AgendaIntroduction to Robond L

Robond L Generation 2 Product RangeKeys to Successful Lamination

Keys to a Successful LaminationStorage of Adhesive Store between 5-25C Water based adhesive should be stored in sealed containers with little to no headspace Keep adhesive above freezing temperature Keep adhesive away from direct sunlight and heat Use adhesive within shelf life

Keys to a Successful LaminationMixing of Robond L Stir Robond L series products gently in the original shipping container before transferring to the application pan. All water-based products have the

tendency to phase separate or stratify duringstorage. Proper mixing is critical in obtaining performance proprieties. Two component need to follow special instruction as mentioned in the related TDS.

Keys to a Successful LaminationMixing of catalyst It is necessary that catalyst be added to Robond L adhesive with agitation. Prior to adding the catalyst, use a mechanical mixer

to stir Robond L product with enough speed until avortex is formed, assuring that the adhesive is drawn from the sides and bottom of the mixing vessel.

Slowly charge the appropriate amount of catalyst atthe edge of the vortex, and continue mixing for 5-10 minutes.

Mixing of Catalyst

Keys to a Successful LaminationRecirculation of adhesive to avoid foam Use a low shear pump to pump adhesive from reservoir to coating pan. Minimise foam generation. Keep return distance as short as possible. Return to the bottom of sump, below fluid level. Keep return as far from intake as possible Keep sump full as possible Cover to minimise evaporation Filter at inlet or return line or both

Application Unit PumpingDiaphragm Peristaltic

Keys to a Successful LaminationFoaming Robond L series do not typically require a supplemental defoamer.

If foaming in the coating pan or recirculationsystem is excessive, a non-silicone containing defoamer may be used such as Entschumer

S417

Keys to a Successful LaminationCylinder choice Use a cylinder which is shallow with wide openings, exposing maximum surface area of the wet adhesive to the web being coated. This will

help produce a smooth continuous coating,resulting in more efficient drying, better appearance and adhesion.

Solvent base cell configurations are typically deepwith narrow openings

Keys to a Successful Lamination Applying 1.8 to 2 g/m2. Mechanical 80 lines per cm; Trunk pyramidal 80 type; 34 microns depth; 12 ml/m2 cell volume gravure cylinder Applying 2.3 to 2.5 g/m2. Mechanical 70 lines per cm; Trunk pyramidal 80 type; 45 microns depth; 16,2 ml/m2 cell volume gravure cylinder Electronically 70 lines per cm; Diamond 130, angle 0, volume 11,7 ml/m2

Keys to a Successful LaminationSmoothing Bar Can be helpful, but not always required Used to aid flow-out of the coated substrate before it is laminated to the second substrate.creating a smooth coating and improving drying and appearance of laminates. This should be located as close to the application nip as mechanically practical for best results. Speed should be 2.5 times the speed of the web, in the opposing direction. Clean smoothing bar each and every time the line stops.

Smoothing Bar

Smoothing BarSmoothing bar should be:

placed as close to the coating unit as possible have variable speed control not touch web when line is stopped

highly polished

Keys to a Successful LaminationSurface energy and film treatment Film must be treated with surface tension greater than 38 dynes / cm.

In-line corona treatment is recommended to ensuretreatment greater than 38 dynes / cm and to provide a clear surface to adhere resulting in optimum bond and appearance.

Keys to a Successful LaminationCoating weight and application solids

It is recommended that Robond L products be applied atthe solids level they are received. Typical application solid is 45%

Dilution can change surface tension of the Robondproduct resulting in poor coating flow and appearance.

Dilution can also increase the chance of foaming

Keys to a Successful LaminationCoating weight and application solids Dry adhesive weight: 2.2 2.5 g/m2 Coat weight above this range may lead to reduced

laminate flexibility and negative appearanceCoat weight above this range may lead to difficulty in drying the adhesive and may require elevated nip temperature.

Keys to a Successful LaminationDrying of adhesive Use maximum airflow / velocity Very Important (typical oven temperatures of 80, 90 degrees C.) When using zoned ovens, use the increasing profile temperature. Higher temperature in the first zone can lead to skinning of the adhesive and prevent further drying of inner layers. Try to eliminate recirculation in the ovens introducing fresh air to maximize its power of drying. Laminations made with poorly dried adhesive will not improve over time. You must thoroughly dry the adhesive prior to lamination.

Keys to a Successful LaminationDrying of adhesive

Indications of inadequate drying of the adhesive mayinclude: Hazy laminate appearance Noticeable odor during long term storage of the laminate Poor anchorage to the primary web

Keys to a Successful LaminationNipping For best bonds and laminate appearance, the heated nip roll must be in contact with the primary (adhesive coated) web. Maximize the temperature while maintaining a curl free lamination. Typical nip temperature in range of 70-80C. Maximize pressure while maintaining a curl free lamination. Poor green bonds can be a result of too low of a nip temperature. An indication of low nip temperature is adhesive failure from the secondary web.

Keys to a Successful LaminationNipping The rubber roll should be 85-90 Shore A hardness, free of damage, dried adhesive, tape etc. If using higher temperature on the nip is problematic, it may be possible to increase heat exposure through increased wrap on the nip or increase oven temperature and warm rewind. Does not require chilled roll

Nipping process

Keys to a Successful LaminationWhat to do when line stops:

Leave the cylinder idle. Keep the cylinder wet. DO NOT let cylinder stop running. Doctor blade MUST be raised immediately. Adhesive can potentially dry in the cell of the cylinder causing low coat weight if cylinder stops and doctor blade is not up. If the machine is likely to be stopped for longer than 20-30 minutes, drain the adhesive out from the pan and clean the cylinder thoroughly. Use of chilled gravure roll in extremely hot and humid climates may assist adhesive release and prevent clogging.

Keys to a Successful LaminationCleaning Do not let adhesive dry. It is easy to clean it while it is wet. Drain adhesive from the cylinder, pan and reservoir. Dispose of waste in accordance with local laws. Immediately rinse with water to remove the majority of adhesive residue. Follow by cleaning all wetted part with Ethyl acetate to remove any further residue. Do Not use Ethyl acetate directly to cleanwill gel adhesive Use ethyl acetate to clean dry adhesive.

Keys to a Successful LaminationOff the Laminator The laminate should be clear with good appearance Laminate can be slit quickly following lamination. Initial bond can be measured, but may not be indicative of capability to slit. Robond L series products have very high shear strength. Slitting capability after lamination should be evaluated for each construction. Robond L water based acrylic products exhibit some cold flow, as a result you may see improvement in appearance and bond performance within 24 hours Heat seal, product and thermal resistance can be made after 3-4 days, depending on construction