◆ First, the material of the book case
Cardboard is one of the main materials for making hardcover books and thread-bound books. Paper with a basis weight of 225 g/m2 is called paperboard.
Usually, the basis weight and thickness of paperboard are expressed by numbers. For each 1 number, the basis weight of paperboard is increased by 55g/m2. The greater the quantity, the less the number of each cardboard. The commonly used boards in book binding include cover board, envelope board, straw board, white board and so on.
1. Cover plate. Cover board is a kind of cover board for making hardcover books, picture books and so on. It is a high-grade cardboard made of ground wood pulp, semi-chemical wood pulp and waste paper pulp. The color of cardboard is natural fiber. After calendering, the surface is smooth, not starched and tight, and it is not easy to warp. It is an ideal material for making high-grade hardcover book covers.
The cover plate is flat, the plate size is 1350mm×920mm, and the cover plate has three thicknesses: 1.0mm, 1.5mm and 2.0mm. The main technical indexes are defined as follows according to QB355-73: the air tightness is not more than 0.9g/cm3；; ; Tensile strength (longitudinal and transverse uniformity value is not less than)140kgf/cm2; The water content is about 10%. The weight of each piece of cardboard does not exceed 250kg.
2. envelope board. Envelope cardboard is used to make envelopes for hardcover books and photo albums. Cardboard is original pulp color, and it is not sized. After calendering, the paperboard is smooth without warping and has high folding resistance. The envelope board is flat. Cardboard size,
The thin type is 1 150mm×880mm, and the thick type is 1350mm×920mm. Paperboard has five thicknesses: 0.7mm, 1.0mm, 1.5mm, 2.0mm and 2.5mm, which are defined according to QB 13 16-9 1. Its main technical indicators are: compactness and A-shape.
0.75g/cm3; ; Type B is not less than 0.70g/cm3. Folding endurance (vertical and horizontal uniform value) is not less than 20 times, and the water content is about 10%. The tensile strength (longitudinal and transverse uniform values) shall be not less than 0.7mm, 1.0mm, 1.5mm, 2.0mm and 2.5mm respectively according to its thickness, and the type A shall be 14, 20, 29, 39 and 49 kn/m2; Type B is 1 1,16,24,31,34kn/m2. The weight of each piece of cardboard does not exceed 250kg.
3. Straw cardboard. Straw board, also called horse manure board, is an early binding board adopted in China. Its surface is rough and yellow, and it is made of straw fiber as the main raw material. Generally, the sizes of straw paperboard are 787mm×660mm, 787mm× 1092mm, 787mm×546mm, etc. , and flat packaging, divided into symbols, 1, No.2. The thickness of straw cardboard is generally 0.7 mm.
It is cheap to make a book case with straw cardboard. However, cardboard has low compactness, short fiber, strong water absorption, poor toughness and easy folding and warping. When making a book case, stick it with vertical and horizontal cardboard, or heat and pressurize it before use, so that its surface is smooth and tight, and the humidity is appropriate, which can prevent warping and folding after wrapping. Choosing a suitable covering material can enhance its toughness.
☆4. Single-sided white cardboard. The surface of single-sided white cardboard is white, smooth and flat, and the bottom is gray and rough. Strong water absorption, soft texture, thin, stiff and folding-resistant, suitable for single-sided color printing and making packaging boxes. Book binding is mostly used to make medium-sized paper with book cover, soft book cover, loose sleeve and hard lining and hardcover circular endorsement shell.
Single-sided white cardboard is plain paper, which is divided into three types: 1 No.2 and No.3. The size of the cardboard is 787mm× 1092mm.
◆ Second, the cover fabric
There are many kinds of fabrics used to make paperback and hardcover covers, which can be roughly divided into paper fabrics, coated fabrics, fabric fabrics and
Say "no"
Fabric and so on.
1. Paper fabric. Paper cover is the most widely used book cover in China. The cover of paperback and saddle stitch is connected with hardcover.
The cover material of the shell is paper fabric, and the commonly used paper fabrics include book cover paper, white cardboard, patterned paper and offset paper.
(1) book cover paper. Book cover paper, commonly known as cover paper, is a kind of printing paper for making paperback books, magazines and book covers.
Uses are divided into three categories: a, b and C.
The cover paper is flat paper, and the paper sizes are 880mm× 1230mm and 780mm× 1092mm. There are also paper rolls and various colors and embossed patterns.
Book cover paper.
According to the definition of QB 1454-92, the basis weight of cover paper can be divided into three types: 80g/m2, 100g/m2 and 120g/m2.
(2) white cardboard. White cardboard is a kind of paper with high basis weight and thickness, which can be used for printing handprints and making book covers, and can also be used as
clothbound
Paper for the back of a book.
White cardboard is flat paper with a paper size of 787mm× 1092mm. White cardboard is divided into three types: special size, 1 and No.2, with a quantitative of 200g/
M2, 220g/m2, 250g/m2, 260g/m2 and 300g/m2. According to the definition of QB2 12-80, the main technical indexes of white cardboard
(3) patterned paper. Patterned paper is a kind of paper based on thick paper, impregnated with color or embossed with paint on one side. figure
General color, crisp paper, many varieties of colors, good adhesion and bronzing machine performance. Patterned paper can be used as cover material for paperback and hardcover, and can also be used as ring lining, hand thorn, greeting card, etc. It is a suitable and popular cover material at present.
(4) Offset paper. Offset paper is a common cover material for paperback and horse-riding binding (sometimes the same as coated paper), and it is also the main material for hardcover book cover paper. Offset paper has good adhesion. According to the thickness of books and periodicals, the basis weight of cover paper is 40 ~ 200 g/m2.
(5) The cover material of the thread-bound book. The paper used for the cover of thread-bound books is usually the same color as the book block, or blue-green dyed paper. Use silk paper more exquisitely. Base cloth, lacquer paper, PVC cover paper, etc.
(6) Composite processing paper. Composite processing paper is paper composed of two or more identical or different substrates.
Composite processing paper, used as book binding fabric, is mainly a cover material made by properly sticking a dry layer and laminating a PVC film on the paper base (printed matter). The surface of composite processing paper is wear-resistant, glossy, moisture-proof and not easy to get dirty, which plays the role of protecting the book cover and beautifying the book. This material is often used as the cover material of primary school textbooks and general paperback and hardcover books.
2. Coated fabric. In order to improve the surface function, strength, oil resistance, water resistance and dirt resistance of cover materials, various materials are coated on the surface of paper or cloth to obtain a coated cover material with good function and beautiful appearance. Commonly used coated fabrics are varnished cloth, exposed cloth, varnished paper and PVC cover paper.
(1) Lacquer cloth. Lacquer cloth is often used as the fabric of the whole book case and the cloth waist of the book case. There used to be a lot of fabrics for the cover of bound hardcover books. Lacquer cloth generally consists of base, pigment layer and varnish layer. The base of lacquered cloth is ordinary plain cloth, and the surface of the cloth should be delicate and soft, thin and firm, which is the support of lacquered cloth. The middle pigment layer is composed of nitrolacquer and filler (calcium carbonate, titanium dioxide, etc.). ), plasticizer (castor oil, camphor, etc. ) and pigments coated on the subbase. The function of pigment layer is to display color and fill the bottom layer. The top layer of lacquer cloth is varnish layer, also called protective layer, which is generally colorless nitrocellulose lacquer coating. The role of varnish layer is to protect the colored paint layer and increase the surface luster.
As the fabric of hardcover book case, the surface of lacquer cloth should be smooth and flat, and the nitro paint film should not be sticky. The cover made of lacquer cloth should not stick after being pressed for a long time. Lacquer cloth with patterns should have clear patterns, light resistance and hot stamping resistance, which will not affect the strength and luster of the lacquer cloth.
Lacquer cloth has high strength, certain elasticity, no moisture absorption, random size, no fear of moth-eaten, and easy to process hot stamping. However, lacquered cloth is not resistant to organic solvents, so contact with gasoline and kerosene should be avoided to avoid affecting the color of lacquered cloth.
(2) Exposed cities. Exposed cloth, also known as bare cloth, is a material specially used for binding the cover of hardcover books. Pattern detection cloth is based on cloth, and its surface is coated with colorless and transparent silica gel coating. Therefore, it can reveal the luster of textile thread and raw cloth.
You can use bare cloth to make the fabric of the whole bookcase and the middle waist of the bookcase, and bind famous books and scientific books, which can improve the artistic effect of its binding. Because the bare pattern cloth uses cloth as the bottom layer, its adhesiveness and hot stamping adaptability are similar to those of lacquer cloth.
(3) lacquered paper. Lacquered paper is the base paper with 80g/m2 or more, with a nitrocellulose lacquer layer on the surface, smooth surface and average thickness.
Lacquered paper has poor strength, is not resistant to folding and is easy to tear, so it is only suitable for the cover fabric of book cover, and is rarely used as the binding material of book waist.
(4) vinyl paper. Vinyl resin paper is made by coating molten vinyl chloride polymer on a paper base. It has enough mechanical strength and beautiful appearance, can be folded many times, and is suitable for making book covers. However, it needs to use special ink for printing, which is slow in drying, difficult to hot stamping and limited in application.
(5) PVC cover paper. PVC binding paper is a cover binding material based on 80g/m2 coated paper, coated with PVC resin and embossed. With many colors, high mechanical strength, simple processing, low price, wear resistance and good elasticity, it is a popular binding material.
PVC cover paper has good adhesion function, the front side is PVC coating, and the adhesive used has higher adhesion strength, and the back side is paper-based, which is suitable for all kinds of adhesives. The hot stamping machine of PVC cover paper can work well, and the hot stamping temperature does not exceed 160.
When hot stamping patterned PVC cover paper at 100℃, the pressure and hot stamping temperature should be appropriately increased.
3. Fabric. The fabrics used to make the cover materials of hardcover book cases are cotton cloth, silk and so on.
(1) cotton cloth. The main component of cotton cloth is cotton fiber. According to the different interweaving methods of warp and weft, cotton cloth can be divided into plain cloth (fabric with perpendicular warp and weft), twill cloth (fabric with a certain angle between warp and weft) and velvet (fabric with double warp and weft strands).
Common plain fabrics are market cloth, fine cloth, coarse cloth and poplin. Fine cloth is softer and lighter than city cloth; Poplin warp is thick, weft is thin, warp and weft strength is unbalanced, and it is easy to break at weft; Twill fabrics include twill, khaki, wow, gabardine and so on. The texture of twill cloth is tighter and thicker than plain cloth, and it feels softer than plain cloth. Khaki is hard and lint-free, with high fastness and abrasion resistance. Wow, it's a little loose and soft, and the fastness is not high; Gabardine is better than khaki in compactness, softness, folding endurance, wear resistance and fracture resistance. Common velvet fabrics are velveteen and corduroy. Velvet fabric is smooth, shiny and wear-resistant. Corduroy is thick, soft and beautiful in appearance.
In the printing industry, the most widely used cover materials are various colors of hand-printed fine cloth and poplin cloth, which can be used as cover and envelope materials for thread binding and back loading. After the appearance of lacquer cloth, hardcover cloth was gradually replaced by lacquer market, and cloth was rarely used as book cloth except for special needs.
As a cover fabric for binding, its shrinkage, bonding function and hot stamping machine can all play an important role. The fabrics used in the printing house are all purchased from the market, and the scale of shrinkage is not determined according to the needs of the printing house. Therefore, when water-soluble adhesive is used to bond cloth and cardboard together, the shrinkage rate of cloth with large shrinkage rate after drying is different from that of cardboard, which is easy to warp and affect the binding effect. As a binding cloth, plain muslin should have good adhesion function to ensure the adhesion with cardboard. Cloth is as porous as paper, and it is easy for the water-soluble adhesive used for the cover of nuclear paste cloth to penetrate, so the cloth has good adhesion and is easy to mount. The bronzing machine of muslin can work well, because cotton fabric has certain heat resistance. When the temperature rises to 250℃, cotton fiber will decompose, burn or carbonize. The hot stamping temperature of hot stamping materials such as anodized aluminum is between 1 10 ~ 120c, so short-time hot stamping contact will not damage the cloth.
(2) silk. Silk fabrics are made of silk in various colors, including thin and light silk, thick and smooth satin, tough and thin silk, brocade, spinning, crepe and twill.
Silk and silk fabrics are mostly fine weavers, vivid in color and elegant in texture. It is often used as the fabric of hardcover books, thread-bound books, envelopes, advanced picture books and luxury clothes, which is elegant and gorgeous and has unique artistic effects.
Twill is a kind of thin, soft, smooth and thin silk fabric, which is mainly used as the cover of thread-bound books and books packed in the north. Thread-bound book cover corner, scroll filled with calligraphy and painting as the bottom corner.
Satin is a kind of thick, smooth and dense silk fabric, which is mainly used as the fabric of high-end books, picture books, certificates and so on.
The shrinkage of silk is relatively large, generally 6% ~ 7%. In order not to affect the packaging quality, when silk is used as packaging fabric, it should be coated with dilute starch paste first, then pasted with backing paper, and then dried before it can be used for packaging. Because the main component of silk is protein, it is not resistant to acid and alkali, and acidic substances can make velvet swell; Even weakly alkaline substances can hydrolyze protein, thus damaging silk fibers. Therefore, when silk fabrics are used as book covers, acid-base adhesives cannot be used. Silk fabrics can generally meet the requirements of hot stamping temperature, because the surface temperature of silk fabrics can reach 165℃, and when the hot stamping temperature exceeds 175℃, its strength and luster will change obviously. Silk fabrics are not wear-resistant and light-resistant, and have good hygroscopicity. Poor retention can easily lead to moth-eaten and mildew.
(3) chemical fiber fabrics. Chemical fiber fabric is a fabric made of polymer compounds. Polyester or polyester blended fabrics are usually used as bonding fabrics. This material is superior to cotton, silk, wool and other fiber fabrics in wear resistance, acid resistance, alkalinity and moth resistance, but it has not been widely used in binding production at present because of its poor heat resistance and slightly higher price.
☆4. Nonwoven fabrics.
(1) leather fabric. Leather fabric is only used for binding luxury books, because it is expensive, and it is rarely used as the fabric of hardcover books.
Leather has soft texture, high strength, small shrinkage, good wear resistance, folding resistance and coloring power, and the products are bright and shiny. Leather contains lipids and is not easy to bond, so it needs to use a high viscosity adhesive.
Books using leather fabrics should be anti-extrusion, anti-wear, anti-moth, anti-rat, anti-mildew, anti-aging, can not contact with harmful gases, and avoid humidity and sun exposure.
(2) plastic fabrics. In the binding of books, PVC printed or embossed hard plastic covers have been widely used in addition to coated or covered with plastic cover paper. PVC plastic has excellent water resistance, oil resistance and chemical resistance, but it is not easy to bond with other materials. Therefore, high-frequency welding is often used to make the covers of manuals, diaries and dictionaries, such as loose book covers and plastic book covers.
◆ Third, hot stamping materials
Hot stamping material refers to the material that hot stamps all kinds of pictures and texts on the surface of printed matter or other substrates through templates under the action of temperature and pressure.
In book binding, the hot stamping materials used are electrochemical aluminum foil, color foil and metal foil.
Metal foil is a thin metal sheet made of metal extension or metal powder, including red gold foil, silver foil, copper foil and aluminum foil.
Gold foil binding has a long history in China. Gold foil is soft and not easy to oxidize and lose luster. But gold foil is a precious metal, so it is impossible to use it in large quantities. For some high-grade books with reserved value, gold foil is still used for bronzing.
Color foil, also known as powder foil, consists of polymer sheet base, release layer and pigment layer. Pigment layer is a coating composed of pigment, adhesive, additive and solvent, and it is the main body of color foil. The release layer is composed of wax or resin, and its function is to ensure the adhesion between the color coating and the substrate, and to separate the pigment layer from the substrate during hot stamping. In order to make the color foil firmly hot stamping on the hot stamping material, a layer of adhesive is added to the top layer. Color foil is a popular hot stamping material, but the pigment layer is thin and the imprint is not thick enough.
Electrochemical aluminum foil is a hot stamping material composed of basement membrane (16μm thick polyester membrane), isolation layer, color layer, aluminum plating layer and adhesive layer. Most of them are gold and silver, which can replace metal foil as hot stamping material. Suitable for paper, fabric and plastic. Hot stamping uses materials such as leather, which is the most commonly used material for hot stamping binding.
◆ Fourth, ring lining materials
The paper commonly used as ring lining includes offset paper, coated paper, rice paperboard and so on.
Offset paper is mostly white like ring-lined paper, and the amount of ring-lined paper in different grades of books and periodicals is different. The ration of general books and periodicals is 60 ~ 150g/m2, and that of high-grade books and picture books is 200 ~ 250g/m2. In order to avoid wrinkling when pasting, the line direction of the ring-shaped backing paper should be parallel to the spine of the book.
Coated paper, as a ring-backed paper, is used in high-grade books and periodicals, and its basis weight is generally between100 and 250 g/m2. You can also print decorative patterns related to the book content to increase the decorative effect of books and periodicals.
Rice paperboard is a beige embossed paperboard, which is used in photo albums and hardcover books and has a unique charm. The fiber structure of rice paperboard is general, the thickness is consistent, and both sides of the paper are delicate and soft, and the color is consistent.
Rice paperboard is flat paper, and the paper size is 930mm×645mm and 787mm× 1092mm. The quantities are170g/m2 and 200g/m2. According to the industry standard QB323-80, the main technical indexes of rice paperboard are: the tightness is not more than 0.85g/cm3；; The fracture length (vertical and horizontal unified value) is not less than 2200m；; Transverse folding endurance (reciprocating times) shall not be less than 10 times; Sizing degree is not small
in 1.5mm； ; The ash content is 5.0% ~ 8.0%; The transverse flexibility shall not exceed 2.5%.
◆ Five, back-pasted materials
1 book back cloth
The commonly used book back cloth is gauze. It is a kind of plain cotton fabric with sparse weaving, and it is easy to penetrate through the glue after sizing and becomes stiff. Sticking gauze on the back of the book block can improve the smoothness of the back of the book and the adhesion fastness between books, which is beneficial to the formation of the back of the book. Hardcover books must be bonded to the back cloth. For thick paperback books, glue should also be applied to the back cloth to increase the adhesion or sewing fastness of the back.
2 book base paper
The backing paper is the backing paper attached to the back of the book block to reinforce the back of the book.
For paperback books, when the book block thickness is above 15mm, the backing paper should be attached. The wireless binding production line usually uses offset paper or paperboard with a basis weight of 150 ~ 250g/m2. Before use, roll the paper according to the length of the back of the book.
The rewinding is cut to the required width.
For hardcover books, kraft paper with good strength and flexibility should be used as backing paper and tube paper.
☆3 Sebu
The plug cloth is a cotton belt. There is a raised ridge on one side, which is divided into monochrome and color. Stick it on both ends of the back of the book to increase the adhesion of the book and beautify the book. The width of the plug cloth is generally15 mm.
Four ribbons
Ribbon, also known as bookmark tape, is a kind of ribbon with a width of 5 ~ 8 mm, which has many colors such as red, green and yellow. The ribbon is stuck in the middle of the back of the book, and the growth part is sandwiched in the book block and exposed at the foot.
Six, sewing materials
1 wire
Steel wire is the material for leveling and riding.
Iron wire is a wire drawn from low carbon steel. In order to prevent rust, its surface is plated with a layer of rustless metal zinc and tin. Binding wire is mostly galvanized wire, which is divided into round and flat. In order to meet the binding needs of books and periodicals with different thicknesses, the commonly used binding lines are 2 1 ~ 25, with a diameter of 0.5 mm ~ 0.84 mm See Table 4-2 for the selection of line diameters.
The wire used for binding should be uniform in thickness, smooth and shiny in surface, moderate in hardness and elasticity, so as to meet the requirement that the bent wire will not break when binding.
2 binding line
Binding thread is the binding material for sewing, sewing, three-eye binding and thread binding. Binding thread includes wax thread, silk thread, hemp thread and synthetic fiber thread.
The wax on cotton thread is called wax thread, also called cotton wax shine. It is a common material for sewing hardcover book blocks. There are four specifications of cotton thread, the models are: 42s/4, 42s/6, 60s/4 and 60s/6. (s and the previous number indicate the yarn count, oblique.
The number behind the line indicates the number of shares). When binding, cotton threads with different thicknesses are selected according to the thickness of books and periodicals, the number of folds of book posts and the same paper weight.
Silk thread is soft and smooth, but it is expensive and elastic. It is only used when sewing high-grade thread-bound books and picture books.
Commonly used synthetic fiber yarns include nylon yarns and polyester yarns. Nylon thread has high strength, so thinner thread can be used. After locking the money, the back of the book will not be higher and the line will not be broken. But nylon thread is elastic and it is not easy to lock books. After cutting, it is easy to have uneven incision or bent back of the book.
◆ VII. Adhesive materials
☆ 1 Book Pack Order
Under certain conditions, the substance that can bond unified or different kinds of solid materials together through the interface is called adhesive, which is a kind of bonding material.
The method of connecting the surfaces of two solid materials by adhesive force is called adhesion. In book binding, one of the important ways to connect single pages into books and periodicals is bonding, so bonding material is an important material in book binding production.
In book binding, there are two binding methods: face binding and plane binding. The connection of pages, inserts, forms and book posts, the pasting of linings, covers and hardcover book blocks, and the making of book cases and book covers all belong to plane bonding. Wireless binding and hot-melt line hot binding belong to termination. Plane bonding is overlapping, and the contact area is relatively large, so it is relatively firm. End-to-end bonding relies on the penetration of adhesive into the page, so that the end faces of the paper are bonded to each other. According to the depth of adhesive penetration between papers and the thickness of the film formed, the degree of adhesion is the same.
2 requirements for adhesives
In book binding, the bonded objects are mainly fiber materials (paper, cardboard, cloth, etc. ); If books and periodicals are covered with film, the object to be bonded is the bonding between fiber materials and plastic film layers of this department. Bonding fastness directly affects the binding quality of books and periodicals, which not only depends on the structure and performance of the adhesive and the surface of the adherend, but also has a close relationship with the premise of bonding process operation.
Therefore, the choice of adhesive should not only consider the nature of the surface of the adhered object, but also be selected according to the requirements of binding technology and use.
1. Bonding process requirements of adhesive.
(1) activity. The adhesive used for book binding must have good activity, so that the adhesive solution is covered with micropores on the surface of the adhered object, and can fully and truly contact with the uneven surface of the adhered object when bonding.
(2) Wettability. In order to obtain the ideal bonding effect, the adhesive should be well coated on the surface of the adhered object, and the contact area with the surface of the adhered object should be as large as possible. That is to say, only when the adhesive fully wets the surface of the adhered object, then loses its activity and produces a strong cohesive force, can it produce a good bonding effect, so wetting is the premise of bonding. Only when the surface tension of liquid is less than or equal to the surface tension of solid, it is the premise that liquid is completely wetted on the surface of solid. Therefore, the surface tension of the adhesive should be as small as possible. In this case, the contact angle of the liquid adhesive to the surface of the adhered object is less than 90.d egree., so that the surface of the adhered object can be wetted.
(3) viscosity. In order to obtain good bonding effect, the adhesive must have bonding strength besides being fully wetted on the surface of the bonded object. The adhesive strength is determined by the cohesion of the adhesive itself and the adhesive force between the adhesive and the adhered object. The viscosity of adhesive not only directly affects the wetting and exudation speed of adhesive on the surface of the adhered object, but also is the main factor affecting the bonding strength.
High viscosity adhesive has high solid content, low water content, high cohesion and high adhesive strength. However, the adhesive is less active and difficult to penetrate and ooze, so it is mostly used to bond objects with smaller area, such as adhesive sheets, illustrations, packaging covers and so on.
The adhesive with low viscosity has good activity, which is easy to cover all micropores on the surface of the adhered object and increase the adhesion surface area, but its solid content, cohesion and adhesion strength are small. Most of the coated glue solution is absorbed by the adherend, and the remaining glue material is not enough to form a firm glue film on the surface of the adherend.
In binding production, water-soluble adhesives are mostly used. With the continuous evaporation of water, the viscosity of adhesive is also rising. For hot melt adhesive, the viscosity of the adhesive changes with the change of temperature, which greatly affects the adhesive function. In order to ensure the bonding fastness, the viscosity of the adhesive should be controlled according to the types and functions of the adhered object and adhesive.
(4) The time limit for gluing and curing. Adhesive should have a certain coating time and solidification time. The gluing time limit refers to the time that the adhesive can last without losing its viscosity after being coated on the surface of the adhered object. This duration should be the necessary time to complete a binding job, only in this way can the two bonded objects be firmly bonded in the required position before the adhesive solidifies.
(5) In the process of being pasted on an object, the function of the pasted material shall not be disordered.
2. Requirements for using adhesives.
The aging period of (1) glue should be longer than the service life of the design publication to ensure the normal use of the publication.
(2) In order to prevent the cellulose-containing object from being damaged, discolored or faded, the adhesive should be neutral or weakly acidic.
(3) The adhesive should be colorless and transparent.
(4) The adhesive should have strong cohesive force, and the strength of the adhesive layer should be higher than or equal to the strength of the adhered object.
(5) The adhesive layer should be flexible and elastic to ensure that the adhesive film will not be damaged during the further processing of semi-finished products and the reading, storage and transportation of books.
(6) The adhesive should be odorless, non-toxic, non-moldy, non-moth-eaten, not afraid of mouse bites, non-flammable and cheap.
The above are the same requirements for adhesives. When a detailed process is completed, adhesives with appropriate functions should be selected according to the characteristics of the process. For example: ① Bonding single sheets such as ring linings, inserts and forms. Because of the small bonding area and firm bonding, a high viscosity adhesive is needed. (2) The glue used to bond the back of the book should be able to ensure firm bonding at the crease of the post, so that the adhesive film at the bonding place has certain flexibility and can keep the back of the book arched after the book is opened. Therefore, the adhesive with suitable function should be selected according to the type of printing paper. ③ When binding with wireless glue, the glue should have a proper viscosity. When the viscosity of wave liquid is too high, its activity becomes worse, the function of infiltration and exudation is not good, the glue is not easy to cover the micropores on the bonding surface, and the pages are not firmly bonded; When the viscosity of the adhesive solution is too low, a sufficiently thick adhesive film cannot be obtained during the bonding process. ④ Reinsurance
In the completion sequence of the cover and the book, because the glue brushing and the cover or book shell are not the same process, in order to meet the rhythm of the linked production line and facilitate the correction, the cover material or book shell and the back can slide relatively, and glue with longer curing time and higher viscosity should be used.