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、配膠上的問題

1、 Problems in dispensing

不適當(dāng)?shù)呐淠z程序?qū)?dǎo)致主劑與固化劑不能充分混合均勻?？赡墚a(chǎn)生“膠粒”現(xiàn)象。

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

二、膠黏劑本身顏色深

2、 The adhesive itself is dark in color

膠黏劑本身顏色太深，深黃色、黃紅色，有時(shí)甚使醬油湯那樣的暗紅色，留在膠膜上也是相應(yīng)的顏色。因此，在要求高透明度的場(chǎng)合下，要選用微黃色甚無(wú)色的高透明度的膠黏劑。

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、基材的透明度問題

3、 Transparency of substrate

內(nèi)層基材表面呈現(xiàn)“鯊魚皮”、“流道痕”、晶點(diǎn)等表觀質(zhì)量問題時(shí)，將嚴(yán)重影響復(fù)合產(chǎn)品的透明度。印刷時(shí)轉(zhuǎn)移到非圖文部分的霧狀油墨版污，也明顯影響復(fù)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、烘道溫度設(shè)定不當(dāng)

4、 Improper setting of oven temperature

一開始進(jìn)入烘道時(shí)的溫度太高，干燥太快，使膠液層表面的溶劑迅速蒸發(fā)，造成表面層膠液濃度的局部提高，表面結(jié)皮，當(dāng)熱量深入到膠液層內(nèi)部后，皮膜下面的溶劑汽化，沖破膠膜，形成火山噴口那樣的環(huán)狀物，一圈一圈的，也使膠層不均勻，也稱“橘皮狀”。

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".

因此烘道溫度自入口到出口處應(yīng)逐步提高，由低到高，有一個(gè)梯度，讓溶劑有秩序地連續(xù)地由內(nèi)部向外部蒸發(fā)。另外，上膠量過大時(shí)，膠層在干燥過程中也相對(duì)容易產(chǎn)生上述膠層缺陷。

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.