Home   |  Site Map  |  Contact Us
Quality Control Instruments Since 1936 • 1-800-762-2478
Social Media
Facebook Twitter YouTube Google + Blogger
Home > Products > Application > PFUND Cryptometer
Special Offer PFUND Cryptometer

The hiding and spreading powers of pigmented coatings are of fundamental importance and there are many methods by which the opacity of a coating may be examined. These methods do not relate necessarily to painting practice as the change of appearance wanted, the contour and surface characteristics of the substrate together with the rheological properties of the paint will influence the performance of such coatings.

The cryptometer was developed to provide a simple and rapid subjective test method for the determination of opacity in terms of hiding and spreading powers; its popularity continues for production and quality control purposes in preference to comprehensive practical testing and the complex measurement of reflectance values. Their use is called for in some product specifications and national test methods which accept the limitations that the wet film and not the dry coating is being measured.

302 Cyprtometers

The instrument consists of a glass plate, half black half white, as the base. Each half of this base has a scale engraved from 0 - 50 mm along one edge starting from the division in the center. Two glass top plates are included, usually with each instrument, and these have two metal supports at one end so that these transparent top plates rest at an angle when placed upon the black and white area of the base plate. The top plates differ in the length of their tiny supports so that different angles are formed between the top plates and the base plate. A wedge angle constant (K) is given to each top plate. These range from the smallest angle K = 002 to K = .0035, K = .004, K = .007 and the largest K = .008, the popular constants being K = .004 and K = .008.

Method of Use
The appropriate top plate for the paint to be tested is selected, usually K = .008 for light colored paints and K = .004 for dark colored paints. A blob of paint is placed in the center of the base plate close to the black / white division. For light colors the top plate, e.g. K = .008, is placed over the paint with the supports on the white area of the tile. The top plate is pressed down firmly so that the paint is spread without air bubbles to form a shallow wedge between the plates. This wedge will move with the top plate, the position of which is adjusted until it is observed that the black/white division is just obliterated. The scale reading is then noted from the black scale where the edge of the top plate makes contact with the base plate. When testing a dark colored paint the top plate, e.g. K = .004, is used and the scale reading taken on the white area.

Coverage in Square Meters per Liter
The thickness of paint in millimeters over the black and white division is obtained by multiplying the scale reading times the wedge constant K of the top plate used. This figure records the minimum film thickness necessary to obliterate over black and white. The coverage or spreading power for this thickness can be obtained directly from the conversion charts below for each of the top plates.

Technical Data
K=.004
  0 1 2 3 4 5 6 7 8 9
0 50.0 41.6 35.6 31.6 27.7
10 25 22.7 20.6 19.2 17.8 16.6 15.6 14.7 13.9 13.1
20 12.5 11.9 11.3 10.9 10.4 10.0 9.6 9.25 8.9 8.6
30 8.33 8.05 7.8 7.55 7.3 7.1 6.92 6.74 6.66 6.4
40 6.24 6.08 5.94 5.8 5.66 5.55 5.42 5.3 5.2 5.1
K = .008
  0 1 2 3 4 5 6 7 8 9
0 25.0 20.6 17.8 15.6 13.9
10 12.5 11.3 10.4 9.6 8.9 8.33 7.8 7.3 6.92 6.66
20 6.24 5.94 5.66 5.42 5.2 5.0 4.8 4.63 4.47 4.3
30 4.16 4.02 3.9 3.77 3.65 3.55 3.45 3.36 3.28 3.2
40 3.12 3.04 2.96 2.9 2.84 2.78 2.71 2.65 2.59 2.55
K = .002
  0 1 2 3 4 5 6 7 8 9
0
10 49.9 45.3 41.6 38.4 35.6 33.3 31.9 29.3 27.7 26.3
20 25.0 23.8 22.7 21.7 20.8 19.9 19.2 18.4 17.8 17.2
30 16.7 16.1 15.6 15.1 14.7 14.2 13.8 13.5 13.1 12.8
40 12.5 12.2 11.9 11.6 11.4 11.1 10.9 10.6 10.4 10.2
K = .0035
  0 1 2 3 4 5 6 7 8 9
0 57.1 47.4 40.8 35.6 31.6
10 28.6 25.9 23.8 21.9 20.4 19.0 17.8 16.7 15.8 15.0
20 14.3 13.6 12.9 12.4 11.9 11.4 11.0 10.6 10.2 9.9
30 9.5 9.2 8.9 8.7 8.4 8.1 7.9 7.7 7.5 7.3
40 7.1 6.9 6.8 6.6 6.5          
K = .007
  0 1 2 3 4 5 6 7 8 9
0 28.6 23.7 20.4 17.8 15.8
10 14.3 13.0 11.9 11.0 10.2 9.5 8.9 8.4 7.9 7.5
20 7.1 6.8 6.4 6.2 6.0 5.7 5.5 5.3 5.2 4.9
30 4.8 4.6 4.4 4.3 4.2 4.1 3.9 3.8 3.8 3.7
40 3.6 3.5 3.4 3.3 3.2 3.2 3.1 3.0 3.0 2.9
  • To convert coverage from square meters per liter to square feet per imperial gallon, multiply by 49.
  • To convert from square meters per liter to square feet per US gallon, multiply by 40.7.
  • After use, both plates should be cleaned carefully with the solvent appropriate to the paint under test. Do not immerse the base plate in strong solvents, e.g. ketones, chlorinated hydrocarbons, etc., for protracted lengths of time.

Available Items - Literature
Prices subject to change    Prices listed in US dollars for domestic shipments within US, Canada, & Mexico only    Export orders require quotations - click here for a quote     For more info call us 1-800-762-2478 or 954-946-9454.
Item Number Item Prices
Domestic Shipping is FREE on the Product of the Month
CR-200302 Product of the Month Sale - Black & White Cryptometer with two plates, with Certificate of Conformity, K = .002 and K = .007 Now $1,795.50
Was $1,995.00
CR-200312 Extra top plate, K = .002, 6.7” x 6.7” x 1.19” (17 x 17 x 3 cm) 1.78 lbs (800 grams) 350.00
CR-200314 Extra top plate, K = .004, 6.7” x 6.7” x 1.19” (17 x 17 x 3 cm) 1.78 lbs (800 grams) 350.00
CR-200318 Extra top plate, K = .008, 6.7” x 6.7” x 1.19” (17 x 17 x 3 cm) 1.78 lbs (800 grams) 350.00
CR-200313 Extra top plate, K = .0035, 6.7” x 6.7” x 1.19” (17 x 17 x 3 cm) 1.78 lbs (800 grams) 350.00
CR-200317 Extra top plate, K = .007, 6.7” x 6.7” x 1.19” (17 x 17 x 3 cm) 1.78 lbs (800 grams) 350.00

Cryptometer

Gardco
  About Us Products Product Info/Sales Useful Links Quotes/Ordering
History Browse by Industry New Products Trade Shows How to Order
Contact Info Categories Product of the Month FAQ's Request a Quote
Sitemap   Sales & Clearance Test Lab Info Secure Order Form
Policies   Product Videos Social Media Customer Survey
Testimonials   Groups/Prefixes Register for Updates  
Top
 
© Paul N. Gardner Company, Inc. 1.800.762.2478