 PAINT
batches
Paint manufacturers generally produce large amounts of paint at
once in a quantity referred to as a ‘batch.’ The actual size of
each batch varies with the type of product, manufacturing method,
and consumer demand. A manufacturer who specializes in trade sales
and architectural paints may be set up to produce larger batches
(500-20,000 gallons) of a high-demand paint such as flat latex,
and smaller amounts (100-200 gallons) of a less commonly used
product, such as gloss blue equipment enamel.
For each batch of paint, a batch "ticket" or "card" is used. This can include the ingredient list that includes the specific material, weight, volume, and order of addition, along with the manufacturing procedure and process tests required. Areas are often left on the cards for comments from the batch maker or the quality control personnel.
Sample of a 'Batch Card'
| Product |
Super X Flat Latex |
Batch No. |
xxxx |
| Volume |
100 Gallons |
|
|
| Date |
08 17 98 |
|
|
| Operator |
Bob |
|
|
| Equipment |
25 Hp disperser # 2 |
|
| Material |
Weight |
Volume |
| |
|
|
| Water |
416.5 |
50 |
| Preservative |
0.5 |
|
| Cellulose based thickener |
10 |
|
| >>>>Disperse 10 minute, then add slowly |
|
|
| |
|
|
| Ammonia 28% |
0.25 |
|
| |
|
|
| >>>>Increase speed of mixer, 900rpm, mix 5 minutes then add: |
|
|
| Ethylene Glycol |
20.0 |
|
| Dispersant |
5.5 |
|
| Surfactant |
1.0 |
|
| Defoamer |
0.5 |
|
| Titanium Dioxide |
200 |
|
| Calcined clay |
200 |
|
| Calcium Carbonate |
150 |
|
| |
|
|
| >>>>Disperse to 4 hegman grind |
|
|
| >>>>Slow mixer to 300 rpm adjust height to maintain vortex |
|
|
| >>>>Then add slowly: |
|
|
| |
|
|
| Acrylic emulsion (50%) |
250 |
|
| |
|
|
| >>>>Mix uniformly then add: |
|
|
| |
|
|
| Co-solvent |
8.0 |
|
| Defoamer |
1.5 |
|
| Surfactant |
2.0 |
|
| Water |
41.6 |
5 |
|
| Quality Control |
|
|
|
|
|
| |
|
|
|
|
|
| Test |
Std |
Result |
Test |
Std |
Result |
| Viscosity |
70 – 80 |
80 KU |
Grind |
4 |
4+ |
| PH |
8.0 – 8.5 |
7.9 |
Gloss |
0 – 10 |
5 |
| Dry Time |
4 hrs. |
3.5 hrs |
Weight/Gallon |
13.15 +/- 0.1 |
13.17 |
| Defoaming |
5 min. |
Good |
Color Acceptance |
No rub |
good |
|
| |
Each batch of paint is tested, coded, and packaged as a separate material. This helps track the date of manufacture and the extent of the quality control used if there is a problem later with the product. Most manufacturers keep "retains," which are small amounts taken from each batch to keep as ‘controls should the batch later be accused of being ‘faulty.’ Testing the retains against the ‘faulty’ sample can verify that the batch was fine when manufacturered, and that the paint may have been improperly stored, frozen, or adulterated after it was shipped to the customer or jobsite.
Special Note: Each batch of paint is given a specific batch number. There can be notable differences in properties between batches of a particular product, so whenever possible, material from a single batch should be used on a job. In no case should material from a different batch be used for "touch-up." |
