Comfort Comfort freedom from pain discomfort a neutral state o A pleasant state of physiological psychological and physical harmony between human and environment o Can be relative or subjective o Physiological or psychological thermal sensorial mobile Human comfort o Psychological comfort implies individuals need specific garments fabrics and colors and design features to help them feel confident and at ease within various roles o Factors self mage relationship with others need or privacy o Physiological comfort maintenance of thermal balance proper relationship between body heat production and loss o Factors cardio system skeleton muscular system central nervous system pulmonary system digestive system thermoreg mechanism o Physical aspects of comfort different sensations and feelings of discomfort pain influence two types of comfort o Factors touch sight hearing taste smell Comfort related physical properties of textiles o Thermo physiological comfort thermal resistance water vapor permeability wickability sorption of water water resistance repellency and proofness drying rate o Sensorial neurophysiological comfort prickliness itchiness inflammation roughness thermal character warm or cool feeling electrostatic propensity o Body movement comfort stretch weight pressure compression o Hand tactile sensation may be by touch or sight using touching subjective assessment Affected by Body temperature skin temp 90 92 degrees Room temperature Psychological state of being Physiological state of being Association Subject hand you will be touching the fabric with your eyes closed o Rate the fabric on a scale from 1 7 on the following Pliabile to stiff Stretchy to non stretchy Springy to limp Smooth to rough Compact to open Cool to warm Harsh to slippery Soft to hard Fabric drape the manner which a fabric hangs over 3D form o How a fabric bends under its own weight is an indication of drapability Highly drapeable fabric that falls in numerous vertical folds o No standard requirement more of a judgment call Drape coefficient range is 0 100 measure the shadow o Above 50 stiff and not very drapeable o Example most denim is not considered drapeable Drape affected by o Fiber content some fibers stiffer than others depends on size inherent characteristics Rayon known for drapeability o Yarn structure tightly constructed yarns will have less drapeability loosely constructed yarns will have more o Fabric structure high fabric count makes compact structure which will have less drape Moisture absorbency o Ability of a material to take in or absorb another material o Ability to retain liquid in interstices pores and internal portions o Evaluate how quickly liquid absorbed and quantity absorbed at saturation point AATCC 79 absorbency of bleached textiles bleached dyed or printed materials o Drop water onto material held under tension Specular reflectance shiny reflective surface of water drop when it beads up on surface Water repellency relative resis of material to surface wetting water penetration or water absorption Water resistance ability of material to withstand penetration by water under pressure or water that drops from a distance and strikes against material with known force Waterproof resistant to water penetration regardless of pressure or force Water vapor transmission speed with which water vapor passes through the material Dessicant method known weight of dried calcium chloride placed in container covered by material see weight gain Water method specimen covers pan containing known amount of water water loss by evaporation measured both procedures measure water transmitted in 24 hour period Physical Characteristics of textile materials influencing thermal comfort o Fabric mass thickness fiber yarn fabric structures Porosity ratio of air to space to the total volume of the fabric as a percent Cover factor the opacity or hiding power in textiles Physics of human comfort body metabolism heat transfer evaporation Heat Transfer transfer of heat energy from one environment to another o Occur whenever temperate difference exists between two environments heat moves from the warmer surface or area to the cooler surface or area Models of heat transfer o Conduction transfer of heat by physical contact either within body or between two touching bodies o Convection is heat transfer a moving air mass within space o Radiation involves heat transfer through space in the form of electromagnetic energy Effects of fabric properties on heat transfer factors affecting moisture transfer finishes applied o Fiber type structure yarn type structure fabric type structure Anti static finishes conditions for static electric charge buildup are cool dry environment manufacturer fibers build up static charge between They are hydrophobic and don t allow conduction of electric charges o Work by making the material better conductor of electrical charges often means the material must become more absorbent Healthy adult human body o Can tolerate 5000 volts of electric charges o Sometimes too much for safety sensitive areas where there might be life saving equipment or other electronics in areas where there would be life threating situations max allowed is 2500 volts Moisture transfer transfer of liquid water or vapor o Transfer of moisture generally from wetter environment to the dryer until equality is reached o Moisture produced by body in form of perspiration o Type of moisture transfer diffusion absorption wicking evaporation Hydrophilic vs hydrophobic o Air permeability degree to which material is penetrable by air rate of air flow through a fabric when there s a different air pressure on either surface of the fabric Flammability Combustion chemical process with oxidation produces heat energy o Flaming combustion most familiar o Spontaneous combustion o Flameless combustion smoldering By products of combustion o Smoke primary cause of deaths o Toxic gas include carbon monoxide is most toxic others include CO2 and HS o Molten polymer compounds melting and dripping Limiting oxygen index o Determining that certain fibers need a certain amount of oxygen in the air to burn or not burn the amount of oxygen required to support the combustion of the fiber Normal environment 20 oxygen o Fibers with LOI above 21 self extinguish Cellulosics 17 20 Wool 25 2 Manufacture 18 2 20 6 Flame resistance property of a material whereby flaming combustion is prevented terminated or inhibited following application of a source of ignition o