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## Desiccating agent consumption calculation

### Calculation method by JIS Z 0301

The desiccating agent, please find the consumption by the following expressions depending on a use and the situation.

(1)

W: Consumption (g) of the desiccating agent
R: Of JIS Z 0208 [vapor permeance test method (cup method) of the moisture-proof wrapping]
Vapor permeance (g/m2, 24h) of the moisture-proof wrapping by condition B
A: Surface area (m2) of the moisture-proof packing
t: Packing period Sunday (= 24h) (1)
h1: Mean humidity (%) of the fresh air during a packing period
h2: Mean humidity (%) (2) in the packing during a packing period
K1: Moisture-proof wrapping coefficient (3) to be decided by kind and average temperature θ ℃ during a packing period
C1: Moisture absorption rate (%) of the desiccating agent at the time of the beginning to use
C2: Equilibrium moisture absorption rate (%) of the desiccating agent in the relative humidity of the maximum permitted by the packing inside
K2: Wrapping coefficient (4) to be decided by a moisture absorption rate with the absorbency in the packing
D: Mass (g) of the wrapping with the absorbency in the packing

 Note (1) When a change of temperature, the humidity during a packing period is big, you divide a packing period properly and calculate the desiccating agent consumption during each period and may add this. (2) For kisanchi, I take the middle value with the humidity of the maximum permitted within humidity and packing in the early packing. (3) I calculate the value of K1 by the next expression. Pθ: I can put it in mean temperature θ ℃ during a packing period         Moisture-permeable rate (g, cm/cm2, s, kPa) of the moisture-proof wrapping P40: Moisture-permeable rate (g, cm/cm2, s, kPa) of the moisture-proof wrapping in 40 degrees Celsius pθ: I divide saturated steam in θ ℃ (kPa) p40: I divide saturated steam in 40 degrees Celsius (kPa)

I show a value of K1 in various temperature of the film for the reference ... a lot of packing to the reference list.
 Film 40 degrees Celsius 35 degrees Celsius 30 degrees Celsius 25 degrees Celsius 20 degrees Celsius 15 degrees Celsius 10 degrees Celsius 5 degrees Celsius Polyester 11.1 x 10-3 7.3 x 10-3 4.9 x 10-3 3.1 x 10-3 2.0 x 10-3 1.27 x 10-3 0.81 x 10-3 0.48 x 10-3 Low density Polyethylene 11.1 x 10-3 7.0 x 10-3 4.5 x 10-3 2.8 x 10-3 1.8 x 10-3 1.05 x 10-3 0.63 x 10-3 0.36 x 10-3 High density Polyethylene 11.1 x 10-3 6.9 x 10-3 4.4 x 10-3 2.7 x 10-3 1.7 x 10-3 1.0 x 10-3 0.59 x 10-3 0.33 x 10-3 Polypropylene 11.1 x 10-3 6.9 x 10-3 4.3 x 10-3 2.5 x 10-3 1.6 x 10-3 0.92 x 10-3 0.53 x 10-3 0.29 x 10-3 Polychlorination Vinylidene 11.1 x 10-3 6.5 x 10-3 3.9 x 10-3 2.2 x 10-3 1.3 x 10-3 0.74 x 10-3 0.40 x 10-3 0.21 x 10-3
 Note (4) I calculate K2 by the next expression. C1: Moisture absorption rate (%) of the desiccating agent at the time of the packing start C2: Equilibrium moisture absorption rate (%) of the desiccating agent in the humidity of the maximum permitted within packing C3: Equilibrium moisture absorption rate (%) of the wrapping with the absorbency in the humidity of the maximum permitted within packing C4: Moisture absorption rate (%) of the wrapping with the absorbency when I put it in the packing

(2)
I calculate R = 0, the consumption of the desiccating agent at the age of D = 0 by the next expression.
V: The space capacity (m3) in the packing container except the capacity of the packing contents
H: Absolute humidity (g/m3) in the temperature-humidity at the time of the packing
C1: Moisture absorption rate (%) of the desiccating agent at the time of the packing start
C2: Equilibrium moisture absorption rate (%) of the desiccating agent in the humidity of the maximum permitted within packing