Why so much for color printing plastic bag copperplate fee?

Why so much for color printing plastic bag copperplate fee? Many are in the plastic bag manufacturers purchase color plastic bags, manufacturers in addition to the prices of plastic bags, and charging extra for a printed sheet, if the color is more and more complex, copper cost thousands of the same is normal. So why do color printing plastic bags copper so expensive? In the prices of plastic bags, coin fee is usually not taken into account, because when you do a batch of goods, the cost of apportion is so many, but as do the goods batch more and more, share prices will reduce, but can't guarantee, also do next order it's meaningless to the contribution, so are generally will print fee separately. Print there are generally two kinds of printing, called an offset, also known as flexo, another is the copper plate, also called intaglio. Offset is the use of resin production, and the size of production and printing, and the copper plate is must to do machine can hold on the width of the large steel roller, nature price is relatively high. Copper plate is the steel plate to produce roller bag again after a layer of copper plate, finally a layer of chromium plating on metal, and then made for laser engraving, so the price is quite high. So the same a copper plate, why some manufacturer is close 700 some manufacturer is 500? Be sure to color version? Plastic packaging printing copper questions why some manufacturer copper fee is high, some manufacturer copperplate fee low? Some packaging manufacturer copperplate fee is high, some plastic bags manufacturer copperplate fee is low, what reason is this? This is because the plastic bag manufacturers choose different cooperation of copper plate manufacturer, copper plate is divided into quality price, cheap and easy to produce the effect of the copper plate printed sawtooth burrs, and expensive copper plate is not prone to this problem, because the use of the accuracy of plate making equipment. Can tell the difference in durability, cheap version might do less than one million plastic bags have to redo a version, while expensive version LiangSanBaiWanGe can seal bag, this is the gap between the quality. Last century, the overseas import plate-making equipment used to hundreds of millions of yuan to buy, and now millions of MTK is capable of producing copper plate, however, there is a technical barriers, so that different manufacturers according to their own consider to choose different plate making factory, this is why some manufacturers of plastic packaging printing copper plate is more expensive. Printing halftone: must be a color a copper plate? Is a color printing is usually a version, but when the printing pattern color is more complex, such as printing of portrait and so on, a variety of colors mixed together, this need only four CMYK print edition, the depth of the four colors overlap, can produce color and delicate graphics like photos. Of course four version in general is not enough, in other parts of the big piece or use the color printing effect will be better. Therefore, printing design is more complex, generally will not more than 10 copper plate, only 6 - in more Between 8, of course, there are special circumstances to do 12 version only. Printing halftone: ENDPE/PO/PP/PVC/CPE/PPE/OPP/EVA