JPS592833B2 - How to dry can material for adhesive cans - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention provides a method for applying a water-soluble synthetic resin adhesive to can materials, for example, the periphery of a can body plate and the periphery of an end plate (or sometimes only the periphery of a can body plate). The present invention relates to a method for drying a can material for adhesive cans in order to fix the adhesive applied to the can material in the best condition in the can manufacturing process in which the can material is dried and then manufactured in a conventional manner.

Recently, adhesive mortars have been developed to avoid solder pollution and are already in practical use, but one of the factors in obtaining a high-quality adhesive mortise is the quality of the technology for firmly fixing the adhesive to the can material.

Adhesive open cans were originally developed with the aim of improving can manufacturing technology that uses solder, and were designed to avoid the pollution that occurs with solder cans, and to reduce material and production costs. However, if the strength of the adhesive part is insufficient, it cannot be put to practical use.

However, even if the desired adhesive strength is obtained in the laboratory, it is essential to obtain a homogeneous and strong adhesive strength in mass production, but if the processing after applying the adhesive is insufficient, the adhesive strength may deteriorate. It was found that the airtightness became insufficient or the airtightness deteriorated.

Therefore, after heating at an appropriate temperature in an atmosphere with a gentle temperature gradient, baking at a predetermined high temperature, and then cooling, an adhesive sealing material with good adhesive strength and airtightness was obtained.

That is, when drying a water-soluble adhesive, if the temperature is suddenly raised to a predetermined temperature, the adhesive becomes porous, which may impair airtightness during can manufacturing.

Therefore, the above-mentioned drawbacks were corrected by increasing the drying temperature at a gentle slope.

In addition, since the adhesive needed to adhere tightly to the can material, it was heated to baking temperature, then allowed to cool, and then forced to cool to harden the adhesive, making it easier to handle the can material during can manufacturing. It is something.

That is, this invention will be explained with reference to embodiments.

The can material is chemically treated steel plate for can manufacturing (thickness 0.32
#1n) to a thickness of 0.1 around the four circumferences of the steel can body material.
A water-soluble synthetic resin adhesive (Nippon Paint Co., Ltd., Zyklon U) was applied to a width of 5 to 9 nm, and the center of the can body was heated over an open fire to make the adhesive lose its fluidity. Start drying this invention.

First, when they are fed from the entrance of the dryer 10 as shown by arrow 2, they are held in parallel by the drying conveyor 3.

The drying conveyor 3 consists of a chain 4 for moving the conveyor and a supporting frame 6 for holding the can body plates 5. Since the carrying frame 6 projects parallel to the chain, one can body plate is attached to each carrying frame. If inserted, the same number of can body plates as the carrier frames will be held on the forward path side (upper side) of the drying conveyor 3.

In this way, the can body board that has entered the dryer is first heated at a uniform gradient from about 35°C to about 65°C in 30 seconds, and then
Raise the temperature to 100℃ in minutes and 30 seconds, and keep at this temperature for 1 minute and 2
After 5 seconds, the temperature was raised to 160℃ for 2 minutes and 5 seconds, and after 3 minutes at this temperature, it was removed from the dryer and dried for 1 minute and 3 seconds.
Allow to cool naturally to 35°C in 0 seconds.

Next, cooling air (for example, 5° C. cold air) is blown out from the cooler 7, and after lowering the temperature to about 10° C. in about 3 minutes, it is sent to the next step.

In the figure, 8 is a coro chute, 9 is a magnetic conveyor, and 10
11 is a timing chain conveyor, 11 is a magnetic chain conveyor, and 12 is a stacker.

In the above examples, the drying temperature was raised to 100°C at a relatively gentle gradient, then held at this temperature, and then further raised to the baking temperature, and baked at a constant temperature at the baking temperature, so the adhesive did not generate bubbles. It is completely dried and then tightly baked and fixed to the can body plate.

This baking prevents the adhesive from peeling off even if an unexpected external force is applied to the adhesive during handling of the can body plate. By then allowing it to cool and then forcing cooling, the adhesive itself becomes considerably hard and hard. Even if something else touches the surface, it will deform against your will and will no longer adhere to other objects.

That is, when drying according to the method of the present invention, not only the strength of fixing the can material and the adhesive increases, but also considerable strength is given to the adhesive to prevent damage caused by contact with other objects, and it is useful in the can manufacturing process. It has various effects such as facilitating handling, homogenizing the adhesive, and improving reliability of airtightness.

In addition, if the adhesive is forced to cool down to about 10℃, there is no risk of blocking even if the can body boards are stacked due to surface hardening.Therefore, there is no risk of the adhesive peeling off or being damaged when taking out the can body boards one by one during use. There is no.

According to the results of the experiment, 100 can bodies that had been left to cool naturally to 35°C were immediately stacked together, left in a room at 20°C for 10 hours, and then taken out one by one, two of which had damaged adhesive.
There were 0 pieces.

On the other hand, 100 can body plates that had been naturally cooled to 35°C and then forcedly cooled to 10°C were immediately stacked and placed in a room at 20°C.
When one sheet was taken out after being left for 0 hours, there was no damage to the adhesive.

[Brief explanation of the drawing]

FIG. 1 is a front view of the apparatus for implementing the present invention, FIG. 2 is a front view of the cooling device, and FIG. 3 is a graph of the temperature in the dryer over one hour. 1...Dryer, 2...Arrow, 3...
...Drying conveyor, 4...Chain, 5...
...Can body plate, 6...Carrying frame, 7...
・Cooler, 8... Coroshoot, 9...
・Magnet conveyor, 10... Timing chain conveyor, 11... Macnet chain conveyor, 12... Stacker.

Claims (1)

[Claims] 1. Slowly move the can material coated with water-soluble synthetic resin adhesive in an atmosphere where the temperature rises with a gentle temperature gradient, and when the ambient temperature reaches around 100℃, slowly move the can material in the atmosphere at this temperature. The film is moved to dry at a constant temperature for a predetermined time, then passed through an atmosphere where the ambient temperature is slowly raised to a fixing temperature of about 160°C, and when it reaches 160°C, it is slowly moved in this temperature atmosphere for a predetermined time. A method for drying a can material for an adhesive can, which comprises drying the can material for an adhesive can, taking it out from the dryer, allowing it to cool naturally to around 35°C, and then forcingly cooling it to around 10°C.