JPH0694168B2 - Laminating method - Google Patents

Description

The present invention relates to a method for laminating a film-like soft packaging material, and more particularly to a laminating method for practically shortening curing time for curing.

[Conventional technology]

Conventionally, a so-called polyol / polyisocyanate type adhesive such as polyurethane / polyurethane isocyanate and polyester / polyisocyanate has been used as a laminating method for soft packaging materials, and after laminating
After being placed in a 40 ° C. curing room and cured for 2 to 5 days to complete the curing reaction, it was transferred to post-processing steps such as slitter and bag making.

[Problems to be solved by the invention]

As a result of diligent research, the inventors of the present invention found that a large amount of moisture was involved in the reaction of these polyols / polyisocyanates, and initially examined humidification during curing. Since it is supplied at a temperature of 1000 to 4000 m and it takes a long time for moisture to penetrate during curing, the curing time is not sufficiently shortened except for the outermost wound portion of the web, but the film is laminated. The present invention has been completed by finding that if the surface or the adhesive-coated surface is humidified, the curing time can be substantially shortened uniformly.

The reason why the curing reaction is accelerated by moisture is not always clear, but the reaction between water and excess polyisocyanate and the accelerating effect of its reaction product, polyurethane polyurea, contribute synergistically. It is considered to be a thing.

[Means for solving problems]

The film used in the present invention is not particularly limited, and a film usually used for soft packaging can be used. An example is given below.

To apply a polymer coating such as vinylidene chloride to these films in advance, or to print with printing ink,
Although not necessary, it is often effective in terms of appearance and other aspects.

The polyol / polyisocyanate adhesive used in the present invention is not particularly limited as long as it does not substantially contain water. Any adhesive may be used as long as it has a mechanism of curing by the reaction between the hydroxyl group of the polyol and the isocyanate group of the polyisocyanate. Typical polyols include phthalic acid-based polyester polyols, polyalkylene ether-based polyurethane polyols, polyester-based polyurethane polyols, and the like. Polyisocyanates include diisocyanate dimers, trimers, and trimethylolpropane. Examples thereof include adducts of glycerin and the like with polyfunctional hydroxy compounds, so-called isocyanate adducts, polyether urethane isocyanates and the like.

Further, the forced humidification may be performed by spraying water vapor or mist-like water from the humidifying device onto the film surface or the adhesive coated surface to humidify, and the curing time can be extremely shortened by sticking after spraying.

〔Example〕

 Examples of the present invention will be described below.

Example 1 Seika Bond E-263 (a solid component of 63% was obtained by using an ethyl acetate solution of a phthalic acid type polyester polyol manufactured by Dainichiseika Co.
%) 100 parts by weight (main ingredient) and Seika Bond C-26
(A solution of trimethylolpropane / TDI adduct manufactured by Dainichiseika Kogyo Co., Ltd. in ethyl acetate, containing 40% solid content) 20
A mixed solution of 100 parts by weight of ethyl acetate (part by weight) (hardening agent) is used as an adhesive, and a gravure coating type dry laminator is used as a laminating condition.
The drying temperature setting is 60 ℃ in the first zone, 70 ℃ in the second zone,
The third zone is 80 ℃, the processing speed is 120m / min, the Niprol temperature is 50 ℃, and PET (Lumirror Toray Co., Ltd.) and CPP (Trefuan No.3701 Toray Co.) are used as the base film.
Laminate T (12μ) / CPP (60μ).

Under the above laminating conditions, apply the adhesive to the PET side, and after drying, spray mist-like water from the humidifier (using two corona ultrasonic humidifiers UF-450S) on the adhesive coated surface for 1 hour. Pasted together

Example 2 100 parts by weight of Seikabond A-158W (70% solid content in a solution of polyalkylene ether urethane polyol manufactured by Dainichiseika Kogyo Co., Ltd. in ethyl acetate) and Seikabond C-90 (polyalkylene manufactured by Dainichiseika Kogyo Co., Ltd.) Kiss reverse roll coating is used as a laminating condition by using a mixed solution of 100 parts by weight of ether urethane polyisocyanate in ethyl acetate (solid content: 80%) and 400 parts by weight of ethyl acetate (solid content: 25%) as an adhesive. Using a dry laminator, set the drying temperature to 60 ℃ in the first zone, 70 ℃ in the second zone and 80 in the third zone.
℃, processing speed 130m / min, Niprol temperature 45 ℃, as base film OPP (FOR Nimura Chemical Co., Ltd.), CPP (FHK2
NIPPON CHEMICAL INDUSTRIES, LTD., OPP (25μ) / CPP (40
μ) is laminated.

An adhesive was applied to the OPP side under the above-mentioned laminating conditions, and after drying, water vapor from a humidifying device was sprayed onto the adhesive-coated surface for bonding.

Example 3 Seika Bond E-320 (60% solid content in ethyl acetate solution of phthalic acid polyester polyol manufactured by Dainichiseika Co., Ltd.)
100 parts by weight of Seika Bond C-75N (75% solid content of trimethylolpropane / HMDI adduct manufactured by Dainichiseika Kogyo Co., Ltd. in ethyl acetate 75%) and 110 parts of ethyl acetate mixed solution (solid content 30.7%) It is used as an adhesive, and a gravure coating type dry laminator is used as a laminating condition.
Laminate PET (12μ) / Al foil (9μ) / CPP (60μ) as the base material film at ℃, processing speed 100m / min, Niprol temperature 55 ° C.

Under the above-mentioned laminating conditions, the PET side and the aluminum foil side were coated with an adhesive, and after drying, water vapor from a humidifying device was sprayed onto the coated surface of the adhesive for bonding.

Comparative Example 1 A laminate in which the adhesive used and the laminating conditions of Example 1 were the same and were not humidified.

Comparative Example 2 A laminate in which the adhesive used and the laminating conditions of Example 2 were the same and were not humidified.

Comparative Example 3 A laminate in which the adhesive used and the laminating conditions in Example 3 were the same and were not humidified.

The following table shows the results obtained by measuring the curing rates of the above-mentioned examples and comparative examples. (However, regarding the method for determining the curing rate, the rate of consumption of NCO group absorption (2250 cm ^-1 ) in the infrared region is used to determine that the curing rate is 100%.) [Effects of the Invention] As is clear from the above example, curing in Comparative Example (1)
It took 5 days to reach 100%, but in Example (1) where humidification was performed, it reached 100% in 1.5 days.

In Comparative Example (2), what took 5 days was cured in 1 day.
It was 100%. In Comparative Example (3), what took 7 days became 100% in 2 days.

As described above, the present invention has the effect of shortening the curing time by performing forced humidification.

Claims (1)

[Claims] 1. When laminating web-shaped films, a polyol polyisocyanate adhesive containing substantially no water is used, and the film surface or the adhesive coated surface is forcibly humidified when laminating. Laminating method