US4137049A — Device for use as an elapsed time indicator or ti…

Claim 1

Independent Claim 180 words

A device for indicating the elapse of time comprising: a container, a vapor generating means enclosed in said container, said vapor generating means including a first chemical having a vapor pressure, a carrier enclosed in said container, a mixture including a second chemical, an indicator, and a gel forming agent impregnated in said carrier; the longitudinal outer surface of said mixture being in contact with a portion of the longitudinal inner surface of said container, said second chemical having a pH value different from said first chemical, said indicator responsive to a change in PH value due to the reaction of said first and second chemicals; the viscosity of said mixture impregnated in said carrier being of such a value so as to provide that said second chemical and said indicator are substantially uniformly held in a dispersion in said carrier and further to provide an impedance to the movement of the vapor through said carrier, whereby substantially accurate indication of the elapse of a predetermined time after activation of said vapor generating means is indicated for certain temperature ranges.

Claim 2

Independent Claim 180 words

A device for indicating the elapse of time comprising: a container, a vapor generating means enclosed in said container, said vapor generating means including a first chemical having a vapor pressure, a carrier enclosed in said container, a mixture including a second chemical, an indicator, and a gel forming agent impregnated in said carrier; the longitudinal outer surface of said mixture being in contact with a portion of the longitudinal inner surface of said container, said second chemical having a pH value different from said first chemical, said indicator responsive to a change in PH value due to the reaction of said first and second chemicals; the viscosity of said mixture impregnated in said carrier being of such a value so as to provide that said second chemical and said indicator are substantially uniformly held in a dispersion in said carrier and further to provide an impedance to the movement of the vapor through said carrier, whereby substantially accurate indication of the elapse of a predetermined time after activation of said vapor generating means is indicated for certain temperature ranges.

Claim 3

Dependent Claim 32 words

A device as set forth in claim 1 wherein said mixture forms a gel after impregnation into said carrier, said gel having a viscosity between 10 and 380 centipoise at 25° C.

Claim 4

Dependent Claim 25 words

A device as set forth in claim 1 wherein the vapor pressure of said first chemical is between 0.1 and 10 atmospheres at 25° C.

Claim 5

Dependent Claim 28 words

A device as set forth in claim 1 further including indicia means, said indicia means being attached to said container for indicating the passage of certain time intervals.

Claim 6

Dependent Claim 24 words

A device as set forth in claim 1 wherein said first chemical is a basic material, and said second chemical is an acidic material.

Claim 7

Dependent Claim 18 words

A device as set forth in claim 1, wherein said mixture includes 50% to 99% water by weight.

Claim 8

Dependent Claim 23 words

A device as set forth in claim 1 wherein said gel-forming agent is taken from the group consisting of polysaccharid and an agar.

Claim 9

Dependent Claim 34 words

A device as set forth in claim 1 wherein said carrier is a porous polymer having void volume in the range from 10% to 50% and void size of between 5 to 100 microns.

Claim 10

Dependent Claim 14 words

A device as set forth in claim 1 wherein said indicator is phenol red.

Claim 11

Dependent Claim 15 words

A device as set forth in claim 1 wherein said carrier is a porous material.

Claim 12

Dependent Claim 19 words

A device as set forth in claim 10 wherein said carrier is in the shape of a cylindrical plug.

Claim 13

Dependent Claim 16 words

A device as set forth in claim 1 wherein said container is substantially impermeable to moisture.

Claim 14

Dependent Claim 16 words

A device as set forth in claim 12 wherein said container is coated with polyvinylidene chloride.

Claim 15

Dependent Claim 24 words

A device as set forth in claim 1 wherein said first chemical is an acidic material and said second chemical is a basic material.

Claim 16

Dependent Claim 24 words

A device as set forth in claim 14 wherein said first chemical is an ammonia-releasing compound and said second chemical is a weak acid.

Claim 17

Dependent Claim 22 words

A device as set forth in claim 15 wherein said first chemical is ammonium hydroxide and said second chemical is citric acid.

Claim 18

Independent Claim 118 words

A device for use as a time indicator or time temperature indicator comprising: a container, a vapor generating means including a first chemical received in said container, a porous material being impregnated with a mixture including a second chemical, a pH sensitive indicator, and a gel forming agent, said gel forming agent uniformly holding said second chemical and said pH sensitive indicator in said porous material and for providing an impedance to the flow of the vapor through said porous material; said mixture having a viscosity greater than 10 centipose at twenty five degrees centigrade; said porous material being located inside said container; the vapor of said first chemical having a pH value different from said second chemical.

Claim 19

Independent Claim 118 words

A device for use as a time indicator or time temperature indicator comprising: a container, a vapor generating means including a first chemical received in said container, a porous material being impregnated with a mixture including a second chemical, a pH sensitive indicator, and a gel forming agent, said gel forming agent uniformly holding said second chemical and said pH sensitive indicator in said porous material and for providing an impedance to the flow of the vapor through said porous material; said mixture having a viscosity greater than 10 centipose at twenty five degrees centigrade; said porous material being located inside said container; the vapor of said first chemical having a pH value different from said second chemical.

Claim 20

Dependent Claim 21 words

A device as set forth in claim 17 wherein the time indicator temperature range is from 16° C. to 27° C.

Claim 21

Dependent Claim 128 words

A time indicating device comprising: a substantially moisture impermeable tube; a frangible ampule contained in said tube; said frangible ampule containing an ammonia vapor releasing compound, a porous polymer plug contained in said tube and being impregnated with a mixture of a weak acid, a pH change indicator, a gel forming agent and water; said gel forming agent uniformly holding said weak acid and said pH change indicator in said porous polymer plug and providing an impedance to the flow of ammonia vapor through said porous polymer plug; indicia means in register with said plug for indicating time information; whereby, upon the fracture of said frangible ampule, an indicator front moves up said plug approximately in proportion to the time interval which is shown on said indicia means.

Claim 22

Dependent Claim 128 words

A time indicating device comprising: a substantially moisture impermeable tube; a frangible ampule contained in said tube; said frangible ampule containing an ammonia vapor releasing compound, a porous polymer plug contained in said tube and being impregnated with a mixture of a weak acid, a pH change indicator, a gel forming agent and water; said gel forming agent uniformly holding said weak acid and said pH change indicator in said porous polymer plug and providing an impedance to the flow of ammonia vapor through said porous polymer plug; indicia means in register with said plug for indicating time information; whereby, upon the fracture of said frangible ampule, an indicator front moves up said plug approximately in proportion to the time interval which is shown on said indicia means.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1982-01-29	1982-07-31	1983-01-30	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1986-01-29	1986-07-31	1987-01-30	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1990-01-29	1990-07-31	1991-01-30	$7700.00	Window Closed / Lapsed

Device for use as an elapsed time indicator or time temperature indicator

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