Watermark paper in the manufacturing process, watermark paper can be made into paper by using the marks and patterns required by technical means. These patterns are not easy to see under normal circumstances and can be seen only against the light. Banknotes, important documents, facility drawings and various tickets in most countries are also printed with watermark paper. It integrates design, mold carving and network making in manufacturing, In complex technological processes such as paper making, checking watermark is also one of the effective means to identify true and false.

包裝印刷有疊影便是用一塊印刷版印出來的圖象錯移，在印數上可以見到雙向、三重的圖影。有疊影的緣故有多種多樣，例如打印紙張，叼牙、滾桶、絲印油墨、印速、印刷油墨黏度等多種要素比較復雜，一般能夠選用下列好多個方式來查驗緣故并解決。防復制印刷紙這種紙張復印后，會浮現“復制”和“無效”的字樣，可有效防止彩色復印重要文件，另一種全吸收型防復印紙外觀呈藍色或棕紅色，紙上圖文只有透過光才能看到，其復印件一片漆黑。

There is overlap in packaging printing, that is, the image printed with a printing plate is shifted wrongly, and two-way and triple image shadow can be seen in the number of prints. There are many reasons for overlapping, such as printing paper, teeth, barrel, silk screen printing ink, printing speed, printing ink viscosity and other factors are complex. Generally, the following methods can be used to check the reasons and solve them. Anti copy printing paper after copying, the words "copy" and "invalid" will appear, which can effectively prevent color copying of important documents. The appearance of another full absorption anti copy paper is blue or brownish red. The pictures and texts on the paper can be seen only through light, and the copies are dark.

封套紙張通常選用250g或300g等較厚的紙張。紙張類型可選擇銅版/啞粉紙，卡紙或藝術紙等紙張類型可選擇銅版/啞粉紙，卡紙或藝術紙等。

The envelope paper is usually 250g or 300g thick paper. The paper type can be coated / matte paper, cardboard or art paper. The paper type can be coated / matte paper, cardboard or art paper.

1、紙張說明：銅版紙是常用的封套用紙，手感厚實，給人一種穩重感，適合各類商務使用。

1. Paper Description: coated paper is a commonly used envelope paper. It feels thick and gives people a sense of stability. It is suitable for all kinds of business.

2、紙張克重：250克、300克、350克、400克。

2. Weight of paper: 250g, 300g, 350g, 400g.

3、優點：進口銅版紙，防汗防潮，不易粘灰塵，色彩還原度更好，適合各種顏色。

3. Advantages: imported coated paper, sweat proof and moisture-proof, not easy to stick to dust, better color reduction, suitable for all kinds of colors.

4、缺點：幾乎沒有什么缺點。

4. Disadvantages: there are few disadvantages.

5、設計要求：顏色豐富或有大面積色塊的封套設計圖。

5. Design requirements: envelope design drawings with rich colors or large color blocks.