LOCTITE LIOFOL LA 7271

1 part by weight

1 part by volume

• Designed for controlled peel on blister packaging. This system can be used for film/film and film/foil food or pharmaceuticals packaging laminations.
• This adhesive also can be used for food packaging laminations, health care, pharmaceutical and cosmetic applications.

% Running Solids

Determine the adhesive viscosity based on your application method, cylinder selection and desired coating weight. Typically, a coating weight between 0.6 – 1.5 lb/ream (1.0-2.4 gm/m2 ) is used for standard laminations. The chart below may be used for reference and is typical for TYCEL 7966/LOCTITE LIOFOL LA 7271 when diluted with Ethyl Acetate. Determine the % running solids required:

Solvent Selection

Select a dilution solvent. Urethane grade ethyl acetate is recommended. However, methyl ethyl ketone or acetone may also be used. Using a solvent other than ethyl acetate will change the viscosity curve shown above.

Dilution

Calculate the amount of solvent required to dilute the adhesive and curing agent to the desired % running solids.

Adhesive Mixing

• Weigh the desired amount of adhesive into a clean, dry container. While stirring under slow agitation, add the total amount of solvent calculated based on the desired batch size. Stir slowly for approximately 10 minutes.
• Slowly add the curing agent to the stirring adhesive mixture. Stir for an additional 10 – 15 minutes. Cover the container to prevent additional solvent loss

Application Method

• The recommended method of application for this adhesive mix is with a standard gravure roll coater. When using this type of conventional coating equipment, apply the adhesive at 30-45% TSC for best results.
• Depending upon the film or foil combination, and the end use of the lamination, apply approximately 0.6 – 1.5 lbs/ream (1.0-2.4 gm/m² ) coating weight of adhesive.

Drying

• Optimum drying conditions are dependent on the specific machine speed, coating weight, dwell time, and efficiency of the dryer. A system with good air volume and exhaust is more effective than extremely high temperature to remove the solvents.
• The drying conditions should correlate to machine speed:
• Example: 50 – 60^oC (122-140^oF) at 165 fpm 60 – 80^oC (140-176^oF) at 500 fpm
• Dryers with multiple zones should be staged from a lower temperature in the first zone to higher temperatures in successive zones. This will facilitate solvent removal without adhesive skinning.
• Extremely high temperatures and over-drying the adhesive can result in cure irregularities and lower performance. Caution should be taken to establish the optimum process conditions for your equipment.

Combining Nip

• The lamination of the primary and secondary substrates should exhibit excellent initial tack when combined at heated nip temperatures of 122-158°F (50-70°C).
• Pressure and temperature of the laminating nip may require adjustment based on the appearance, degree of wrap angle, dwell time, and thickness of the substrates.

Pot Life

• Typically, this product at 40% solids in a closed container has a working time of 8 - 12 hours without substantial viscosity increase. However, solvent moisture content, relative humidity, temperature, solvent loss, and % running solids can all shorten the pot life of the adhesive mixture.
• Due to the chemical activity of the material, using material that is older than 8-12 hours is not recommended.

Curing

The laminate can be further processed, rewound and slit after 1-2 days of curing at room temperature. High initial bonds due to green tack will drop as the adhesive cures. Final bond strength should be achieved within 14 days of storage at room temperature. Cure rate may depend on film combination.

Equipment Clean Up

Clean up of the application station is accomplished with solvents such as ethyl acetate, methyl ethyl ketone, acetone, or toluene. Protective gloves should be worn.

• These products have a storage life of twelve months from date of manufacture.
• They should be held at normal warehousing temperatures and stored in the original, unopened containers.
• Containers of the adhesive or curing agent should not remain open for an extended period of time.
• Material from opened containers should be consumed within a short period of time.
• It is necessary to use all the adhesive, once the container is opened, unless there is means of purging the container with dry nitrogen.