JPS6028541Y2 - Wedge-shaped dam for solvent-free laminator - Google Patents

Description

[Detailed description of the invention] The present invention relates to a wedge-shaped dam in a solvent-free laminator that manufactures laminated webs made of plastic film, paper, aluminum foil, etc. using a one-component or two-component solvent-free adhesive. To enable continuous and good coating of an adhesive with a short pot life for a long time.

2. To produce a good laminated web by preventing gelation and thickening of the adhesive on the coater roll when an adhesive with a short pot life, especially a two-component desorbing agent, is operated continuously for a long time.

, 3. To prevent the adhesive staying on the coater roll, especially in the adhesive bank between the No. 1 roll and the No. 2 roll, from increasing locally by causing the adhesive to flow in the width direction of the roll. .

The purpose is to

FIG. 1 shows a coating laminate part of a solvent-free laminator using a two-component adhesive.

The coating section 8 has four coach-in rolls: No. 1 roll 1, No. 2 roll 2, No. 3 roll 3, No. 4 roll 4,
Wedge dam 10, mixer 11, supply hose 12.12
', pump 13.13', tank 14.14' adhesive supply.

The adhesive supplied between the first roll 1 and the second roll 2 via a tank, a pump, a supply hose, a mixer, and a wedge dam is made into a thin film by a coating roll and applied to the first web 5.

The first web 5 is connected to the second web 6 and the laminated part 9
are laminated to form a laminate web 7.

FIG. 2 illustrates the state of the adhesive bank formed between the No. 1 roll 1 and the No. 2 roll 2.

The adhesive passes through the nip between the first roll 1 and the second roll 2 to form an adhesive 15 based on the film splint principle.

The flow in the bank is pulled by the rolls and flows like a bank flow 16 as shown in FIG. 2, but there is almost no lateral flow in the width direction of the rolls.

Since the flow within the bank is in a state where there is no lateral flow as shown in FIG. 2, problems occur when using a one-component or two-component adhesive with a short pot life.

Figure 3 shows the state in the roll width direction.
The No. 3 roll 3 is shoulder-dropped during coating.

Therefore, the adhesive on the roll inside the coating interior 18 of the coating interior B is successively applied to the web and replaced with new adhesive.

However, the adhesive on the inner and outer coating rolls 17 is i,
Because it is a high clay of ooo ~ 100,000 cps and the lateral flow within the bank is extremely weak, it is rarely replaced.

For this reason, when an adhesive with a short pot life is continuously coated, the adhesive on the roll outside the coating width 17 gradually thickens and becomes a gel, and if coating is continued further, it hardens.

The above-mentioned thickening, gelation, and hardening that occur outside the coating width 17 cause variations in the amount of coating and the appearance of spots on the coated surface, resulting in poor appearance.

If it hardens further, it will cause serious problems such as damaging the roll.

For this reason, with conventional methods, adhesives with a short pot life cannot be coated continuously, or the coating must be stopped after a very short period of time.
The rolls had to be cleaned and restarted.

The present invention was discovered as a result of careful observation of the flow of adhesive on a coating roll as shown in FIGS. 2 and 3, and examples thereof will be described below.

4 and 5, the wedge-shaped dam 10 connected to the mixer 11 is placed close to the outer periphery of the first roll 1 and the second roll 2, and is arranged to minimize the adhesive bank, A groove 2 is formed in the dam surface 19 of the wedge-shaped dam 10.
0 is formed.

The groove 20 is arranged so as to cause a groove flow 22 toward the center where the adhesive outlet 21 is located, as shown in FIG.

Although the cross-sectional shape of the groove is not specified, it is preferable that the cross-sectional area of the groove decreases as it moves away from the apex of the wedge-shaped dam 10 and slopes toward the center in the width direction, as shown in FIGS. 4 and 5. .

In the embodiments shown in FIGS. 4 and 5, the dam surface 1 on the 1st roll 1 side
Although the groove 20 is provided in the groove 9, the groove 20 may be provided in both the dam surfaces on the second roll 2 side.

In any case, the feature of the configuration of the present invention is that the adhesive flow in contact with the dam surface is introduced into the groove 20 to provide a lateral flow component.

The grooves 20 disposed on the dam surface 19 give a lateral flow component to the flow of adhesive in contact with the dam surface 19, and since the dam 10 and the No. 1 roll 1 are disposed close to each other,
The flow 22 in the groove is accelerated as it moves away from the dam apex, forcing a lateral flow.

As a result, when viewed from the cross-sectional direction of the roll in FIG. 4, the grooves 20 force a flow that spirals toward the center in the width direction of the roll, and at the same time, as shown in FIG. A reverse flow 23 occurs.

This flow 22 in the groove and the accompanying reverse flow 23 can replace the adhesive on the outside 17 of the coating width and the inside 18 of the coating width in FIG. 3.

In addition, conventionally, the residence time outside the coating width was limited, but according to the present invention, the adhesive is replaced between the outside and inside of the coating width, so the residence time can be relatively reduced. .

According to the present invention as described above, (1) Since the adhesive on the outside of the coating width and the adhesive inside the coating width are replaced, even if an adhesive with a short pot life is used, there is no increase in viscosity,
No gelation occurs.

As a result, it is possible to prevent variations in the coating amount and poor appearance of the laminate web due to gel transfer to the coated surface.

(2) Adhesives with short pot lives can be applied continuously for long periods of time.

(3) Furthermore, when using a two-component adhesive, the degree of mixing of the two components increases due to the lateral flow within the bank, so that the quality of the laminated web, such as the adhesive strength, is improved and stabilized.

(4) The transverse flow within the bank speeds up the replacement of the adhesive, resulting in a shorter average residence time within the bank.

Although the pot life is short, it is possible to apply a higher performance adhesive.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the coating/laminate part of a solvent-free laminator using a two-component adhesive. Figure 2 shows the adhesive bank formed between roll 1 and roll 2. Figure 3 shows the upper part of the coating roll according to the present invention.
Wedge-shaped dam between No. 1 roll and No. 2 roll. FIG. 5 is a view taken along arrow A in FIG. In the diagram: - 1... Roll 1, 2... Roll 2, 3... Roll 3, 4... Roll 4, 5... ...First web, 6...Second
Web, 7... Laminate web, 8...
・Coating part, 9... Laminating part, 10
... Wedge-shaped dam, 11 ... Mixer, 12.12' ... Supply hose, 13.13'
...Pump, 14,14'...Tank, 15...Adhesive layer, 16...Bank flow, 17...Coating Width outside, 18...
Coating width inside, 19...Dam surface, 20...
・Groove, 21...Adhesive outlet, 22...
Flow in the groove, 23... Reverse flow.

Claims (1)

[Scope of utility model registration request] In a roll coating machine composed of multiple rolls,
A wedge-shaped dam for a solvent-free laminator, characterized in that it is disposed close to a pair of roll parts forming an adhesive supply part, and has an oblique groove formed on the surface that contacts the adhesive.