VT-447(B) Prepreg/Laminate

UL Approval: E214381 Version: 12/12/2024 /127/128/130

Storage Condition & Shelf Life

Prepreg Laminate
Storage Condition Temperature < 23℃ (73℉) < 5℃ (41℉) Room
Relative Humidity < 55% RH / /
Shelf Life 3 Months 6 Months 24 Months (airproof)

Precautions In Handling

  • The prepreg exceeding shelf time should be retested.
  • Take care in handling thin core laminates as they are easily damaged.
  • If the prepreg is not consumed within 48hrs after opening the vacuum package, it is recommended that the bags be resealed.
  • Material is available in both long and short grain. The grain direction is indicated on the label with an arrow.

Prepreg Availability

PP Type Resin Content Press Thickness (mil) Dk Df
@ 1GHz @ 5GHz @ 1GHz @ 5GHz
7628 45% 7.6 4.34 4.24 0.012 0.013
2116 54% 4.8 4.07 3.97 0.014 0.015
1080 64% 3.5 3.90 3.76 0.015 0.016

① Press thickness test condition---Prepreg lamination size 18”*24”, Copper Foil---1oz/1oz, Flow---about 5%; ② Make laminated prepreg to micro-section and measure the thickness with microscope; this thickness is used for resistance design calculation. ③ The thickness measured with micrometer is 0.2~0.4 mil larger than that measured with micro-section; and mainly used for total thickness design calculation.

Laminate Availablity

VT-447(B) Laminates are available in thickness from .003” up to .094” and with the copper foil from 1/4oz to 12oz; Ventec can supply either reverse treated (RT) or double side treated copper foil. DK values are for impedance design.

Core Thickness (Inches) Stack-up Resin Content Dk Df
@ 1GHz @ 5GHz @ 1GHz @ 5GHz
0.003 1-1080 64% 3.85 3.76 0.015 0.016
0.005 1-2116 54% 4.07 3.97 0.014 0.015
0.006 2-1080 64% 3.85 3.76 0.015 0.016
0.008 1-7628 45% 4.34 4.24 0.012 0.013
0.010 2-2116 54% 4.07 3.97 0.014 0.015
0.014 2-7628 41% 4.44 4.34 0.012 0.013
0.016 2-7628 45% 4.31 4.21 0.013 0.014
0.021 3-7628 41% 4.44 4.34 0.012 0.013
0.028 4-7628 41% 4.44 4.34 0.012 0.013
0.031 4-7628 45% 4.34 4.24 0.012 0.013
0.039 5-7628 45% 4.34 4.24 0.012 0.013
0.042 6-7628 41% 4.44 4.34 0.012 0.013

Press Condition

1. Heating rate (Rate of Rise) of material [Material Temperature]: Programmable Press: 1.5-3.0ºC/min (3~5ºF/min). Manual Press:3~6ºC /min (5~10ºF/min)
2. Curing Temperature & Time: >60min at more than 185ºC and peak temperature>195ºC
3. Full Pressure: ≥300psi
4. Vacuuming should be continued until over 140ºC [Material Temperature]
5. Cold Press condition: Keep Plate @ Room Temperature by water; Pressure:100psi; Keep Time:60minutes     

VT-447(B) Hot Start Cycle.jpg

Typical Drilling Parameters

1. Spindle Speed: 120-180 KRPM
2. Feed Rate: 120-220 Inch / min
3. Retract Rate: 596-1000 Inch / min
4. Chip Load: 0.6-2.0 Mil / Rev
5. Entry Board: t0.15mm AI -
6. Stack Amount (t1.6mm): 1-3 stacks -

Desmearing Process

  • Desmear rate of VT-447(B) is less than that of the conventional FR4;
  • Minor adjustments to the desmear process may be necessary for the higher Tg materials;        
  • Check with your chemical supplier for recommendations.

Packaging and baking recommendation

  • It is recommended to bake the board before packaging at 125ºC/4~8h to avoid moisture causing a decrease in heat resistance.
  • If the PCBs needs to be stored for a long time before use, it is recommended to use aluminum foil vacuum packaging.
  • If exceed 3 months after packaging , It is best to bake the PCBs at 125ºC/4~6h before assembly before use.

Downloads for VT-447(B)