Search

All woven fabric surfaces consist of various types of imperfections and irregularities that are affected by the construction characteristics of the fabric, mostly weave and yarn fineness. Tactile property is a multidimensional concept consisting of several characteristics, among which is surface roughness, as the fundamental and most effective factor whose parameters along with the parameters of surface waviness describe the topographic woven fabric properties. Fabric topography is expressed by periodic repetition of waves in the vertical and horizontal directions caused by its structure. Surface roughness is the totality of microgeometric irregularities on the fabric surface and has a significant role in the final use of fabrics, especially in ones that are in contact with human skin. In order to establish the connection between fabric construction parameters and their roughness, it is sufficient to describe its surface properties at the meso level. For the purpose of this research, woven fabric with complex weave construction (layer interchanging double cloth) was designed, using different raw material fibers (AR - 95% Meta Aramid Conex NEO ; 5% Para Aramid Twaron raw and MAC/CO - 45% Cotton Long Stapel Combed, 55% Modacrylic Sevel FRSA/L), which will provide a diversity of structure and thus various properties on the front and backside of the fabric. For this reason, an investigation on the properties of roughness has been conducted on the backside of woven fabrics, where MAC/CO yarn predominates with the purpose to obtain fabric comfort when in contact with the skin. Figure 1 shows a correlation between the average amplitude from the roughness profile with yarn fineness and fabric density. The mean amplitude of roughness profile, in weft, direction decreases with increasing yarn fineness in weft in the first three samples where the differences in weft density are negligible. The sample with the finest weft (Sample 4, 12.5x2 tex) has higher values of mean amplitude in weft, which is caused by the increased weft density (66 threads/cm), while the other samples had a slight difference in weft density (58 threads/cm). Regarding the mean amplitude for warp, whose density is the same for all samples, the values decrease nonlinearly with increasing weft fineness. Statistical analysis confirmed that weft fineness has the greatest influence on the average wavelength and amplitude of the roughness profile (both R2 = 0.91), in warp direction.

The surface roughness affects the aesthetic properties of the woven fabric and plays a significant role in the final use of the fabrics. There are two reasons for measuring the same, namely: to control production as much as possible (special finishes) and to ensure good product performance. The surface roughness is important for fabrics that are in contact with human skin. The influence of the maintenance process on the topographic structure of cotton/polyester fabrics has been examined in this paper. Samples of different weaves were examined and the density of warp and weft, crimp and the thickness of the fabric were measured. Also, the parameters of the fabric topographic structure, roughness and waviness were determined. A total of 18 samples were tested in 6 stages of textile care (washing), and changes in parameters were monitored after each stage. Test results showed that the surface roughness parameter decreased in all samples with the rise of the number of washing cycles. On the other hand, the waviness parameter did not change drastically except for samples in plain weave where continuous growth was recorded

In everyday use, textiles are exposed to abrasion, e.g. when worn (textiles to textiles friction, skin on textiles, various objects in textiles) and during the maintenance process (washing). Constant friction results in a decrease of the textile material strength which impairs both appearance and functionality. The abrasion resistance of woven fabrics is influenced by its structural and constructional characteristics, raw materials and finishing processes.

Yarn abrasion resistance is a significant property for the quality of the woven fabric production process. In the weaving process, the yarn passes through various metal elements on the loom, in a state of high tension and continuous cyclic stresses. The geometry of the staple yarn can be described as an elongated cylindrical shape of a very relief and rough surface conditioned by the number of twists and yarn hairiness (protruding fibre ends). Such structure, under conditions of high cyclic stresses, is subject to various deformations depending on the properties of the yarn itself. There are large number of various methods for determining the yarn abrasion resistance that are based solely on the number of cycles to yarn break. However, none of them provides insight into the structural changes that occur during the abrasion process, while the breakage has not yet occurred. Such changes remain unregistered by standard yarn abrasion resistance methods but have a large impact on the quality of the produced woven fabric. In this paper, the influence of yarns structural characteristics on their behaviour due to abrasion process was investigated. Seven yarn samples (four single and three plied yarns from a polyamide and cotton fibres blend, of fineness: 50, 38.5, 29.5, 20, 15.5x2, 14x2 and 10x2 tex) were tested. Fineness and twist number, as well as unevenness and hairiness were tested on all samples. All yarns are subjected to abrasion cycles on a yarn abrasion device according to standard FZ/T 01058- 1999, „Reciprocating rubbing roller method “. Prior to abrasion was conducted and after 20, 50, 100, 500, 1000, 2000 and 3000 cycles, a microscopic image of five labelled yarns was taken for each sample. Later, the image analysis was conducted where the average diameter of each yarn sample was calculated. The number of cycles at the yarn break was also recorded and the basic statistical parameters were calculated. The results showed that single yarns behave completely differently from plied yarns when subjected to abrasion. In the case of single yarns, the velocity of diameter change is significant in relation to the plied ones. Furthermore, fineness significantly affects the velocity of diameter change (decrease), where the coarser yarn wears faster and consequently the diameter decreases faster. The reason for this may be a higher proportion of longer fibres and a higher number of twists in yarns of greater fineness compared to coarser ones. In the case of plied yarns, there is practically no change in diameter with increasing abrasion cycles number. The behaviour of the plied yarns can be described as the apparent destruction of the structure due to abrasion, where the fibres are no longer parallel to each other but remain within the yarn where the relative diameter of the yarn does not change or is visually even increased. As for yarn breakage due to abrasion, coarser plied yarns withstand more abrasion cycles. As the fineness of the yarn increases and in a case of plied yarn, the abrasion resistance of yarn increases.

U današnje vrijeme sve je zahtjevnije i složenije postići određena svojstva tkanina ili kompozita, koja propisuju norme za određenu namjenu, a još je teže postići održivost tih svojstava tijekom uporabe. Tkanine koje se odlikuju svojstvima smanjene gorivosti, pored osiguranja visoke razine zaštite, moraju posjedovati i svojstva udobnosti, trajnosti i postojanosti. Jednoslojne zaštitne tehničke tkanine s površinskom obradom, trenutno dostupne na globalnom tržištu u segmentu tkanina smanjene gorivosti, imaju nedostatak integriranosti krucijalnih svojstava, između kojih i udobnosti tijekom dužeg nošenja, zbog čega pružaju osjećaj zatvorenosti tijela u „kalup“. Odabirom vlakana odgovarajućih svojstava i optimizacijom njihovog udjela u konačnoj tkanini, razvojem novih tkanih struktura te kombinacijom s drugim relevantnim konstrukcijskim parametrima, projektirat će se i izraditi inovativne tkanine ciljanih svojstava, s obzirom na krajnju namjenu. Zaštitna svojstva novo razvijenih tkanina bazirat će se prvenstveno inkorporiranjem svih utjecajnih parametara te kombinacijama jednoslojnih, ali i višeslojnih provezujućih tkanina, sirovina, finoća pređe i gustoća tkanine. Gornja tkanina koja čini lice imat će snažna svojstva zaštite, dok će tkanina na naličju biti lagana, ugodnog opipa i prozračne strukture te će cjelokupna tkanina svojim konačnim karakteristikama osigurati udobnost, trajnost, postojanost i u konačnici multifunkcionalnost. Istraživanja multifunkcionalnih tkanina smanjene gorivosti, kako u segmentu tehnološkog procesa projektiranja i izrade, tako i u segmentu doradnih procesa, predstavljaju značajan tehnološki iskorak, a novo razvijene tkanine odlikovati će se inovativnošću, jedinstvenošću i konkurentnošću.

The complex structure of fabrics makes it a heterogeneous flat material in which the air volume units between the warp and weft threads make the material porous. The fabric porosity indicates the proportion of pores in the fabric, which together with other fabric structural parameters affect the transmission property. The transmission of light radiation through the fabric is an important parameter in the development of fabrics for certain purposes. This research will determine the influence of different fabric structural parameters on light transmission and highlight its advantages regarding the application and purpose of the fabric itself.

Previously conducted research as well as determination of development segment in the form of improvement of woven fabrics currently available on the global market of technical textiles, represents the basis for future extensive research of design and manufacture of multifunctional non-flammable woven fabric, which will be conducted within the project "Development of multifunctional non-flammable woven fabrics for dual purpose". The goal is to design the fabric (maintaining the existing protective and tensile properties, but also to improve it by optimizing the structural and constructional parameters) which will optimally meet the requirements of the global market and combine the characteristics of non-flammability (protection against heat), comfort, breathability, resistance and durability.

In order to meet the high requirements set for the properties of woven fabrics for protective clothing, fabric lamination or fabric layering (composites in which the woven fabric is one of the elements) is performed. Processes of fabric surface finishing or layering, at the same time negatively affect the final product, making it thicker, stiffer, impermeable, unbreathable and thus extremely uncomfortable and finally unacceptable for the production of the entire protective clothes. For the purpose of this research, a woven fabric with complex construction was designed, using complex weave, different raw material fibres with integrated protection properties and combination with other relevant structural parameters, which will provide diversity of structure and thus properties on the front and backside of the fabric. The acceptability of the produced fabrics for the end use application were analysed by subjecting it to testing methods of heat, thermal and water-vapour resistance. From all the above, it can be concluded that the design of new construction solutions, which can influence the fulfilment of a wide range of requirements in order to achieve multi- functional multi-layer fabrics, is justified.

This paper investigates newly developed synthesized corn starch for the sizing process, as an environmentally-friendly product used for cotton yarn sizing. The development of such newly synthesized natural starch led to a decrease in its molar mass, which made it easier to dissolve and thus easier to penetrate into the yarn structure and subsequently easier to remove from the fabric. Acrylamide (AA) and 2-hydroxyethyl methacrylate (HEMA) were used as monomers in the corn starch grafting process. The same initiators were used for the more efficient formation of grafted monomers on starch: azobisisobutyronitrile (AIBN), potassium persulfate (KPS) and benzoyl peroxide (BP). Research results and FTIR analysis showed that efficient new synthesized corn starch was obtained. The justification of usage of synthesized corn starch was confirmed, especially initiator AIBN in grafting process with 2-hydroxyethyl methacrylate (HEMA) on starch. Analysis of sized yarns found that coarser single as well as plied yarns adsorb or bind more sizing agents in all cases than finer yarns, which can be explained by a larger capacity in volume, looser structure and a smaller number of twist. After sizing process, the mechanical properties of the yarn changes, the breaking force increases, while the breaking elongation partially decreases. The micrographs of the yarns treated with the new starch have a more compact structure with fibres glued together, as well as great parallelism in the direction of the yarn longitudinal axis. Careful choice of the active agent synthesis process, a valid combination and optimal choice of temperature-time regime, can ensure the proper composition of sizing mass and processing method, which will ensure a high quality and uniform yarn sizing process. Based on the extensive conducted analyses, it can be concluded that there is a qualitative and environmental cost-effectiveness using the synthesized potato starch.

Sveučilišni udžbenik Tehničke tkanine namijenjen je prvenstveno studentima Tekstilno- tehnološkog fakulteta kao obvezna literatura na istoimenom kolegiju, koji doprinosi stjecanju širih znanja i kompetencija studenata modula Projektiranje i menadžment tekstila. Ovaj je udžbenik korisna literatura i za druge kolegije na Fakultetu gdje se tehničke tkanine obrađuju samo u jednom dijelu programa. Isto tako, sadrži korisne informacije za stručnjake u industriji i drugim institucijama u Republici Hrvatskoj i šire. Udžbenik je namijenjen i znanstvenicima, inženjerima koji se bave ili rade u proizvodnji ili istraživanjima tehničkih tkanina. Zbog složenosti strukture, njihove velike rasprostranjenosti i različitosti, tehničke tkanine obradit će se po skupinama primjene, odnosno prema podjeli tehničkih tkanina. Dat će se velika važnost vlaknima i pređama koje se koriste za tehničke tkanine, njihova bitna svojstva i namjena u tehničkim tkaninama. Obradit će se, osim klasičnog načina tkanja i specifične izrade, kao provezujuće, šuplje, 3D i pametne tkanine. Budući da su tehničke tkanine iznimno rasprostranjene, različite u strukturi, namjeni i izradi, i tkalački se strojevi bitno razlikuju. Stoga su posebno obrađeni tkalački strojevi i to za: tkanje sukljanih tkanina, višeosnih, kružnih, frotir, te pliš/samt/baršun/velur tkanina, potom tkanje šupljih, provezujućih, 3D i ekstremno širokih tkanina, te ostali tkalački strojevi koji se razlikuju od klasičnih po svojoj specifičnosti, kao za tkanje: tkanje vrpci, zavoja, krvnih žila i sl. Jedan dio strojeva i procesa tkanja moguće je, prema literaturi, pratiti na mrežnim stranicama koje upućuju na najnovija dostignuća. U sadržaj udžbenika unijete su i najvažnije ISO norme, trgovački nazivi i opisi tkanina po skupinama. Tehničke tkanine zauzimaju važno mjesto u proizvodnji tkanina u Republici Hrvatskoj. Tkaonice koje su opstale nakon Domovinskog rata, danas većinom proizvode tehničke tkanine koje su spomenute i u ovom udžbeniku. Ovaj udžbenik nastao je i s tom motivacijom, kao spona između tekstilne industrije i znanstvene institucije Sveučilišta u Zagrebu Tekstilno- tehnološkog fakulteta. Također, obrađuje tehničke tkanine na trenutačnoj razini s dosadašnjim razvojem i primjenom. Daljnjim razvojem novih tehnologija i materijala, te unapređenjem ove skupine tkanina, njihova namjena postaje sve šira i važnija. U cilju poboljšanja postojećih tehničkih tkanina i pronalaska novih primjena, potrebne su mnoge inovacije, ali i saznanja o dosadašnjim razinama razvoja i primjene. To nas obvezuje da se ovaj udžbenik dalje nadopunjuje najnovijim dostignućima u razvoju i primjeni.

Yarn sizing represents the most complex phase in the fabric production, due to the necessary multidisciplinary approach to the whole process, with the aim of achieving improvement in the yarn physical-mechanical parameters relevant for the further weaving process. Changes of the sizing parameters, of both, the sizing plant and the sizing conditions, greatly influence the sized yarn properties. This research deals with type of yarn (PA 6.6 / cotton) that are characterized by their abrasion resistance but at the same time by their durability, comfort, lightweight and strength. Despite these remarkable properties, subjecting these yarns to the sizing process enhance their properties relevant for further technological processes of fabrication in order to achieve maximum effects. This research shows the extent to which the sizing process influences the improvement of tested yarns properties and analyse the impact of various size mass concentrations and different sizing processes. The complete analysis is considered in the context of sizing process optimization and overall justification and acceptability.

Woven fabric as a complex structured orthotropic material has two axes of symmetry: in the warp and weft direction. In the ideal case of symmetrical woven fabric (in plain weave and in its derivatives) orthotropic main axis lay on the axis of structural principal directions of the fabric, but in the case of asymmetric woven fabric - geometrical diagonally structured woven fabric (in twill and satin weave and in their derivatives) at normal stress, axis displacement i.e. angular deformation occurs. This phenomenon is not the result of shear stress, but rotation of orthotropic main axis with regard to the axis of structural principal directions of the fabric. With this research, the knowledge about the behaviour of asymmetric woven fabrics at normal stress will be expanded, which will lead to insights about important material properties that will define its qualitative and use values in the field of small and large surface axial stress.

Weaving of table linens (table covers, decorative tablecloths and napkins) on large width weaving machines in a form of multiple tapes, weft cutting and selvedge forming on the edge of tapes are common and effective way of their production. However, the process of chemical finishing (desizing, bleaching, dyeing, mercerising, etc.) requires larger fabric widths, meaning that the napkins and table cloth have to be stiched back together after weaving in order to obtain the appropriate width corresponding to the working width of the finishing machines. Uneven thread tension in the seam, as well as inner fabric tension, and exposure to chemical agents, in wet and dry conditions, with various temperature conditions, can affect the thread in a seam and cause the seam damage. According to the obtained results, it is apparent that the thread from the seams has a lower tensile stiffness compared to the thread that is treated in the same way in finishing processes and to the thread from the cross- wound cone. The tensile stiffness of the sewing thread decreases mostly after the bleaching process. By visual inspection, it was found that the sewing thread damage was very localized and by marking these points prior tensile testing, it is found that the thread breakpoints where on exact places.

The materials that are classified in the Mobiltech area, as a field of technical textiles, are witnessing fast growth, development and its share in the world textile market. Following the global ecological strategies, there is an increasing emphasis on the production and application of advanced textile materials with an ecological component, which will concurrently meet the high demand of the market. Accordingly, this paper presents an analysis of the textile material used for automotive application. The subject of the research is a textile material consisting of two components - woven and non-woven fabric, constructed in the way that the face and back of the fabric are made of nonwoven fabric, while the interior is made of woven fabric. The complex technological process of producing this material results in the realization of a textile material with exceptional properties, essential for the automotive application, such as softness, pliant and low mass, while retaining the properties of strength, resistance and comfort. Furthermore, this textile material satisfies a particularly important visual segment of aesthetic attractiveness as well as ecological acceptability.

Tensile response of a given material is recorded by the standard test in which the stress caused by the mechanical loading is evenly distributed in the test specimen. Textile materials are flexible and unable to withstand any in-plane compression. Compressive cut off can be viewed as the first source of the nonlinearity in textile deformation. This paper brings the study in which these nonlinear phenomena are illustrated on the case of the out-of-centre tensile load in the modified standard tension test, where the force is applied to the specimen via the rigid crossbar. If the negative stress of bending part surpasses the average tensile stress, compressive cut off takes place and the static conditions must be satisfied in the new situation of a reduced specimen.

This paper explores the influence of structural and structural characteristics of woven fabric made from meta aramide yarns on their thermal properties and properties associated with comfort. The aim of the research is related to the objectives of the project that supports this study and publication of this paper, which is development of woven fabric with improved thermal protection properties, produced on conventional weaving machines and designed by various fabric structures on the front and the back of the woven fabric with the selection of high performance fibers.

Istražena je primjena ekološko-prihvatljivog modificiranog prirodnog škroba (kukuruznog) u procesu škrobljenja kao samostalno škrobno sredstvo i u mješavini sa sintetičkim škrobom (polivinilalkoholom, PVA) i derivatom celuloze (karboksilmetilcelulozom, CMC). Istovremeno, tijekom škrobljenja mijenjao se postotak ulazne vlažnosti pređe prije samog procesa škrobljenja (škrobljenje bez i s prednamakanjem pređe). Ulazna vlažnost pređe s prednamakanjem bila je 50 %, a bez prednamakanja 5 %. Škrobljenje pređe odvijalo se na laboratorijskom škrobljarskom uređaju, s mogućnošću prilagođavanja industrijskim u1jetima. Ispitivanja su proredena na 100 % pamučnoj pređi finoće 20 tex. Prema dobivenim rezultatima može se zaključiti da: ekološki prihvatljiv modificirani prirodni škrob ima određenih nedostataka u odnosu na PVA i CMC, ali njihovo korištenje u mješavini daje vrlo dobre rezultate ; škrobljenje pređe s prednamakanjem ima prednosti i to u manjem škrobnom nanosu, većem prekidnom istezanju i prekidnim silama, kao i u manjem broju stršećih vlakanaca (dlakavost pređe), a njegov nedostatak je u manjoj otpornosti na habanje, u odnosu na pređu škrobljenu bez prednamakanja. Moguće je dobiti zadovoljavajuću kvalitetu škrobljene pređe korištenjem prirodnih ekološki prihvatljivih sredstava u mješavini sa PVA i CMC. Škrobljenje s prednamakanjem je ekonomičnije, a istovremeno kvaliteta škrobljene pređe je većinom bolja u odnosu na pređu škrobljenu bez prednamakanja.

Poslijediplomski sveučilišni studij Tekstilna znanost i tehnologija na Sveučilištu u Zagrebu Tekstilno-tehnološkom fakultetu (TTF) http://www.ttf.unizg.hr/index.php?str=104 ima posebno mjesto u istraživačkom prostoru visokog obrazovanja kao jedini studij u području tehničkih znanosti, znanstvenom polju tekstilna tehnologija u Republici Hrvatskoj. Ovaj studij nastavak je diplomskog sveučilišnog studija u cilju obrazovanja znanstvenika koji će produbiti teorijska znanja, metodologiju istraživačkog rada, razviti kritičko razmišljanje i dodatne prenosive vještine iz tekstilne tehnologije. Temelji se na istraživanjima iz polja tekstilno- mehaničkog inženjerstva, znanosti o materijalima, tekstilne kemije, tekstilne i odjevne tehnologije, te dizajna tekstila i odjeće.

Istražene su različite vrste zaštitnih materijala od elektromagnetskog (EM) zračenja. Ispitivanja učinkovitosti zaštite je provedena na uzorcima prije obrade te nakon 10 ciklusa kemijskog i mokrog čišćenja. Prema dobivenim rezultatima učinkovitost zaštite od (EM) zračenja se smanjuje s povećanjem broja ciklusa kemijskog i mokrog čišćenja.

Izrada tkanina, kao jedan od najstarijih zanata u povijesti čovječanstva, čini osnovu kulturne i etnografske baštine svakog naroda. Ovisno o podneblju iz kojeg potječu, tkanine su se izrađivale i ukrašavale različitim vrstama sirovina, vezovima, različitim gustoćama i finoćama niti, bojama, tehnikama tkanja. Svako povijesno razdoblje i podneblje dodaje nešto specifično i jedinstveno, što svaku tkaninu čini posebnom i prepoznatljivom. Usprkos nepostojanju visoko-sofisticiranih uređaja za izradu složenih struktura, povijesne tkanine su se odlikovale iznimnom konstrukcijskom složenošću. Neke od tkanina izrađenih složenim načinima tkanja su: Baršun i Velur tkanine mekane reljefne površine ; Brokati i Lamé tkanine iznimne ljepote i strukture sa zlatnim i/ili srebrenim potkinim nitima ; Gros de tours svilene tkanine iznimno velikih gustoća ; Lampasi tkanine izrađene provezivanjem više tkanina ; Taft svilene tkanine iznimne gustoće ukrašene lanciranim i broširanim potkama te mnoge druge.