涂料遮盖力测试操作程序

八戒

SCOPE AND LIMITATIONS使用范围和限制
This procedure is written for the operation of the holding power test ,according to the national standard GB1726-79.
本程序仅针对于涂料遮盖力的测试操作，依据国家标准GB1726-79.
PROCEDURE操作程序

材料和仪器设备
Material and instrument:

漆刷：宽25-35mm
Brush:25-35mm width天平：感量为0.01克，0.001克
Balance: to 0.01g or 0.001 g definition.
黑白玻璃板：100×250×1.2～2mm
Black and white glass panel: 100×250×1.2～2mm
灯箱
Light box

1.
Adjust the viscosity to the product standard viscosity. If the viscosity is too high to brush , reduce the viscosity to the adaptable by adding solvent. But the solvent quantity should be deducted in the holding power calculation.

调整至产品标准规定的粘度,如粘度稠无法涂刷，则将试样调至涂刷的粘度，但稀释剂用量在计算遮盖力时应扣除。

2.
Weight the cup of the testing sample and brush on the balance 0.01g definition as W1.

在感量为0.01克天平上称出盛有油漆的杯子和漆刷的总重量 W1。

3.
Brush the coating on the black-white glass panel in uniformity, and incline the panel 30～45º in the distance 15-20cm with the milling glass piece in the light box. It is end the black-white case is covered under one or two daylight lamp.

用漆刷将油漆均匀地涂刷于玻璃黑白格板上，放在暗箱内，距离磨砂玻璃片15-20cm,有黑白格地一端与水平倾斜成30～45º，在1支和2支日光灯下观察，以都刚看不见黑白格为终点。

4.
Weight the used cup and brush as W2.

将盛有余漆地杯子和漆刷称重 W2，求出黑白格板上油漆重量。

5.
Brush should be quickly and uniformity, and not to touch the panel edge.

涂刷时应快速均匀，不应将油漆刷在板地边缘。

6.
Calculate expressions:

Holing power X (g/m²) calculate expression followed:

X=(W1-W2)/S×10000=50(W1-W2)

Repeat test and average the results. The single result between average shouldn’t be over 5%, If not, test again.

计算公式：

遮盖力X(克/米²)按下列公式计算（以湿膜计）

X=(W1-W2)/S×10000=50(W1-W2)

平行测试两次，结果之差不大于平均值的5％，则取平均值，否则必须重新试验。