Vacuum packaging is a common airtight container in our life, so we all know that vacuum packaging bags are generally transparent, but also due to various factors lead to the quality of transparency. Today, Jinan plastic bags from the small series to tell you about the impact of the transparency of vacuum plastic bags what are the factors, right?

一、配胶上的问题

1、 Problems in dispensing

不适当的配胶程序将导致主剂与固化剂不能充分混合均匀。可能产生“胶粒”现象。

Improper mixing procedure will lead to insufficient mixing of main agent and curing agent. May produce "colloidal particles" phenomenon.

二、胶黏剂本身颜色深

2、 The adhesive itself is dark in color

胶黏剂本身颜色太深，深黄色、黄红色，有时甚使酱油汤那样的暗红色，留在胶膜上也是相应的颜色。因此，在要求高透明度的场合下，要选用微黄色甚无色的高透明度的胶黏剂。

The color of the adhesive itself is too dark, dark yellow, yellow red, sometimes even dark red like soy sauce soup, which is also the corresponding color on the adhesive film. Therefore, in the case of requiring high transparency, we should choose yellowish or even colorless high transparency adhesive.

三、基材的透明度问题

3、 Transparency of substrate

内层基材表面呈现“鲨鱼皮”、“流道痕”、晶点等表观质量问题时，将严重影响复合产品的透明度。印刷时转移到非图文部分的雾状油墨版污，也明显影响复合膜的透明度。

The transparency of composite products will be seriously affected when the surface of inner substrate presents some apparent quality problems, such as "shark skin", "runner mark", crystal point and so on. When printing, the haze ink stains transferred to non graphic parts also significantly affect the transparency of the composite film.

四、烘道温度设定不当

4、 Improper setting of oven temperature

一开始进入烘道时的温度太高，干燥太快，使胶液层表面的溶剂迅速蒸发，造成表面层胶液浓度的局部提高，表面结皮，当热量深入到胶液层内部后，皮膜下面的溶剂汽化，冲破胶膜，形成火山喷口那样的环状物，一圈一圈的，也使胶层不均匀，也称“橘皮状”。

At the beginning, the temperature is too high and the drying speed is too fast when entering the drying channel, which makes the solvent on the surface of the glue layer evaporate rapidly, resulting in the local increase of the glue concentration on the surface layer and the surface crusting. When the heat goes deep into the inner part of the glue layer, the solvent under the film vaporizes, breaks through the glue film and forms a ring like a volcanic vent, which also makes the glue layer uneven, also known as "orange peel".

因此烘道温度自入口到出口处应逐步提高，由低到高，有一个梯度，让溶剂有秩序地连续地由内部向外部蒸发。另外，上胶量过大时，胶层在干燥过程中也相对容易产生上述胶层缺陷。

Therefore, the temperature of the drying channel should be gradually increased from the inlet to the outlet, with a gradient from low to high, so that the solvent can evaporate continuously from the inside to the outside orderly. In addition, when the amount of glue is too large, the adhesive layer is relatively easy to produce the above defects in the drying process.