• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.11a
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• pp.9-14
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• 2006

Deinking is a series of unit operations designed to detach ink from cellulose fibers and separate the dispersed ink from the pulp slurry. Deinking chemicals are process aids that enable expensive mill equipment used in these unit operations to operate more efficiently. This paper presents an overview of ONP deinking efficiency with cellulolytic enzymes and synthetic collector in low alkalinity process. The deinking efficiency of old news print even in low alkalinity condition was enhanced with enzyme contained complex agent. The brightness of deinked pulp was increased with less residual ink particles and yield of deinked pulp was improved compared to the deinked pulp of conventional alkaline method.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.149-152
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• 1999

A new process for deinking of colored offset newsprint, i.e. enzyme treatment in cooperation with ultrasonic wave was developed in the present study. The physical characteristics such as fiber length, coarseness, crystallinity index of the deinked pulps were investigated and the sugar residues released from the treatment were analyzed. It was found that colored offset newsprint could be deinked effectively by cellulase treatment when ultrasonic wave was applied. The brightness increased by 5% ISO over that of control experiment and the pigment content was reduced markedly. Though the ultrasonic wave had little effect on the strength and crystallinity of the pulp, the treatment of enzyme combined with ultrasonic wave reduced the coarseness and fiber length to some extent. It was also found that ultrasonic wave could accelerate the hydrolysis of cellulose and hemicellulose during the cellulase treatment.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.10a
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• pp.271-277
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• 2011

Recently increasing eco-efficiency of natural dyeing has become an important topic. The purpose of this study was to manufacture colored pulp for interior materials by combining color therapy and natural dyeing. For this purpose, through experiments with water-bleed, K/S value and chroma changes of samples in pulp for interior materials.

• Journal of Forest and Environmental Science
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• v.29 no.2
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• pp.125-130
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• 2013

An attempt was made on pulp production from the fast growing plant, Acacia hybrid to determine the total yield, screened yield, Kappa number, and fibre morphology of organosolv Acacia hybrid pulp. Uniform-sized chips were taken to undergo pulping in a digester with five different concentrations of ethanol, 50%, 60%, 70%, 80% and 90% (v/v) with 1 M of sodium hydroxide as catalyst. All chips were digested in a temperature-controlled digester with constant amount of water added and temperature of $185^{\circ}C$ with the duration of three hours cooking time and correspond pressure 1.1-1.2 MPa. It was observed that increasing of ethanol concentration has led to pulp yield increment and decreased in the degree of delignification at the same time. This study was aimed to focus on the effect of the varied concentration of organic solvent towards the pulp yield and its relationship with Kappa number and pulp yield.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.727-730
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• 2003

Electric pulp test is a method to examine the vitality of dental pulp using the electrical stimulation. During the pulp test, the current stimulates intradental nerve, and makes patients painful. Some studies were accomplished to measure the responses of subjects by stimulating over the sensory threshold. In this study, we examined the time delay between pain feeling and stimulation stop in clinical situation. And we measured the activated responses(EMG in anterior belly of digastric muscle, voice, and finger span). As a result, it was verified that the minimum and maximum delay was EMG and voice, respectively. By reducing the excessive stimulus time, the unnecessary pain can be minimized using EMG that has the minimum delay.

• Journal of the Korean Wood Science and Technology
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• v.25 no.4
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• pp.45-50
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• 1997

This research was studied for dissolving pulp preparation as the raw material of viscose rayon from woody biomass by solvolysis pretreatment. In the change of pulp characteristic after solvolysis pretreatment, the following results were obtained. In the case of solvolysis pretreatment, we have obtained pulp that high purity cellulose, and degree of polymerization was inclined to decrease less than 440 on the phosphoric acid as catalyst. Comparing phosphoric acid and formic acid as catalyst in the solvolysis pretreatment, using on formic acid catalyst is superior to phosphoric acid catalyst for making dissolving pulp.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.5 s.113
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• pp.15-24
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• 2005

Different types of antioxidants compounds were prepared economically from natural sources. Application of these compounds towards photo stabilization of high yield bagasse pulp has been investigated. It was found that potato peel antioxidant followed by clove volatile oil provides lower brightness reversion and better photo stabilization effect for paper made from high yield bagasse pulp after exposure to UV lights in comparison with butyl hydroxy anisol or chamomile volatile oil.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.5 s.113
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• pp.56-62
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• 2005

The catalytic effect of molybdovandophosphate heteropolyanion (HPAs) on the delignification of kraft bagasse pulp by hydrogen peroxide has been investigated. Very small amounts of the catalyst (0.05 0.3 mM/l) gave convenient results. Partial reduction of the catalyst was also studied. The effect of reaction medium (water, ethyl alcohol and acetone) on the bleaching was also studied. The results obtained show that the optimum condition for bleaching in presence of polyoxometalate were 0.05 mM/l catalyst concentration at $70^{\circ}C$ reaction temperature and $7\%$ consistency at pH 2 in aqueous medium. The ratio of water to solvent of 60:40 from acetone gives higher brightness than ethyl alcohol. The catalyst solution can be reused for 5 times without any reduction in brightness. ESR for the blank and exhausted solutions under different conditions was also carried out to find the relation between reduced metals and pulp brightness.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.1
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• pp.9-14
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• 2008

Beating and using chemical agents are common methods to improve physical properties. But the beating is high energy consumption process and chemical agent addition may cause deteriorate waste water quality. Therefore, it is necessary to use more environment-friendly methods. In this study, micro pulp was used in the handsheet making to get improving effects of physical properties without beating treatment and chemicals. Stiffness, thickness and air permeability were increased and strength properties of paper were also improved to some extents by only the micro pulp addition.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.11a
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• pp.261-268
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• 2007