Diskuse s uživatelem:Chinaprinting4u: Porovnání verzí

Řádek 305: Řádek 305:
 
(2) The hardness of yellow cardboard is high, suitable for hot stamping embossing marks, and it is firm and durable without deformation, but the hot stamping pressure is larger than other cardboards.
 
(2) The hardness of yellow cardboard is high, suitable for hot stamping embossing marks, and it is firm and durable without deformation, but the hot stamping pressure is larger than other cardboards.
 
(3) When processing the finished lining, be sure to make the inner pull force greater than the outer pull force to prevent the outer pull force from being too large to prevent the book case from warping upward and being difficult to level.
 
(3) When processing the finished lining, be sure to make the inner pull force greater than the outer pull force to prevent the outer pull force from being too large to prevent the book case from warping upward and being difficult to level.
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== What Cause Board Book Warping And Deforming? ==
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Board book warping and deforming is a common technical problem encountered by [https://www.chinaprinting4u.com/Board_Book_Printing_65.htm '''board book printers'''].
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Board books include hardcover books with gray boards as bookcases and books mounted with cardboard with a weight of 200-250 grams per square meter. They are very common in book printing companies and are prone to quality problems such as warping and deforming.
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What cause board book warping and deforming?
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1. Raw materials
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The structure of the gray board or cardboard itself determines that it is easier to warp and deform during board book printing. Gray board or cardboard has high density and long fibers, and its water absorption has a great influence on the structure of board books.
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When absorbing water, the fibers of the gray board or cardboard will stretch, due to gray board or cardboard has a certain thickness, the amount of water absorbed on both sides will be inconsistent, resulting in different elongation lengths of the fibers of the gray board or cardboard, which makes gray board or cardboard deforming.
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At the same time, when water is lost, the fibers of the gray board or cardboard will shrink, but the inconsistent water loss on both sides will cause the fibers to shrink inconsistently, resulting in deformation.
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Although the gray board or cardboard will deform due to water absorption and water loss, the deformation caused by water loss is more serious than water absorption. In addition, different brands and types of gray board or cardboard have different water absorption and deformation extent in custom [https://www.chinaprinting4u.com/Board_Book_Printing_65.htm '''board book printing'''].
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2. Ambient temperature and humidity
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The environmental temperature and humidity have a great influence on the printing board books. When the ambient temperature and humidity are lower than the water content of the cardboard, it will cause the cardboard to lose water, and the degree of water loss in each part of the cardboard is generally different, resulting in warping and deformation of the cardboard.
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When the ambient temperature and humidity are higher than the water content of the cardboard, it will cause the cardboard to absorb water, which will also cause the cardboard to warp and deform.
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The degree of deformation in these two cases are different. The deformation when water is lost is much greater than that when water is absorbed, so the warping deformation of board books always occurs in the dry seasons of autumn and winter.
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3. Production process
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When print a board book, it is necessary to cover or mount with white latex. The white latex contains a lot of water. When the shell is placed or mounted, a large amount of water will enter in the cardboard, but the water does not enter uniformly, which leads to inconsistent moisture content in each part of the cardboard, finally leads to the board books warping and deforming.
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4. Production method
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When [https://www.chinaprinting4u.com/Board_Book_Printing_65.htm '''custom board book'''], some companies use machines to automatically load them, and some companies are artificial shell. Automatic shelling by machines is generally more uniform than the adhesive applied by artificial shell, so that the moisture content of the cardboard is more uniform.
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At the same time, the viscosity of the adhesive used for automatic shelling by machine is different from that of the adhesive used for manual shelling, that is, the solid content of the adhesive is different. The solid content of the adhesive should be high, and the water content should be small, and it is less likely to cause  board book warping and deforming.
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5. Process design
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Whether it is gray board or cardboard, all have textures, so when the board book is shelled or mounted, it needs to be carried out according to the texture. A lot of production experience tells us that for [https://www.chinaprinting4u.com/Board_Book_Printing_65.htm custom board books]'''custom board books''', it is necessary to cover the casing along the grain; for the mounted book, it needs to be mounted along the grain. If it does not follow the grain, the finished cardboard book will have serious warping deformation in the later stage.
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In short,raw materials,ambient temperature and humidity, production process, production method ,process design,these five aspects,which are the mainly factors to cause the board book warping and deforming.In next article,we will focus on how to solve board book warping and deforming.

Verze z 13. 7. 2022, 08:25

                                                3 Eco-friendly Ink For Children’s Book Printing
 
 Recent years,more and more parents like to purchase Eco-friendly children books for their children, which makes children's book printers'Tučný text'https://www.chinaprinting4u.com/ reduce to use ink or use Eco-friendly inks when print children’s book.


 In this article,we will mainly introduce 3 types of eco-friendly ink for children book printing.


 To see whether the ink is an environmentally friendly ink, the following two points are mainly considered:


 1. Heavy metals, due to children's reading habits, heavy metals in ink may be inhaled from the mouth.


 2. Volatile substances, solvents and additives used in ink, include aromatic hydrocarbon, alcohol, etc. They evaporate as the ink dries and enter the reader's respiratory system.


 What types of environmentally friendly inks are included?
 1. Rice bran ink
 Rice bran ink technology originated from Japan. At present, many institutions and book printing companies in chinahttps://www.chinaprinting4u.com/ are studying it. The main reason is that both China and Japan are big countries in rice consumption and production. 


 Without exerting its maximum value, the development of rice bran oil refining technology and the technological breakthrough of rice bran oil in ink not only maximizes the value of rice bran, but also further improves the environmental protection and sustainable development of printing ink.


 The main advantages of rice bran ink are: ink VOC (Volatile Organic Compounds, volatile organic compounds) residue is low, migration is low, and environmental pollution is little; rice bran resources are easy to localize, which is in line with Chinese national conditions; The residue of harmful substances is small and the safety is high.


 However, the development of rice bran ink is also affected by some objective conditions and ink performance defects, mainly including: China's rice bran oil refining and utilization technology is not developed and popularized enough, the scale is not enough, the cost of rice bran oil is relatively high; The drying speed is slow; the application technology of rice bran ink is not popular enough, and the printing operation and control details are not well known, etc.So rice bran ink is not widely used in children's book printing China.


 'Tučný text'2.Soybean ink
 The aromatic hydrocarbons of mineral oil in the ink are reduced or disappeared, but the influence of VOC is still unavoidable. Therefore, some of the mineral oil is replaced by soybean oil in soybean ink. After mildly purifying soybean oil, it is mixed with additives such as pigments and resins.


Soybean inkink has many advantages: scratch resistance, no irritating odor, light and heat resistance, easier to recycle, wide color, etc. In addition to soybean oil, other vegetable oils can also be used, such as linseed oil.


 Now,many printing companies often use the soybean ink to printing children’s books.https://www.chinaprinting4u.com/


3.Water-based ink

 Water-based ink does not contain volatile organic solvents, and only needs to be diluted with water during printing. Therefore, the water-based ink greatly reduces the emission of VOCs and avoids the pollution of volatile organic compounds. At the same time, it significantly reduces the residual hazardous substances on the surface of printed products, and is one of the most environmentally friendly ink types.


In addition, the application of water-based ink can also reduce the fire hazard caused by static electricity and flammable solvents, and reduce the residual solvent odor on the surface of the printed matter.


 Therefore, the application of water-based inks in food packaging, children's board book printing, tobacco and alcohol packaging is becoming more and more common.

What to Consider When Choose Book Printing Paper

 Book printing in chinahttps://www.chinaprinting4u.com/, we always say choosing paper for a book is like finding a partner.Choose the paper for a book determines whether it matches the qualities of the book; in short, whether it can best present the content. 

When we choose the paper,we really need to consider is:how to choose the paper with cost-effective,good printing effect,best fits the book’s content and cheap.

Book printing china.jpg

What are the parts include in choosing paper?
If for the paperback,which includes:
 1. The inner paper;
 2. The end paper.It is the layer of paper between the cover and the text. (Some paperbacks don't use end paper)
 3. Inner cover paper:not every book has it.
 4. Girdle paper: not every book has it, and there are some books, the girdle is part of the outer cover.
 If for the hardcover book printing service,the paper includes:
 1.Inner paper
 2.The end paper
 3.Mounting paper: It is the layer of paper or cloth mounted on the outside of the hard shell (remind everyone to consider the effect of the mounting paper after mounting).
 4.Outer cover paper:not every book has it
 5.Girdle paper: not every book has it.
 When we choose the printing paper,what are we need to consider?
 1.The printing effect.Your book is plain text or with many photos?If your book has many photos,what’s type of the photo.Do you need to see the details clearly, or is there only a general presentation? Is the blur of large particles more effective? Do you pay special attention to the restoration of color, or do you have no special requirements for color.
 2.The gram weight of paper.Paper is generally priced by ton, that is to say, when the price for per ton is the same, you can buy more paper with low gram weight (generally thinner), so it is relatively cheaper, but the gram weight is relatively low. If it is too low, when the paper is printed on the machine, it is easy to wrinkle, and the printing ink, especially double-sided printing, is easy to penetrate, and the effect is very poor.
 As for the high gram weight, the paper is relatively thick (the same kind of paper, regardless of the bulk), and it is thicker in the hand. It is often seen that we custom hardcover book https://www.chinaprinting4u.com/with relatively little content. If the price is relatively high, everyone thinks it is not worth it, but the weight increases. With the same number of pages, the whole book is much thicker, and the price also goes up.
 Special reminder: There are some coated papers, their coating is deep into the paper texture (not only on the surface), this type of paper, the gram weight is more higher, coating is more thicker and the color reproduction is more better ; if the gram weight is lower, it will reduce the coating ability to restore color.
 
 3.The bulk of paper: imagine the paper as a cake. If paper with low bulk is like pancakes, thinner, and paper with high bulk is like a dough cake. So the same gram weight, the book is thicker.
 4.The price of paper.Paper is one of the major costs in china book printing, especially today when the price of paper is rising.
 5.Whether to close or open: the paper used for printing books in chinahttps://www.chinaprinting4u.com/ has a certain size, and the commonly used sizes are different for different papers. During the process of cutting and folding the printing paper into the size of the book, if the size is not correct, it will waste the paper. Such as, before we custom spiral bound book printing, we must fully communicate with the book printing companies in china ,to ask whether this size and the use of this kind of paper will cause waste.

How to choose the paper for your printing project?

In China printing servicechina printing service,select the paper for your printing project is one of the most important parts,which will directly affect the final presentation and the cost of your printed products.

Our commonly used printing paper can be divided into the following night Categories:White cardboard, gray board, coated paper, offset paper, corrugated paper, specialty paper, writing paper, Kraft paper, newsprint,etc.

1. White cardboard:


It is a kind of thick, thick and heavy paper. The surface of this paper is smooth and calendered with high stiffness.

Characteristics: Single-layer or multi-layer combined paper made entirely by bleached chemical pulping and fully sizing, generally the basis weight is above 150g/�? The characteristics of this cardboard are: high smoothness, good stiffness, neat appearance and good formation.

Common weights: white cardboard weights of 200, 250, 300, 350, 400 grams are more commonly used.

Advantages: thick enough and hard enough. The hardness of the cardboard is very high among the paper of the same number of grams. People who like thick cards will really appreciate this paper. The color is not less than coated paper, also very colorful. Writing on the reverse side is easily wiped off immediately. This paper with cost-effective, the price is in the middle.

Disadvantages: It is easy to scratch, from printing to writing, daily touch is very easy to scratch the front very ugly, generally high-grade cardboard will be covered with film to prevent scratches. In particular, black and dark colors will have traces when touched lightly. And irreversible.

Usage:Printing business cards, certificates, invitations, packaging boxes, tags, handbags, covers, monthly desk calendars and postal postcards, etc.

2. Grey cardboard:


Produced from a recycled waste paper. The products are divided into single ash, double ash and full ash, which are environmentally friendly packaging materials.

Usage:packaging boxes, advertising boards, folders, photo frame backboards, luggage, storage boxes, samples, liners, partitions and hardcover book printinghttps://www.chinaprinting4u.com,etc.

3. Coated paper:


Coated paper, is also called coated printing paper. It is a premium printing paper made of base paper coated with white paint. The surface of the paper is smooth, the whiteness is high, the paper fiber is evenly distributed, the thickness is consistent, with small flexibility,good elasticity, strong water resistance and tensile properties. The absorption and reception of ink are very good.

Common classification: Coated paper is divided into single-sided coated paper, double-sided coated paper, matt coated paper, and cloth coated paper. According to the quality is divided into A, B, C three grades.

Common gram weights: The gram weights of coated paper are divide into:70g,80g, 105g, 128g, 157g, 180g, 200g, 230g, 250g, 300g, 400g, 450g, etc. 

Advantages: The color is very bright, the paper is very absorbing, and the color reproduction is high; it can be laminated, and it has a better feel after lamination, and the original material of this paper is very smooth and textured.

Disadvantages: Handwriting is not easy to dry, because it is too smooth.

Usage:Print covers and illustrations of luxury books, color pictures, postcards, picture albums, all kinds of exquisite product advertisements, samples, product packaging, trademarks, etc. Generally, if you want rich colors and complex patterns, coated paper is suggest.

4. Offset paper:


Also known as offset printing paper, double-adhesive paper, etc, it is made of bleached chemical softwood pulp and an appropriate amount of bamboo pulp, and is coated on both sides of the paper with glue. Double-sided coated sizing or calendering, mainly used for lithographic (offset) printing presses or other printing presses to print higher-grade color prints.

Features: It is a relatively high-end paper for book printing in china. It has higher requirements on the ratio, expansion ratio and surface strength during printing. The acidity and alkalinity should also be close to neutral or weakly alkaline.

Common gram weights: offset paper gram weights are divided into 70g, 80g, 100g, 120g, etc., which are more commonly used.

Advantages: offset paper has small elasticity, uniform ink absorption, good smoothness, tight and opaque texture, good whiteness and strong water resistance.

Usage:Printing instructions, sticky notes, colored paper, monochromatic or multi-color book covers, text, inserts, pictorials, maps, posters, color trademarks and various packaging products.

5. corrugated paper:


It is a board-shaped object made of liner and corrugated corrugated paper formed by corrugated stick processing. It is generally divided into two types: single corrugated cardboard and double corrugated cardboard. E, F five types.

Usage:A-type corrugated and B-type corrugated are generally used as outer packaging boxes for transportation, and beer boxes are generally made of B-corrugated. E-corrugated is used for single-piece packaging boxes with high aesthetic requirements. F-type corrugated and G-type corrugated are collectively referred to as micro-corrugated, which is a very thin corrugated. Packaging of microelectronic products such as digital cameras, portable stereos, and refrigerated goods.

6. Specialty paper:


Paper with special purpose and relatively small output. There are many kinds of special paper, which is a general term for all kinds of special-purpose paper or art paper.

The main purpose:

Usage:printing business cards, covers, decorations, handicrafts, boutiques and etc.

7. Kraft paper:


It is a tough and water-resistant packaging paper, brownish-yellow, and has a wide range of uses. The basis weight range is 40 g/m2 to 120 g/m2, in roll and flat paper, as well as single-sided gloss, double-sided gloss and striped. The main quality requirements are flexibility and firmness, high burst resistance, and can withstand greater tension and pressure without breaking.

Usage:printing kraft paper bag,wrapping paper, envelopes,etc.

To summary,choosing the right paper for your project is depend on what type of product you want to print.If you can make the decision,you can ask the book printing factoryhttps://www.chinaprinting4u.com/, who can give you the best professional suggestions for your project. Specialty paper.jpg

How to know the common sense of Chinese printing?

 Prints often appear in our lives, but how much do you know about Chinese printingchinese printing knowledge?

Whether it is promotional albums, books printing, catalogue printingcatalogue printing, brochure printing, or business cards, etc, they are all inseparable from printing. Today, we will help you quickly understand printing knowledge through the two parts of printing method classification and paper classification. Part 1 : How to classify printing method?


Classification of printing methods, which can be divided into:

(1) offset printing, that is, lithographic printing, which is printed on a flat surface, such as paper and self-adhesive;

(2) Embossed printing, also called flexo printing, is generally used in plastic printing; (3) Screen printing, which is what we call universal printing, it can be printed on any object and is very flexible, but it has a disadvantage that it is not suitable for large-scale printing. Part 2 : How to classify printing paper?

Commonly used paper for China printing Paper can be divided into industrial paper, packaging paper, household paper, cultural paper, etc. according to different uses, among which cultural paper includes writing paper, art drawing paper, printing paper, etc. . In the printing paper, according to the performance and characteristics of the paper, it is divided into newsprint, letterpress printing paper, offset printing coated paper, dictionary paper, map and marine drawings, gravure printing paper, painting newspaper, weekly newspaper, whiteboard paper, writing paper, etc. . In addition, some high-end prints also widely use art drawing paper. coated paper (1) Features: smooth surface, high whiteness, uniform distribution of paper fibers, consistent thickness, small stretchability, good elasticity, strong water resistance and tensile properties, and absorption and acceptance of ink Condition is very good. There are two types of coated paper: single-sided and double-sided. (2) Main use: mainly used for printing albums, covers, postcards, exquisite product samples and color trademarks. sublime paper (1) Characteristics: The difference from the coated paper is that the surface of the paper is matte, the paper fibers are evenly distributed, the thickness is good, the density is high, the elasticity is good, and it has strong water resistance and tensile properties. The absorbency and receiving state are slightly lower than that of coated paper, but the thickness is slightly higher than that of coated paper. (2) Main use: mainly used for printing albums, cards, postcards, exquisite product samples, etc.

 White cardboard paper

(1) Features: It is a thick and firm white cardboard. There are two types of yellow core and white core. (2) Main use: It is mainly used for printing business cards, postcards, invitations, certificates and printed matters for packaging and decoration. white board paper (1) Features: The inner core is gray, and the paper is thick and firm. There are two kinds of gray background and white background (2) Main use: It is mainly used for printing materials for various packaging and decoration. Double tape paper (1) Features: Wide application and stable quality. (2) Main use: mainly used for various manuals, envelopes, letterheads, etc. writing paper (1) Features: Writing paper is a paper for ink writing, and the paper is required not to smear when writing. (2) Main use: mainly used for printing exercise books, notepad printing, forms and account books, etc. Kraft paper (1) Features: It has a high tensile force, with single light, double light, stripes, no lines, etc. There are two kinds of white cowhide and yellow cowhide (2) Main use: mainly used for wrapping paper, envelopes, paper bags, etc. art paper (1) Features: There are many kinds. (2) Main use: Mainly used in beautiful book covers, picture albums, cheap brochures printing, invitations, greeting cards, high-end office paper, business cards, high-end packaging paper, etc. Sticker (1) Features: Due to the adhesive on the back, the paper is thinner. Mirror surface, copper plate, writing sticker, etc., and the viscosity is different (2) Main uses: mark labels, postal parcels, letter packaging, transport goods labels, envelope address labels, etc.

How to choose right Chinese printers?

Book printing is something that we must focus on in the business process, so how to choose right book printing companieshttps://www.chinaprinting4u.com when printing our product? Now let's take a look.


1.You need to know your printing requirement.

  No printer in the world can print all types of product.Among all kinds of printing enterprises, the enterprises engaged in printing publications (books, periodicals, newspapers, etc.) account for about the total number of printing enterprises 10% of the total, and about 30% of the enterprises are engaged in packaging and decoration printing materials (trademark logo, advertising, packaging paper, metal, plastic, etc).

The rest are engaged in printing other printed materials (documents, materials, charts, tickets, etc.). According to the above data,although the printing companies are many, but the products who can provide are different. Therefore, before looking for a printing company, you must be clear about your printing requirement, so that we can correctly find the right printing company. Such as if you need a moon cake box, of course, you have to find a color box printing supplier.Printing company can print what products are actually depend on their production equipment. For example, if a newspaper printing factory needs a professional newspaper rotary printing machine;In addition to ordinary printing machines,custom book printing plants also need folding machines, bookbinding (glue binding, horse riding binding, thread binding, etc) equipment and paste mounting equipment; In addition to the printing machine, we also need other post printing processing equipment, such as die-cutting machine (beer machine), bronzing (silver, laser) equipment, laminating machine, UV machine, gluing machine, etc.


2.You need to clear the quality requirements for products

This is also very important. Different quality requirements can determine what kind of suppliers to find. Generally speaking, large-scale company’s product quality will be more guaranteed. Because both the progressiveness of equipment and quality of employees are relatively high. Product quality can be effectively guaranteed also depends on the improvement of management system and complete processing equipment of large-scale manufacturer. It is the latter two points to ensure the long-term stability of product quality. Actually, a large number of manufacturers are small in scale, but their equipment is advanced.The quality of employees is as good as most of large factories. What they lack is perfect management and product processing equipment, which leads to product quality and quantity fluctuates greatly. Therefore, when the product requirements are high, it is necessary to choose large and medium-sized printing factories.


3. You need to know how many to print

The quantity directly affects the selection of printing companies. Such as,if you need to print children’s book for 500 copies, you can choose small and medium-sized printing plants. Because in terms of quantity, we should printing 500 copies of such book is not a problem for most printing company. Both the quality and quantity are very good guarantee. However, if the number rises to 5000 or 10000 copies, we should choose medium-sized or large-scale printing company, because only the large-scale companies have enough production capacity to complete the task according to quality within a certain time. (small printing houses refer to below 100 people, medium-sized refers to more than 100 people but less than 500 people, and large refers to more than 500 people. Note: this classification standard is for reference only)


4. Select printing suppliers according to price affordability.

 As the saying goes, "you get what you pay for" .If the price affordability is not high, you can only find a non famous brand printing manufacturer.There is a big difference in price between famous brands and non famous brands, because brands are intangible values and have a good reputation in quality.


The above are the precautions for us to find right book printing company to custom printing service for your product, I hope it can help you.

Common cardboards for hardcover book printing

There are many materials involved in hardcover book printing. Selecting the appropriate material for the cover processing can not only ensure the smooth progress of the book cover processing process, but also avoid the occurrence of quality problems such as book cover warping. Cardboard is used as the bones of the bookcase, and its thickness, tightness, flatness, moisture content, strength, etc. are closely related to the book processing effect. Knowing the type of cardboard and choosing the cardboard suitable for different processing needs is very important for making high-quality products. There are three kinds of cardboards commonly used in binding in Chinese printing houses, white cardboard with gray background, straw cardboard and yellow cardboard.

1. White cardboard paper with grey background Grey-bottomed whiteboard paper is made of ground wood pulp, semi-chemical wood pulp, straw pulp and the same waste paper pulp in a multi-layer (usually 3-layer) structure. The grey-ground whiteboard paper has a smooth surface (calendered) and is suitable for making all kinds of bookcases. The following points should be paid attention to when using whiteboard paper with gray background. (1) Choose the appropriate cardboard according to the grade of the processed product, and choose the appropriate thickness according to the thickness and size of the booklet. (2) According to the experience of Chinese printers for many years, when the moisture content of the cardboard purchased in winter is too large, do not rush to use it, but store it for a period of time to allow the moisture to naturally volatilize and balance with the ambient humidity before use. Do not dry the material after opening, as this will reduce the size of the bookcase and make it impossible to fit the book block. (3) When processing with an automatic hot stamping machine, if the thickness tolerance of the cardboard is found to be large, it should be checked and selected in advance, and roughly divided according to the thickness, or a manual hot stamping machine can also be used for processing. (4) When it is found that the cardboard is separated from the layer during cutting, it is neither suitable for cutting into small format nor for medium-diameter cardboard, because the cardboard paste that is not strong between the layers will cause uneven appearance, bulging and warping after the book case is made of paste. The phenomenon such as melody affects the appearance quality of the book.

2. Straw cardboard Its surface is rough and yellow, and the main raw material is straw fiber. The thickness of straw board is generally 0.7mm, and the thickness can be increased after lamination. This kind of cardboard has low tightness, high elongation, poor toughness, and strong surface moisture absorption and penetration ability. The following points should be paid attention to when using straw cardboard as a book cover. (1) Do not rush to use the straw cardboard after purchasing it, and store it for a period of time to make it flat and obedient. (2) When encountering damp cardboard, it should be stored for a period of time to allow it to dry naturally to a certain extent before use. If conditions permit, it can be heated with a cardboard press (the heating temperature is generally around 65°C) and pressurized before use, so that the rough surface of the cardboard is flat, the tightness is increased, and the humidity is appropriate (preserve reasonable internal moisture). (3) When pasting the book case, use an adhesive with less moisture, fast drying and good viscosity, and improve the lining process, so that the tension on the inside of the cover (the second and third) is greater than that of the outside, so as to avoid post-printing processing. The bookcase warps outwards. (4) When making bookcases with a size of 16K or above, a single lining should be mounted on the inside of the cover to balance the tension between the inside and outside of the cover.

3. Yellow cardboard Yellow cardboard is a kind of smoky brown (the same color as kraft paper), smooth surface, hard texture and high toughness. It is mainly used for making outer envelopes and some bookcases in bookbinding. The outer cover of the book made of yellow cardboard has good durability and is not easy to wear, which can effectively protect the book and improve the grade of the book. Because of its high tightness and small thickness error, it is also beneficial to control the hot stamping pressure. The following points should be noted when making shells and envelopes. (1) The yellow cardboard is hard and tough, and it is difficult to correct the warpage and deformation. Therefore, after the case is made, a press or stacking method should be applied to give a certain pressure to prevent the warpage and deformation of the bookcase. (2) The hardness of yellow cardboard is high, suitable for hot stamping embossing marks, and it is firm and durable without deformation, but the hot stamping pressure is larger than other cardboards. (3) When processing the finished lining, be sure to make the inner pull force greater than the outer pull force to prevent the outer pull force from being too large to prevent the book case from warping upward and being difficult to level.

What Cause Board Book Warping And Deforming?

Board book warping and deforming is a common technical problem encountered by board book printers.

Board books include hardcover books with gray boards as bookcases and books mounted with cardboard with a weight of 200-250 grams per square meter. They are very common in book printing companies and are prone to quality problems such as warping and deforming.

What cause board book warping and deforming?

1. Raw materials

The structure of the gray board or cardboard itself determines that it is easier to warp and deform during board book printing. Gray board or cardboard has high density and long fibers, and its water absorption has a great influence on the structure of board books.

When absorbing water, the fibers of the gray board or cardboard will stretch, due to gray board or cardboard has a certain thickness, the amount of water absorbed on both sides will be inconsistent, resulting in different elongation lengths of the fibers of the gray board or cardboard, which makes gray board or cardboard deforming.

At the same time, when water is lost, the fibers of the gray board or cardboard will shrink, but the inconsistent water loss on both sides will cause the fibers to shrink inconsistently, resulting in deformation.

Although the gray board or cardboard will deform due to water absorption and water loss, the deformation caused by water loss is more serious than water absorption. In addition, different brands and types of gray board or cardboard have different water absorption and deformation extent in custom board book printing.

2. Ambient temperature and humidity

The environmental temperature and humidity have a great influence on the printing board books. When the ambient temperature and humidity are lower than the water content of the cardboard, it will cause the cardboard to lose water, and the degree of water loss in each part of the cardboard is generally different, resulting in warping and deformation of the cardboard.

When the ambient temperature and humidity are higher than the water content of the cardboard, it will cause the cardboard to absorb water, which will also cause the cardboard to warp and deform.

The degree of deformation in these two cases are different. The deformation when water is lost is much greater than that when water is absorbed, so the warping deformation of board books always occurs in the dry seasons of autumn and winter.

3. Production process

When print a board book, it is necessary to cover or mount with white latex. The white latex contains a lot of water. When the shell is placed or mounted, a large amount of water will enter in the cardboard, but the water does not enter uniformly, which leads to inconsistent moisture content in each part of the cardboard, finally leads to the board books warping and deforming.

4. Production method

When custom board book, some companies use machines to automatically load them, and some companies are artificial shell. Automatic shelling by machines is generally more uniform than the adhesive applied by artificial shell, so that the moisture content of the cardboard is more uniform.

At the same time, the viscosity of the adhesive used for automatic shelling by machine is different from that of the adhesive used for manual shelling, that is, the solid content of the adhesive is different. The solid content of the adhesive should be high, and the water content should be small, and it is less likely to cause board book warping and deforming.

5. Process design

Whether it is gray board or cardboard, all have textures, so when the board book is shelled or mounted, it needs to be carried out according to the texture. A lot of production experience tells us that for custom board bookscustom board books, it is necessary to cover the casing along the grain; for the mounted book, it needs to be mounted along the grain. If it does not follow the grain, the finished cardboard book will have serious warping deformation in the later stage.

In short,raw materials,ambient temperature and humidity, production process, production method ,process design,these five aspects,which are the mainly factors to cause the board book warping and deforming.In next article,we will focus on how to solve board book warping and deforming.