Earticle

산화전분을 골판지 구성원지인 표면라이너지와 이면라이너지에 각각 코팅하였으며 산화전분 코팅에 따른 골판지의 물성변화를 조사, 산화전분 코팅의 효과를 분석한 결과는 다음과 같았다. 산화전분의 코팅에 의해 골판지의 수직압축강도 뿐만아니라 파열강도도 동시에 개선될 수 있었다. 골판지의 파열강도는 구성 라이너지의 처리면에 관계없이 일정수준의 도공량에 도달할 때까지 크게 증가하다가 그 이상에서는 더 이상의 증가를 보이지 않았다. 표면라이너지에 처리한 골판지의 경우 도공하지 않은 골판지의 파열강도에 비해 도공량이 $2.32g/m^2$일 때 30.3%가 증가하였고 이면라이너지에 처리한 경우 도공량이 $4.84g/m^2$일 때 36.8%가 증가하였으며 표면라이너지와 이면라이너지 모두 처리한 경우 도공량이 $7.16g/m^2$일 때 39.9%가 증가하였다. 산화전분의 코팅은 골판지 원지의 섬유간 결합을 증가시키는데 기여하고 강직성을 개선시켜 골판지 수직압축강도의 개선을 가져왔다. 구성 라이너지의 처리면에 관계없이 골판지의 수직압축강도는 산화전분 도공에 의해 전반적으로 증가하였는데, 이면 라이너지에 처리한 경우 도공량이 $1.58g/m^2$일 때 11.3%가 증가하였고, 표면라이너지와 이면라이너지 모두 처리한 경우 도공량이 $2.99g/m^2$일 때 11.9%가 증가되어 소량의 산화전분 도공에 의해서도 수직압축강도가 크게 개선되었다.

Coating was carried out on liner components of B flute, single-wall corrugated board (SK180/S 120/K2(0) to examine the effect of liner component coatings by oxidized starch on the properties of corrugated board. Both bursting strength and edgewise compression strength(ECS) of corrugated board were improved by coating of its liner components with oxidized starch. Bursting strength of corrugated board rapidly increased with an initial increase of coating weight, but as the coating weight further increased, there was no increase in bursting strength. The results showed 30.3% improvement for 2.32g/m2 coating on outside liner component, 36.8% improvement for 4.84g/m2 coating on inside liner component and 39.9% improvement for 7.16g/m2 coating on both liner components in bursting strength of corrugated board. Regardless of treated liner components, ECS of corrugated board was improved by coating of oxidized starch, and especially greater improvement was accomplished when corrugated board was coated on inside liner component or both liner components at low level of coating weight - 11.3% improvement for 1.58g/m2 coating on inside liner component and 11.9% improvement for 2.99g/m2 coating on both liner components.

개발한 EPS 포장상자가 농산물의 신선도 유지효과 기능이 있는지의 여부를 분석코자 배를 포장하여 20℃에 저장하면서 골판지상자와 0.02와 0.04mm 두께의 LDPE필름으로 포장한 것들과 신선도 유지효과를 비교하였다. 저장 50일 후 중량 감소는 대조구는 4.4%, EPS 상자는 0.7%의 중량감소가 나타났고, 비타민C도 2.12와 2.63 mg%로 EPS 포장구가 20% 높게 유지되고 있었다. 당도와 산도는 포장구간에 큰 차이가 있었으며 부패는 대조구는 상자당 1-2개과가 발생했으나 EPS 포장구는 발생하지 않아 개발한 EPS 포장구를 신선도 유지를 위한 유통용 상자로 활용가능성이 확인되었다.

Weight loss of pear packed with corrugated paperboard box after 50 days storage at 20℃ was 4.4%, and those of 20LD, 40LD film and EPS box were 0.8-0.7%. Ascorbic acid content of EPS was 20% higher than that of control. Hardness of EPS was also similar trend. Titratable acid and total soluble solid content of pear were not different among the packages. Decay of control was 1-2 pieces per box, but the others was not found. Overall appearences of LD, CE and EPS were better than that of control.

개발한 EPS 포장상자가 오이의 신선도 유지효과 기능이 있는지의 여부를 분석코자 오이를 골판지상자와 0.02와 0.04mm 두께의 LDPE필름으로 포장 20℃에 저장하면서 신선도 유지효과를 비교하였다. 저장 7일후 중량감소는 대조구는 4.9%, EPS 상자는 0.8%의 중량감소가 나타났고, 경도는 대조구 보다 필름구와 EPS 포장구에서 높았으며 비타민C도 EPS 포장구가 대조구 보다 15% 높게 유지되고 있었고 클로로필 함량은 EPS 포장구가 대조구 보다 21% 높게 유지되고 있었다. 부패는 포장구간에 나타나지 않았으며 대조구에서 표면이 노랗게 변하였으나 필름구와 EPS에서는 변하지 않았다 EPS 포장상자는 신선도 유지효과가 기존의 골판지상자 보다 더 우수하였다.

Weight loss of cucumber packed with corrugated paperboard box after 7 days storage at 20oC was 4.9%, and those of 20LD, 40LD film and EPS box were 0.8, 0.7, and 0.8%. Total ascorbic acid content of EPS was 15% higher than that of control. Hardness of EPS was also similar trend. Chlorophil content of cucumber packed with EPS box was 21% higher than that of control. Decay of control was 1-2 pieces per box, but the others was not found. Overall appearence of LD, EPS was better than that of control.

인쇄하지 않은 복사용지에 대해 침지, 탈수, 건조등 일련의 리사이클링 사이클의 반복횟수에 따라 얻어지는 재생지의 광학적 성질의 변화와, 리사이클링 횟수를 달리한 펄프를 이용하여 고지를 제조한 후 하여 고지의 탈묵성 변화를 살펴보았다. 그 결과, 리사이클링 횟수 증가에 따라 얻어진 재생지의 백색도는 원래보다 약10% 저하되었으나, 섬유간 결합감소에 따른 비산란계수의 증가로 불투명도는 약10%정도 증가하는 경향을 보였다. 또한, 리사이클링 횟수에 따른 고지의 탈묵성은 섬유의 표면 자유에너지 감소, 즉 섬유의 소수화 증가로 인하여 약간 저하되는 것으로 나타났다.

This study examined the effects of recycling on chemical pulp fibers from multiple recycles. Firstly, water-pretreated alkaline photocopy paper was disintegrated by TAPPI standard disintegrator at room temperature. After dewatering, this pulp was dried in oven at 80℃ for 24hrs. A sequence of wetting, disintegrating and drying was one recycling cycle and this cyclic treatment was repeated from zero to five times. The recycled handsheet dropped to 90% of the original brightness after five cycles, and lost the most brightness in the first two cycles. However, it had a gain of 10% in opacity after five cycles. And, in this study, the method for determining residual ink(toner) content in recycled handsheets were estabilished by means of SEM-EDX and atomic absorptive photometer. The change of residual ink percentage on recycled paper showed the effect of recycling numbers on deinkability of waste paper. A slight decrease in deinkability was noted for the recycled handsheets, which may be due to the change of fiber surface free energy connected with fiber swelling.

일반골판지 상자에 고무판인쇄를 하는데 있어서 바코드 인쇄 정밀도에는 필름 마스터의 정밀도와 적정축소율이 매우 중요하며, 현장에서의 판독률 향상요인으로는 스캐너를 포함한 완벽한 시스템의 구성이 필요하다. 필름마스터에는 입력된 바코드번호를 변환기로 변환하여 인화현상기로 필름을 제작하는 것이 정밀도가 좋았으며 축소율은 BWR 100이 BWR 200보다 양호하였다. 또한 바코드를 판독하는데 있어서 omni directional scanner type이 99.5%이상의 판독률을 나타내어 목표치인 판독률 99.8% 이상의 완벽한 시스템구성 가능할 것으로 기대된다.

In point of flexographic printing on generally corrugated fiberboard cartons, the precision of film master and the adequate compression rate are very important factor in bar-code printing. Also, the complete system including scanner is essential for the purpose of enhancing the reading rate. The film master had good precision when the film was prepared by means of printing/developing machine after transformation of input bar-code number through transceiver, and the BWR 100 showed better compression rate than BWR 200. Also considering the bar-code reading, the complete system targeting the reading rate above 99.8% could be configured by Omni-Directional Scanner type accomplishing the reading rate above 99.5%.

We used recording device(EDR-3) to monitor the packages and the vehicle during shipment. Provided we did this enough times, we began to gain statistically valid information which could be used to describe the particular channel of distribution. The event was obviously changed from trip to trip, but in general we could have an idea of what to expect. Considerable amount of time and money were invested to record field data. Although not ideal, it was the best suited approach to gain information regarding a specific distribution channel. Based on the recorded field data, we could make our own packaging vibration testing specification through MIL-STD-810D(Guidance for development of laboratory dynamic test specification). This test specification was proved several times through field tests. As a result, we gained confidence in this revised vibration specification and come to know the development procedures of a laboratory dynamic test specification.

Immature and mature plums(Prunus salicina L.) were coated with calcium-added methylcellulose(CaMC) and hydroxypropylmethyl-cellulose-15(CaHPMC-15). Physicochemical, nutritional and sensory characteristics were compared during the 8-day storage period at 30℃. Irrespective of maturity, pH of plums increased and the titratable acidity decreased during storage. Free sugars such as glucose, fructose, sucrose and sorbitol were eventually decreased during storage, but Ca-added cellulose coatings influenced on the prevention of free sugars from decreasing especially in mature plums. Vitamin C contents in immature and mature plums became decreased during storage, but the coatings took effective on its retention. Changes of malic acid, the major organic acid in plums were appeared the same tendency as vitamin C during storage. Results of sensory evaluation showed the development of red color in peel and the softening of plum tissue, and also showed that the overall eating quality and appearance generally decreased during storage. However, the coated plums either CaMC or CaHPMC-15 exhibited the better sensory characteristics. As though the significant difference in postharvest storage quality were not found between the two coatings, CaMC and CaHPMC-15 coatings significantly contributed to the improvement of overall storage quality, especially the retention of vitamin C and organic acids only on the mature plums.