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1

Tkaniny gofrowane – właściwości i zastosowanie

Matusiak Małgorzata

Przegląd Włókienniczy - Włókno, Odzież, Skóra

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2025

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nr 2

35--39

PL

Tkaniny gofrowane są specyficzną grupą tkanin o unikatowych właściwościach i wzornictwie. Są one uznawane za materiały trójwymiarowe (3D lub 2D+). Tkaniny gofrowane są znane i stosowane od lat, choć istnieją ograniczenia w ich rozpowszechnieniu. Właściwości tkanin gofrowanych były przedmiotem wielu badań, jednak nie zostały one w pełni opisane zwłaszcza w literaturze polskojęzycznej. Celem niniejszej publikacji jest przybliżenie czytelnikom informacji na temat metod wytwarzania, zastosowania oraz wybranych właściwości tkanin gofrowanych w oparciu o przykładowe tkaniny gofrowane bawełniane. W artkule opisano właściwości strukturalne, mechaniczne i biofizyczne wybranych tkanin gofrowanych wytworzonych z osnowy bawełnianej przy zastosowaniu dwóch rodzajów przędz wątkowych: bawełnianej i bawełniano-poliestrowej.

EN

Seersucker woven fabrics are a specific group of fabrics with unique properties and design. They are considered as three-dimensional materials (3D or 2D+). Seersucker woven fabrics have been known and used for years, although there are limitations to their widespread use. The properties of seersucker woven fabrics have been the subject of many studies, but they have not been fully described, especially in Polish-language literature. The aim of this publication is to provide readers with information on the methods of production, application and selected properties of seersucker woven fabrics based on exemplary seersucker cotton fabrics. The article describes the structural, mechanical and biophysical properties of selected seersucker woven fabrics manufactured from a cotton warp using two types of weft yarns: cotton and cotton-polyester.

2

Parametry techniczno‑użytkowe stolarki okienno‑drzwiowej w budynkach mieszkalnych

Kopyłow Ołeksij

Materiały Budowlane

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2025

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nr 8

236--237

3

Fabricating Metal Powder Filters with Material Extrusion Additive Manufacturing

Kim Min-Ji, Lee Min-Jeong, Kim Hyun-Ju, Kim Ju-Yong, Lee Jung-Woo, Yun Jung-Yeul

Archives of Metallurgy and Materials

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2025

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Vol. 70, iss. 3

1159--1163

EN

Metal powder filters are key components in semiconductor manufacturing equipment that play a critical role in preventing the ingress of impurities and fine particles that may be contained in process gases. With the increasingly advanced development of the semiconductor industry, metal powder filters also require more precise and advanced performance. Therefore, in this study, a filter with a honeycomb structure morphology with crossed top and bottom was fabricated by a material extrusion additive manufacturing (MEAM) process. To achieve this, the prepared pellets were subjected to the MEAM, allowing the creation of filters with complex shapes featuring crossed top and bottom structures. After polishing the surface of the specimen, solvent debinding and thermal debinding were performed to remove the binder. Solvent debinding was performed in n-Heptane for 24 hours, while thermal debinding was performed in an Ar atmosphere at a maximum temperature of 800°C. The debinded specimens were sintered under a high vacuum atmosphere at temperatures of 850°C, 950°C, and 1050°C, respectively. The prepared metal powder filters were examined for filter morphology and microstructure using optical microscopy, and pore properties such as porosity and air permeability were evaluated.

4

Wpływ cykli otwierania i zamykania na właściwości aluminiowych profilowych przeszklonych drzwi przeciwpożarowych

Sędłak Bartłomiej, Jakimowicz Marzena

Materiały Budowlane

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2024

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nr 2

30--38

PL

Drzwi przeciwpożarowe pełnią kluczową rolę w spełnieniu wymagań dotyczących bezpieczeństwa pożarowego obiektów budowlanych. Stanowić mają efektywną barierę dla ognia i dymu oraz wysokiej temperatury, dlatego też powinny mieć odpowiednią klasę odporności ogniowej oraz dymoszczelności, a także cechować się zdolnością do samoczynnego zamykania. Zgodnie ze stosowanymi powszechnie w Europie procedurami, każda z wymienionych cech określana jest niezależnie. W warunkach rzeczywistego pożaru może jednak dojść do sytuacji, w której drzwi przeciwpożarowe muszą zadziałać w prawidłowy sposób po wielokrotnych cyklach zamykania i otwierania. W artykule przedstawiono wyniki badań odporności ogniowej przeszklonych drzwi aluminiowych profilowych poddanych wcześniej badaniom cykli zamykania i otwierania. Cykliczne otwieranie i zamykanie drzwi powoduje zwiększenie przepuszczalności powietrza przez element. Może także wpływać na deformację skrzydła drzwiowego w trakcie badania odporności ogniowej, a w efekcie powodować utratę szczelności ogniowej.

EN

A fire door plays a key role in fulfilling the fire safety requirements of building structures. It is supposed to serve as an effective barrier to fire and smoke, which is why it should have an adequate fire resistance rating, smoke tightness class and it should feature a self-closing function. According to procedures applicable in Europe, each of the features mentioned above is determined independently. In real fire conditions, it might happen that the fire door shall work properly after many closing and opening cycles. This paper presents the results of fire resistance tests on aluminium framed glazed door previously subjected to closing and opening cycles. The numerous closing and opening cycles increase the amount of air migrating through the door. It may also affect the deformation of the door leaf during the fire resistance test. The consequence of which may be loss of fire integrity. However, it cannot be declared unequivocally that subjecting the door to a specific number of closing cycles causes a loss in its fire performance.

5

Exploration and Improvement of Room Temperature Properties for Organosilicon Slag Riser

Lu Jljun, Zhong Zhuofan, Hu Youngluan, Wu Di, Wang Huafang

Archives of Foundry Engineering

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2024

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Vol. 24, iss. 2

35--43

EN

Organosilicon slag, generated as a waste product from organosilicon monomer production, had limited options for resource utilization. Previous experiments utilized recovered organosilicon slag to partially replace heating materials in preparing exothermic insulating risers. However, the incorporation of organosilicon slag led to specific issues in the risers including low compressive strength, high resin addition requirement and easy ignition during drying. In order to address these problems, this study analyzed the effects of resol resin parameters and organosilicon slag on the ambient temperature properties of heating insulating risers through single-factor experiments. In addition, adjustment was made to the drying process and an optimal preparation scheme was determined via orthogonal experiments. The purpose of the study was to prepare risers with reduced resin content, increased organosilicon slag addition and adequate compressive strength. Results showed that selecting a resin viscosity of about 170 mPa.s and resin addition of about 13% allowed for relatively good compressive strength and air permeability with less resin required. Additionally, an organosilicon slag addition of 18-21% and particle size under 30 mesh(550 μm) was beneficial for improving compressive strength. Adjusting the drying process to a two-step heat preservation approach (180°C for 25 min, then 130°C for 35 min) slightly decreased compressive strength compared to the original process; nevertheless, it improved air permeability and prevented the risers from igniting spontaneously during subsequent drying. The optimized preparation scheme determined through orthogonal experiments involved 150 mPa.s resin viscosity, 14% resin addition, 21% organosilicon slag addition and slag particle size less than 30 mesh (550 μm). This yielded a compressive strength of 4.21MPa and air permeability of 75.6, exceeding the standard of the exothermic insulating riser: GB/T13040-2017.

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Prediction of air permeability and effective thermal conductivity of multifilament polyester yarn by finite element analysis

Siddiqui Muhammad Owais Raza, Farooq Salma, Husain Muhammad Dawood, Faisal Saira

Polimery

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2023

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Vol. 68, nr 1

6--18

EN

The effective thermal conductivity and air permeability of a multifilament polyester yarn used in sports T-shirts was investigated by computer modeling using finite element analysis (COMSOL Multiphysics, ABAQUS/CAE). It has been shown that the number of fibers, the porosity of the yarn and the proportion of fibers in the volume fraction of the yarn have a direct effect on the effective thermal conductivity and air permeability of the multifilament yarn. It was found that with the increase in the number of fibers, the porosity of the yarn decreases linearly, while the volume fraction of the fibers increases, and thus the effective thermal conductivity increases. In addition, air permeability decreases exponentially.

PL

Zbadano efektywne przewodzenie ciepła i przepuszczalność powietrza wielowłókienkowej przędzy poliestrowej stosowanej w koszulce sportowej poprzez modelowanie obliczeniowe z użyciem analizy elementów skończonych (COMSOL Multiphysics, ABAQUS/CAE). Wykazano, że liczba włókien, porowatość przędzy oraz udział objętościowy włókien w przędzy mają bezpośredni wpływ na przewodzenie ciepła i przepuszczalność powietrza przędzy wielowłókienkowej. Wraz ze wzrostem liczby włókien porowatość przędzy maleje liniowo, natomiast zwiększa się udział objętościowy włókien, a tym samym efektywne przewodnictwo cieplne. Ponadto przepuszczalność powietrza maleje wykładniczo.

7

Statistical Study on the Effect of Yarn Fineness on Heat and Mass Transfer Properties of Single Jersey Knitted Fabrics

Gunesoglu Sinem, Babalik Esin

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 5

1--9

EN

Heat and mass transfer properties of textile fabrics determine thermal comfort. This paper introduces a statistical study on the contribution of yarn fineness to the heat and mass transfer properties of single jersey cotton and polyester fabrics through relevant measurements. It is observed that yarn fineness affects those properties at different levels in differing fiber types.

8

”Papier z gumy”

Kmiotek Magdalena, Olejnik Tomasz P., Pietras Marta, Śliżewska Katarzyna

Przegląd Papierniczy

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2022

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R. 78, nr 9

525--529

PL

W pracy zbadano możliwość zabezpieczania papieru za pomocą celulozy bakteryjnej, która z chemicznego punktu widzenia jest czysta chemicznie i obojętna fizjologicznie. Dzięki zastosowaniu powłoki z celulozy bakteryjnej uzyskano całkowitą barierowość względem powietrza. Nowatorskim rozwiązaniem była hodowla celulozy bakteryjnej na pożywce ze zmielonej gumy.

EN

The possibility of paper protection with the use of bacterial cellulose was studied. From the chemical point of view bacterial cellulose is pure and physiologically neutral. Coating from bacterial cellulose has proven the ideal barrier against air. The novelty was the use of ground rubber as a base for bacterial cellulose culture.

9

Investigating the Functional and Comfort properties of a Face Mask Based on a Coolmax® Blended Cotton Fabric

Mamun Kabir Shekh Md., Hasan Md. Mahabub, Alam AKM Mashud

Fibres & Textiles in Eastern Europe

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2022

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Vol. 30, no. 3

102--110

EN

As the spread of Covid-19 has created a fatal threat to human survival, a comfortable and virus-deactivated functional face mask is extremely necessary. Herein, an appropriate thermally comfortable and highly breathable as well as virus-protecting functional knit fabric face mask was developed that consisted of multichannel PE Coolmax® yarn with cotton yarn. Due to the multichannel structure (four and six channels) of PE Coolmax® yarn with cotton yarn blended fabric, the fiber showed good filtration efficiency, air permeability, water vapour permeability and moisture management properties. In addition, the thermal conductivity and absorptive properties of the blended fabric based on the properties of PE Coolmax® yarn with cotton yarn make the face mask more comfortable for the user.

10

Durable Wash-Resistant Antimicrobial Treatment of Knitted Fabrics

Krisciunaite Jolita, Kalendraite Brigita, Ragelienė Lina, Merkelyte Evelina, Mikucioniene Daiva

Autex Research Journal

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2022

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Vol. 22, no. 4

373--382

EN

Antimicrobial finishing is increasingly used in textile products to increase their functionality. Antimicrobial properties became extremely important during the COVID-19 situation. The main problems faced by antimicrobial finishing are nontoxicity and durability (wash-resistance) of antibacterial activity. Also, it is important to determine whether the antimicrobial finishing changes comfort properties, such as air permeability. This paper deals with the durability of antimicrobial treatment, that is, resistance to washing, and effect on the structural changes that may have influence on the comfort properties, such as permeability to air. Knits of various raw compositions were antimicrobial-treated with the new commercial antimicrobial product, Si Bactericidal (Smart Inovation, Portugal). After the antimicrobial treatment, knitted specimens were washed 50 times and changes in their structural parameters, air permeability, and antimicrobial activity were measured. It was found that the mentioned antimicrobial treatment gives very good antimicrobial activity to the treated fabric and is wash-resistant and long-lasting. Also, it does not change dimensions and permeability to air of the treated fabrics with some exceptions of cotton-based knitted structures.

11

Air permeability and sorptivity of concrete modified with viscosity modifying agents

Kubissa Wojciech, Prałat Karol, Kania Szymon

Archives of Civil Engineering

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2022

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Vol. 68, nr 1

223--240

EN

The paper presents the effect of a viscosity modifying admixture (VMA) on the air permeability, sorptivity and strength parameters (compressive and tensile strength) of concrete. The Atlas VM-500 admixture used in the research is a well-known additive that is commonly applied in concrete technology. Air permeability tests were carried out using the Torrent method. It was found that viscosity modifying admixtures (VMAs) have a significant impact on the permeability of concrete. The lowest values of the kT coefficient were obtained for specimens that matured in a water environment, and which contained 0.5% of VMA. This amount of additive reduced permeability by 34% when compared to the reference series of concrete. For air-conditioned specimens with 1.2% of VMA, the maximum decrease was 28% when compared to the reference samples. In the case of samples conditioned in an environment with an increased humidity, the maximum decrease occurred with a lower VMA content of 0.5% and amounted to 27% when compared to the reference samples. In addition, it was shown that the addition of 1.2% of VMA improved the compressive strength of concrete by 2.3% during its curing in water. In turn, this amount of VMA deteriorated its strength by 10.4% when the specimens were conditioned in air, and by 8.1% when they were conditioned in high humidity.

PL

Mineralne materiały budowlane, w tym także betony cementowe posiadają porowatą strukturę, które bardzo łatwo mogą penetrować ciecze i gazy znajdujące się w środowisku naturalnym. Dlatego też wprowadza się miarę, powiazaną z trwałością betonu tzw. przepuszczalność, którą określić można na drodze pomiaru wielkości charakteryzujących przepływ cieczy lub gazów. Bardzo często na potrzeby oceny potencjalnej trwałości betonu prowadzony jest pomiar nasiąkliwości lub sorpcyjności [6-8, 33]. W celu oceny przepuszczalności coraz częściej uznanie znajduje metoda Torrenta [19-21]. Pomiar ten ogranicza się do przepływu powietrza w kilkucentymetrowej, powierzchniowej warstwie betonu. Na przepuszczalność betonu mierzoną różnymi metodami, bardzo istotny wpływ ma jego stan wilgotnosciowy [29-32]. W przypadku metody Torrenta problem ten został przez jej twórców rozwiązany na drodze doświadczalnego ustalenia tego wpływu i wyposażeniu aparatu w sondę do pośredniego pomiaru wilgotności betonu, której zastępczą miarą jest jego oporność właściwa. Celem niniejszej pracy było określenie wpływu zastosowanych w betonach dodatków VMA na przepuszczalność powietrza oraz sorpcyjność, jak i parametry wytrzymałościowe (ściskanie i rozłupywanie) otrzymanych kompozytów, pielegnowanych przez 28 dni w zróżnicowany sposób.

12

Diagnostics of air permeability of concrete in abutments of the viaduct in Płock

Kubissa Wojciech, Dobaczewska Wioletta

Roads and Bridges - Drogi i Mosty

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2021

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Vol. 20, no. 2

157--171

EN

The durability of reinforced concrete engineering structures is related to the resistance of the reinforcement cover to the penetration of aggressive liquid and gaseous media. According to Eurocode recommendations, the cover thickness should be adapted to the aggressiveness of the environment. Attempts are being made to use measurements of air perme- ability of concrete to assess the concrete integrity in the cover layer in order to detect possible imperfections in workmanship. The paper presents the results of air permeability test using the Torrent method carried out on the abutments of the road viaduct built in Płock. The abutments were made of air-entrained concrete of strength class C35/45, designed for exposure classes XC4, XD3, XF2. The air permeability test was carried out in accordance with Swiss standard SIA 262/1 to verify the quality of concrete in the structure. Air permeability measurements were also made on moulded control specimens for comparison. The usefulness of the method allowing for non-destructive verification of the cover layer uniformity in reinforced concrete structures was demonstrated.

PL

Trwałość żelbetowych konstrukcji inżynierskich jest związana z odpornością otuliny zbrojenia na wnikanie agresywnych mediów ciekłych i gazów. Zgodnie z zaleceniami Eurokodu, grubość warstwy otuliny powinna być dostosowana do agresywności środowiska. Podejmuje się próby wykorzystania pomiarów przepuszczalności powietrza przez beton do oceny szczelności betonu w warstwie otuliny, aby wykryć ewentualne niedoskonałości wykonawcze. W artykule zaprezentowano wyniki badania przepuszczalności powietrza metodą Torrenta wykonane na przyczółkach drogowego obiektu inżynierskiego zbudowanego w Płocku. Przyczółki wykonano z betonu napowietrzonego klasy wytrzymałości C35/45, zaprojektowanego do klasy ekspozycji XC4, XD3, XF2. Kontrolę przepuszczalności powietrza przez beton przeprowadzono zgodnie ze szwajcarską normą SIA 262/1 w celu weryfikacji jakości wbudowanego betonu. Pomiary przepuszczalności powietrza wykonano również na formowanych próbkach kontrolnych w celach porównawczych. Wykazano przydatność metody, pozwalającej w sposób nieniszczący zweryfikować jednorodność otuliny w konstrukcji żelbetowej.

13

Investigation of the Influence of Stretch on the Air Permeability of Knitted Fabric: Effect of Loop Length

Kumar V., Prakash C., Manigandan G., Sampath V. R.

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 1 (145)

53--56

EN

Most of the time, a certain degree of stretch prominently and incrementally occurs in intimate wear, leisure wear, sportswear, medical textiles etc., during their action. Variations in the stretch gradient would definitely cause changes in the air permeability of knitted fabrics. The influence of variables such as loop length, the presence of an elastomeric component and fabric structure on the air permeability of cotton single jersey and pique knitted fabrics in a stretched state was critically analysed. In this work, changes in the air permeability of cotton jersey samples with and without elastomer were investigated and reported by keeping the samples in static up to an incremental stretch of 40% at a rate of 10% of the stretch gradient, in a dry relaxed state, wet relaxed state and fully relaxed state.

PL

W większości przypadków, podczas użytkowania odzieży rekreacyjnej, sportowej, medycznej itp. występuje pewien stopień rozciągnięcia. Wahania gradientu rozciągliwości powodują zmiany przepuszczalności powietrza dzianin. W pracy przeanalizowano wpływ zmiennych, takich jak: długość pętli, obecność składnika elastomerowego i rodzaju struktury na przepuszczalność powietrza dzianin bawełnianych typu single jersey i typu pique w stanie rozciągniętym. W pracy zbadano i odnotowano zmiany przepuszczalności powietrza w przypadku próbek dżerseju bawełnianego z elastomerem i bez elastomeru, utrzymując próbki w stanie statycznym do przyrostowego rozciągnięcia 40% z 10% gradientem rozciągania w stanie mokrym i suchym.

14

Comparative Study on the Water Vapour Permeability of Textile by a Standard and Novel device

Mazari Adnan, Havelka Antonin, Naeem Jawad, Adamek Karel

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 6 (150)

59--64

EN

Thermo-physiological properties are very much connected to water vapour and air permeability. There are multiple standards with different working principles to determine the exact performance of any textile material. However, most of these tests are time-consuming and work on the steady state principle, whereas few devices work on heat flux, where results can be obtained much more quickly. The research article covers the testing of 8 unique shirt samples on these devices compared that on a novel device created by the author to see how much the results differ from each other. Lastly, a theoretical approach was used to determine any correlation between air permeability and water vapour permeability. The research work helps in understanding the working of different devices used for water vapour permeability and allows a reduction in time by using a predictive approach with just the results from the air permeability machine.

15

Comparative Study on the Properties of Taped Seams with Different Constructions

Kara Sukran, Yeşilpınar Sevil

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 2 (146)

54--60

EN

Ready to wear end-products may be obtained by different assembling methods such as sewing, bonding, seam taping, welding and pressing fabrics. Currently, sewing is the most common method, but other techniques are improving day by day in accordance with the new application areas and new requirements from seamlines. Seam taping is an innovative alternative method that can improve the properties of seams. In this study, some essential properties such as the strength, elongation, thickness and air permeability of sealed samples with different constructions were compared. As taping constructions, ultrasonic bonding plus taping, sewing plus taping, and only taping methods were used. These methods were varied according to the taping temperature and speed. Also, only sewn and ultrasonically bonded samples were prepared as reference samples. In total, 20 different kinds of seam sealed samples were obtained as test materials. According to the results, taped samples were advantageous in terms of seam thickness and seam strength properties when compared to only sewn and ultrasonically bonded references. Especially, "only taped" samples were one step ahead among the all constructions. The air permeability of the taped seams decreased by a certain amount, but it is thought to be tolerable in a full garment.

PL

Gotowe do noszenia produkty końcowe można otrzymać różnymi metodami łączenia, takimi jak: szycie, podklejanie, zgrzewanie i prasowanie tkanin. Obecnie szycie jest najpowszechniejszą metodą, ale inne techniki są z dnia na dzień udoskonalane zgodnie z nowymi obszarami zastosowań i nowymi wymaganiami dotyczącymi szwów. Podklejanie szwów to innowacyjna, alternatywna metoda, która może poprawić właściwości szwów. W badaniu porównano niektóre istotne właściwości, takie jak: wytrzymałość, wydłużenie, grubość i przepuszczalność powietrza próbek o różnych konstrukcjach. Jako konstrukcje z taśmami zastosowano klejenie ultradźwiękowe plus taping, szycie plus taping i tylko taping. Metody te były zróżnicowane w zależności od temperatury i prędkości taśmowania. Jako próbki referencyjne przygotowano również próbki szyte i wiązane ultradźwiękowo. W sumie uzyskano 20 różnych rodzajów próbek zgrzewanych jako materiały testowe. Zgodnie z wynikami próbki oklejone taśmą były korzystne pod względem grubości szwu i właściwości wytrzymałości szwu w porównaniu z wzorami zszywanymi i łączonymi ultradźwiękowo. W szczególności próbki „tylko zaklejone” były o krok przed wszystkimi konstrukcjami. Przepuszczalność powietrza w szwach klejonych zmniejszyła się o pewną wartość, ale uważa się, że może być to tolerowane.

16

Moisture and Thermal Transport Properties of Different Polyester Warp-Knitted Spacer Fabric for Protective Application

Chen Qing, Shou Dahua, Zheng Rong, Tang Ka-Po Maggie, Fu Bailu, Zhang Xiaoting, Ma Pibo

Autex Research Journal

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2021

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Vol. 21, no. 2

182--191

EN

Warp-knitted spacer fabrics are generally used for sportswear, functional clothing, protective clothing, and other applications. This article studied the heat and mass transfer properties of polyester warp-knitted spacer fabrics from low thickness (2 mm) to high thickness (20 mm), from low mass (247.34 g/m2) to high mass (1,585.9 g/m2), and surface structure in plain or mesh construction. Water vapor permeability, air permeability, water absorption, and thermal insulation property were conducted to evaluate the spacer fabrics. The results revealed that with increasing volume density the water vapor permeability of spacer fabrics decreased, but the water absorption ratio increased. The water vapor permeability of fabrics increased when thickness decreased and volume density increased. It was further found that spacer fabrics with mesh worn nearby the skin and plain structure worn far from the skin could facilitate water vapor and air transmission. The difference of 8.82% for water vapor permeability and 14.19% for air permeability were found between testing mesh side up and down for the spacers (2.56 and 3.37 mm), respectively. Thermal insulation ratio was highly and significantly correlated with heat transfer coefficient at −0.958 and with thickness at 0.917. Thermal insulation ratio is highly and significantly correlated with air permeability at 0.941.

17

The Impact and Importance of Fabric Image Preprocessing for the New Method of Individual Inter-Thread Pores Detection

Owczarek Magdalena

Autex Research Journal

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2020

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Vol. 20, no. 3

250--262

EN

The paper describes the impact and importance of preprocessing methods of fabric image for detection of inter-thread pores (ITP), which is a new method of individual ITP identification. The aim of this experiment is to identify precisely every individual ITP of fabric structure by using optimal preprocessing algorithm for further quantitative, morphometric structural analysis of specialized fabrics (barriers, industrial filters, composites, others) in context of air permeability, flow resistance, UV radiation, viruses penetration, thermal comfort by estimation fabric porosity, especially macroporosity parameters and cover factor. The correct identification of individual ITP depends on the acquisition method and the preprocessing algorithm. It was conducted by analyzing the adaptation of digital image preprocessing methods for two structures of plain weave fabric in two magnification zooms, 1.25 and 0.8. Preprocessing operations were performed in the area of spatial operations of the image. The optimal preprocessing algorithm includes low-pass filtering, histogram equalization, nonlinear filtering, thresholding, and morphological operation. This algorithm was selected based on the factors developed by the author (ITP detection, RID factor—a difference between the real and model ITP areas) which rely on the ITP size, shape, and location. The graphic view of the ITP contour position on the fabric image is a verification element in the optimal preprocessing algorithm. The presented results of the air permeability of two different plain weave structures confirm the need to optimize the algorithm of pre-image processing methods to precisely detect each individual ITP in the fabric image.

18

Introducing a Newly Developed Fabric for Air Filtration

Hakam Mohamed, Hashima Wael, Elhawary Ibrahim, Elgeiheini Adel

Autex Research Journal

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2020

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Vol. 20, no. 2

148--154

EN

Woven and nonwoven fabrics present filtration efficiency higher than other air filtration media. Fabrics are selected according to air flow conditions and particle characteristics. The majority of air filtration media are nonwoven fabrics because of their cost, but they need high filtration area for high efficiency. Modified construction of woven fabric introduces high performance in air filtration and decreases filter size, which tends to have better competition abilities. The designed fabrics have considerable thickness and suitable pore characteristics by applying roving instead of weft yarns. Four factors (roving count and their turns per inch, picks per inch and fabric designs) were varied in order to study the effect of these factors on their performance in filtration. Optimum operating conditions for a determined range of air permeability and pore size were obtained.

19

Analysis of Factors Affecting Thermal Comfort Properties of Woven Compression Bandages

Aboalasaad Abdelhamid R.R., Skenderi Z., Kolčavová S. Brigita, Khalil Amany A.S.

Autex Research Journal

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2020

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Vol. 20, no. 2

178--185

EN

Compression bandage (CB) as a porous material should provide both graduated pressure and thermal comfort properties to enable air permeability, heat transfer, and liquid perspiration out of the human body. The main factors affecting thermal comfort properties are the temperature difference between environment and skin, yarns’ structure and material, fabric thickness, porosity, areal density, number of fabric layers, trapped air, and fabric structure. Thermal resistance (Rct) and water vapor resistance (Ret) are evaluated for four types of woven CBs. All bandage types were applied at the range of extension (10–80%) using both two- and three-layer bandaging on thermal foot model (TFM). Rct values are compared with measured results by the Alambeta instrument, whereas Ret test is performed on the Permetest device. Thermal resistance is significantly decreased when increasing the bandage extension from 10 to 40%, then it is slightly increased by increasing the extension from 40 to 60%, after that it is decreased especially at 80% extension due to lower bandage thickness and higher compression.

20

Nowa metoda wytwarzania papierów workowych o podwyższonej przepuszczalności powietrza

Olejnik Konrad, Filipczak Kamil

Przegląd Papierniczy

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2019

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R. 75, nr 9

586--590

PL

Wykonano badania nad możliwościami zwiększenia przepuszczalności powietrza papierów przeznaczonych do wytwarzania worków. Porównano skuteczność stosowanej obecnie metody poprawy tego parametru poprzez perforowanie struktury materiału na sucho z nową metodą polegającą na wykonaniu tej operacji wówczas, gdy wstęga papieru jest jeszcze w stanie mokrym. Na podstawie otrzymanych wyników stwierdzono, iż zaproponowana metoda umożliwiła utrzymanie akceptowalnego kompromisu pomiędzy przyrostem przepuszczalności powietrza wytworów papierniczych oraz niewielką utratą ich parametrów wytrzymałościowych (w odniesieniu do efektów uzyskiwanych drogą perforacji na sucho).

EN

Research works related to the problem of the improvement of air permeability for sack papers were conducted. Comparison of the effectiveness of currently used method based on the puncturing of dry paper with newly proposed method was done. New method is based on the puncturing of paper which is still in wet state. Obtained results show that proposed method allows to maintain the acceptable compromise between obtained high air permeability and acceptable decrease in strength properties of the processed paper.