Applications For Solder Paste
Solder paste is typically used in the large-scale manufacturing of PCBs, or prototype production. It is used in conjunction with a reflow oven or machine in the PCB assembly process.
This type of solder often provides a great, easy-to-use medium for solder, being used in most forms of SMTs.
What Is Solder Paste?
Solder paste is essentially powdered solder that is mixed with a flux material. It is applied to surface mount boards, prior to the either machine or manual pick and place process.
The flux that is in the paste will temporarily hold a component onto a board. When heat is then applied (usually through a reflow machine), the paste melts and creates a strong physical bond. Solder paste comes in the form of either a lead or tin alloy, whilst also requiring a stencil for applying to a PCB.
How To Store Your Solder Paste
To ensure that your solder paste retains the required properties for your application, you must store solder paste in the correct environment – prolonging it’s shelf life.
Firstly, it needs to be stored in an air tight container. This helps to prevent any possible oxidisation from occurring.
It must also be stored at a low temperature, which further aids in preventing oxidisation. Cold temperatures also help to reduce the degradation rate of the flux within the solder paste. Please ensure that the temperature the paste is stored at is not below freezing.
IPC Type & Particle Size
Solder paste is graded as per the size of small solder balls, into different type designations. This is not an exact process, so the Type designations display a range whereby 80% of the solder balls within the paste fall between. See table below:
| IPC Type Designation |
Particle Size (mm) |
| Type 1 |
75 - 150 |
| Type 2 |
45 - 75 |
| Type 3 |
25 - 45 |
| Type 4 |
20 - 38 |
| Type 5 |
10 - 25 |
| Type 6 |
5 - 15 |
| Type 7 |
2 - 11 |
| Type 8 |
2 - 8 |
Variations Of Solder Paste
Rosin Based – Made from a natural extract from pine trees, rosin. Can be cleaned if required after the soldering process, using a solvent (see Ambersil products).
Water Soluble Flux Based Solder Paste – A water-soluble flux, made from organic materials & glycol bases. There are many options for cleaning agents for these fluxes.
No Clean Solder Paste – Comprised of resins & various levels of solid residue. They save you cleaning costs, capital expenditure & floor space.
Contact Kaisertech For Solder Paste Requirements
Should you require any assistance with solder paste, contact our team today and we can help with any kind of bespoke requirements you may have.
