thesis is a summary of all available information concerning the problems of application of Braille., Katedra polygrafie a fotofyziky, prof. RNDr. Marie Kaplanová, CSc. - Nebylo možné provést zkoušky na komerčním zařízení? doc. Ing. Michal Veselý, CSc. - Jaký byl úbytek vrstvy po různých počtech oděrových taktů? Co polymeruje v termografickém prášku? ing. Tomáš Syrový, Ph.D. - Jak jste zjistila úbytky vrstvy? doc. Ing. Petr Němec, Ph.D. - Z jakého důvodu dochází ke změně objemu vrstvy prášku? ing. Bohumil Jašúrek, Ph.D. - Je doporučená nějaká optimální výška Braillova písma?, Dokončená práce s úspěšnou obhajobou

This thesis comprises tribological studies of extremely well-defined surfaces of different designs. Both low-friction and high-friction surfaces were manufactured and experimentally evaluated. In the low-friction studies, lithography and anisotropic etching of silicon was first used as a texturing technique. The textured surfaces were subsequently PVD coated with TiN or DLC to achieve tribologically relevant interfaces. The results showed that under starved lubricated conditions, fine surface textures lowered the coefficient of friction and the wear rate. It was shown that also the orientation of the texture is of major importance for the lubricating function. Further, a novel embossing technique was developed, permitting texturing of steel and other materials. A micro mechanically designed diamond tool was used to emboss steel surfaces. The roller/piston contact from a hydraulic motor was simulated and introduction of an embossed texture on the piston decreased the level and the fluctuation of the friction. The effect of the texture was here similar to the effect of an additional polish step. However, in general it is not an easy task to substantially improve a boundary lubricated contact by introducing a texture. Studies of high friction surfaces were performed on micro mechanically designed diamond surfaces equipped with sharp pyramids or ridges. Just as theory predicts, the coefficient of friction was dependent on the shape of the ploughing bodies, but not on the counter material or the load. The tested surfaces resulted in static coefficients of friction between 1.1 and 1.6, depending on surface design and orientation. These are extremely high values, and therefore very interesting for practical applications requiring a high static friction. Conclusively, the present thesis shows that it is possible to design and produce surfaces both for improved lubrication in sliding contact and for substantially improved high friction performance in static contacts.

This report documents an approach to fabricating large area, low cost 3-D photonic crystal structures using continuously web compatible techniques. We document and detail a process that involves microembossing, differential stripping, direct transfer, and alignment. We also discuss an analytical technique that can be used to model the reflectance and transmittance of multilayer structures. The principle goal of SAIC's Highly Controlled Dielectric Emissivity (HIDE) program was to apply the techniques of large area, low cost, continuous web manufacturing to fabricate photonic band gap structures that exhibit finite width pass- and stop-band properties in the 8-12 micrometers wavelength regime.

The patent relates to a cup-shaped blank extruded through a die onto a cylindrical non-collapsible mandrel having an external surface pattern counter to a desired internal embossment. Subsequently, the embossed portion of the blank is hydrostatically expanded away from the mandrel to permit removal of the embossed part from the mandrel. The application of hydrostatic pressure to the exterior of the blank during the extruding operation is disclosed.

The feasibility of holographically storing and retrieving aerial chart information for display in a cockpit environment has been demonstrated during two sequential exploratory development programs, leading to the development of a laboratory model for a full color holographic moving map display system. The work done on this contract had as its primary goal the definition and consideration of the holographic recording process, and in particular the methods of generating the color separations required for full color recording, methods of registering the separations during recording, definition of the exposure levels and latitudes allowable during exposure, and methods of refining the duplication process for use in a non-laboratory environment. (Author)