US4257995A
Expired / Lapsed
US
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Process for preparing particle board and polyisocyanate-phosphorus compound release agent composition therefor
Assignee: Dow Chemical Co
•
Filing: 1980-03-26
•
Granted: 1981-03-24
•
Expires: 2000-03-26
Abstract
Abstract The use of polyisocyanates as binders in the preparation of particle boards is subject to the drawback that the boards exhibit a tendency to adhere to the face of the platens used in their formation. This problem is minimized by incorporating minor amounts of a mixture of certain mono- and di- (saturated or unsaturated aliphatic) acid phosphates or the corresponding pyrophosphates, into the polyisocyanate to be used as binder. The polyisocyanates and the acid phosphates and or pyrophosphates, are applied to the particles separately, or after preblending one with the other. Whether the components are applied separately or in combination one with the other, they can each be applied either neat or in the form of an emulsion or emulsions.
Inventors
- 👤 Alexander McLaughlin
- 👤 Reinhard H. Richter
- 👤 Harold E. Reymore, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:30
CPC Classifications
C; C07; C07F; C07F7/00; C07F7/02; C07F7/08; C07F7/18; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/703; C08G18/705; C08G18/706; C08G18/28; C08G18/30; C08G18/302; C08L; C08L97/00; C08L97/02; C08G2125/00; C08L2205/00; C08L2205/06; C08L75/00; C08L75/04
Claims Analysis
Total Claims: 47
Claim 1
Independent Claim
428 words
In a process for the preparation of particle board wherein particles of organic material capable of being compacted are contacted with a polyisocyanate composition and the treated particles are subsequently formed into boards by the application of heat and pressure, the improvement which comprises contacting said particles, in addition to the treatment with said polyisocyanate composition, with from about 0.1 to about 20 parts, per 100 parts by weight of said polyisocyanate, of a phosphate selected from the class consisting of (a) acid phosphates of the formulae ##STR18## and the ammonium, alkali metal, alkaline earth metal and amine salts thereof; (b) pyrophosphates represented by those derived from the acid phosphates (I) and (II) and mixtures of (I) and (II); (c) The O-monoacyl derivatives of the acid phosphates (I) and (II) having the formulae ##STR19## (d) carbamoyl phosphates having the formula ##STR20## and the ammonium, alkali metal, alkaline earth metal and amine salts of the compounds of formula (VII); (e) branched polyphosphates of the formulae ##STR21## (f) polyphosphates corresponding to the general formula ##STR22## including the cyclometaphosphates (n=3); and (g) mixtures of two or more of said compounds; wherein, in the various formulae shown above, each R is independently selected from the class consisting of alkyl having at least 3 carbon atoms, alkenyl having at least 3 carbon atoms, aryl, aryl substituted by at least one alkyl, alkyl substituted by from 1 to 2 acyloxy groups wherein the acyl group is the residue of an aliphatic monocarboxylic acid having at least 2 carbon atoms, and ##STR23## wherein R' is selected from the class consisting of alkyl, aryl and aryl substituted by at least one alkyl, one of A and B represents hydrogen and the other is selected from the class consisting of hydrogen, methyl, chloromethyl and 2,2,2-trichloroethyl, and m is a number having an average value from 1 to 25; provided that when one of the R's in Formulae (II), (VI), (VIII) an (IX) is alkyl having at least 3 carbon atoms, the other R can also be selected from methyl and ethyl; and further provided that, in Formula (II), the two RX groups taken together with the P atom to which they are attached can additionally form the residue of a heterocyclic nucleus having from 5 to 6 ring atoms; R 1 is hydrocarbyl; R 2 is selected from the class consisting of hydrocarbyl and hydrocarbyl substituted by at least one additional ##STR24## group wherein R has the significance defined above; n is an integer; and X in each instance is a chalcogen selected from oxygen and sulfur.
Claim 2
Dependent Claim
428 words
In a process for the preparation of particle board wherein particles of organic material capable of being compacted are contacted with a polyisocyanate composition and the treated particles are subsequently formed into boards by the application of heat and pressure, the improvement which comprises contacting said particles, in addition to the treatment with said polyisocyanate composition, with from about 0.1 to about 20 parts, per 100 parts by weight of said polyisocyanate, of a phosphate selected from the class consisting of (a) acid phosphates of the formulae ##STR18## and the ammonium, alkali metal, alkaline earth metal and amine salts thereof; (b) pyrophosphates represented by those derived from the acid phosphates (I) and (II) and mixtures of (I) and (II); (c) The O-monoacyl derivatives of the acid phosphates (I) and (II) having the formulae ##STR19## (d) carbamoyl phosphates having the formula ##STR20## and the ammonium, alkali metal, alkaline earth metal and amine salts of the compounds of formula (VII); (e) branched polyphosphates of the formulae ##STR21## (f) polyphosphates corresponding to the general formula ##STR22## including the cyclometaphosphates (n=3); and (g) mixtures of two or more of said compounds; wherein, in the various formulae shown above, each R is independently selected from the class consisting of alkyl having at least 3 carbon atoms, alkenyl having at least 3 carbon atoms, aryl, aryl substituted by at least one alkyl, alkyl substituted by from 1 to 2 acyloxy groups wherein the acyl group is the residue of an aliphatic monocarboxylic acid having at least 2 carbon atoms, and ##STR23## wherein R' is selected from the class consisting of alkyl, aryl and aryl substituted by at least one alkyl, one of A and B represents hydrogen and the other is selected from the class consisting of hydrogen, methyl, chloromethyl and 2,2,2-trichloroethyl, and m is a number having an average value from 1 to 25; provided that when one of the R's in Formulae (II), (VI), (VIII) an (IX) is alkyl having at least 3 carbon atoms, the other R can also be selected from methyl and ethyl; and further provided that, in Formula (II), the two RX groups taken together with the P atom to which they are attached can additionally form the residue of a heterocyclic nucleus having from 5 to 6 ring atoms; R 1 is hydrocarbyl; R 2 is selected from the class consisting of hydrocarbyl and hydrocarbyl substituted by at least one additional ##STR24## group wherein R has the significance defined above; n is an integer; and X in each instance is a chalcogen selected from oxygen and sulfur.
Claim 3
Dependent Claim
42 words
The process of claim 1 wherein said polyisocyanate is a polymethylene polyphenyl polyisocyanate containing from about 25 to about 90 percent by weight of methylenebis (phenyl isocyanate), the remainder of said mixture being oligomeric polymethylene polyphenyl polyisocyanates of functionality greater than 2.
Claim 4
Dependent Claim
24 words
The process of claim 2 wherein the polymethylene polyphenyl polyisocyanate contains from about 35 to about 65 percent by weight of methylenebis (phenyl isocyanate).
Claim 5
Dependent Claim
19 words
The process of claim 1 wherein said phosphate comprises a mixture of lauryl diacid phosphate and dilauryl monoacid phosphate.
Claim 6
Dependent Claim
29 words
The process of claim 1 wherein said phosphate comprises a pyrophosphate derived by removal of water of condensation from a mixture of lauryl diacid phophate and dilauryl monoacid phosphate.
Claim 7
Dependent Claim
19 words
The process of claim 1 wherein said phosphate comprises a mixture of oleyl diacid phosphate and dioleyl monoacid phosphate.
Claim 8
Dependent Claim
29 words
The process of claim 1 wherein said phosphate comprises a pyrophosphate derived by removal of water of condensation from a mixture of oleyl diacid phosphate and dioleyl monoacid phosphate.
Claim 9
Dependent Claim
19 words
The process of claim 1 wherein the particles employed in the preparation of said particle board are wood chips.
Claim 10
Dependent Claim
24 words
The process of claim 1 wherein said polyisocyanate and said phosphate are applied simultaneously to said particles in the form of an aqueous emulsion.
Claim 11
Dependent Claim
16 words
The process of claim 9 wherein said aqueous emulsion of polyisocyanate also comprises an emulsifying agent.
Claim 12
Dependent Claim
17 words
The process of claim 1 wherein said particles are contacted separately with said polyisocyanate and said phosphate.
Claim 13
Dependent Claim
21 words
The process of claim 11 wherein said polyisocyanate and said phosphate are each employed in the form of an aqueous dispersion.
Claim 14
Dependent Claim
22 words
The process of claim 11 wherein said particles are contacted with water prior to being contacted with said polyisocyanate and said phosphate.
Claim 15
Dependent Claim
377 words
In a process for the preparation of particle board wherein particles of cellulosic material are contacted with an aqueous emulsion of a polyisocyanate and the treated particles are subsequently formed into boards by the application of heat and pressure, the improvement which comprises employing an aqueous emulsion containing (a) from about 10 parts by weight to about 99 parts by weight, per 100 parts by weight of emulsion, of a polymethylene polyphenyl polyisocyanate containing from about 25 to about 90 percent by weight of methylenebis (phenyl isocyanate), the remainder of said mixture being oligomeric polymethylene polyphenyl polyisocyanates of functionality greater than 2; and (b) from about 0.1 parts by weight to about 20 parts by weight, per 100 parts by weight of polyisocyanate, of a phosphate selected from the class consisting of (i) acid phosphates of the formulae: ##STR25## and the ammonium, alkali metal, and alkaline earth metal salts thereof, wherein each R is independently selected from the class consisting of alkyl having at least 3 carbon atoms, alkenyl having at least 3 carbon atoms, aryl, aryl substituted by at least one alkyl, alkyl substituted by from 1 to 2 acyloxy groups wherein the acyl group is the residue of an aliphatic monocarboxylic acid having at least 2 carbon atoms, and ##STR26## wherein R' is selected from the class consisting of alkyl, aryl and aryl substituted by at least one alkyl, one of A and B represents hydrogen and the other is selected from the class consisting of hydrogen, methyl, chloromethyl and 2,2,2-trichloroethyl, and m is a number having an average value from 1 to 25; provided that, when one of the R groups in the formula ##STR27## is alkyl having at least 3 carbon atoms, the other R can also be selected from methyl and ethyl and further provided that the two RO groups in said formula, taken together with the P atom to which they are attached, can additionally form the residue of a heterocyclic nucleus having from 5 to 6 ring atoms; (ii) the corresponding pyrophosphates derived from said acid phosphates including mixtures of two or more such phosphates by the removal of water of condensation; and (iii) mixtures of at least one of said acid phosphates and at least one of said pyrophosphates.
Claim 16
Dependent Claim
377 words
In a process for the preparation of particle board wherein particles of cellulosic material are contacted with an aqueous emulsion of a polyisocyanate and the treated particles are subsequently formed into boards by the application of heat and pressure, the improvement which comprises employing an aqueous emulsion containing (a) from about 10 parts by weight to about 99 parts by weight, per 100 parts by weight of emulsion, of a polymethylene polyphenyl polyisocyanate containing from about 25 to about 90 percent by weight of methylenebis (phenyl isocyanate), the remainder of said mixture being oligomeric polymethylene polyphenyl polyisocyanates of functionality greater than 2; and (b) from about 0.1 parts by weight to about 20 parts by weight, per 100 parts by weight of polyisocyanate, of a phosphate selected from the class consisting of (i) acid phosphates of the formulae: ##STR25## and the ammonium, alkali metal, and alkaline earth metal salts thereof, wherein each R is independently selected from the class consisting of alkyl having at least 3 carbon atoms, alkenyl having at least 3 carbon atoms, aryl, aryl substituted by at least one alkyl, alkyl substituted by from 1 to 2 acyloxy groups wherein the acyl group is the residue of an aliphatic monocarboxylic acid having at least 2 carbon atoms, and ##STR26## wherein R' is selected from the class consisting of alkyl, aryl and aryl substituted by at least one alkyl, one of A and B represents hydrogen and the other is selected from the class consisting of hydrogen, methyl, chloromethyl and 2,2,2-trichloroethyl, and m is a number having an average value from 1 to 25; provided that, when one of the R groups in the formula ##STR27## is alkyl having at least 3 carbon atoms, the other R can also be selected from methyl and ethyl and further provided that the two RO groups in said formula, taken together with the P atom to which they are attached, can additionally form the residue of a heterocyclic nucleus having from 5 to 6 ring atoms; (ii) the corresponding pyrophosphates derived from said acid phosphates including mixtures of two or more such phosphates by the removal of water of condensation; and (iii) mixtures of at least one of said acid phosphates and at least one of said pyrophosphates.
Claim 17
Dependent Claim
23 words
The process of claim 14 wherein said polymethylene polyphenyl polyisocyanate contains from about 35 to about 65 percent by weight of methylenebis(phenyl isocyanate).
Claim 18
Dependent Claim
19 words
The process of claim 14 wherein said phosphate comprises a mixture of lauryl diacid phosphate and dilauryl monoacid phosphate.
Claim 19
Dependent Claim
29 words
The process of claim 14 wherein said phosphate comprises a pyrophosphate derived by removal of water of condensation from a mixture of lauryl diacid phosphate and dilauryl monoacid phosphate.
Claim 20
Dependent Claim
19 words
The process of claim 14 wherein said phosphate comprises a mixture of oleyl diacid phosphate and dioleyl monoacid phosphate.
Claim 21
Dependent Claim
29 words
The process of claim 14 wherein said phosphate comprises a pyrophosphate derived by removal of water of condensation from a mixture of oleyl diacid phosphate and dioleyl monoacid phosphate.
Claim 22
Dependent Claim
44 words
The process of claim 14 wherein said phosphate comprises a member selected from the class consisting of butyl diacid phosphate, dibutyl monoacid phosphate, mixtures thereof, and the pyrophosphates derived by removal of water of condensation from said mono- and di-acid phosphates and mixtures thereof.
Claim 23
Dependent Claim
44 words
The process of claim 14 wherein said phosphate comprises a member selected from the class consisting of heptyl diacid phosphate, diheptyl monoacid phosphate, mixtures thereof, and the pyrophosphates derived by removal of water of condensation from said mono- and di-acid phosphates and mixtures thereof.
Claim 24
Dependent Claim
44 words
The process of claim 14 wherein said phosphate comprises a member selected from the class consisting of octyl diacid phosphate, dioctyl monoacid phosphate, mixtures thereof, and the pyrophosphates derived by removal of water of condensation from said mono- and di-acid phosphates and mixtures thereof.
Claim 25
Dependent Claim
73 words
The process of claim 14 wherein said phosphate comprises a self-emulsifying phosphate selected from the class consisting of acid phosphates of the following formulae, mixtures thereof, and the pyrophosphates derived by removal of water of condensation from said acid phosphates and mixtures thereof: ##STR28## wherein R represents ##STR29## where R', A and B have the significance defined in claim 14 and m is a number having an average value from 3 to 30.
Claim 26
Dependent Claim
14 words
The process of claim 14 wherein said aqueous emulsion also comprises an emulsifying agent.
Claim 27
Dependent Claim
13 words
The process of claim 14 wherein said emulsion also comprises a phenol-formaldehyde resin.
Claim 28
Dependent Claim
321 words
In a process for the preparation of particle board wherein particles of cellulosic material are contacted with a polyisocyanate and the treated particles are subsequently formed into boards by the application of heat and pressure, the improvement which comprises contacting said particles, in addition to the treatment with said polyisocyanate, with from about 0.1 to about 20 parts, per 100 parts by weight of said polyisocyanate, of a phosphate selected from the class consisting of: (i) acid phosphates of the formulae: ##STR30## and the ammonium, alkali metal, alkaline earth metal and amine salts thereof, wherein each R is independently selected from the class consisting of alkyl having at least 3 carbon atoms, alkenyl having at least 3 carbon atoms, aryl, aryl substituted by at least one alkyl, alkyl substituted by from 1 to 2 acyloxy groups wherein the acyl group is the residue of an aliphatic monocarboxylic acid having at least 2 carbon atoms, and ##STR31## wherein R' is selected from the class consisting of alkyl, aryl and aryl substituted by at least one alkyl, one of A and B represents hydrogen and the other is selected from the class consisting of hydrogen, methyl, chloromethyl and 2,2,2-trichloromethyl, and m is a number having an average value from 1 to 25; provided that, when one of the R groups of the formula ##STR32## is alkyl having at least 3 carbon atoms, the other R can also be selected from methyl and ethyl, and further provided that the two RO groups in said formula, taken together with the P atom to which they are attached, can additionally form the residue of a heterocyclic nucleus having from 5 to 6 ring atoms; (ii) the corresponding pyrophosphates derived from said acid phosphates including mixtures of two or more such phosphates by the removal of water of condensation; and (iii) mixtures of at least one of said acid phosphates and at least one of said pyrophosphates.
Claim 29
Dependent Claim
321 words
In a process for the preparation of particle board wherein particles of cellulosic material are contacted with a polyisocyanate and the treated particles are subsequently formed into boards by the application of heat and pressure, the improvement which comprises contacting said particles, in addition to the treatment with said polyisocyanate, with from about 0.1 to about 20 parts, per 100 parts by weight of said polyisocyanate, of a phosphate selected from the class consisting of: (i) acid phosphates of the formulae: ##STR30## and the ammonium, alkali metal, alkaline earth metal and amine salts thereof, wherein each R is independently selected from the class consisting of alkyl having at least 3 carbon atoms, alkenyl having at least 3 carbon atoms, aryl, aryl substituted by at least one alkyl, alkyl substituted by from 1 to 2 acyloxy groups wherein the acyl group is the residue of an aliphatic monocarboxylic acid having at least 2 carbon atoms, and ##STR31## wherein R' is selected from the class consisting of alkyl, aryl and aryl substituted by at least one alkyl, one of A and B represents hydrogen and the other is selected from the class consisting of hydrogen, methyl, chloromethyl and 2,2,2-trichloromethyl, and m is a number having an average value from 1 to 25; provided that, when one of the R groups of the formula ##STR32## is alkyl having at least 3 carbon atoms, the other R can also be selected from methyl and ethyl, and further provided that the two RO groups in said formula, taken together with the P atom to which they are attached, can additionally form the residue of a heterocyclic nucleus having from 5 to 6 ring atoms; (ii) the corresponding pyrophosphates derived from said acid phosphates including mixtures of two or more such phosphates by the removal of water of condensation; and (iii) mixtures of at least one of said acid phosphates and at least one of said pyrophosphates.
Claim 30
Dependent Claim
17 words
The process of claim 26 wherein said polyisocyanate and said phosphate are applied sequentially to said particles.
Claim 31
Dependent Claim
25 words
The process of claim 26 wherein said particles are first contacted with water and then with a preformed mixture of said polyisocyanate and said phosphate.
Claim 32
Dependent Claim
15 words
The process of claim 26 wherein said particles are additionally contacted with a phenol-formaldehyde resin.
Claim 33
Dependent Claim
44 words
The process of claim 26 wherein said phosphate comprises a member selected from the class consisting of lauryl diacid phosphate, dilauryl monoacid phosphate, mixtures thereof, and the pyrophosphates derived by removal of water of condensation from said mono- and di-acid phosphates and mixtures thereof.
Claim 34
Dependent Claim
44 words
The process of claim 26 wherein said phosphate comprises a member selected from the class consisting of oleyl diacid phosphate, dioleyl monoacid phosphate, mixtures thereof, and the pyrophosphates derived by removal of water of condensation from said mono- and di-acid phosphates and mixtures thereof.
Claim 35
Dependent Claim
44 words
The process of claim 26 wherein said phosphate comprises a member selected from the class consisting of butyl diacid phosphate, dibutyl monoacid phosphate, mixtures thereof, and the pyrophosphates derived by removal of water of condensation from said mono- and di-acid phosphates and mixtures thereof.
Claim 36
Dependent Claim
44 words
The process of claim 26 wherein said phosphate comprises a member selected from the class consisting of heptyl diacid phosphate, diheptyl monoacid phosphate, mixtures thereof, and the pyrophosphates derived by removal of water of condensation from said mono- and di-acid phosphates and mixtures thereof.
Claim 37
Dependent Claim
44 words
The process of claim 26 wherein said phosphate comprises a member selected from the class consisting of octyl diacid phosphate, dioctyl monoacid phosphate, mixtures thereof, and the pyrophosphates derived by removal of water of condensation from said mono- and di-acid phosphates and mixtures thereof.
Claim 38
Dependent Claim
73 words
The process of claim 26 wherein said phosphate comprises a self-emulsifying phosphate selected from the class consisting of acid phosphates of the following formulae, mixtures thereof, and the pyrophosphates derived by removal of water of condensation from said acid phosphates and mixtures thereof: ##STR33## wherein R represents ##STR34## where R', A and B have the significance defined in claim 26 and m is a number having an average value from 3 to 30.
Claim 39
Dependent Claim
18 words
The process of claim 35 wherein said self-emulsifying phosphate is employed in the form of an aqueous emulsion.
Claim 40
Dependent Claim
283 words
A storage stable composition comprising a mixture of: (a) a polymethylene polyphenol polyisocyanate containing from about 25 to about 90 percent by weight of methylenebis(phenyl isocyanate) the remainder of said mixture being oligomeric polymethylene polyphenol polyisocyanates having a functionality higher than 2.0; and (b) from about 0.1 parts by weight to about 20 parts by weight, per 100 parts by weight of said polyisocyanate, of a pyrophosphate derived by removal of water of condensation from at least one acid phosphate selected from acid phosphates of the formulae: ##STR35## wherein each R is independently selected from the class consisting of alkyl having at least 3 carbon atoms, alkeyl having at least 3 carbon atoms, aryl, aryl substituted by at least one alkyl, alkyl substituted by from 1 to 2 acyloxy groups wherein the acyl group is the residue of an aliphatic monocarboxylic acid having at least 2 carbon atoms, and ##STR36## wherein R' is selected from the class consisting of alkyl, aryl and aryl substituted by at least one alkyl, one of A and B represents hydrogen and the other is selected from the class consisting of hydrogen, methyl, chloromethyl and 2,2,2-trichloroethyl, and m is a number having an average value from 1 to 25, and mixtures of two or more of said acid phosphates; provided that, when one of the R groups in the formula ##STR37## is alkyl having at least 3 carbon atoms, the other R can also be selected from methyl and ethyl, and further provided that the two RO groups in said formula, taken together with the P atom to which they are attached, can additionally form the residue of a heterocyclic nucleus having from 5 to 6 ring atoms.
Claim 41
Dependent Claim
283 words
A storage stable composition comprising a mixture of: (a) a polymethylene polyphenol polyisocyanate containing from about 25 to about 90 percent by weight of methylenebis(phenyl isocyanate) the remainder of said mixture being oligomeric polymethylene polyphenol polyisocyanates having a functionality higher than 2.0; and (b) from about 0.1 parts by weight to about 20 parts by weight, per 100 parts by weight of said polyisocyanate, of a pyrophosphate derived by removal of water of condensation from at least one acid phosphate selected from acid phosphates of the formulae: ##STR35## wherein each R is independently selected from the class consisting of alkyl having at least 3 carbon atoms, alkeyl having at least 3 carbon atoms, aryl, aryl substituted by at least one alkyl, alkyl substituted by from 1 to 2 acyloxy groups wherein the acyl group is the residue of an aliphatic monocarboxylic acid having at least 2 carbon atoms, and ##STR36## wherein R' is selected from the class consisting of alkyl, aryl and aryl substituted by at least one alkyl, one of A and B represents hydrogen and the other is selected from the class consisting of hydrogen, methyl, chloromethyl and 2,2,2-trichloroethyl, and m is a number having an average value from 1 to 25, and mixtures of two or more of said acid phosphates; provided that, when one of the R groups in the formula ##STR37## is alkyl having at least 3 carbon atoms, the other R can also be selected from methyl and ethyl, and further provided that the two RO groups in said formula, taken together with the P atom to which they are attached, can additionally form the residue of a heterocyclic nucleus having from 5 to 6 ring atoms.
Claim 42
Dependent Claim
22 words
A composition according to claim 37 wherein the pyrophosphate is derived from a mixture of lauryl diacid phosphate and dilauryl monoacid phosphate.
Claim 43
Dependent Claim
22 words
A composition according to claim 37 wherein the pyrophosphate is derived from a mixture of oleyl diacid phosphate and dioleyl monoacid phosphate.
Claim 44
Dependent Claim
22 words
A composition according to claim 37 wherein the pyrophosphate is derived from a mixture of butyl diacid phosphate and dibutyl acid phosphate.
Claim 45
Dependent Claim
22 words
A composition according to claim 37 wherein the pyrophosphate is derived from a mixture of heptyl diacid phosphate and diheptyl acid phosphate.
Claim 46
Dependent Claim
22 words
A composition according to claim 37 wherein the pyrophosphate is derived from a mixture of octyl diacid phosphate and dioctyl acid phosphate.
Claim 47
Dependent Claim
12 words
A composition according to claim 37 which also comprises an emulsifying agent.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-23 | 1984-09-22 | 1985-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-23 | 1988-09-22 | 1989-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-23 | 1992-09-22 | 1993-03-24 | $7700.00 | Window Closed / Lapsed |