Starch adhesives are generally used by carton manufacturers because of their superiority over silicate adhesives. Let's talk about how to configure carton adhesives for your reference:
First, the preparation
(I) Carton adhesive preparation materials and their main functions
1. Starch—The main adhesive substance is insoluble in water, and it expands and gelatinizes with the increase of the temperature in the water. When it reacts with the caustic soda solution, it is fully expanded and the viscosity increases.
Technical indicators: acidity, mesh number, spot, whiteness, protein content, water content.
Note: The protein content can not be too high, otherwise it is easy to produce foam and affect the quality of the adhesive.
2. Water - Solvents Increase the fluidity of the adhesive, but pay attention to the water ratio.
3, soda ash - gelatinizer dissolved in water, release a certain amount of heat, the role of its aqueous solution and starch, can reduce the gelatinization temperature, increase the viscosity.
4, borax (Na2B4OT 10H2O) - crosslinker
When the solution is added to the main tank, the free acid (boric acid) is released, and the hydrogen bond binds to the starch adhesive to increase the firmness of the adhesive film and promote the adhesion of the adhesive.
Note: The amount must be controlled properly, too little, easy to penetrate, affect the strength of the box; too much, the adhesive is easy to gel, brittle, adhesive strength is affected.
(b) Carton binder preparation procedure and chemical principle
1, the preparation method In the automatic production line of corrugated board, we generally use the alkaline paste method (two-step method) to prepare starch adhesive, the process flow is as follows:
Preparation procedure:
The first step: Preparation of carrier starch (mature starch).
A. Place metered water in a carrier reaction vessel and heat to 55-60°C.
B. Put a certain amount of starch into the carrier reaction tank and stir while stirring.
C. After stirring evenly, the caustic soda solution with a certain concentration is added to the carrier tank three times, and stirring is continued for a certain period of time to obtain a beige-colored transparent paste, which is obtained by aging the starch (slurry paste).
The second step: the preparation of the main starch
A. Put a certain amount of water in the main reactor and heat to 30-35°C.
B. Put a certain amount of starch into the main reaction tank and stir while stirring.
C. After stirring evenly, dissolve the borax with hot water and add and stir for a certain period of time.
D. The "cured paste" prepared in the carrier is gradually added to the main tank and stirred while being added.
The third step: After the above “slurry paste†is mixed with the raw paste in the main tank, a translucent semi-cured adhesive is prepared, which is used for heat preservation in the storage tank and can be used for the machine table.
note:
(1) Must be fully stirred in the production process, otherwise it is easy to produce rubber block, block the pipe, affect the adhesive effect.
(2) In the carrier tank must be made of "slurry paste", otherwise the initial viscosity of the adhesive will be affected and the adhesion will be affected.
2, the principle of adhesive bonding
The gelatinization process of starch is shown in the figure:
The starch granules are fully stirred under the action of a certain temperature water, and the surrounding moisture is gradually swollen under the catalysis of caustic soda, from several times expansion to tens of times, to the ultimate (gelatinization temperature), and with the increase of temperature, the starch granules It begins to collapse, and gradually disintegrates into small pieces. After soaking into the inner side of the tissue paper and core paper, it begins to adhere and requires a certain initial viscosity (mainly obtained by the action of caustic soda solution and borax solution), and the temperature rises. The moisture content of the starch granules evaporates, and is partially absorbed by the facial paper and the core paper, so that the initial viscosity is rapidly carried out. The adhesive-bonded inner paper, core paper, corrugated cardboard and noodle paper become a whole to achieve the purpose of bonding.
Second, use
(I) Several factors that affect the quality of adhesives
1, viscosity
The viscosity is also the expression of the initial viscosity of the adhesive. The level of the initial viscosity directly affects the adhesive performance of the corrugated cardboard. Therefore, the quality control of the adhesive can be expressed by the “viscosityâ€.
(1) Viscosity and temperature
Temperature (°C) 55 60 65
Viscosity (initial) 50 65 140
The sufficient swelling of the starch granules requires a certain temperature, which is mainly provided by heating and caustic soda solution. Therefore, in order to make the viscosity of the adhesive suitable, it is necessary to pay attention to the control of the water temperature and the addition amount of caustic soda.
(2) Borax and Viscosity
Borax (kg) 1.8 2
Viscosity (seconds) 60 100
The amount of borax is also a factor affecting the viscosity, the actual application must be appropriate, the amount of small, so that the adhesive is too thin and easy to penetrate into the paper, causing corrugated cardboard run, collapse; a large amount of adhesive will become Rubbery loses adhesion.
Adjust the viscosity method:
When the viscosity is high, the starch content in the carrier can be appropriately reduced;
When the viscosity is low, the borax solution can be properly added.
2, aging temperature
The temperature at which the starch binder starts to thicken and shows adhesive properties due to the gradual ripening of raw starch in the binder raw material.
Due to the different quality of starch or starch, the maturation temperature is different. Therefore, in actual operation, the heating temperature needs to be adjusted, and the adjustment of the amount of caustic soda is mainly adopted.
3. Solid content in starch binder
Measuring the solid content in the adhesive is a method of judging the binding ability.
Common formula: g3-g1
Solid content = one hundred and eleven one hundred 100%
G2-g1
g1——Aluminum weigh plate kg
G2 - Wet adhesive plus weigh plate kg
g3——After drying, the adhesive adds weighing plate kg
4, PH value (acid, alkaline)
We know that starch granules contain certain fatty acids and react with caustic soda solution to neutralize weakly alkaline binders. Therefore, the pH of the binder can be determined to know whether the reaction is complete or not. The quality of the mixture.
PH value should generally be between 8-9.
5. Equipment performance and other factors In the process of carton adhesive formulation, the influence of equipment performance, instruments, and meters cannot be ignored.
(b) Use of starch binders
1. Effect of the viscosity of starch adhesive on the speed of the vehicle
After the starch adhesive is prepared, due to the influence of the environment, the viscosity will undergo a certain change, which will inevitably affect the vehicle speed during use.
The speed of the vehicle affects the amount of glue applied and the bonding effect. Therefore, we need to control the speed of the vehicle based on the viscosity of the starch adhesive so as to facilitate the use of the adhesive.
If the speed is too fast, it can easily cause uneven coating, and the amount of glue is insufficient, which affects the effect of adhesion. When the speed is too slow, the adhesive penetrates into the layers of the board and causes a high water content of the box, which directly affects the resistance of the box. Compressive strength and other physical properties.
2. The effect of glue volume control on the bonding quality
During the production process, the replacement of the product, the quality of the raw materials, the speed of the vehicle, and the temperature of the hot plate will affect the use of the adhesive. If the actual amount of glue is not controlled, the effect on the bonding quality is Can imagine.
(1) The same amount of paper, due to the different pulp and filler used in papermaking, causes intrinsic tightness and penetrability. Pulp thick, small tightness of the paper, the general penetration, the amount of glue should not be too large; paper pulp, tightness of the paper, the penetration is poor, the glue should not be too small.
(2) The speed of the vehicle causes changes in the amount of glue to be applied, and there are also certain requirements for the amount of glue applied.
(3) The hot plate temperature also has an effect that can not be ignored on the amount of glue and the speed of the vehicle.
3, speed: the impact of the hot plate temperature on the adhesive effect of the carton adhesive
(1) The adhesive quality is stable and the amount of glue applied is constant. When the vehicle speed is less than 400 rpm, the adhesive effect decreases as the temperature of the hot plate increases. example:
Hot plate average temperature (°C) 111.6 113 125 131
Bonding strength (N/cm2) 6.7 6.65 5.2 4.4
(2) The quality of the adhesive is stable and the amount of glue applied is constant. When the vehicle speed is above 500 rpm, the higher the average temperature of the hot plate, the better the adhesive effect. The following table:
First, the preparation
(I) Carton adhesive preparation materials and their main functions
1. Starch—The main adhesive substance is insoluble in water, and it expands and gelatinizes with the increase of the temperature in the water. When it reacts with the caustic soda solution, it is fully expanded and the viscosity increases.
Technical indicators: acidity, mesh number, spot, whiteness, protein content, water content.
Note: The protein content can not be too high, otherwise it is easy to produce foam and affect the quality of the adhesive.
2. Water - Solvents Increase the fluidity of the adhesive, but pay attention to the water ratio.
3, soda ash - gelatinizer dissolved in water, release a certain amount of heat, the role of its aqueous solution and starch, can reduce the gelatinization temperature, increase the viscosity.
4, borax (Na2B4OT 10H2O) - crosslinker
When the solution is added to the main tank, the free acid (boric acid) is released, and the hydrogen bond binds to the starch adhesive to increase the firmness of the adhesive film and promote the adhesion of the adhesive.
Note: The amount must be controlled properly, too little, easy to penetrate, affect the strength of the box; too much, the adhesive is easy to gel, brittle, adhesive strength is affected.
(b) Carton binder preparation procedure and chemical principle
1, the preparation method In the automatic production line of corrugated board, we generally use the alkaline paste method (two-step method) to prepare starch adhesive, the process flow is as follows:
Preparation procedure:
The first step: Preparation of carrier starch (mature starch).
A. Place metered water in a carrier reaction vessel and heat to 55-60°C.
B. Put a certain amount of starch into the carrier reaction tank and stir while stirring.
C. After stirring evenly, the caustic soda solution with a certain concentration is added to the carrier tank three times, and stirring is continued for a certain period of time to obtain a beige-colored transparent paste, which is obtained by aging the starch (slurry paste).
The second step: the preparation of the main starch
A. Put a certain amount of water in the main reactor and heat to 30-35°C.
B. Put a certain amount of starch into the main reaction tank and stir while stirring.
C. After stirring evenly, dissolve the borax with hot water and add and stir for a certain period of time.
D. The "cured paste" prepared in the carrier is gradually added to the main tank and stirred while being added.
The third step: After the above “slurry paste†is mixed with the raw paste in the main tank, a translucent semi-cured adhesive is prepared, which is used for heat preservation in the storage tank and can be used for the machine table.
note:
(1) Must be fully stirred in the production process, otherwise it is easy to produce rubber block, block the pipe, affect the adhesive effect.
(2) In the carrier tank must be made of "slurry paste", otherwise the initial viscosity of the adhesive will be affected and the adhesion will be affected.
2, the principle of adhesive bonding
The gelatinization process of starch is shown in the figure:
The starch granules are fully stirred under the action of a certain temperature water, and the surrounding moisture is gradually swollen under the catalysis of caustic soda, from several times expansion to tens of times, to the ultimate (gelatinization temperature), and with the increase of temperature, the starch granules It begins to collapse, and gradually disintegrates into small pieces. After soaking into the inner side of the tissue paper and core paper, it begins to adhere and requires a certain initial viscosity (mainly obtained by the action of caustic soda solution and borax solution), and the temperature rises. The moisture content of the starch granules evaporates, and is partially absorbed by the facial paper and the core paper, so that the initial viscosity is rapidly carried out. The adhesive-bonded inner paper, core paper, corrugated cardboard and noodle paper become a whole to achieve the purpose of bonding.
Second, use
(I) Several factors that affect the quality of adhesives
1, viscosity
The viscosity is also the expression of the initial viscosity of the adhesive. The level of the initial viscosity directly affects the adhesive performance of the corrugated cardboard. Therefore, the quality control of the adhesive can be expressed by the “viscosityâ€.
(1) Viscosity and temperature
Temperature (°C) 55 60 65
Viscosity (initial) 50 65 140
The sufficient swelling of the starch granules requires a certain temperature, which is mainly provided by heating and caustic soda solution. Therefore, in order to make the viscosity of the adhesive suitable, it is necessary to pay attention to the control of the water temperature and the addition amount of caustic soda.
(2) Borax and Viscosity
Borax (kg) 1.8 2
Viscosity (seconds) 60 100
The amount of borax is also a factor affecting the viscosity, the actual application must be appropriate, the amount of small, so that the adhesive is too thin and easy to penetrate into the paper, causing corrugated cardboard run, collapse; a large amount of adhesive will become Rubbery loses adhesion.
Adjust the viscosity method:
When the viscosity is high, the starch content in the carrier can be appropriately reduced;
When the viscosity is low, the borax solution can be properly added.
2, aging temperature
The temperature at which the starch binder starts to thicken and shows adhesive properties due to the gradual ripening of raw starch in the binder raw material.
Due to the different quality of starch or starch, the maturation temperature is different. Therefore, in actual operation, the heating temperature needs to be adjusted, and the adjustment of the amount of caustic soda is mainly adopted.
3. Solid content in starch binder
Measuring the solid content in the adhesive is a method of judging the binding ability.
Common formula: g3-g1
Solid content = one hundred and eleven one hundred 100%
G2-g1
g1——Aluminum weigh plate kg
G2 - Wet adhesive plus weigh plate kg
g3——After drying, the adhesive adds weighing plate kg
4, PH value (acid, alkaline)
We know that starch granules contain certain fatty acids and react with caustic soda solution to neutralize weakly alkaline binders. Therefore, the pH of the binder can be determined to know whether the reaction is complete or not. The quality of the mixture.
PH value should generally be between 8-9.
5. Equipment performance and other factors In the process of carton adhesive formulation, the influence of equipment performance, instruments, and meters cannot be ignored.
(b) Use of starch binders
1. Effect of the viscosity of starch adhesive on the speed of the vehicle
After the starch adhesive is prepared, due to the influence of the environment, the viscosity will undergo a certain change, which will inevitably affect the vehicle speed during use.
The speed of the vehicle affects the amount of glue applied and the bonding effect. Therefore, we need to control the speed of the vehicle based on the viscosity of the starch adhesive so as to facilitate the use of the adhesive.
If the speed is too fast, it can easily cause uneven coating, and the amount of glue is insufficient, which affects the effect of adhesion. When the speed is too slow, the adhesive penetrates into the layers of the board and causes a high water content of the box, which directly affects the resistance of the box. Compressive strength and other physical properties.
2. The effect of glue volume control on the bonding quality
During the production process, the replacement of the product, the quality of the raw materials, the speed of the vehicle, and the temperature of the hot plate will affect the use of the adhesive. If the actual amount of glue is not controlled, the effect on the bonding quality is Can imagine.
(1) The same amount of paper, due to the different pulp and filler used in papermaking, causes intrinsic tightness and penetrability. Pulp thick, small tightness of the paper, the general penetration, the amount of glue should not be too large; paper pulp, tightness of the paper, the penetration is poor, the glue should not be too small.
(2) The speed of the vehicle causes changes in the amount of glue to be applied, and there are also certain requirements for the amount of glue applied.
(3) The hot plate temperature also has an effect that can not be ignored on the amount of glue and the speed of the vehicle.
3, speed: the impact of the hot plate temperature on the adhesive effect of the carton adhesive
(1) The adhesive quality is stable and the amount of glue applied is constant. When the vehicle speed is less than 400 rpm, the adhesive effect decreases as the temperature of the hot plate increases. example:
Hot plate average temperature (°C) 111.6 113 125 131
Bonding strength (N/cm2) 6.7 6.65 5.2 4.4
(2) The quality of the adhesive is stable and the amount of glue applied is constant. When the vehicle speed is above 500 rpm, the higher the average temperature of the hot plate, the better the adhesive effect. The following table:
About Our Smart Cabinet
Our smart cabinet is a technologically advanced storage solution that incorporates various features to enhance convenience, organization, and security. It utilizes the Internet of Things (IoT) technology to connect with other devices and provide users with remote access and control.
One of the key features of a smart cabinet is its ability to track and manage inventory. It uses sensors and RFID (Radio-Frequency Identification) technology to monitor the quantity and location of items stored inside. This ensures efficient inventory management, reduces the risk of stockouts, and enables automatic restocking when supplies are running low.
In addition, a smart cabinet often includes a digital interface or display that allows users to easily locate and retrieve items. This can be particularly useful in large storage facilities or healthcare settings where quick access to specific items is crucial.
Security is another important aspect of a smart cabinet. It typically includes biometric authentication, such as fingerprint or facial recognition, to ensure that only authorized individuals can access the contents. Additionally, it may have surveillance cameras or sensors to detect any unauthorized access or tampering.
Furthermore, a smart cabinet can be integrated with other smart devices and systems. For example, it can connect with a hospital's electronic medical records system to automatically update inventory levels when supplies are used. It can also be linked to a mobile app, allowing users to remotely monitor and manage the cabinet's contents.
Overall, a smart cabinet offers a modern and efficient solution for storage and inventory management. By leveraging advanced technologies, it streamlines processes, improves security, and enhances user experience.
Smart Cabinets,Assembled Smart Locker,Digital Electronic Locker,Smart Fingerprint Metal Locker
Henan Toda Technology Co., Ltd. , https://www.httofficefurniture.com