• Journal of Digital Convergence
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• v.16 no.12
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• pp.593-602
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• 2018

The purpose of this study was to investigate the coloring properties of non-mordant dyes by examining local literature on silk fabric dyeing using red-colored natural dyes. Natural dyes can be prepared from the following 8 materials: purple-fleshed sweet potato, Impatiens balsamina, mulberry, fruits of Ligustrum japonicum Thunb, guava leaves, dansam, hibiscus flowers, and pruned branches of Prunus persica. To examine the surface color calculated $L^*$, $a^*$, $b^*$, ${\Delta}E^*$, and K/S value and H V/C. The variables considered in the dyeing experiment were dye concentration, dyeing temperature, dyeing time, and number of dyeing iterations, which were varied to evaluate the dyeing properties and color characteristics. As a result, the abovementioned variables, dye affinity, and red color expression were directly proportional to one another. In this study, it was found that red coloring can be obtained with natural dyes; moreover, excellent dyeing was achieved without the need for repeated dyeing or mordanting processes, which cause environmental pollution.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.12
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• pp.1754-1760
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• 2007

To improve poor dye uptake of safflower yellow colorants, cellulose fibers were pretreated with chitosan. The effect of chitosan pretreatment on the dyeability of safflower yellow colorants to cotton, ramie, and rayon was investigated in terms of dye uptake, color, and colorfastness. Irrespective of fiber types, dye uptake increased continuously with increase in chitosan concentration. Chitosan pretreatment improved dye uptake up to 5.6 times for cotton, 7.2 times for ramie, and 3.7 times for rayon. For cotton and ramie, the shade of dyed fabric changed YR color to Y color with increase in chitosan concentration. Dyed rayon fabrics showed Y color irrespective of chitosan concentration. Shades got darker and deeper with increasing chitosan concentration. Shades of chitosan pretreated fabrics were shifted differently depending on dyeing temperature within same fabrics. In common, the color of all dyed fabrics changed to YR at 50 and $70^{\circ}C$ while Y color at 30 and $90^{\circ}C$. V and C value decreased with increase in dyeing temperature and resulted in darker and duller color, in general. Light fastness was fair while washing fastness was poor. It was confirmed that ultrasonic dyeing method enhanced dye uptake more than 30% for cotton and ramie fabrics compared to the conventional automatic machine dyeing method. However, no difference in dye uptake between two dyeing methods was found for rayon.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.12
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• pp.1963-1970
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• 2008

Natural indigo dye in powder form was prepared by modifying traditional Niram method, using $Ca(OH)_2$ instead of baked oyster powder for precipitating indigo dye. The prepared dye was applied to dyeing Tencel fabrics to investigate the effect of experimental conditions for the optimization of dyeing process. The indigo dye powder contained 15.2%(w/w) of indigo content and 0.757%(w/w) of indirubin content on the basis of HPLC analysis. Maximum dye uptake was obtained at $60^{\circ}C$ for 20min. Almost saturated dye uptake was obtained at 2g/L of sodium hydrosulfite concentration up to 4g/L of indigo dye and then slowly increased for further increase of sodium hydrosulfite. Whereas at higher indigo dye concentration(8g/L) more than 3g/L of reducing agent concentration was required for obtaining the maximum dye uptake. At the same indigo dye and reducing agent concentration, K/S value of the sample dyed without sodium hydroxide(pH 5.75) was 15.19, much higher than one dyed in alkaline condition(K/S 5.76). There was no difference in colorfastness ratings among samples with different color strength. However, more fading was occurred for the sample with low color strength.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.107-107
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• 2012

3종 복합소재인 양모와 나일론, 레이온의 염색공정은 먼저 알칼리 욕에서 반응성염료로 레이온을 염색한 후, 산성욕에서 산성염료로 양모와 나일론을 염색하는 것이 일반적이다. 그런데 양모, 나일론, 레이온은 알칼리에 민감하므로 면 염색 시 적용되는 강알칼리인 수산화나트륨을 사용하면 섬유의 취화로 인하여 강도와 촉감저하 등의 문제가 발생하게 된다. 따라서 본 연구에서는 알칼리 중 탄산나트륨과 중탄산나트륨을 사용하여 염료를 투입하지 않고 염색공정을 거친 후 백도와 인장강도를 측정하여 황변 및 강도 변화 여부를 알아보았다. 레이온 70%, 양모 19%, 나일론 11%의 혼용율을 가지는 전처리 된 편물(130$g/m^2$, 32 inch, 18 gauge)에 탄산나트륨(시약 1급) 20g/l과 중탄산나트륨(시약 1급) 20g/l 각각을 투입하고 반응성염색공정($60^{\circ}C$, 60 min)으로 처리한 경우와 반응성 염색 후 산성염색공정($98^{\circ}C$, 60 min)으로 처리한 경우로 나누어 측색을 통해 백도와 L, a, b값을 측정하고 KS K 0521에 따라 인장강도 시험을 실시하였다. 그 결과, 탄산나트륨 투입시 백도 값이 중탄산나트륨에 비해 10% 정도 낮아지고 L, a, b값도 상대적으로 yellow 방향으로 이동해 있는 것으로 나타났다. 이것은 황변이 일어남을 의미하며 육안으로 확인하였다. 또한 인장강도 측정결과를 통해 소다회 처리 시 중조에 비해 30% 정도의 강도 저하가 일어남을 확인할 수 있었다. 그러나 반응성염색 후 산성염색을 거치게 되면 황변과 강도 저하 현상이 회복되는 경향을 나타내었다. 즉, 천연/나일론 편물을 반응성염색 시 알칼리로 탄산나트륨을 사용하면 염색공정 상에서 중탄산나트륨에 비해 황변이 일어나 염료 고유의 색상 발현에 영향을 줄 수 있고 강도 또한 30% 정도 저하되지만, 후에 산성염색 공정을 거치면 산 조건과 욕중 효과를 통해 일부 개선됨을 확인하였다. 이와 별도로 이번에는 시판되는 반응성염료 5종과 산성염료 3종을 조합하여 탄산나트륨과 중탄산나트륨 투입에 따른 염색실험을 실시하고 측색(DataColor SF600 광원D65, Strength)을 통해 염착량을 비교하였다. 그 결과, 중탄산나트륨으로 염색하면 탄산나트륨에 비해 모두 염착량이 저하되었으며, 염료의 구조적 차이와 컬러별로도 그 차이는 다양하였다. 그 중 저온에너지형 반응성염료는 탄산나트륨 투입에 비해 47~60% 정도로 가장 양호하였으며, 일부 반응성염료는 20%까지 떨어지는 값을 나타내었다. 이것은 탄산나트륨보다 중탄산나트륨의 알칼리 정도가 낮으므로 반응성염료의 염착이 적은 것으로 생각되며, 저에너지형 반응성염료의 경우에는 낮은 온도나 알칼리 조건에서도 상대적으로 높은 고착률을 나타내므로 적절한 반응성염료의 선택을 통해 그 차이를 극복할 수 있을 것으로 사료된다. 이상의 결과를 통해 탄산나트륨과 중탄산트륨의 알칼리 정도가 강도와 염착량에 미치는 영향의 차이를 고려하여 최적의 현장 처방을 선정해야 함을 알 수 있었다.

• Journal of the Korean Wood Science and Technology
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• v.35 no.3
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• pp.70-78
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• 2007

This study explored the efficient dyeing method of aged chestnut wood using the natural dyes extracted from Gardenia jasminoides for, grandiflora, Carthamus tinctorius L., Rhus javanica L., Lithospermum erythrorhizon S. et Z., Caesalpinia sappan L. and Castanea crenata S. et Z.. The color variation of the dyed chestnut woods was also quantitatively evaluated. The wood specimens revealed abundant colors through different dyeing conditions such as dyeing temperature, dye pH, soaking time, and brushing frequency. The chroma and stain concentration of colored woods were calculated with $L^*$, $a^*$ and $b^*$ in order to make color tone measurement. Brushing treatment for colored wood was confirmed as a more economical dyeing method than soaking treatment requiring more time when natural dyeing was done. Furthermore, the desirable tone and shade of color was easily obtained by repetitive brushing treatment using low color tone. During natural dyeing, good color expression was made with high temperature and acidic condition of a dyeing liquor.

• Science of Emotion and Sensibility
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• v.19 no.4
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• pp.3-12
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• 2016

The aim of this study is to find the optimal combination dyeing condition for the enhancement of dye uptake and union dyeing of the composite material fabric made of triacetate and quick drying PET blended yarn. For the experiment, fabrics were one-bath combination dyed using the mixed dye of E-type disperse dye(C.I Disperse red 50) and S-type disperse dye(C.I. Disperse red 92) to measure dyed fabric's dye exhaustion, dye uptake, color and color difference according to the diverse conditions including dying temperature, time and mixed ratio of the dye. Dye equilibrium of combination dyeing occurred in $100^{\circ}C$, but by comparing dyed fabrics' K/S value and surface color, it was found that $120^{\circ}C$ was where the manifestation of color of triacetate and quick drying PET was identical. Mixed dye exhaustion and dye uptake merely changed as dyeing time increased, but color became more uniform. Therefore, it can be concluded that by using combination dyeing method, and by using the mixed dye which the mixing ratio of S-type dye and E-type dye is appropriately controlled, dye uptake can be improved compared to using single dyeing regardless of the color of E-type dye.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.6
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• pp.928-934
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• 2008

The objective of this study is to investigate the dyeing properties of safflower yellow dye on silk for the standardization of dyeing process and color reproducibility. Yellow colorants were water-extracted from safflower petals, concentrated, and freeze-dried to obtain colorants powder. The effects of dye concentration, dyeing temperature, and pH of dye bath were studied in terms of dye uptake and shade. Fastness to dry cleaning and light was evaluated. Dye uptake increased with raising temperature and brighter and more vivid yellow shade was obtained when dyed at $30^{\circ}C$. As colorants concentration increased, dye uptake increased progressively and the shade got darker and deeper. Maximum color strength was obtained at pH 3.5. It was speculated that the adsorption of colorants seemed to occur mainly by hydrogen bonding and physical force at pH 5.5 and by ionic bonding as well as hydrogen bonding below isoelectric point(pH 3.8-4.0). The results of reproducibility test showed acceptable color difference in the range of $1.11{\sim}2.01$. Washing fastness was fairly good as 4/5 rating, while light fastness was 2/3 rating.

• Journal of Sericultural and Entomological Science
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• v.28 no.1
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• pp.72-78
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• 1986

The studies were performed to investigate the optimum conditions for tannic processing of silk by use Chinese Gallotannin and synthesized tannic acid, which are aimed at weighting, dyeing and physical properties of tannin treated silk. 1. It was reasonable that the concentration of tannin solution is 30 grams per liter of Chinese Gallotannin, 15 grams per liter of tannic acid for the efficient weighting of processed silk. The temperature and time for tannin treatment was optimum at 80$^{\circ}C$, 60 minutes and the acidity of tannin solution at pH 2 to 3. 2. In dyeing the tannintreated silk by Acid dye Orange II, the temperature and time was reasonable at 60$^{\circ}C$, 90 minutes to control the desorption of tannin components weighted onto silk. 3. The colour differences ($\Delta$E) of dyed silk fabric by soaping could be remarkably narrowed by tannin treatment, resulting in improving the washing fastness of tannin treated silk by two grades more than that of untreated one. 4. The light fastness of tannin treated silk could be drastically improved by reducing the dye-loss of dyed silk fabric which was coused from the Ultra-violet ray irrdiation. 5. The rubbing fastness and water repellency of tannin treated silk was at the same level with that of untreated one. However, the Drape coefficient of tannin treated silk was decreased more than that of untreated one, which is closely related with fabric softness and dressing appearence.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.532-540
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• 2019

PET microfibers with various diameters (0.5, 0.2, 0.06, and 0.01 dpf) were dyed with a dispersed dye (C.I. Disperse Blue 56) at various temperatures. The dyeing process was conducted under infinite dyebath conditions at constant temperatures. The effects of the dyeing temperature and diameter on the partition coefficient, affinity, and diffusion coefficient of disperse dyes were studied. The curve of isotherms was fitted well to Nernst-type model in a large range of initial dye concentrations. At the same temperature, the partition coefficient and affinity decreased with increasing sample diameter due to the increase in surface area. At all deniers, the partition coefficient and affinity decreased with increasing temperature because the dyeing process is an exothermic reaction. In addition, the decrease in radius of the sample gives rise to a decrease in the heat of dyeing. The fine diameter of the sample resulted in an increased surface area but decreased space between the microfibers. Consequently, decreasing the diameter of the microfibers leads to a decrease in the diffusion coefficient. At the same diameter, the diffusion coefficient increased with increasing temperature because of rapid dye movement and the large free volume of the sample inside. In addition, thermal dependence of the diffusion coefficient increased when the diameter of the sample increased.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.23-32
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• 2020

This study investigated the thermal degradation and fading behavior of PTT dyed with vat dye and its dyeing ability. The PTT sample was dyed with vat dye using an acid treatment and pad-steam method to improve the dyeing performance. This method made dye particle nanosize and allowed it to penetrate the polymer material easily. The sample dyed using the pad-steam method showed level dyeing and enhanced dyeing affinity, compared to the batch-dyeing method. The degradation behavior of PTT dyed with vat dye after each heat and UV treatment was examined with the change in tensile strength or K/S value on the sample. The tensile strength and K/S values of the sample dyed with vat dye after the heat and UV treatment decreased with increasing temperature and exposure time. Although they showed high degradation under severe conditions, its rate constant was improved compared to the samples dyed with disperse dye. Consequently, acid treatment and the pad-steam method resulted in the introduction of vat dye on PTT. In addition, the PTT dyed with vat dye showed enhanced thermal and UV resistance because of their high molecular weight and chemical structure for stable adsorption behavior.