Higher Denier Research Articles

Disperse dyes, temperature and yarn parametre's effect on microfibre shedding of polyester spun yarn

The yarn dyeing factories discharge liquid waste laden with a variety of hazardous substances, including microplastic fibre (MPFs), which are found in aquatic ecosystems. During dyeing, MPF shedding factors were determined in this study. Shedding factors were determined at six polyester yarn dyeing factories to assess MPF release for (1) dark and (2) light shading. Three dyeing processes were considered including normal, carrier and high temperature. Sawdust-based activated carbon was utilized to decolourize dye wastewater. Flocculation and clarification were done without a flotation process to obtain low-density MPF. A hot needle test was applied to visual identification under an optical microscope and quantification was done by filtering, weighting and count of the yarn. A maximum of 0.00399 % weight loss (wt.) was found for dark shade in the high-temperature dyeing process and 0.00392 % (light) was found in carrier dyeing to dye a coarser yarn. In contrast, 0.4562 mg L−1 fibre particles (≤ 0.225 mm) shedding in normal dyeing, for a light shade, was observed to a fine yarn where a minimum of 0.00138 % wt. was found. Shorter fibre length, higher denier, and courser yarn were associated with the greatest MPF discharge at high-temperature dyeing for a dark shade. The usual effluent treatment plant (ETP) of the textile industry can remove only 75.52 % MPFs of wastewater. Shedding of MPF during dyeing is remarkably higher than the domestic wash cycle of garments. Wastewater of textiles containing MPFs would appear as a regular and extensive initial source of MP emissions, which can damage the ecological system.

Development of Bulky Silk Knitting Fabric

The denier of raw silk is enlarged by selected high denier cocoon silk and combined silk filament. The silk impregnating agent was mixed with hot water in order to enhance the softness of silk when reeling silk. After reeling, the silk and polyester partially oriented yarn（POY）were combined and textured by mechanical force and heat, and the silk multifilament with physic mechanical and geometric distortion was produced. Several silk multifilaments were fed together into the yarn carrier of coarse V-bed flat machine and grey cloth was knitted. The silk knitting fabrics with coarse style were produced through refining and drying. Such fabric, which bulkiness, elasticity and drapability are excellent, is suitable for kinds of knitting outer wear.

Denial in patients with a first-time myocardial infarction: relations to pre-hospital delay and attendance to a cardiac rehabilitation programme

Survival of a myocardial infarction and subsequent prognosis are highly dependent on the time between onset of symptoms and medical intervention. This cross-sectional study examines whether patients who used the psychological defence mechanism of denial when faced with symptoms of a first-time myocardial infarction tended to also show a prolonged delay in going to the hospital and to be less willing to participate in a cardiac rehabilitation programme. One hundred and seven patients, 78 men and 29 women, were enrolled in this study. The sample was divided into two groups depending on whether the patients sought medical help within 4 h after they began experiencing myocardial infarction symptoms (non-delayers) or whether they waited longer (delayers). Denial was measured with the Hackett and Cassem semi-structured interview 3-5 days after the patients entered the hospital. Data on participation (attenders) or not (non-attenders) in the rehabilitation programme was also obtained. Forty-nine patients exhibited a prolonged delay and 76 patients did not attend the rehabilitation programme. Both prolonged delay and a lesser readiness to attend the rehabilitation programme that was offered were related to a greater use of denial. In addition, the great majority of the patients categorized as being high deniers were found to also be both delayers and non-attenders. The results suggest denial to increase the health risks of persons potentially prone to myocardial infarction. If our knowledge about this psychological defence mechanism is increased, we might be able to reach more patients in alternative and individually based cardiac rehabilitation programmes.

Denial in patients with a first-time myocardial infarction: relations to pre-hospital delay and attendance to a cardiac rehabilitation programme

Survival of a myocardial infarction and subsequent prognosis are highly dependent on the time between onset of symptoms and medical intervention. This cross-sectional study examines whether patients who used the psychological defence mechanism of denial when faced with symptoms of a first-time myocardial infarction tended to also show a prolonged delay in going to the hospital and to be less willing to participate in a cardiac rehabilitation programme. One hundred and seven patients, 78 men and 29 women, were enrolled in this study. The sample was divided into two groups depending on whether the patients sought medical help within 4h after they began experiencing myocardial infarction symptoms (non-delayers) or whether they waited longer (delayers). Denial was measured with the Hackett and Cassem semi-structured interview 3–5 days after the patients entered the hospital. Data on participation (attenders) or not (non-attenders) in the rehabilitation programme was also obtained. Forty-nine patients exhibited a prolonged delay and 76 patients did not attend the rehabilitation programme. Both prolonged delay and a lesser readiness to attend the rehabilitation programme that was offered were related to a greater use of denial. In addition, the great majority of the patients categorized as being high deniers were found to also be both delayers and non-attenders. The results suggest denial to increase the health risks of persons potentially prone to myocardial infarction. If our knowledge about this psychological defence mechanism is increased, we might be able to reach more patients in alternative and individually based cardiac rehabilitation programmes.

Dye distribution in the dyeing of mixed denier polyester fabrics

Microfibre polyester is sometimes blended with higher denier fibres to achieve good aesthetic effects at lower cost. Two polyester yarns of 1.4 and 0.7 denier were dyed singly and together with a range of depths of CI Disperse Blue 79, and the dye distribution over the course of the dyeings was examined. The uptake is initially greater on the microfibre, but as dyeing is continued the distribution becomes more even, and eventually the same concentration of dye is present on both fibres. Based on the common observation that a given concentration of dye produces a lighter shade on a microfibre, the redistribution of dye during the process causes a continuing shade change even though the bath exhaustion is constant. A mixture of three dyes produced a stable hue on a fabric of 1.0 denier polyester after 20 min at a fixed dyeing temperature, but when dyed on a fabric of 1.0 and 0.5 denier yarns, a change in hue continued for more than 60 min.

Carpet properties that affect the retention of cat allergen.

Although the importance of carpeting on airborne levels of cat allergen (Fel d 1) has been demonstrated, no studies have been performed to determine specific properties of carpet that may affect its retention and removal. This study characterizes factors that affect the retention of cat allergen on tufted carpets. The experiments were designed to test the hypothesis that the amount of allergen-containing dust recovered from vacuum samples of tufted carpet sources was dependent on micro (fiber) or macro (construction) retention properties of carpets. Twenty-six types of custom manufactured carpet were spiked and embedded with reference dust containing Fel d 1. A standardized vacuum surface sampler was used to recover dust from the samples. Allergen was assayed using a standard, monoclonal antibody ELISA. Carpet-surface area and fluorocarbon-fiber treatments were found to have the largest effects on retention and recovery of cat allergen. The style per se of a carpet, such as loop or cut pile, does not affect allergen retention. These results are generally in agreement with previous studies on dust mite allergen retention. Carpets that are easiest to clean would have the following properties for release of cat allergen and in this order: low pile density and height, fluorocarbon coating of fibers, high denier per filament, and a fiber shape with a low surface area.

Effect of stretch on the ultraviolet spectral transmission of one type of commonly used clothing.

The spectral ultraviolet (UV) transmission through stockings was measured in field and laboratory based trials using a spectroradiometer. From these spectral UV measurements, the ultraviolet protection factor (UPF) was calculated. The UPF of stockings measured in the field was generally higher than that measured in the laboratory when using a quartz tungsten halogen light as the UV source. The UPF of 50 denier stockings decreased 868% when stretched 30% from their original size. Doctors recommending and patients using high denier stockings for patient photoprotection should be aware of the dramatic decrease in UPF when the stocking is in a stretched position, such as over a human leg.

A New Zealand replication of the IPAM clustering model for low back patients.

This study examined the reliability of the three-cluster model for chronic low back pain patients found using the Integrated Psychosocial Assessment Model (IPAM). A replication study using a sample of patients from a different country was completed. Seventy patients (average age = 47.05 years, SD = 16.11) with chronic low back pain of noncancer origin participated in the study. Sixty-two of these patients were attending The Auckland New Zealand Regional Pain Service, while a further eight were attending a private practice pain service in Auckland. Subjects were assessed on the IPAM, which measures pain intensity, disability, coping strategies, attitudes towards and beliefs about pain, depression and illness behaviour, the Medical Examination and Diagnostic Information Coding System, and the Multidimensional Pain Inventory. Cluster analyses using the kappa-means algorithm were performed on the IPAM data. The three-cluster solution was preferred according to both the Variance Ratio Criterion and cluster interpretability. Two of the three clusters correlated highly with clusters retrieved in the original study (r = 0.78, r = 0.71), while the third cluster showed partial resemblance (correlation of r = 0.31). Clusters were named "In Control," "Depressed and Disabled," and "High Deniers and Somatizisers." No differences were found on the physical pathology scores between clusters. Decision rules for cluster assignation resulted in 68% of the sample being correctly assigned. Support for this cluster model from two countries suggests its value in providing a multidimensional picture of patients with chronic low back pain. The possibility of using such cluster groups for determining treatment type is discussed.

Denial mechanisms in myocardial infarction: Their relations with psychological variables and short-term outcome

From a selected sample of 97 males suffering from a first myocardial infarction, 67 patients were studied to ascertain the influence of denial mechanisms (DM) on their cardiological and psychological outcome. There were no differences among high deniers and low deniers with respect to the cardiological outcome, but high deniers showed less anxiety and depressive reactions both in the coronary unit and 1 month later, and also presented less psychopathology in general. In the last evaluation, one year after leaving the hospital ( N = 52), there was no difference among deniers and non deniers in demand for psychiatric attention.

Defensive coping and blood pressure reactivity in medical patients.

Two defensive coping styles, denial of illness and repressive coping, were studied in two groups of medical patients whose blood pressure (BP) was measured during a stress interview. Denial of illness was measured using the Levine Denial of Illness Scale (LDIS), and repressive coping was measured using a combination of the Marlowe-Crowne (MC) Social Desirability Scale and the SCL-90R anxiety subscale (ANX). Consistent with our prior research indicating that LDIS was associated with adaptive outcomes in the short run, high deniers manifested reduced systolic BP reactivity compared to low deniers. Although not related to repressive coping, systolic BP reactivity was correlated positively with MC and ANX separately. The results demonstrate that LDIS and MC measure different types of defensive coping. Current theories of the MC scale suggest two possible interpretations of the MC findings, one that focuses on avoidant coping and the second on attentional coping in high MC scorers.

Denial and medical outcome in unstable angina.

Denial may be adaptive during hospitalization for acute coronary disease. We studied the impact of denial in 48 patients referred to a tertiary care center for treatment of unstable angina. Using the Hackett-Cassem Denial Scale, we divided the group into 25 high deniers and 23 low deniers. The two groups were comparable in baseline demographic and social data, coronary risk factors, cardiac history, medical treatment, vital signs, and cardiac catheterization results (number of diseased vessels and ejection fraction). Compared to low deniers, high deniers had half as many episodes of angina during hospitalization (1.3 vs. 2.5; p less than 0.03, t = 2.2, df = 46) and were more likely to reach medical stabilization, i.e., pain free for 36 hr (92% vs. 65%, p less than 0.03, Fisher exact probability test). Intravenous nitroglycerin drips were also required less often in high deniers (32% vs. 78%, p = 0.002, Fisher exact). Two myocardial infarctions and one death occurred, all in low deniers. We conclude that denial independently predicts better medical outcome during acute hospitalization for unstable angina.

The role of denial in recovery from coronary heart disease.

This longitudinal study investigated the relationship between denial of illness and the course of recovery in patients with coronary heart disease. Using a newly developed interview instrument, the Levine Denial of Illness Scale (LDIS), the level and modes of denial were assessed in 45 male patients who were hospitalized for myocardial infarction or for coronary bypass surgery, of whom 30 were followed for 1 year after discharge. The reliability, internal consistency, and validity of the LDIS were found to be satisfactory. Furthermore, the LDIS showed discriminant validity from trait measures of denial. LDIS scores were not associated with severity of illness or risk factors. High deniers spent fewer days in intensive care and had fewer signs of cardiac dysfunction during their hospitalization relative to low deniers. However, in the year following discharge, high deniers adapted more poorly than low deniers: high deniers were more noncompliant with medical recommendations and required more days of rehospitalization. The findings suggest that denial of illness is adaptive during acute hospital recovery, but is maladaptive in the long-run after hospital discharge.

The Influence of Processing Variables on the Properties of Flocked Fabrics

The effect of 16 variables of the dc electrostatic flocking process has been investigated in a two-level factorial screening experiment. Properties examined include mass and number of fibers sifted, mass and number of fibers flocked, percent of available fibers flocked, percent of theoretical maximum packing density, and abrasion resistance of flocked fabric. The 16 independent variables included six machine variables (voltage, electrode separation, sifter speed and screen mesh, flocking time, and substrate vibration), three flock variables (fiber type, length, and denier), five adhesive variables (adhesive type, concentration, viscosity, thickness, and drying conditions), ambient humidity, and substrate (polyethylene film and aluminum foil). Only the three flock variables and the voltage were found to influence the properties of the flocked fabric. The quantity of fiber sifted was affected by the fiber denier and length and by the sifter speed, but the sifter speed did not influence the flocked fabric. The packing density of the flock on the fabrics ranged from 0.4 percent of the theoretical maximum (for low denier, long length nylon fiber flocked in a low electric field) to 13 percent (for high denier, short length nylon flocked in a high electric field). Of all the variables studied, fiber length had the greatest effect on the flocking properties; increasing the fiber length decreased the number of fibers sifted, number of fibers flocked, and percent of maximum flock density.

Heat Transfer in False-Twist Texturing

A mathematical model for the heating of yarn in the false-twist texturizing process was formed, and an equation for the surface temperature of the yarn for contact-type heaters was derived. An expression for the temperature distribution in the cross section of the yarn in the heater zone was derived mathematically. The surface temperatures of nylon and polyester yarns of different deniers were measured and compared with predicted values. For measuring the surface temperature, a Fiber-temp® non-contact-type temperature measuring instrument was used. The yarns were heated using controlled short heaters 12 in. and 8 in. long. The temperature distribution in the cross section of the yarns was calculated from the equation for various yarn speeds and heater temperatures. The temperature difference between the surface and the center of the yarn was found to be small for the normal yarns used in texturizing, even at very high speeds. Polyester yarns were found to heat up faster than nylon yarns due to the lower heat capacity of polyester. The heavy denier yarns were heated more slowly than the lower denier yarns because of the lower A/M (surface area/mass) ratio of the high denier ones.

The Effect of Construction on Certain Stress-Strain Properties of Uncoated and Coated Fortisan Fabrics

The stress-strain properties of 135 systematically varied Fortisan filament fabrics were investigated before and after coating with rubber and after controlled flexing of the coated fabrics. In the uncoated fabrics, the highest tenacity was attained in a wide range of fabrics which were neither too dense nor too sleazy and which had few yarns of relatively high denier rather than many low denier yarns per inch. The structural tenacity (breaking load of the coated fabrics in the warp or filling direction divided by the weight of the uncoated warp or filling) of the coated fabrics followed roughly the same pattern, but was more sensitive to sleaziness. The range of coated fabrics which retained comparatively high structural tenacity after flexing was limited to those woven with the lowest denier yarns with a combination of a high number of yarns per inch and a rather open weave (2/2, 4/2, 5/1, or 4/4 twill ) or a lower number of yarns per inch and a denser weave, such as 2/1 twill or 4 shaft sateen.

Part II: Effect of Construction on Crease Recovery of Fortisan Fabrics

An attempt has been made to establish some general relationships between crease recovery and variables of fabric construction by an investigation of 174 systematically varied Fortisan filament fabrics. Crease recovery is generally improved by open con struction, i.e., for any one fabric weight, by employment of high yarn denier and wide yarn spacing, and of open weave, i.e., one with long floats. In the case of asymmetrical weaves (e.g., 2/1 or 5/1 twills) the crease recovery is higher when measured with the longer float outside the crease. In general, little effect on crease recovery was found if the yarn properties were varied only in the filling direction.