Leather can be defined as a protein based fibrillary network, which consists mainly from collagen. The look, length and thickness of these fiber bundles are different in various organs of the body. Thus, leather is not a uniform material from a structural perspective and the properties of a leather piece depend on the position and direction over its area. The aim of this study was to measure some physical properties of goatskin leathers such as tear load, tensile strength and extension over the whole area and to draw maps showing regional variations. For this aim, whole the surface areas of 12 goatskin leathers have been sampled. Thickness, tear load, tensile strength and extension at break values of each sample have been measured and recorded. Then maps were drawn by using MATLAB (Matrix Laboratory) software that allows matrix manipulations, plotting of functions and data. The findings showed that the tear load, tensile strength and extension properties change directionally and locational over the area of the leather. These maps will provide information for usage area of the leathers especially for cutting in footwear production.

In this study, possibility of using Skipjack Tuna (Katsuwonus pelamis) fish skins as a new and alternative raw material source for leather industry was investigated. The structural and chemical properties of fish skins have a high impact on the preparation of special production recipes and the manufacturing of high performance valuable fish leathers. For this purpose, characteristic properties of Skipjack Tuna fish skins were evaluated by histological, histochemical and chemical methods. The chemical characteristics of fish skins were determined by analyzing fat content (%), total Kjeldahl nitrogen (%), hide substance (%), volatile matter (%), total ash (%) and fatty acid methyl esters and total amino acid content through instrumental analysis. Histological and histochemical analyses were carried out by Hematoxylin-Eosin and Van Gieson staining techniques. As a result of histological and histochemical investigations, fish skins were found thin and tough due to their surface characteristics, had less collagen content compared to other raw materials commonly used in leather industry and the fibers were orientated in parallel but opposite to striated muscles differently from the other skins. Besides, the fat content, Kjeldahl nitrogen, hide substance, volatile matter and total ash of Katsuwonus pelamis fish skins were found 24.47±1.76%, 10.20±0.28%, 57.32±1.55%, 37.33±4.01% and 1.23±0.0002% respectively. The results of the study revealed that Katsuwonus pelamis fish skins could be an alternative raw material to be used in the production of high value added luxury leathers.

Tulum cheese is a traditional cheese type of Turkey, which the ripening process of the cheese is carried out in sheep and goat skins. Although there are some industrial casings, sheep and goat skins are still the commonly preferred casing materials in traditional Tulum cheese production due to the natural favor and taste that give to the cheese characteristics. The difference of these natural casing materials, such as type, age, gender and sex, gives different tulum cheese quality. But not only a high quality cheese production but also the utilization of the skins used in tulum cheese production is carrying a great importance in environmental point of view. In this study, the utilization possibilities of raw skins that become the waste of the food industry after the tulum cheese production were investigated in terms of physical and chemical properties. For this purpose, forty eight (48) raw skins in different type (goat and sheep skins), age (6 months, 1 and 2 years old) and gender (male and female) were examined. The physical tests such as tensile strength and percentage of extension, double edge tear strength, shrinkage temperature, water vapor and air permeability determination; the chemical analysis such as pH, matters soluble in dichloromethane and Kjeldahl nitrogen analysis were performed to reveal the usage possibilities of these raw materials for the leather or relevant industries.

Wear comfort and hygiene is responsible for the significant improvement in the life quality of many amputees and in this regard liners have an important role for the prosthetic leg users. They are protective materials used as covers and worn over the residual limb before the socket to prevent the discomfort occurred during the movements of the patients. Liners are made of different synthetic flexible materials and designed with specific features for different suspension systems. Selecting a correct liner depends on the activity level and needs of the users in addition to the suspension system of the prosthetic leg. Although liners ensure wearing comfort to the users, feeling uncomfortable occurs due to perspiration and lack of evaporation. In this context, leather has advantages due to its triple helix collagen fibers and seems to be a perfect alternative natural material to synthetic liners. For this purpose, the production of a leather liner as an alternative to synthetic liners was aimed to perform for the prosthetic leg users. Chromium free leathers were manufactured based on the properties of the synthetic liners found in the market and the physical, mechanical and comfort properties of the liners in terms of water vapor permeability, static water absorption, tensile strength, elongation at break, tear strength, rubbing fastness and thickness were determined. The results revealed that leather could be used as an alternative natural liner for the use of prosthetic legs and has become prominent due to its wear comfort, hygiene and mechanical properties. KEY WORDS: leather, prosthesis, liner PIELEA CA POTENŢIALĂ CĂPTUŞEALĂ PENTRU PROTEZE REZUMAT. Confortul în purtare şi igiena sunt responsabile pentru îmbunătăţirea semnificativă a calităţii vieţii multor persoane cărora li s-au amputat membre şi, în acest sens, căptuşelile au un rol important pentru utilizatorii de proteze. Acestea sunt materiale de protecţie folosite ca înveliş şi purtate peste membrul rezidual înainte de a pune proteza pentru a preveni disconfortul care apare în timpul mişcării pacienţilor. Căptuşeala este fabricată din diferite materiale sintetice flexibile şi proiectate cu caracteristici specifice pentru diferite sisteme de suspensie. Selectarea unei căptuşeli corecte depinde de nivelul de activitate şi de nevoile utilizatorilor, pe lângă sistemul de suspensie al piciorului protetic. Deşi căptuşeala asigură confortul purtătorilor, senzaţia de disconfort apare din cauza transpiraţiei şi a lipsei de evaporare a acesteia. În acest context, pielea are avantaje datorită fibrelor de colagen cu structură de triplu helix şi, fiind un material natural, este o alternativă perfectă pentru căptuşelile sintetice. În acest scop, s-a propus căptuşeala din piele ca alternativă la căptuşelile sintetice, funcţională pentru utilizatorii de proteze. Pieile fără crom s-au fabricat pe baza proprietăţilor căptuşelilor sintetice găsite pe piaţă şi s-au determinat proprietăţile fizice, mecanice şi de confort ale căptuşelilor în ceea ce priveşte permeabilitatea vapo...