Talk about the types and characteristics of stapled cardboard

As the bones of the book case, the cardboard has a close and close relationship with the processing effects of books, such as its thickness, tightness, flatness, moisture content, and strength. Therefore, the type, function, and quality of the cardboard are well understood and accurately selected. Cardboard suitable for each type of processing needs is often important for producing high quality products. Cardboard refers to a paper product that is thicker, heavier, and stiffer than paper, generally quantifying over 400g/m2. There are six kinds of binding board thickness: 0.7mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, etc. The thickness of the commonly used book shell board is 1.5-2.5mm.

Types of bound cardboard after printing Cardboard refers to a paper product that is thicker, heavier, and stiffer than paper, and generally has a basis weight of 400 g/m2 or more. There are six kinds of binding board thickness: 0.7mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, etc. The thickness of the commonly used book shell board is 1.5-2.5mm.

The type and function of binding paperboard

There are three kinds of common paperboard for binding, namely, gray board, grass board and yellow board.

1 gray board white paper

Gray-white board paper, also known as bookcase cardboard, is a type of cardboard that is designated as a book cover in the national industry standard. Since the late 1970s, it has been applied to the production of book shells, and the effect is good. It has been used up to now. The gray-white board paper is made of multi-layer (usually three-layer) structure made of groundwood pulp, semi-chemical wood pulp, straw pulp and the same waste pulp. The gray-white paper surface is smooth (calendered) and suitable for making all kinds of book cases.

Gray-white board paper is currently the most widely used type of cardboard for making book cases and folders. Because this kind of paperboard's material selection and production requirements are relatively strict, it has the advantages of proper water content, small elongation, good elasticity, proper tightness, smooth surface, and not easily deformed after being glued. This is a processing unit for books and periodicals. It was favored and was identified as a special cardboard for the book case.

At present, there are many manufacturers producing gray-white board in China, but the quality of the products is still not enough. The surface of the board is often uneven, with excessive moisture content, large thickness tolerances, and weak layers (cutting and delaminating). Problems such as binding to the binding process have caused great trouble. Although the quality of products has improved in recent years, but the impact of foreign import cardboard is still inevitable. In order to ensure the smooth progress of processing, the following points should be observed when using gray-white board.

(1) According to the grade of the workpiece, choose the appropriate grade of cardboard, and choose the appropriate thickness according to the thickness of the book, the size of the format, etc.

(2) When the water content of the board purchased in winter is too large, do not rush to use the material. Store it for a period of time to allow it to evaporate naturally and use it after the ambient humidity reaches a balance. Do not dry after drying. This will cause the size of the bookcase to shrink and prevent it from fitting with the book block.

(3) When using the automatic hot stamping machine, if it is found that the tolerance of the paperboard thickness is large, it must be checked and selected beforehand, and the thickness may be roughly divided. It may also be processed by a manual hot stamping machine.

(4) When the material was found, the paperboard layer was not firmly bonded (stratified). At this time, it should not be cut into small sizes, nor should it be used for medium-diameter paperboards. After the bookcases were made of paperboard paste with weak interlayers, The appearance of unevenness, convexity, warping, etc., affects the appearance of books. Gray whiteboard paper format is generally 1100mm × 800mm, 1350mm × 920mm and several other types, using the flat form of packaging, each piece weight does not exceed 250kg.

2. Grass cardboard

Grass board is also called horse dung paper board. Its surface is rough and yellow, and the main raw material is straw fiber. Grass cardboard is a kind of binding cardboard used earlier in our country, and it is also a kind of cardboard that is widely used. The thickness of grass board is generally 0.7mm, and the thickness can be increased after twisting. This kind of cardboard has low tightness, high elongation, poor toughness, strong permeability and exudation ability on the surface, and easy warpage due to moisture penetration after the glue is glued, but its low price can be used for processing low-grade book shells. Because the raw material and processing technology of the cardboard are different from those of the gray-white board, the following points should be noted when using this cardboard as a book cover.

(1) Do not hurry to use after buying grass cardboard. Store it for a period of time to make it smooth and obtrusive.

(2) When it comes to wet paperboard, it must be stored for a period of time so that it can be naturally dried to a certain extent before use. If there is a premise, before use, use a pressure board machine to heat (heating temperature is generally around 65°C) and pressurize to make the rough surface of grass paperboard smooth, tight and with proper humidity (retain the internal water in the fair). .

(3) When the book shell is pasted, apply a binder with less moisture, fast drying, and good viscosity, and improve the scouring process so that the sealing force (sealing 2 and sealing 3) is greater than the sealing force and avoids post-processing. The book shell warps outward.

(4) When making a book cover with a size of 16 or more pages, it should be lined with a single liner in order to achieve a balance of greater surface tension.

The width of grassboard is generally 1092mm×787mm, 787mm×660mm, and 787mm×546mm, and it is packaged in the form of a flat plate. The weight of each piece is generally not more than 150kg.

The quality of grass paperboard is lower than that of gray paperboard, but its price is low. It is used for general medium and low-grade books. As long as the scientific method is used in the process, the quality can be guaranteed.

3. Yellow cardboard

Yellow cardboard is a kind of cardboard which is smoke-brown (the same color as kraft paper), with smooth surface, hard texture, and high toughness. It is commonly used for shoes (doing hall bottom) and box making (internal bones). When binding, it is mainly used for the manufacture of book outer envelopes and department book envelopes. The outer envelopes made of yellow cardboard are durable and not easily worn, and can protect books and improve the quality of books. Because of its high tightness and small thickness error, it is also conducive to grasping the hot stamping pressure. There are two main forms of outer envelopes for making books with yellow cardboard: one is using yellow cardboard to indent and die-cut and then directly paste into the envelope; the other is to make a layer of paper or fabric on the surface after making the envelope. Material, used to decorate the appearance of the envelope. The following points should be noted in the processing when making shells and sleeves.

(1) The yellow cardboard is hard and has high toughness. Once warping and deforming is difficult to correct, the press or stacking method is applied after the shell to give a certain pressure to prevent warping and deformation of the book case.

(2) Yellow board hardness, suitable for hot embossed imprints, and strong and durable deformation, but the stamping pressure is greater than other cardboard.

(3) When finishing the lining of the finished product, it is necessary to make the sealing pull greater than the external pull, so as to prevent the upward pull of the book shell from warping upwards and it is not easy to level.

The yellow cardboard is generally 1350mm x 920mm, 1120mm x 990mm, etc., and is packaged in a flat plate. Each piece weighs no more than 250kg.

Card type and function

Jam is a kind of paper product with a thickness between the paper and the cardboard. Its basis weight is generally between 250 and 400 g/m2. There are two kinds of cardboard: one is a double-sided white card, and the other is a gray card (white on the surface and gray on the bottom).

Gray card

Grey card is also called single-sided grey cardboard. It consists of three layers: the surface is white, smooth and flat, and can be printed; the middle layer is a filler layer, and the raw materials are poor; the bottom layer is gray and relatively rough. The gray card texture is soft, thin, crisp, and resistant to folding, and the bottom layer is hygroscopic. It is commonly used in various kinds of packing boxes. After compounding, it can be used as a stamp album, CD sleeve, etc.

Stapling uses this material mainly for the processing of soft bookcases, looper liners, slipcovers, medium-diameter cardboard, and bookbacks.

Gray card should note the following points when binding.

(1) When making soft shells, appropriate adhesives should be selected according to the material to be adhered to prevent stickiness or deformation.

(2) When using a flat-lock adhesive-backed paper jam, soak it in hot water for about 10 hours before use so that the paper is soaked and soft. Then use a small amount of animal bone in the soaking water to prevent cutting. When raising the hair line).

(3) When the looper is hard-linered, the bottom surface should be glued to the ring lining. Because the bottom surface is rough, strong infiltration and exudation, and easy to bond the paper, the surface can be exposed to make the book block and the cover seal processing ( Insert sets).

(4) When used in the book shell medium diameter cardboard, it should be noted that it is limited to the circular back cover shell, it is not suitable for the back ridge, should be exposed on the surface of the plastic surface.

(5) When the gray card is used for compounding, attention should be paid to the selection of the adhesive and the accuracy of the smearing and gluing process, so as to ensure that the composite product is flat and clean and firmly separated.

2. White card (double white)

The white card is higher than the gray card, and the white card is composed of three layers: the surface layer and the bottom layer are white, smooth and flat, and can be used for double-sided printing; the middle layer is a filler layer and the raw materials are poor. The white card texture is relatively hard, thin and crisp, and has a wide range of uses, such as various high-grade packaging boxes, cigarette cases, cups, and children's books. The binding white card is mainly used for soft-faced book cases, paperback covers, imitation sheets, and hard linings.

Cardboard storage and storage

Accurate storage and storage of cardboard (including cardboard) is one of the most important factors in guaranteeing the quality of books and books.

Storage requirements

Cardboard should be stored in a well-ventilated warehouse or workshop with proper temperature and humidity. Paperboard must not be exposed to moisture so as to avoid deformation or aging separation. It must not be placed in the open air. Because the paperboard itself needs to maintain its internal fair moisture, if the paperboard is exposed to the sun for a long time and the heating is baked, the normal moisture will evaporate, and the fibers will change. Brittleness, reduced strength, resulting in surface warpage, causing unnecessary losses.

2. Storage method

Purchased cardboard must first understand the date of production, the time of manufacture is short and is made by cold pressing method. It cannot be used immediately. It must be stored for a period of time before use. Because the newly-purchased paperboard is generally more flexible and less flexible, after being stored for a certain period of time through fairways, the paperboard can reduce the toughness of the paperboard, increase the flexibility, and make the flat clothes neat and easy to process. The time for storing cardboard is generally 3 to 6 months. If the cardboard is stored for more than 1 year, it is necessary to carry out a stockpile to balance the moisture content of the cardboard stack. When storing, you should also pay attention to the accumulation of cardboard on the paper table, and avoid direct contact with the ground.