본 연구는 실내 공기오염에 대한 관심이 증가하고 있으며 분말형 흡착재를 첨가한 수성도료의 시공성(점도, 표면박리)문제를 개선하기 위해 입상형 흡착재를 사용한 수성도료의 특성을 검토하였다. 우선, 입상형 활성백토의 첨가율에 따른 특성을 검토하기 위해 점도(낙하시간), 건조시간(완전건조), VOCs 농도 잔여율, 내알칼리성 및 내충격성을 검토하여 입상형 활성백토의 적정 첨가율을 도출하고자 하였다. 앞서 실시한 실험으로 도출되었던 입상형 활성백토의 적정 첨가율을 기반으로하여, 입상형 활성백토의 입자크기에 따른 수성도료의 특성을 검토하고자 점도(낙하시간), 건조시간(완전건조), VOCs 농도 잔여율, 내알칼리성 및 내충격성을 측정한다. 따라서, 입상형 활성백토의 첨가율과 입자크기에 따른 수성도료의 연구 범위 내에서는 다음과 같이 요약하였다.


1. 입상형 활성백토의 첨가율에 따른 수성도료의 특성 검토
입상형 활성백토의 첨가율에 따른 수성도료의 특성을 검토하였다. 입상형 활성백토의 첨가율이 증가할수록 점도(낙하시간)는 증가하였다. 건조시간(완전건조)은 입상형 활성백토의 첨가율이 증가할수록 동일한 시간이 측정되면서 차이가 없었다. VOCs 농도 잔여율은 입상형 활성백토의 첨가율이 증가할수록 감소되었다. 내알칼리성은 입상형 활성백토의 첨가율이 증가할수록 육안으로 관찰하였을 때에는 변색의 정도가 약간 감소하였다. 그러나, 색차분석을 실시한 결과에서 L*값의 차이는 입상형 활성백토의 첨가율에 따라 차이가 나지만 a*값과 b*값의 차이는 미비하다. 따라서, 입상형 활성백토의 첨가율이 증가할수록 내알칼리성이 향상되지 않는다고 판단된다. 내충격성은 입상형 활성백토의 첨가율이 증가할수록 타격 부분의 패임이 식별되었으며 패임의 평균 크기는 감소하였다. 그러나, 패임 평균 크기의 감소하는 폭은 약 1mm이하로 도출됨에 따라 충격에 대한 저항성이 미약하게 향상되었다고 판단된다.

2. 입상형 활성백토의 입자크기에 따른 수성도료의 특성 검토
이전 실험을 기반으로 입상형 활성백토의 첨가율을 20%로 선정하고 입상형 활성백토의 입자크기에 따른 수성도료의 특성을 검토하였다. 이는 실험항목 모두 고려하여 입상형 활성백토의 첨가율이 50%가 적합하다고 판단되었지만 입상형 활성백토의 입자크기별로 점도(낙하시간)를 시험하였을 때 측정이 불가하였기 때문이다.
이에 따른 결과, 입상형 활성백토의 입자크기가 커질수록 점도(낙하시간)는 감소하였다. 건조시간(완전건조)은 동일한 시간이 측정되면서 차이가 없었다. VOCs 농도 잔여율은 입상형 활성백토의 입자크기가 커질수록 증가되었다. 내알칼리성은 육안으로 관찰하였을 때, 입상형 활성백토의 입자크기가 커질수록 석회수를 담근 경계 부근에서만 변색이 발견되었다. 그러나, 색차분석을 실시한 결과에서 L*값의 차이는 입상형 활성백토의 입자크기에 따라 차이가 나지만 a*값과 b*값의 차이는 미비하다. 따라서, 입상형 활성백토의 입자크기가 커질수록 내알칼리성이 향상되지 않는다고 판단된다. 내충격성은 입상형 활성백토의 입자크기가 커질수록 타격 부분의 패임이 식별되었다.


결론적으로, 본 연구에서 사용된 입상형 활성백토를 사용한 수성도료의 특성을 검토한 결과 입상형 활성백토의 첨가율은 20%가 적합하다. 이를 기반으로 하여 입상형 활성백토의 입자크기에 따른 적정 입자크기는 0.250mm가 적합하다. 따라서, 입상형 활성백토의 적정 첨가율과 적정 입자크기를 사용한다면 실내 공기질을 개선시킬 수 있을 뿐만 아니라 시공성 문제도 해결될 수 있다고 판단되며 실제 도료로써 활용이 가능하다고 사료된다.

This study evaluates the properties of water-based paints added granular adsorbents to improve the workability (viscosity, surface peeling) problems of water-based paints with powdered adsorbents, as interest in indoor air pollution is increasing. First, in order to evaluate the properties by changing addition rate of granular activated clay, the appropriate addition rate of granular activated clay is selected by examining viscosity (fall time), drying time (complete drying), residual rate of VOCs concentraten, alkali resistance and impact resistance. Based on the appropriate addition rate of granular activated clay derived from the previous experiment, viscosity (fall time), drying time (complete drying), residual rate of VOCs concentraten, alkali resistance and impact resistance are measured to examine the properties of the water-based paint by particle size of granular activated clay. Therefore, it is summarized as follows within the research scope of water-based paint by changing addition rate and particle size of granular activated clay.


1. Evaluation of water-based paint by changing addition rate of granular activated clay
Properties of water-based paints by changing addition rate of granular activated clay were evaluated. As the addition rate of granular activated clay increased, the viscosity (fall time) increased. There was no difference in drying time (complete drying) as the same time was measured as the addition rate of granular activated clay increased. The residual rate of VOCs concentraten decreased as the addition rate of granular activated clay increased. As for alkali resistance, the degree of discoloration decreased slightly when observed with the naked eye as the addition rate of granular activated clay increased. However, in the results of color difference analysis, the difference in L* value differs depending on the addition rate of granular activated clay, but the difference between a* value and b* value is insignificant. Therefore, it is judged that the alkali resistance does not improve as the addition rate of granular activated clay increases. As for the impact resistance, as the addition rate of granular activated clay increased, the dents in the striking part were identified, and the average size of the dents decreased. However, as the decreasing width of the average size of the dent was derived to be less than about 1mm, it is judged that the resistance to impact was slightly improved.

2. Evaluation of water-based paint by changing particle size of granular activated clay
Based on the previous experiment, the addition rate of granular activated clay was selected as 20%, and the properties of water-based paint by changing particle size of granular activated clay were evaluated. This is because 50% of the addition rate of the granular activated clay was considered appropriate considering all the experimental items, but it was impossible to measure when the viscosity (fall time) was tested for each particle size of the granular activated clay. As a result, as the particle size of granular activated clay increased, the viscosity (fall time) decreased. There was no difference in drying time (complete drying) as the same time was measured. The residual rate of VOCs concentraten increased as the particle size of granular activated clay increased. When the alkali resistance was observed with the naked eye, as the particle size of granular activated clay increased, discoloration was distinguished only near the boundary immersed in lime water. However, in the results of color difference analysis, the difference in L* value differs depending on the particle size of granular activated clay, but the difference between a* value and b* value is insignificant. Therefore, it is judged that alkali resistance does not improve as the particle size of granular activated clay increases. As for the impact resistance, as the particle size of the granular activated clay increased, the dents in the striking part were observed.


In conclusion, as a result of evaluating the properties of the water-based paint added granular activated clay in this study, 20% of the addition rate of granular activated clay is suitable. Based on this, the appropriate particle size by changing particle size of granular activated clay is 0.250mm. Therefore, it is judged that if an appropriate addition rate and appropriate particle size of granular activated clay are added, not only can the indoor air quality be improved, but also the workability problem can be improved, and it is judged that it can be used as an actual paint.