Knowing the reflection, transmission, and absorption properties of the yarns from which the woven fabric is made, prediction of a fabric’s UV-protective properties is simple. Using the geometrical ...properties of monofilament yarns and fabrics, which were determined optically, and following the cover factor theory, we have determined the areas of fabrics covered with no yarns, only one yarn, and two yarns. From a special selected set of high-module polyethylene terephthalate (PET) monofilament materials (e.g., fabrics), we have elaborated a method for determining the reflection, transmission, and absorption of yarns. By first defining the differently covered areas of fabrics, we were able to use them in a mathematical model for calculating and predicting the UV-protective properties of the fabrics. The calculated and measured values of the UV-protective properties of the selected test fabrics were highly correlated, with a correlation coefficient >0.98.
The aim of this research was to prepare and analyze suitable microcapsules for the chosen end use—that is, bow-ties. The produced microcapsules were composed of melamine formaldehyde microcapsules ...with fragrance oils in the core. Regarding the properties, the surface morphology (studied by Scanning electron microscopy (SEM)), thermal properties (measured by Simultaneous Thermal Analysis STA), size and size distribution (by SEM and ImageJ software), and release behavior of the microcapsules were analyzed. The microcapsules were further (in two trials) applied with a screen-printing technique to textile materials which were investigated by microscopy (SEM) and tested for thickness, mass per unit area, and crease recovery angle. Finally, the scented bow-ties were designed and a subjective wear test was performed by the participants. According to the results, the prepared microcapsules were undamaged, with a spherical and smooth surface. An impermeable shell enabled the fragrance to be released simply by rupturing the microcapsules. This property was desired, since a stronger release through the permeable shell could be annoying for the wearer. During wear, the fragrance faded, but by rubbing the surface of the bow-tie and consequently rupturing the microcapsules, the release of the fragrance was initiated again, before or after wear.
The aim of our work was to establish whether very good to excellent UV (ultraviolet) protective properties of fabrics can be obtained through a suitable fabric construction and yarn colour, at the ...same time ensuring suitable air permeability.
For this purpose, six different fabric structures divided into three groups were employed. The samples were made in blue and red combinations of weft with different sequences and proportions between the upper and lower weave threads. A comparison of different fabric structures and colours was attempted to enable the assessment of the impact of the mentioned parameters on both, UV protective properties and air permeability of fabrics.
The analysis comprised the investigation of physical and permeability properties, as well as the colour measurements on twelve different cotton fabrics.
The research indicated excellent UV protection (>60) in all samples. UV protection depended on their construction and in a sufficiently closed structure, also on the colour of the used yarn. There was no significant difference between the samples in blue and red. In addition to excellent UV protection, four samples (one double-weft and three double fabrics) also demonstrated very high air permeability, which was 3–5 times higher than in the one-layer sample, which demonstrated the best UV protective properties.
The research has shown that fabrics with a very high ultraviolet protective factor value and good air permeability can be made by using a suitable construction and yarn colours that sufficiently absorb UV light; the latter being particularly important for light summer cotton clothes.
In the material extrusion of the thermoplastic filaments, known as Fused Deposition Modelling, usually, pure thermoplastic polymers are used. Recently, the focus of the research is given to the ...development of new biocomposite thermoplastic materials. In our research, 3D printable biocomposite filaments, made with the addition of 50 wt.% of cardboard dust to the HDPE and PLA polymer matrix were studied. The influence of the added cardboard dust on structural, morphological and mechanical properties of the 3D printable biocomposite filaments was investigated. With the addition of the corrugated cardboard dust into the HDPE and PLA polymer matrix the changes in density, uniformity, chemical structure and transition temperatures of the samples were detected. The addition of the cardboard dust into the HDPE polymer matrix lead to low tenacity, toughness, deformability resulting in brittleness of the 3D printable biocomposite filament, whereas the addition of the cardboard dust into the PLA polymer matrix lowered tensile properties, but didn't affected bending toughness and has even improved compression strength of the 3D printable filament.
The aim of this research was to analyze the influence of the solvents commonly used in flexography on photopolymer and ethylene propylene diene monomer (EPDM) flexographic printing plates and prints. ...EPDM plates are recommended when the reproduction process includes a higher amount of the solvents or aggressive solvents. Since additional UV treatment of flexographic printing plates could decrease the interaction between the plate and solvent, photopolymer and EPDM plates were treated with varied UV radiation and exposed to different types of solvents. Effects of the UV treatment and of the solvents on printing plate properties and on prints were analyzed. Results show that EPDM plates are more resistant to solvents in terms of the degree of swelling; however, surface properties of the plates were affected for both plate materials. In addition, the degree of swelling and increased hardness due to UV radiation were crucial for changes of the width of printed lines, and altered surface free energy affected the thickness of deposited ink film for both plate materials. Therefore, depending on the qualitative requirements of specific printed film, the duration of UV treatment can be adjusted for use with specific types of printing plate and solvent.
The process of oil-containing microcapsules production by complex coacervation of gelatine and gum arabic was patented in 1957. Microencapsulation technology gained importance in production of ...carbonless copy paper as one of the most important commercial products. Development of this technology in later years led to the emergence of different types of microcapsules and the production procedures for various application fields. Nowadays, they are mainly used in medicine, pharmacy, agriculture, construction industry, chemical industry, food industry, biotechnology, cosmetic industry, photography, electronics, textiles and printing industry. This review paper highlights the major types of microcapsules and their applications in production techniques in graphic arts and printing industry, various processing parameters that affect their important characteristics and methods for microcapsules characterization. This paper discusses the applications of microcapsules within printing industry, and feasible printing technologies related to the desired substrate materials. The analysis of these subjects offers a deeper insight into the mechanisms of microcapsule transfer processes, their behavior, and working conditions leading to the final products. It reveals the advantages and the drawbacks of certain printing technologies for microcapsules transfer, which enables the determination of favorable transfer procedure for specific microcapsule type and substrate materials. This paper also provides valuable recommendations and potential solutions on how to overcome the obstacles created by certain printing technologies.
The drying of microcapsules causes agglomeration and oversized agglomerates disturb fiber melt spinning. In this study, three parameters in co-current spray drying were studied and their influence on ...agglomeration was established with a morphological analysis, granulometric analysis, differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). The results showed that the inlet temperature, feed rate, and dry matter content have a significant influence on agglomeration; thus, their optimal combination was determined. In these conditions, the microcapsules were dried and applied in fibers.
The importance of protection against ultraviolet radiation (UV) is increasing daily. The dependence of the UV protection level on different clothes is determined by the shape and design of fabrics, ...and especially by their construction parameters. The fabric structure represents an important factor which is in most cases the only condition for good protection. Other possibilities to ensure good or even excellent protection, mainly by finishing treatments, can be efficient only if the fabric structure is closed enough. To determine the key parameters which contribute to the closeness of the structure and offer suitable UV protection, an analysis of monofilament woven fabric structure was made. Monofilament fabric samples used in the production of high-module screen-printing meshes, which are characterized by the excellent dimension stability of the structure, the properties of which change with varying diameters of the monofilaments and the fabric density, were chosen for this research. A broad spectrum of similar but structurally different fabrics assures referential samples are available for the evaluation of UV protection properties. In all the samples tested, the parameters of transmission and reflection were measured. Moreover, the values of absorption and the ultraviolet protection factor (UPF) were calculated. The values calculated on the basis of a determined mathematical model matched well with the measured values and they can together represent the basis for successful planning of fabrics with suitable UV protection properties.
The aim of the research was to establish whether addition on fragranced microcapsules influences on color values and perceptive properties of prints. For this purpose, three types of printing inks ...were used on two sets of the paper substrate. Color properties were measured by standard methods while perceptive properties were determined by subjective method. Research has shown that microcapsules cause small color differences while perceptive analyses gave very interesting results.
PDF
