Water soluble solder pastes are commonly used for high reliability medical, military and telecom infrastructure applications. Until now, high reliability has had a price-namely poor resistance to variations in temperature and humidity in the print process, and poor resistance to BGA voiding.

1. the product:
A world class
lead free, high
reliability water
soluble paste ®
offering best in ALPHA
class printing,
resistance to BGA
voids and
WS-819
cleanability.
Solder
Paste
product guide
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
1

2. WS-819 solder paste
A world class
lead free, high
Welcome to the
reliability water ALPHA® WS-819 Product Guide
soluble paste CONTENTS
offering best in
class printing, 1. Introduction 3
resistance to BGA 2. Performance Summary 4
voids and
cleanability. 3. Print Performance 5-9
4. Reflow Performance 10 - 19
5. Post Reflow Cleaning 20 - 22
6 . Shelf Life 23
7. Summary 24 - 26
8. Technical Bulletin 27 - 30
9. MSDS 31 - 36
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
2

3. WS-819 solder paste
Introduction
Introducing ALPHA® WS-819,
the state of the art in Water Soluble, Lead Free Solder Paste.
Water soluble solder pastes are commonly used for high reliability medical,
military and telecom infrastructure applications. Until now, high reliability has
had a price-namely poor resistance to variations in temperature and humidity
in the print process, and poor resistance to BGA voiding.
WS-819 was developed to offer the widest possible print process window,
with consistent high print deposit volumes, IPC Class III resistance to voiding,
and ease of cleanability in a ORH0 class solder paste.
As with all Alpha brand products, WS-819 comes with complete process and
product support whenever and however you need us. It’s the kind of support
you would expect from a company that’s remained dedicated to serving the
needs of the Global circuit assembly market for over 50 years.
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
3

4. WS-819 solder paste
Performance Summary
SMT Process Step Performance Indicator WS-819 Performance Capability
Excellent print definition and consistant volumetric performance
Fine Feature Print
to 0.30mm (12 mil) circles and 0.4mm (16 mil) pitch rectangular
Performance
QFP pads.
Stencil Life 8 hours at 35-65% Relative Humidity
Capable of printing in temperatures from 20°C to ≥ 28°C at
Humidity/Temperature Window
Relative Humidities of 50% +-15% (35% to 65%)
Print Process Window
3 to 10 prints per wipe, depending on smallest feature printed,
Stencil Cleaning Frequency
and use of apeture reduction and stencil thickness
25mm/second to 100mm/second (1 inch/second to 4
Print Speed Range inches/second) down to 0.30mm (12 mil) circles and .4mm (16
mil) pitch QFP pads. Optimal results found at 100mm/second.
Solder Spread 88.6% (Average) per JIS-Z-3197:1999 8.3.1.1
Exceeds requirements of IPC 7095 Class lll using soak and
Resistance to Voids ramp reflow profiles on OSP, Immersion Tin, Immersion Silver
and ENIG finishes.
Resistance to Hot and Cold Exceeds the requirements of IPC J-STD-005. No slump at
Reflow Yield
Slump 0.2mm gap per JIS-Z-3284.
Straight Ramp, or <60 second soak profile in air. Nitrogen
Reflow Process Window
recommended for longer (>60 second) soak profiles.
Meets IPC requirements over range of cleaning temperatures
Residue Cleaning
and water pressures, using DI water without additives.
Meets/Exceeds IPC Bellcore and HP EL-EN861-00
Cleanability
Requirements
Post Reflow
J-STD-004 Classification ORH0
Halide Content Halide Free
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
4

5. WS-819 solder paste
8 Hour Stencil Life at High Humidity (66% RH @ 27°C)
PWS0608A #70329576 - 8hr Stencil Life Volume Chart PWS0608A #70329576 - 8hr Stencil Life Volume Chart
BGA56-12 (12 mil Circles) BGA36 (15 mil Circles)
600 Theoretical Volume (565 cubic mils) Condition 900 Theoretical Volume (884 cubic mils) Condition
80F/65-67% RH 80F/65-67% RH
800
500
700
400 600
Volume
Volume
500 55% Trans Effi ciency
300 50% Trans Effi ciency
400
200 300
200
100
100
0 0
Time T-0hr T-1hr T-2hr T-3hr T-4hr T-5hr T-6hr T-7hr T-8hr Time T-0hr T-1hr T-2hr T-3hr T-4hr T-5hr T-6hr T-7hr T-8hr
Condition 80F/65-67% RH Condition 80F/65-67% RH
PWS0608A #70329576 - 8hr Stencil Life Volume Chart PWS0608A #70329576 - 8hr Stencil Life Volume Chart
QFP120-1 (16 mil pitch QFP deposits, 63x10x5 mils) BGA256 (20 mil Circles)
3500 Condition 1600 Theoretical Volume (1571 cubic mils) Condition
Theoretical Volume (3150 cubic mils) 80F/65-67% RH 80F/65-67% RH
3000 1400
2500 1200
70% Trans Effi ciency
1000
Volume
Volume
2000 60% Trans Effi cie
800
1500
600
1000
400
500 200
0 0
Time T-0hr T-1hr T-2hr T-3hr T-4hr T-5hr T-6hr T-7hr T-8hr Time T-0hr T-1hr T-2hr T-3hr T-4hr T-5hr T-6hr T-7hr T-8hr
Condition 80F/65-67% RH Condition 80F/65-67% RH
PWS-0608A was the pre-commercial laboratory name for WS-819
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
5

6. WS-819 solder paste
8 Hour Stencil Life at Low Humidity (23% RH @ 29°C)
PWS0608A #70329576 - 8hr Stencil Life Volume Chart PWS0608A #70329576 - 8hr Stencil Life Volume Chart
BGA56-12 (12 mil Circles) BGA36 (15 mil Circles)
600 Theoretical Volume (565 cubic mils) Condition 900 Theoretical Volume (884 cubic mils) Condition
81-94F/23-25% RH 81-94F/23-25% RH
800
500
700
400 600
Volume
Volume
500 55% Trans Effi ciency
300 50% Trans Effi ciency
400
200 300
200
100
100
0 0
Time T-0hr T-1hr T-2hr T-3hr T-4hr T-5hr T-6hr T-7hr T-8hr Time T-0hr T-1hr T-2hr T-3hr T-4hr T-5hr T-6hr T-7hr T-8hr
Condition 81-94F/23-25% RH Condition 81-94F/23-25% RH
PWS0608A #70329576 - 8hr Stencil Life Volume Chart PWS0608A #70329576 - 8hr Stencil Life Volume Chart
QFP120-2 (16 mil pitch QFP deposits, 56.7x9x5 mils) BGA256 (20 mil Circles)
Theoretical Volume (2552 cubic mils) Condition 1800 Condition
2500 81-94F/23-25% RH 81-94F/23-25% RH
1600 Theoretical Volume (1571 cubic mils)
2000 1400
1200
70% Trans Effi ciency
Volume
Volume
60% Trans Effi ci ency
1500 1000
800
1000
600
400
500
200
0 0
Time T-0hr T-1hr T-2hr T-3hr T-4hr T-5hr T-6hr T-7hr T-8hr Time T-0hr T-1hr T-2hr T-3hr T-4hr T-5hr T-6hr T-7hr T-8hr
Condition 81-94F/23-25% RH Condition 81-94F/23-25% RH
PWS-0608A was the pre-commercial laboratory name for WS-819
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
6

7. WS-819 solder paste
Fine Feature Print Performance Print Process Window
1 inch (25mm) – 4 inches (100 mm)/second1
PWS0608A #70329576 - Volume Repeatability Chart
BGA56-12 (12 mil Circles)
600 Theoretical Volume (565 cubic mils) Print Speed
1 inch/sec.
2 inches/sec.
500 4 inches/sec.
400
Volume
300 50% Trans Effi ciency
200
100
0
Board 1 2 3 4 1 2 3 4 1 2 3 4
Print Speed 1 inch/sec. 2 inches/sec. 4 inches/sec.
1) 5 mil laser cut stencil
PWS-0608A was the pre-commercial laboratory name for WS-819
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
7

8. WS-819 solder paste
Print Process Window
IPC Tack Test
IPC TM-650 2.4.44
Tack Strength (g / sq mm)
Time 25% RH 50% RH 75% RH
Initial 2.8 2.8 2.8
16 hr 3.3 3.0 2.3
24 hr 3.4 3.1 3.0
∆ Tack < 1 unit over 16 hours at all RH
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
8

9. WS-819 solder paste
Print Process Window
Wipe Frequency–
Number of Print Strokes between Stencil Cleaning Step
Paste: ALPHA PWSO608A Lot Number: 70329576
Solder Paste - Wipe Freqency.
Print Parameters: 1 in/s, 1.25 lbs/inch, 0.02 in/s
Number of Bridges Number of Bridges
Board Set 1 Board Set 2
QFP Device QFP Device
Prints 16 (100%) 16 (90%) 20 (100%) 20 (90%) Prints 16 (100%) 16 (90%) 20 (100%) 20 (90%)
1 0 0 0 0 1 0 0 0 0
2 0 0 0 0 2 0 0 0 0
3 0 0 0 0 3 0 0 0 0
4 1 0 2 0 4 0 0 0 0
5 1 0 0 0 5 0 0 0 0
6 0 0 0 0 6 >10 0 0 0
7 3 0 0 0 7 0 0 0 0
8 0 0 0 0 8 0 0 0 0
9 2 0 0 0 9 0 0 0 0
10 0 0 0 0 10 0 0 0 0
Inside Printer Inside Printer
Temperature: 80*F Temperature: 80 F
Relative Humidity: 40 % RH Relative Humidity: 40 % RH
PWS-0608A was the pre-commercial laboratory name for WS-819
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
9

10. WS-819 solder paste
Reflow Yield Yield
Reflow
Reflow Process Guidelines
Parameter Guideline Additional Information
Atmosphere Air (Straight Ramp or < 60 Mass production verification
Second Soak) both in air and N2.
N2 for soak profiles >60
seconds up to 180
seconds
SnAgCu alloy melting ranges. Lower temperature=solidus; SAC305: 217 – 220 ℃ Use for reflow above
higher temperature = liquidus •SAC405: 217 – 225 ℃ liquidus setting
Profile General Guideline (Typical for SAC305)
Setting Zone Optimal Dwell Period Extended window
40oC to 220oC 105 to 180 seconds <210 seconds
130oC to 220oC 90- 100 seconds <135 seconds
170oC to 220oC 60 seconds <90 seconds
TAL (220oC) 45 - 90 seconds 30-90 seconds.
Peak temp. < 240oC for standard OSP <250°C For Entek HT,
finish Immersion Silver,
Immersion Tin or ENIG
finishes
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
10

11. WS-819 solder paste
Reflow Yield
Ramp Profile 1:
0.7C/s 235C Peak 60s TAL
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
11

12. WS-819 solder paste
Reflow Yield
Ramp Profile 2:
1.5C/s 240C Peak 60s TAL
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
12

13. WS-819 solder paste
Soak Reflow Profile: Reflow Yield
175C/60s Soak 240C Peak 60s TAL
(Nitrogen Required for Longer Soak Profiles)
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
13

14. WS-819 solder paste
Reflow Yield
Spread Test Method
JIS-Z-3197:1999 8.3.1.1
Polish the surface of phosphor deoxidized copper plate (50×50×0.5mm) with #500
polishing paper applying drops of alcohol. Wash the surface with alcohol and cool
in room temperature. Subject to oxidizing treatment in a dryer set at 150℃ for 1 hour.
Put approx. 0.3g of solder paste on the center of the copper plate and weigh with
high accuracy.
Place the test panel onto the surface of melted solder in a solder bath set at 250℃.
Keep heating for 30sec. after the solder melts.
Remove the flux residues from the test panels with solvent.
Measure the height of solder with a micrometer and calculate the
spreading rate from the following formula.
S＝[(D-H)/D] ×100 .
S: Spreading Rate(%)
H: Height of Spreading Solder (mm)
D: Diameter of Solder assuming it as a sphere (mm)
D ＝ 1.24 V 1/3
V: Mass / Specific Gravity of Solder
3．Apparatus
Solder Bath POT-200C
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
14

15. WS-819 solder paste
Reflow Yield
Result: 88.6% Spread
Density of Solder Alloy [g/cm] 7.4
A.
Weight of Paste Weight of Solder Height of Solder Spreading Rate Average
Sample
[g] [g] [mm] [%] [%]
#1 0.3206 0.2853 0.384 90.8%
#2 0.3174 0.2825 0.441 89.4%
#3 0.3751 0.3338 0.494 88.8% 88.6%
#4 0.3052 0.2716 0.639 84.5%
#5 0.3332 0.2965 0.442 89.6%
#1 #2 #3 #4 #5
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
15

16. WS-819 solder paste
Reflow Yield
Reflow Yield: Application Note
Definition of Voiding Performance
Solder Outline
Void Outlines
Location of Void Class I Class II Class III
Void in Solder 60% of diameter 42% of diameter 30% of diameter
(Solder Sphere) = 36% of Area = 20.25% of Area = 9% of Area
0.1d
Void at interface of
50% of diameter 25% of diameter 20% of diameter
Solder (Sphere)
= 25% of Area = 12.25% of Area = 4% of Area 0.25d
and Substrate
d
Example:
Total Void Diameter
0.10d +0.25d = 0.35d
IPC Criteria for Voids in BGAs, IPC 7095 7.4.1.6
The IPC criteria provide three classes of acceptance for both the solder sphere and the
sphere-pad interface.
Where multiple voids exist, the dimensions will be added to calculate total voiding in the joint.
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
16

17. WS-819 solder paste
Reflow Yield
Voiding Performance
Void Size Distribution
BGA256
100.00%
90.00%
80.00% WS-819 89.5 M17 Cerf HS 160/60 soak 240Cp
70.00% WS-819 89.5 M17 Cerf St.Ramp 0.7C_S 235Cp.
% of Joints
60.00%
50.00%
40.00%
30.00%
20.00%
10.00%
0.00%
ZERO 0-4% 4-8% 8-12% 12-16% 16-20% >20%
% of Joint area
WS-819 Meets Criteria for Class lll Voiding Using Soak or Ramp Profile
Per IPC 7095 7.4.1.6
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
17

18. WS-819 solder paste
Reflow Yield
Solder Balling Resistance
IPC TM-650 Method 2.4.43
Initial After 4 Hr.
@ 25°C, 50% RH
Both “Preferred” per IPC Standard
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
18

19. WS-819 solder paste
Reflow Yield
Slump Resistance
IPC TM-650 2.4.35
Cold Slump Hot Slump Oven 150C /
25C / 50% / 75% RH 10mins
00.63 x
Pad Size 0.33 x 2.03mm 0.63 x 2.03mm 0.33 x 2.03mm
2.03mm
Largest Gap
No Bridges 0.1 0.41 0.25
Bridged
IPC max gap 0.48 0.2 0.56 0.25
bridge allowed Pass Pass Pass Pass
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
19

20. WS-819 solder paste
Post Reflow Cleaning
Cleanability Study
Boards were built using all five pastes and subsequently cleaned using two
water tem peratures (120 and 150F) and two conveyor speed settings (2
and 5 ft/min) in order to assess the relative cleanability of the pastes. The
pre-wash and wash water pressure were both set at 90 psi, while the rinse
water pressure was set at approximately 70 psi.
IPC J-STD-001 states that the contamination limit for assemblies tested
using the dynamic method of detecting ionic surface contamination
(method used with the Ionograph) is 10 µg/in2 (1.56 µg/cm2) sodium chloride
equivalent ionic or ionizable flux residue.
WS-819 (known as PWS-0608A during the product development process)
showed Ionograph contamination levels of results of 1.10 to 1.58 µg/in2
(0.172 to 0.256 µg/cm2 ), after two reflows and a 48 hour delay before
cleaning, exceeding the IPC requirement under the pressure and
temperature conditions described above
Paste 120F/2.5 ft/min. 120F/5 ft/min. 150F/2.5 ft/min. 150F/5 ft/min.
1.5799 µg/in2 1.1996 µg/in2 1.5106 µg/in2 1.1015 µg/in2
PWS0608A
•Pass Pass Pass Pass
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
20

21. WS-819 solder paste
Post Reflow Cleaning
Post Cleaning Cosmetics
Paste Aged 21 Days in Sealed Container Prior to Reflow
QFP208
High soak profile 160°C, 240°C peak OSP
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
21

22. WS-819 solder paste
Post Reflow Cleaning
Electrical Reliability
IPC SIR 85C / 85% RH, -48 V Bias
SIR (Ω)
Reflow & Cleaning 1 day 4 day 7 day
Ramp 0.7 ° C/sec, 237 ° C peak
Clean 130 ° C, 8 min DI H20 - Req: SIR > 1 x 108 Ω after
Within 2 hours of reflow 9 10 9
2.4 x 10 1.0 x 10 9.9 x 10 4 & 7 days (PASS)
Ramp 0.7 ° C/sec, 237 ° C peak
Clean 130 ° C, 8 min DI H20 -
9 9 9
Delayed 48 hours after reflow 1.4 x 10 2.4 x 10 2.5 x 10
Ionic Cleanliness
Reflow & Cleaning Ionic Contamination (µg/sq in)
Ramp 0.7 ° C/sec, 237 ° C peak
Clean 130 ° C, 8 min DI H20 -
Within 2 hours of reflow
1.36
Req: Ionic contamination <
Ramp 0.7 ° C/sec, 237 ° C peak
10 µg / sq in (PASS)
Clean 130 ° C, 8 min DI H20 -
Delayed 48 hours after reflow
2.43
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
22

23. WS-819 solder paste
Shelf Life
3 Weeks Room Temperature Stability
(25°C; 77°F) in Unopened Container
2500
2000
10 RPM Malcolm Viscosity (KCPS)
1500
WS-819 Viscosity
Upper Limit
Low er Limit
1000
500
6 Month Shelf Life When Stored in Sealed Jar at 1° to 10 ° C (34° to 50° F)
0
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Days After Manufacture
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
23

24. WS-819 solder paste
Summary
Delivers excellent print volume and consistency
• Prints .4mm (16 mil) pitch QFP’s , .3mm (12 mil) circles with Type 3 Powder
• Consistent Print Volume Repeatability at both Low (<35%) and High (65%) Relative Humidity
• 8 Hour Stencil Life at Low and High Humidity
• Excellent post print tack life
• Wide print speed process window (25mm/sec to 100mm/sec)
High Post Reflow Yields
• IPC Class III Voiding Performance (Using Soak Reflow Profile)
• Resistance to cold and hot slump
• Easily Cleaned with Water, after 2 lead free reflow cycles and 48 hour delay
Electrical Reliability
• IPC SIR
• Bellcore SIR
• Bellcore Electromigration
• HP EL-EN861-00 Electromigration
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
24

25. WS-819 solder paste
Summary
Leading Products
No Clean, SnPb
• ALPHA OM-6106
•ALPHA OM-5100
No Clean, Lead-free
• ALPHA OM-338 T
•ALPHA OM-338 PT
• ALPHA OM-350
Water Soluble, SnPb
• ALPHA WS-809
Water Soluble, Lead-free
• ALPHA WS-819
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
25

26. WS-819 solder paste
Summary
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding
the accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of this information or use of any materials designated.
26

27. SM919
ALPHA® WS-819 Water Soluble Lead-Free Solder Paste
DESCRIPTION
ALPHA® WS-819 is the newest Alpha® brand lead free, halide free solder paste offering the ideal combination
of printability under varying environmental conditions, 8 hour stencil life, resistance to BGA voids, high spread
combined with cleanability with water based cleaning systems.
FEATURES & BENEFITS
• Excellent print volume and print volume repeatability down to 12 mil (0.3mm) features
• 8 hour stencil life at 35% to 65% Relative humidity
• High spread/wetting lead free paste compatible with lead free alloys and surface finishes
• High Reflow Yield with IPC Class III Voiding Performance when used to solder BGA components
• Excellent wetting characteristics on all common surface finishes (including Entek HT OSP). JIS Spread 88.6%
on Entek HT OSP.
• Cleanable with water based cleaning systems
PHYSICAL PROPERTIES
• Alloys: SAC305 (96.5%Sn/3.0%Ag/0.5%Cu), SAC405 (95.5%Sn/4.0%Ag/0.5%Cu)
• Application : Stencil printing (89.5% Metal Loading, M-17 Viscosity)
Dispense application (85% Metal Loading, Type 4 Powder, M9 Viscosity)
• Powder Size: Type 3 (25µ-45µ)
• RoHS Status: Completely free of Hazardous Materials per RoHS Directive 2002/95/EC
APPLICATIONS
Alpha® WS-819 was formulated to meet the requirements of water soluble solder lead free applications. Alpha®
WS-819 was developed to offer best in class resistance to heat and humidity variations in the printing process,
while offering exceptional post reflow cleanability and low BGA voiding.
This paste is designed to enable users of Alpha® WS-609; WS-709 and WS-809 and other leading water soluble
paste brands to comply with RoHS and customer based demand for lead free materials.
SAFETY
While the ALPHA® WS-819 flux system is not considered toxic, its use in typical reflow will generate a small
amount of reaction and decomposition vapors. These vapors should be adequately exhausted from the work area.
Consult the MSDS for additional safety information.
SHIPPING AND STORAGE
ALPHA® WS-819 is shipped in thermally controlled boxes and should be stored refrigerated upon receipt at 340 -
450F (10 - 70C). ALPHA® WS-819 should be permitted to reach room temperature before opening the package
prior to use.
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding the
accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of the use of this information or the use of any materials designated.
5-9-07
14 Tuas Avenue 10, Singapore 639138, 65-68611977, www.alphametals.com

28. ALPHA® WS-819 TECHNICAL DATA
Physical Properties
Items ALPHA® WS-819 SAC 305/405 Test Method
89.5-3-M17 (stencil printing)
Appearance (flux residues after reflowed) Light yellowish color (before water washed) CEAMG PUT 001.05
Metal content (%) 89.4% +- 0.2% CEAMG STM 0355
Viscosity (Poise, Malcom spiral viscometer M17 for stencil printing CEAMG STM 0541
@10rpm) M9 for dispensing
Stencil life (50%+- 15%RH, 25°C) >8 hours CEAMG PUT 001.01
Printability Suitable for fine pitch printing applications (Down CEAMG PUT 001.01
to 16 mil (0.4mm) pitch QFP components, 12 mil
(0.3mm) BGA circles @) up to 100 mm/sec
squeegee speed, using 5 mil (125µ) thick laser
cut stencil
Response to pause 0-1 Knead Stroke Required CEAMG PUT 001.08
Tack Initial 2.0 g/mm²; 1.8 g/mm² after 4 hours at 25°C IPC TM-650 2.4.44
and 50% R.H.
Random Solder Balls Preferred (Both Initial and after 4 hours at 25°C IPC TM-650 2.4.43
and 50% R.H.
Slump Resistance Pass IPC TM-650 2.4.35
Chemical Properties
Items ALPHA® WS-819 Flux System
Halide content (IPC J-Std-004) ORH0
Corrosivity (IPC J-Std-004) Not applicable for water soluble solder paste
ALPHA® WS-819 PROCESSING GUIDELINES
STORAGE-HANDLING PRINTING / DISPENSING REFLOW CLEANING
• Refrigerate to guarantee stability @ STENCIL: Recommend ALPHA CUT ATMOSPHERE: • ALPHA WS-819 is designed
34-45°F (1-7°C) Laser Cut Stencil @ 0.005 inch (5 • Clean-dry air to be water rinsed in washing
mil, 127µ) thick for 0.012 inch (.30 If soak temp ≥ 160°C) and soak operations. with minimal
• Warm-up of 500g jar to room foaming in recirculating
mml) pitch QFPs time > 45-60 seconds Nitrogen
temperature (should be ~ 6 hours). systems.
recommended for longer soak
Set up printer with room
SQUEEGEE: Metal (Recommended) profiles (60 to 180 seconds).
temperature paste. Check paste • The flux residues from
temperature with a thermometer. •
ALPHA WS-819 are
PROFILE (PRINTING): completely water soluble.
• Do not remove worked paste from Print Speed: 2.0 -4.0 in./sec (50-100
• See profiles evaluated in This allows for more flexible
stencil and mix with unused paste mm/sec.) 4.0 in/sec. optimal
product development below washing conditions which can
in jar. This will alter rheology of o be board design specific.
unused paste. SQUEEGEE: Pressure: 1.5 to 2.0 • Slow ramp from 130 C to
o
lbs./ linear in. (0357 Kg/cm) 180 C for 90~120 seconds
o • If lower/no foaming is desired
• Do not shake or mix paste using • Ramp @ 0.5~2 C/sec to peak
o o in cleaning equipment, Alpha
automatic paste shaking equipment Stencil Release Speed: .02 in/sec temperature 230 C - 250 C
P-2000 defoamer may be
prior to opening jar. The plunger (0.5 mm/second) TAL for 40~80 seconds.
used.
insert used may submerge into • Ramp down to R.T. @
o
paste and produce difficulties with Compatible with DEK Pro-Flow 1~3 C/sec.
plunger removal. Enclosed print head. Report
available upon request.
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding the
accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of the use of this information or the use of any materials designated.
5-9-07

29. Reflow Profiles Tested, using Clean, Dry Air
CERF Straight Ramp 0.7C/s 235C Peak 60s TAL
CERF Straight Ramp 1.5C/s 240C Peak 60s TAL
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding the
accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of the use of this information or the use of any materials designated.
5-9-07

30. CERF 60s Soak @ 175°C/ 240C Peak 60s TAL
Note- profiles using a soak time > 60 seconds may require nitrogen for satisfactory results Use of air for long soak
profiles have resulted in dull, grainy joints, and possible de-wetting of solder joints.
The information contained herein is based on data considered accurate and is offered at no charge. No warranty is expressed or implied regarding the
accuracy of this data. Liability is expressly disclaimed for any loss or injury arising out of the use of this information or the use of any materials designated.
5-9-07

31. Page 1 of 6
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DATA SHEET
MSDS ID: AA 00151090
1. CHEMICAL PRODUCT AND COMPANY IDENTIFICATION
PRODUCT NAME: ALPHA WS-819 SOLDER PASTE SAC305 & SAC405
MANUFACTURER'S NAME: ALPHA METALS, INC
ADDRESS: 600 ROUTE 440
JERSEY CITY, NJ 07304
TRANSPORT EMERGENCY #: CHEMTREC: 1-800-424-9300
BUSINESS PHONE: 1-201-434-6778
2. INGREDIENT AND EXPOSURE LIMIT INFORMATION
CHEMICAL NAME CAS # % W/W OSHA PEL - TWA
TIN 7440-31-5 80 - 90 2.0 mg/m3
SILVER 7440-22-4 1 - 5 0.01 mg/m3
COPPER 7440-50-8 0.2 - 1 0.1 mg/m3 (fume)
Ethoxylated-N-Tallow 61790-85-0 1 - 3 NE
Alkyltrimethylenediamine
FORAL AX 65997-06-0 1 - 3 **
Ethoxylated octylphenol 9002-93-1 1 - 5 NE
**SENSITIZER
3. HAZARDS IDENTIFICATION
EMERGENCY OVERVIEW: MODERATE EYE IRRITANT.
WILL NOT BURN
TOXIC BY INHALATION.
MODERATE GASTROINTESTINAL TRACT IRRITANT.
MODERATE RESPIRATORY TRACT IRRITANT.
CAUSES SKIN IRRITATION
HMIS RATING SYSTEM:
Health: 1 ; Flammability: 0 ; Reactivity: 0 ; Protection: C
NFPA RATING SYSTEM:
Health: 2 ; Flammability: 0 ; Reactivity: 0
ROUTES OF ENTRY: INHALATION; INGESTION; SKIN CONTACT; EYE CONTACT;
ABSORPTION;
TARGET ORGANS: BLOOD; DIGESTIVE TRACT; KIDNEYS; NERVOUS SYSTEM; EYES;
SKIN.
MEDICAL CONDITIONS AGGRAVATED: DIGESTIVE TRACT DISEASE; KIDNEY DISEASE
EYE DISEASE. SKIN DISEASE INCLUDING ECZEMA
AND SENSITIZATION.
IMMEDIATE (ACUTE) SYMPTOMS OVER-EXPOSURE BY ROUTE OF EXPOSURE:
INHALATION: CAN CAUSE MODERATE RESPIRATORY IRRITATION, DIZZINESS,
WEAKNESS, FATIGUE, NAUSEA AND HEADACHE. MAY CAUSE AN

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3. HAZARDS IDENTIFICATION (Cont.)
ALLERGIC REACTION. MAY CAUSE RESPIRATORY TRACT
SENSITIZATION, CHARACTERIZED BY ASTHMA-LIKE SYMPTOMS.
EYES: CAN CAUSE MODERATE IRRITATION, TEARING AND REDDENING, BUT
NOT LIKELY TO PERMANENTLY INJURE EYE TISSUE.
SKIN CONTACT: CAN CAUSE SLIGHT IRRITATION.
INGESTION: IRRITATING TO MOUTH, THROAT, AND STOMACH. CAN CAUSE
ABDOMINAL DISCOMFORT, NAUSEA, VOMITING AND DIARRHEA.
LONG TERM (CHRONIC) HEALTH EFFECTS:
CARCINOGENICITY: NONE OF THE SUBSTANCES HAVE BEEN SHOWN TO CAUSE CANCER IN
LONG TERM ANIMAL STUDIES. NOT A CARCINOGEN ACCORDING TO NTP,
IARC, OR OSHA.
REPRODUCTION: NO DATA AVAILABLE TO INDICATE PRODUCT OR ANY COMPONENTS
PRESENT AT GREATER THAN 0.1% MAY CAUSE BIRTH DEFECTS.
MUTAGENICITY: NO DATA AVAILABLE TO INDICATE PRODUCT OR ANY COMPONENTS
PRESENT AT GREATER THAN 0.1% IS MUTAGENIC OR GENOTOXIC.
4. FIRST AID MEASURES
SKIN EXPOSURE: WASH WITH SOAP AND WATER. REMOVE CONTAMINATED CLOTHING AND
LAUNDER. GET MEDICAL ATTENTION IF IRRITATION DEVELOPS OR
PERSISTS.
EYE EXPOSURE: FLUSH EYES WITH PLENTY OF WATER FOR AT LEAST 20 MINUTES
RETRACTING EYELIDS OFTEN. TILT THE HEAD TO PREVENT CHEMICAL
FROM TRANSFERRING TO THE UNCONTAMINATED EYE. GET IMMEDIATE
MEDICAL ATTENTION.
INHALATION: REMOVE TO FRESH AIR. IF BREATHING IS DIFFICULT, HAVE A
TRAINED INDIVIDUAL ADMINISTER OXYGEN. IF NOT BREATHING, GIVE
ARTIFICIAL RESPIRATION AND HAVE A TRAINED INDIVIDUAL
ADMINISTER OXYGEN. GET MEDICAL ATTENTION IMMEDIATELY
INGESTION: SEEK MEDICAL ATTENTION IMMEDIATELY.
NOTES TO DOCTOR: NO ADDITIONAL FIRST AID INFORMATION AVAILABLE
5. FIRE FIGHTING MEASURES
FLAMMABILITY SUMMARY: NOT COMBUSTIBLE
FLASH POINT: N/A
AUTOIGNITION TEMPERATURE: N/E
EXPLOSIVE LIMITS % IN AIR: N/E
EXTINGUISHING MEDIA: USE ALCOHOL RESISTANT FOAM, CARBON DIOXIDE, OR
DRY CHEMICAL WHEN FIGHTING FIRES. WATER OR
FOAM MAY CAUSE FROTHING IF LIQUID IS BURNING
BUT IT STILL MAY BE USEFUL EXTINGUISHING AGENT
IF CAREFULLLY APPLIED TO THE SURFACE OF THE
FIRE. DO NOT DIRECT A STREAM OF WATER INTO

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5. FIRE FIGHTING MEASURES (Cont.)
MOLTEN MATERIAL.
FIRE AND EXPLOSION METHODS: MATERIAL MAY BE IGNITED ONLY IF PREHEATED TO
TEMPETURES ABOVE THE HIGH FLASH POINT, FOR
EXAMPLE IN A FIRE. DUST AT SUFFICIENT
CONCENTRATIONS CAN FORM EXPLOSIVE MIXTURES
WITH AIR.
FIRE FIGHTING METHODS: WILL NOT BURN, NO SPECIAL INSTRUCTIONS
AVAILABLE. USE METHODS APPROPRIATE FOR
SURROUNDING MATERIALS.
HAZARDOUS COMBUSTION PRODUCTS: CARBON MONOXIDE; CARBON DIOXIDE; METAL FUMES;
TOXIC FUMES.
6. ACCIDENTAL RELEASE MEASURES
PRECAUTIONS AND EQUIPMENT: EXPOSURE TO THE SPILLED MATERIAL MAY BE IRRITATING
OR HARMFUL. FOLLOW PERSONAL PROTECTIVE EQUIPMENT
RECOMMENDATIONS FOUND IN SECTION VIII OF THIS
MSDS.
METHODS FOR CLEAN-UP: WEAR COMPLETE AND PROPER PERSONAL PROTECTIVE
EQUIPMENT FOLLOWING THE RECOMMENDATION OF SECTION
VIII GATHER AND STORE IN A SEALED CONTAINER
PENDING A WASTE DISPOSAL EVALUATION. DO NOT USE
BROOM OR AIR CLEANING ETC.
7. HANDLING AND STORAGE
HANDLING MEASURES: HARMFUL OR IRRITATING MATERIAL. AVOID CONTACTING AND AVOID
BREATHING THE MATERIAL. USE ONLY IN A WELL VENTILATED
AREA.
AS WITH ALL CHEMICALS, GOOD INDUSTRIAL HYGIENE PRACTICES
SHOULD BE FOLLOWED WHEN HANDLING THIS MATERIAL. AVOID
CONTACT WITH MATERIAL, AVOID BREATHING DUSTS OR FUMES, USE
ONLY IN A WELL VENTILATED AREA. WASH THOROUGHLY AFTER
HANDLING; WASH HANDS BEFORE EATING; DO NOT GET IN EYES,
ON SKIN AND CLOTHING; MINIMIZE DUST GENERATION AND
ACCUMULATION; AVOID CREATING DUSTS AS AN EXPLOSIVE
HIGH CONCENTRATIONS.
STORAGE MEASURES: NO SPECIAL REQUIREMENTS
KEEP AWAY FROM FOOD AND DRINKING WATER. STORE IN A COOL
DRY PLACE.

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8. EXPOSURE CONTROLS AND PERSONAL PROTECTION
ENGINEERING MEASURES: USE LOCAL EXHAUST VENTILATION OR OTHER ENGINEERING
CONTROLS TO MINIMIZE EXPOSURES AND MAINTAIN OPERATOR
COMFORT.
ENGINEERING CONTROLS MUST BE DESIGNED TO MEET THE
OSHA CHEMICAL SPECIFIC STANDARD IN 29 CFR 1910.
VENTILATION IS REQUIRED TO MAINTAIN OPERATOR EXPOSURE
BELOW PUBLISHED EXPOSURE LIMITS. USE PROCESS
ENCLOSURES, LOCAL EXHAUST VENTILATION, OR OTHER
ENGINEERING CONTROLS TO CONTROL AIRBORNE LEVELS BELOW
RECOMMENDED EXPOSURE LIMITS; EXPLOSION PROOF EXHAUST
VENTILATION SHOULD BE USED. FACILITIES STORING OR
USING THIS MATERIAL SHOULD BE EQUIPPED WITH AN
EYEWASH AND SAFETY SHOWER.
RESPIRATORY PROTECTION: RESPIRATORY PROTECTION MAY BE REQUIRED TO AVOID
OVEREXPOSURE WHEN HANDLING THIS PRODUCT. GENERAL OR
LOCAL EXHAUST VENTILATION IS THE PREFERRED MEANS OF
PROTECTION. USE A RESPIRATOR IF GENERAL ROOM
VENTILATION IS NOT AVAILABLE OR SUFFICIENT TO
ELIMINATE SYMPTOMS.
FOLLOW A RESPIRATORY PROTECTION PROGRAM THAT MEETS 29
CFR 1910.134 AND ANSI Z88.2 REQUIREMENTS WHENEVER
WORK PLACE CONDITIONS WARRANT THE USE OF A
RESPIRATOR. WEAR A NIOSH APPROVED RESPIRATOR IF ANY
EXPOSURE IS POSSIBLE.
EYE PROTECTION: WEAR CHEMICALLY RESISTANT SAFETY GLASSES WITH SIDE
SHIELDS WHEN HANDLING THIS PRODUCT. DO NOT WEAR
CONTACT LENSES.
WEAR GOGGLES AND A FACE SHIELD
SKIN PROTECTION: WEAR PROTECTIVE GLOVES. INSPECT GLOVES FOR CHEMICAL
BREAK-THROUGH AND REPLACE AT REGULAR INTERVALS. CLEAN
PROTECTIVE EQUIPMENT REGULARLY. WASH HANDS AND OTHER
EXPOSED AREAS WITH MILD SOAP AND WATER BEFORE EATING,
DRINKING, AND WHEN LEAVING WORK
CONTROL PARAMETERS: ----------ACGIH EXPOSURE LIMITS----------------
CHEMICAL NAME TLV-TWA STEL CEILING
Forax AX Sensitizer;keep
exposure as low
as possible.
TIN 2 mg/m3 TWA
SILVER 0.01 mg/m3 TWA
COPPER 0.1 mg/m3 TWA (fume)

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9. PHYSICAL AND CHEMICAL PROPERTIES
COLOR: GREY
ODOR: NONE
pH: N/A
10. STABILITY AND REACTIVITY
DECOMPOSITION PRODUCTS: METAL FUMES; TOXIC FUMES.
INCOMPATIBLE MATERIALS: STRONG ACIDS; STRONG OXIDIZING AGENTS;
CONDITIONS TO AVOID: NONE KNOWN
CONTAMINATION: CONTACT WITH AIR. CONTACT WITH
WATER
11. TOXICOLOGICAL INFORMATION
COMPONENT TOXICOLOGY DATA (NIOSH)
CHEMICAL NAME LD50/LC50
Ethoxylated octylphenol Acute oral toxicity (LD50):1800 mg/kg(Rat)
Ethoxylated-N-Tallow LD50: 945 mg/kg oral rat
Alkyltrimethylenediamine
Floral AX Sensitizer
12. ECOLOGICAL INFORMATION
OVERVIEW: SLIGHT ECOLOGICAL HAZARD. IN HIGH CONCENTRATIONS, THIS
PRODUCT MAY BE DANGEROUS TO PLANTS AND/OR WILDLIFE.
13. DISPOSAL CONSIDERATIONS
WASTE DESCRIPTION: SPENT OR DISCARDED MATERIAL IS PROBABLY A HAZARDOUS WASTE.
DISPOSAL METHODS: DISPOSE OF IN ACCORDANCE WITH FEDERAL, STATE, LOCAL, OR
PROVINCIAL LAWS AND REGULATIONS.

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14. TRANSPORT INFORMATION
SHIPPING BASIC DESCRIPTION: DOT & IATA: NOT RESTRICTED
15. REGULATORY INFORMATION
TSCA STATUS: ALL COMPONENTS OF THIS PRODUCT ARE LISTED ON THE TSCA INVENTORY
OF EXISTING CHEMICAL SUBSTANCES.
REGULATED CHEMICALS:
CHEMICAL NAME REGULATION
SILVER 7440-22-4 SARA 313
WHMIS rating: D2B
16. OTHER INFORMATION
The information contained herein is based on data considered accurate.
However, no warranty is expressed of implied regarding the accuracy of these
data or the results to be obtained from the use thereof. Additionally, Alpha
Metals, Inc. assumes no responsibility for injury to the vendee or third
persons proximately caused by the material even if reasonable safety
procedures are followed. Furthermore, vendee assumes the risk in his use of
the material.