9950 2 Components Polyurethane Laminating Adhesive （For 121 Celsius Retorting Lamination)

PU-9950 is dual components polyurethane adhesive,which is used for laminating of PET,PA,CPP plastic film for food package. The package is good for hard content,which can be boiled at 121 celsius for 30 minutes.

Properties:

1.This model is with high initial bonding strength,anti boiling.The peeling strength will not decrease heavily after boiling.

2.Suitable for bacteria free package,which needs boiling at  121celsius for 30 minutes.

3.Plastic/plastic laminated package is with good transparency,anti-medium,machinery process property.

Safety:

SGS test ：this product is not contain plasticizer.

Usage Guidelines:

1.         Standard mix ratio: main agent: hardener=20:4. if the air humidity is high（above 80%）, please add more hardener.

2.         Dilution：At first, weigh out the ethyl acetate according to working concentration.（in ethyl acetate, water content cannot exceed 500ppm，alcohol 、amine are not allowed），Then put the ethyl acetate into main agent, then stir steadily and fully.   Then input hardener and stir fully again. It is better to mix drum by drum to make sure mix ratio accuracy. When counting working concentration, solution viscosity should be considered, because viscosity could effect coating situation.

3.       The working concentration and viscosity as below(25℃,3^#Chane cup):

1. Coating Amount：

Here is formula from experience for bumian coating roller and laser coating roller：

Dry base coating amount (g/m²) = 0.2 × working concentration% × hole deepness μ ×density

Electric carving roller and pyramid type embossing roller are not suitable for the formula.  When working concentration is 41%, the density is 1; when working concentration is 26%, the density is 0.96. If accuracy is not required strictly, the density can be ignored.

5. Coating amount (dry base) can’t be lower than 4g/ m².  It can be lower for anti medium package. Coating amount should be constant. The adhesive glue heat endure ability is depending on drying situation, so drying should be assured. Base material surface treat is also very important to peeling strength, esp. for PET、PA and AL.

6. Drying：

To make sure solvent remains figure, drying efficiency is very important. Drying efficiency is depend on hot wind temperature、wind speed and wind volume. 

Higher speed lamination requires higher drying efficiency. On the contrary, when drying efficiency is low, laminating speed should be lowered. Hot wind temperature should be increased by three steps for complete evaporation. For example, if wind speed is 30m/s, laminating speed is 80m, the wind temperature could be set 50-60℃、60-70℃、70-80℃ three sections.

7.  Pressure：It is recommended to raise the pressure and temperature as possible, but do it without damaging the film. The laminating rollers temperature shall be choose from 50-80℃ . Note：Cylinder temperature not means hot roller’s temperature, the temperature at the edge of hot roller not means the temperature at roller-film contact point. The laminating roller press also effects lamination strength. The press is depend on cylinder diameter、air pressure、silicon roller’s hardness and length. What can be often adjusted is air pressure. The hot roller pressure can not be read from pressure meter on lamination machine.

8. Curing：The laminated films should be sent to curing room as soon as possible. At 45-55℃, the unhardened glue will melt and flow flat, which removes bubble and white dot. 24 hours curing can make good bonding strength. Should higher bonding strength required, the curing time could be extended. The air circulation in curing room should be good to make sure the temperature is at same level. Constantly replacing high solvent content air can decrease solvent remains.

Notification:

1. Composite base material must be surface treated. For BOPET、BOPA、CPP. For boiling level CPP, the surface tension should be above 39 dyne.  For BOPET、BOPA, the surface tension should be above 52 dyne.

2. The adhesive glue is better be used within a day. If there is too much rest, it can be diluted with solvent and keep in dry dark place closed, taken as solvent to put in new glue by times when next day working. If there is unclearness or excessive viscosity, it can not be used.