Paper bags are becoming more and more popular in food packaging. The material of paper plays a very important role. Common ones include white cardboard paper and kraft paper. What is the difference between these two types of paper?
First, let’s talk about white cardboard paper.
White cardboard paper
White cardboard paper is a high-quality white cardboard paper with a smooth surface and high strength. Its main use is to produce color printed matter, such as books, magazines, picture albums, etc. The advantages of white cardboard paper include:
High printing quality:
The white cardboard paper has a smooth surface, good ink absorption performance, and good graphics and text printing effects, which can ensure bright colors, delicate patterns, and clear lines in the printed matter.
White cardboard paper is usually printed using offset printing, letterpress printing and digital printing. Among them, offset printing is suitable for large-volume printing and can show a very high degree of color reproduction; letterpress printing is suitable for printing patterns with clear fonts and fine lines; digital printing is suitable for small batches, multiple varieties, and fast delivery needs. The high whiteness and good smoothness of white cardboard paper allow it to present clear and bright color effects. At the same time, white cardboard paper has strong ink absorption, which allows the pigment to be firmly attached to the paper, thus presenting a very delicate and three-dimensional printing effect. In short, white cardboard paper is an excellent printing material and widely used. By choosing suitable printing methods and solving printing problems, we can effectively improve the printing effect of white cardboard paper and bring better products to designers, printers and consumers in different industries.
Uniform paper thickness
The paper thickness of white cardboard paper is relatively uniform, which can ensure the stability and overall beauty of the printed matter.
Moderate cost: Compared with other high-quality white cardboard, the cost of white cardboard paper is relatively moderate and is widely used.
There are two main disadvantages of white cardboard paper:
1. Easy to absorb moisture: White cardboard paper has strong hygroscopicity and is sensitive to changes in environmental humidity. It is easy to deform or lose its original characteristics.
2. Easily damaged: Although white cardboard paper has a certain strength, it is still easier to damage than other materials. It may not be durable enough for printed matter that needs to bear heavy objects or needs to be bent.
Kraft paper
Kraft paper is a waterproof, oil-proof, and abrasion-resistant material. Due to its special physical properties, kraft paper is widely used in packaging, protection, and decorative products. Its good performance in its functions include:
Packaging: Kraft paper can be used to package various products, such as food, medicine, cosmetics, etc., by folding, wrapping, etc.
Protection: Since kraft paper is waterproof, oil-proof, and wear-resistant, it can be used to protect products, such as preventing water, oil and other contamination, wear and tear, etc.
Decoration: Kraft paper comes in a variety of colors and textures and can be used to decorate various products, such as gift packaging, home decoration, book covers, etc.
But in terms of printing, kraft paper will be more difficult. Since kraft paper itself has a brown background, it will be difficult to print if the printing color and content are highlighted. Common printing methods include the following:
offset printing and gravure printing
The offset printing and gravure printing of kraft paper is suitable for printing large quantities of products. The two kinds of printing method generally uses four-color printing, namely cyan, magenta, yellow, and black. Each color can be generated by mixing these four colors. In offset printing and gravure printing , a film needs to be made, which is then placed on a press and transferred layer by layer.
Digital Printing
Digital printing is a printing method suitable for small batch printing. In digital printing, a digital printing machine is required to print the pattern directly onto kraft paper through computer control. This printing method is fast and accurate, while also ensuring cheap printing and color accuracy.
Screen printing
Screen printing is a printing method suitable for printing partial patterns or text. In screen printing, a template needs to be made, then placed on the screen-printing machine, coated with printing ink, and then kraft paper is placed under the template to print layer by layer.
In summary, the above three printing methods are suitable for color printing on kraft paper. For mass printing, offset printing and digital printing are obviously more suitable; for printing local patterns or text, we can choose screen printing.
White cardboard paper and kraft paper are two commonly used paper materials, each with their own advantages and disadvantages. White cardboard paper is mainly used in the printing field and is widely used because of its high printing quality, uniform paper thickness and moderate cost; while kraft paper is mainly used in packaging, protection and decorative products and other fields because of its waterproof, oil-proof and wear-resistant properties. It is popular for its characteristics such as loss.