U.S. patent application number 13/484487 was filed with the patent office on 2012-09-20 for device and a process for mass monitoring of radiation exposure.
Invention is credited to Gordhanbhai N. Patel.
Application Number | 20120235062 13/484487 |
Document ID | / |
Family ID | 46613463 |
Filed Date | 2012-09-20 |
United States Patent
Application |
20120235062 |
Kind Code |
A1 |
Patel; Gordhanbhai N. |
September 20, 2012 |
DEVICE AND A PROCESS FOR MASS MONITORING OF RADIATION EXPOSURE
Abstract
A radiation detection device with at least one self indicating
radiation sensor and at least one machine readable sensor.
Inventors: |
Patel; Gordhanbhai N.;
(Middlesex, NJ) |
Family ID: |
46613463 |
Appl. No.: |
13/484487 |
Filed: |
May 31, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12248248 |
Oct 9, 2008 |
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13484487 |
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60998638 |
Oct 12, 2007 |
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Current U.S.
Class: |
250/474.1 ;
250/472.1; 250/483.1; 250/484.3; 250/484.5 |
Current CPC
Class: |
G01T 1/04 20130101 |
Class at
Publication: |
250/474.1 ;
250/472.1; 250/484.3; 250/484.5; 250/483.1 |
International
Class: |
G01T 1/02 20060101
G01T001/02; G01T 1/10 20060101 G01T001/10; G01T 1/06 20060101
G01T001/06; G01T 1/11 20060101 G01T001/11 |
Claims
1-23. (canceled)
24. A radiation detection device comprising at least one self
indicating radiation sensor and at least one accredited sensor.
25. The radiation detection device of claim 24 wherein at least one
of said self indicating radiation sensor and said accredited sensor
is contained in an element selected from a license, an
identification card, and an access card.
26. The radiation detection device of claim 25 further comprising
an RFID.
27. The radiation detection device of claim 24 further comprising
an RFID.
28. The radiation detection device of claim 24 wherein at least one
of said self indicating radiation sensor and said accredited sensor
is contained in an element selected from credit card, driver's
license, passport, social security card, national ID cards,
employee ID card, school ID card, key/control access cards, VIP
cards, membership cards, IC/smart cards, key tags, luggage tags and
bank/ATM cards.
29. The radiation detection device of claim 24 further comprising
text on said device.
30. The radiation detection device of claim 29 wherein said text
identifies a user of said device.
31. The radiation detection device of claim 24 wherein said
accredited sensor is selected from TLD, OSL, RLG and X-ray
film.
32. The radiation detection device of claim 24 where a core layer
is sandwiched between a transparent layer and an opaque layer.
33. The radiation detection device of claim 32 wherein said
transparent layer is a colored transparent optical filter.
34. The radiation detection device of claim 32 where said core
layer has at least one cavity therein.
35. The radiation detection device of claim 34 where said self
indicating radiation sensor is in said cavity.
36. The radiation detection device of claim 34 where said
accredited sensor is in said cavity.
37. The radiation detection device of claim 24 where at least one
of said self indicating radiation sensor or said accredited sensor
is protected from ambient conditions.
38. The radiation detection device of claim 24 further comprising a
window through which at least one of said self indicating radiation
sensor and said accredited sensor is read.
39. The radiation detection device of claim 38 wherein said window
is a removable layer or a liftable layer.
40. The radiation detection device of claim 24 further comprising
an indicator for monitoring false signals.
41. The radiation detection device of claim 24 further comprising
at least one indicator selected from the group consisting of an
indicator for monitoring tampering, an indicator for monitoring
false negative, an indicator for monitoring archiving of the
exposure, an indicator for monitoring shelf life, an indicator for
monitoring UV exposure and an indicator for monitoring
temperature.
42. The radiation detection device of claim 24 wherein at least one
of said self indicating radiation sensor and said accredited sensor
is sandwiched between two layers.
43. The radiation detection device of claim 24 comprising at least
one transparent layer.
44. The radiation detection device of claim 24 comprising at least
one opaque layer.
45. The radiation detection device of claim 24 comprising at least
one layer selected from a non-stick layer and a non-contaminating
layer.
46. The radiation detection device of claim 24 wherein at least one
of said self indicating radiation sensor and said accredited sensor
is encapsulated with a material selected from a non-stick material
and a non-contaminating material.
47. The radiation detection device of claim 46 where at least one
of said non-stick material and said non-contaminating material
comprises a material selected from Teflon.RTM. and silicone.
48. The radiation detection device of claim 24 wherein said device
has a thickness of 0.1 to 5 mm.
49. The radiation detection device of claim 48 wherein said device
has a thickness of 0.9 to 1.1 mm.
50. The radiation detection device of claim 24 wherein said device
has a face with a surface area of at least about 1 mm to no more
than about 1 meter.
51. The radiation detection device of claim 24 wherein said device
is a rectangle with sides of about 2 mm to about 200 mm.
52. The radiation detection device of claim 24 wherein is a
rectangle with a long side of about 7 cm to about 10 cm and a short
side of about 4 cm to about 6 cm.
53. The radiation detection device of claim 24 wherein said self
indicating radiation sensor has a sensitivity of 0.01 rad.
54. The radiation detection device of claim 24 said self indicating
radiation sensor comprises a diacetylene.
55. The radiation detection device of claim 24 attached to an
object.
56. The radiation detection device of claim 55 wherein said object
is a human.
57-78. (canceled)
79. A radiation detection device comprising at least one radiation
sensor and at least one accredited sensor.
80. The radiation detection device of claim 79 wherein said
radiation sensor is a self indicating radiation sensor.
81. The radiation detection device of claim 79 wherein at least one
of said radiation sensor and said accredited sensor is contained in
an element selected from a license, an identification card, and an
access card.
82. The radiation detection device of claim 79 wherein at least one
of said self indicating radiation sensor and said accredited sensor
is contained in an element selected from credit card, driver's
license, passport, social security card, national ID cards,
employee ID card, school ID card, key/control access cards, VIP
cards, membership cards, IC/smart cards, key tags, luggage tags and
bank/ATM cards.
83. The radiation detection device of claim 79 where a core layer
is sandwiched between a transparent, colored transparent optical
filter and an opaque layer.
84. The radiation detection device of claim 83 where said core
layer has at least one cavity therein.
85. The radiation detection device of claim 84 where said radiation
sensor is in said cavity.
86. The radiation detection device of claim 84 where said
accredited sensor is in said cavity.
87. The radiation detection device of claim 79 where at least one
of said radiation sensor or said machine readable sensor is
protected from ambient conditions.
88. The radiation detection device of claim 79 further comprising a
window through which at least one of said radiation sensor and said
accredited sensor is read.
89. The radiation detection device of claim 88 wherein said window
is a removable layer or a liftable layer.
90. The radiation detection device of claim 79 further comprising
an indicator for monitoring false signals.
91. The radiation detection device of claim 79 further comprising
at least one indicator selected from the group consisting of an
indicator for monitoring tampering, an indicator for monitoring
false negative, an indicator for monitoring archiving of the
exposure, an indicator for monitoring shelf life and an indicator
for monitoring temperature.
92. The radiation detection device of claim 79 wherein at least one
of said radiation sensor and said accredited sensor is sandwiched
between two layers.
93. The radiation detection device of claim 92 where at least one
layer of said layers is transparent.
94. The radiation detection device of claim 92 where one layer of
said layers is opaque.
95. The radiation detection device of claim 92 wherein at least one
layer of said two layers is selected from a non-stick layer and a
non-contaminating layer.
96. The radiation detection device of claim 79 wherein at least one
of said radiation sensor and said accredited sensor is encapsulated
with a material selected from a non-stick material and a
non-contaminating material.
97. The radiation detection device of claim 96 where at least one
of said non-stick material and said non-contaminating material
comprises a material selected from Teflon.RTM. and silicone.
98. The radiation detection device of claim 79 wherein said device
has a thickness of 0.1 to 5 mm.
99. The radiation detection device of claim 98 wherein said device
has a thickness of 0.9 to 1.1 mm.
100. The radiation detection device of claim 79 wherein said device
has a face with a surface area of at least about 1 mm to no more
than about 1 meter.
101. The radiation detection device of claim 79 wherein is a
rectangle with sides of about 2 mm to about 200 mm.
102. The radiation detection device of claim 79 wherein is a
rectangle with a long side of about 7 cm to about 10 cm and a short
side of about 4 cm to about 6 cm.
103. The radiation detection device of claim 79 wherein said
radiation sensor has a sensitivity of 0.01 rad.
104. The radiation detection device of claim 79 said radiation
sensor comprises a diacetylene.
105. The radiation detection device of claim 79 attached to an
object.
106. The radiation detection device of claim 105 wherein said
object is a human.
107. An identification device comprising at least one machine
readable radiation sensor.
108. The identification device of claim 107 wherein said machine
readable sensor is a self reading sensor.
109. The identification device of claim 107 wherein said machine
readable sensor is an accredited sensor.
110. The identification device of claim 107 wherein said machine
readable sensor is both a self reading sensor and an accredited
sensor.
111. The identification device of claim 107 further comprising a
for remote sensing device.
112. The identification device of claim 111 wherein remote sensing
device is an RFID.
113. The identification device of claim 107 wherein said
identification device is in the form of a license, identification
or access card.
114. The radiation detection device of claim 107 wherein at least
one of said self indicating radiation sensor and said accredited
sensor is contained in an element selected from credit card,
driver's license, passport, social security card, national ID
cards, employee ID card, school ID card, key/control access cards,
VIP cards, membership cards, IC/smart cards, key tags, luggage tags
and bank/ATM cards.
115. The radiation detection device of claim 107 further comprising
text on said device.
116. The radiation detection device of claim 115 wherein said text
identifies a user of said device.
117. The radiation detection device of claim 107 wherein said
accredited sensor is selected from TLD, OSL, RLG and X-ray
film.
118. The radiation detection device of claim 24 wherein said
accredited sensor is selected from OSL, RLG, ESR and NMR.
119. The radiation detection device of claim 118 wherein said self
indicating radiation sensor, said OSL, said RLG, said ESR of said
NMR can be read without removal.
120. The radiation detection device of claim 79 wherein said
accredited sensor is selected from OSL, RLG, ESR and NMR.
121. The radiation detection device of claim 120 wherein said
radiation sensor, said OSL, said RLG, said ESR of said NMR can be
read without removal.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to pending Provisional
Patent Appl. No. 60/998,638 filed Oct. 12, 2007.
FIELD OF THE INVENTION
[0002] This invention relates to a device, preferably in the form
of a identification device (ID), containing a radiation sensor for
monitoring radiation exposure of the general public and processes
of reading dose and determining dose distribution of the area in
the event of radiological incident.
BACKGROUND OF THE INVENTION
[0003] Radiation is known to cause cancer. On average, we receive
about 0.3 rads/year of high energy radiation. Rad (radiation
absorbed dose, 1 rad=10 mSv) is one of the units of radiation
exposure. According to the US Nuclear Regulatory Commission (NRC)
guidelines, the maximum permitted dose for an occupational
radiation worker is 5 rads/year, not to exceed 25 rads for the
life. There is no easily detectable clinical effect in humans up to
25 rads. However, on average, if 2,500 people are exposed to one
rad of radiation, one is expected to die of radiation induced
cancer. Hence, we need to minimize the exposure and should monitor
radiation exposure from very low dose, e.g., 10 millirads to lethal
dose, e.g., a few thousand rads.
[0004] A large number of radiation detectors, monitors, and
dosimeters are used for detecting and monitoring radiation. The
most popular detectors include ionization chambers, proportional
counters, Geiger-Mueller counters, scintillation detectors,
semiconductor diode detectors (also referred herein as electronic
sensor or electronic detector), and dosimeters such as
Thermoluminescence Dosimeters (TLD), Optically Simulated
Luminescence (OSL), RadioLuminescence Glass (RLG), X-ray film, and
track etch. Track-etch type dosimeters are usually used for
monitoring high Linear Energy Transfer (LET) particles, such as
alpha particles and neutrons. Many other radiation dosimeters
comprising a material which changes color or which change in other
physical and chemical properties are reported in literature.
Individually, or collectively, these devices for monitoring
radiation are referred to as dosimeter(s).
[0005] X-ray film, TLD, RLG, and OSL are widely used for monitoring
personal exposure to radiation. They are highly sensitive (e.g.,
monitor very low dose, e.g., 1 millirad) and can monitor radiation
over a very wide dose range, e.g., from 1 millirad to over 10,000
rads. They are also very accurate (e.g., accuracy of about 5%).
Companies offering services to monitor radiation using these
dosimeters/sensors normally require their facilities, sensors,
dosimeters and processes for monitoring radiation validated by a an
organization, often a government agency (such as NAVLAP (National
Voluntary Laboratory Accreditation) in the USA, a non-profit or an
independent organization. X-ray film, TLD, RLG, OSL and alike
sensors and dosimeters are referred herein as accredited or
validated sensors and/or accredited dosimeters and the methods used
as for determination of the dose as accredited or validated methods
or processes. However, they are not instant and self-reading. They
need to be sent to a laboratory for determination of the dose,
which may take several days.
[0006] A number of patents have been issued on film, TLD, RLG, and
OSL type radiation dosimeters.
[0007] Luminescence techniques in radiation dosimetry have
traditionally been dominated by thermal methods in which a sample,
such as a ThermoLuminescence Dosimeter or TLD, is exposed to
radiation and then heated in the dark. At a certain temperature, or
within a certain temperature range, luminescence (light) is emitted
from the material. The intensity is related, by calibration
procedures, to the original absorbed dose of radiation.
[0008] However, in many circumstances, optically stimulated
luminescence (OSL) has proven to be a superior method of measuring
radiation dose. Generally speaking, OSL methods illuminate a
previously irradiated dosimeter with light of a particular
frequency and intensity. This exposure excites light production
within the dosimeter by transfer of charges from traps to
luminescence centers. Then, by measuring the intensity and duration
of the resulting luminescence signal that is emitted from the
dosimeter, an accurate measure of the amount of radiation to which
the dosimeter was exposed can be obtained. Methods and dosimeters
employing optically stimulated luminescence in the detection of
radiation exposures in various configurations are described in U.S.
Pat. Nos. 5,030,834; 5,091,653; 5,567,948; 5,569,927; 5,732,590;
5,811,822; 5,892,234; 5,962,857; 6,087,666, 6,316,782; and
6,414,324.
[0009] Previously, glass has been considered as potential TLD and
OSL phosphors since it was recognized that the optical transparency
of it offers the advantage of more efficient light collection. For
example, U.S. Pat. No. 5,656,815 to Huston et al. reports the use
of glass as a dosimeter. U.S. Pat. No. 5,811,822 to Huston et al.
describes novel glass phosphor materials that exhibit highly
favorable characteristics for OSL dosimetry applications.
Radiophotoluminescent glass (RLG) dosimetry uses a silver activated
meta-phosphate glass sheet. Irradiated plates are imaged with a CCD
camera as a UV light depopulates the photostimulable phosphor traps
emitting visible light. Other dosimeters include: alanine/Electron
Proton Resonance (EPR) dosimetry, Nuclear Magnetic Resonance (NMR)
technique for measurement of dose in case of ferrous iron dosimeter
and a change in conductivity.
[0010] Color changing/developing Self-indicating Instant Radiation
Alert Dosimeters (SIRAD) for monitoring low dose, e.g., 0.1 to
1,000 rads, have been reported in U.S. Pat. Nos. 5,420,000,
7,727,158 and PCT applications WO2004017095 and PCT/US2004005860
each of which is incorporated by reference. These documents
describe detectors which are commercially available from JP
Laboratories Inc., Middlesex, N.J. under trademark of
SIRAD.RTM..
[0011] Materials used in the sensing strip of SIRAD are a unique
class of compounds called diacetylenes with a general formula
R'--C.ident.C--C.ident.C--R'', wherein R' and R'' are substituent
groups. Diacetylenes are colorless solid monomers. They usually
form red or blue-colored polymers/plastics with a general formula
[.dbd.(R')C--C.ident.C--C(R'').dbd.].sub.n, when irradiated with
high energy radiation, such as X-ray, gamma ray, electrons, and
neutrons. As exposure to radiation increases, the color of the
sensing strip comprising diacetylenes intensifies proportional to
the dose.
[0012] U.S. Pat. No. 7,727,158 to Patel at el discloses a SIRAD
sensor in the form of a label or sticker which is applied on a
detector or dosimeter. A drawback of this device is that it is not
tamper resistant; the SIRAD sticker can be peeled off. The
conventional or accredited TLD, OSL, RLG, and X-ray film dosimeters
are specially designed for occupational radiation workers and hence
are expensive and need to be returned, whether a SIRAD
sticker/label is applied or not. Credit card sized TLD dosimeters,
commonly known as wallet cards or dosimeters, are less expensive
which can be used by non-occupation workers. The chips are
typically loose in plastic cards, the cards are very thick and not
carried by everybody routinely like a credit card. Additionally,
the TLD chips are typically not encapsulated and sealed in the
wallet cards. An improved composite, one piece, less expensive,
tamper resistant, multi sensor dosimeter, at least one of the
sensors being a color developing, such as SIRAD to warn the user of
exposure to high dose, usually non-occupational workers, of
radiation exposure and the other sensor being the conventional
sensor, including electronic devices such as semiconductors, TLD,
OSL, RLG, or X-ray film is described by Patel in U.S. patent
application Ser. No. 12/294,148 entitled "A Self Indicating
Multi-sensor Radiation Dosimeter". These devices are bulky and not
suitable for individual use. This type of dosimeter(s) having more
than one sensor are described herein as multi-sensor dosimeter(s),
multi-sensor device, SIRAD multi-sensor(s), or SIRAD-multi-sensor
dosimeter(s). Self-indicating, color changing or color developing
dosimeters and sensors are referred herein to as self-indicating
radiation sensor, SIRAD sensor(s) or SIRAD dosimeter(s) or simply
SIRAD. The TLD, OSL, RLG, X-ray, track-etch, electronic type
dosimeters or sensors, including doped glass/ceramic and polymeric
are individually or collectively referred to as accurate,
precision, readable, accredited or simply as the other, second or
conventional dosimeter(s) or sensor(s).
[0013] Most of the users, including the radiation occupational
workers, of radiation dosimeters receive no more than the
background dose or a dose which is negligibly higher than the
background dose. However, they do not see or determine their
exposure. They return the dosimeter to a service provider for
determination of the exposure on some predetermined schedule
regardless of possible radiation exposures between test dates.
Critical time is lost between the actual exposure and the detection
therefore the ability to mitigate the exposure is severely
hindered. Furthermore, every badge would need to be read which
leads to inherent waste and excessive cost. Hence, there is a need
for a disposal dosimeter which can determine when, and if, the user
should return the dosimeter earlier for accurate reading by
validated or accredited methods.
[0014] In the case of a detonation of a dirty bomb by terrorists, a
nuclear bomb, or a major accident at a nuclear power plant, first
responders, medical personnel, and the general public need to know,
"Did I receive an acceptable low or a lethal dose of ionizing
radiation?" Hence there is need to know the dose instantly and with
high accuracy. In the event of a radiological incident, affected
people would panic and be worried throughout their lives about the
exposure to radiation. The panic and stampede can cause injuries
and deaths. It is very difficult to measure low dose in humans. One
can estimate dose by analyzing blood if the dose is higher than
about 25 rads. There is also a possibility of lawsuits. In order to
minimize the panic and worry, there is a strong need to provide a
dosimeter in a form which most of us carry almost all the time.
However, this is not practical with the typical conventional
dosimeters.
[0015] In an event of a radiological incident, the dosimeters
preferably are to be read at a very high speed e.g., from a hundred
to thousands a minute. Hence, there is also a need for a machine
readable dosimeter which can be read at a very high speed.
Disclosed herein is an Identification Personal Dosimeter (IDPD)
which identifies to an individual, his/her approximate exposure to
radiation immediately and which has a sensor which can be
accurately read by a machine at a very high speed if warranted.
SUMMARY OF THE INVENTION
[0016] If everybody has an IDPD, it is possible to measure the
radiation exposure of most of the people in an event of a
radiological incident. If an IDPD has a visual sensor such as that
of SIRAD, it will provide its user with a preliminary indication of
radiation exposure just by looking at the SIRAD sensor and if there
is no color development at the end of the shelf life or use period,
the dosimeter can be disposed off and the expenses of reading the
accurate dose by accredited methods can be eliminated. Since the
driver's licenses, credit cards, and employee ID cards are replaced
with new ones every year or few years the incorporation of a
radiation detector into a commodity greatly expedites its use and
insures that an early detection of radiation is in place.
[0017] It is an objective of the present invention is to provide an
IDPD which is simple, inexpensive, disposable, practically
non-destructible, lightweight, tamper resistant, machine readable
and wherein exposure is readily evident.
[0018] It is another object of the present invention to provide an
IDPD which does not require external power, such as a battery,
integrates the dose from 0.01 to 10,000 rads for about one year at
a high speed, preferably has information identifying the individual
carrying the device and further has a machine readable
detector.
[0019] It is another objective of the invention to incorporate a
radiation sensor in a widely used format such as license,
identification card or access card particularly selected from
credit card, driver's license, passport, social security card,
national ID cards, employee ID card, school ID card, key/control
access cards, VIP cards, membership cards, IC/smart cards, key
tags, luggage tags and bank/ATM cards including those with
RFID.
[0020] Yet another objective of the present invention is to seal,
coat, encapsulate, or cover the sensor with a material or layer to
prevent it from being contaminated during making or using, and to
protect it from undesirable effects such as humidity and light.
[0021] Another objective of the invention is to have a window to
read the sensor. The window could be transparent or may have a
removable or liftable layer.
[0022] Yet another objective of the invention is provide a devise
and the ability to read the sensor with a reader such as a CCD
camera, electron spin resonance (ESR), nuclear magnetic resonance
(NMR), spectroscopy such as fluorescence, visual, ultra violet
(UV), infra red (IR), and/or scanning and imaging without removing
it from the IDPD.
[0023] Yet another objective of the invention is to have the IDPD
devices contain personal identification information stored as a
barcode, a magnetic strips, an electronic chip or the like.
[0024] Yet another objective of the present invention is to provide
remotely readable dose and/or personal information, including RFID
devices. The device optionally may have a small power source, such
as a flat plastic battery, if so required.
[0025] Yet another objective of the present invention is to provide
a disposable dosimeter which allows the user to estimate the dose
instantly and then determine the dose accurately, if required, with
conventional, accredited sensors and methods.
[0026] Yet another objective of the present invention is to provide
a removable layer which is opaque to UV and sunlight on at least
one sensor.
[0027] These and other advantages, as would be realized, are
provided in a radiation detection device with at least one self
indicating radiation sensor and at least one accredited sensor.
[0028] Yet another embodiment is provided in a process for
determining exposure to radiation by an individual. The process
includes providing a radiation detection device to the individual
wherein the radiation detection device comprises at least one self
indicating radiation sensor and/or at least one accredited sensor.
A calibration method is provided wherein the individual can
determine exposure to radiation above a threshold radiation by
observing the self indicating radiation sensor. A method is
provided for the individual to report an observation of radiation
exposure above the threshold radiation. If there is an observation
of radiation exposure the accurate radiation dosage is measured by
reading the accredited sensor. The individual is then treated in
accordance with the accurate radiation dosage measured.
[0029] Yet another embodiment is provided in a process of making a
radiation detection device. In the process at least one self
indicating radiation sensor and/or at least one accredited sensor
and a matrix is provided. The self indicating radiation sensor and
said accredited sensor are embedded in the matrix.
[0030] Yet another embodiment is provided in a process of
determining exposure to radiation. The process includes providing a
radiation detection device with at least one self indicating
radiation sensor and/or at least one accredited sensor to at least
one individual; visual inspection of the self indicating radiation
sensor by the individual wherein a change of color indicates a
potential exposure; reporting the potential exposure; machine
reading the machine readable sensor to determine if an exposure to
an actual dose above a threshold amount has occurred; and
mitigating a source of the actual dose.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is a schematic cross sectional representation of an
IDPD of the present invention.
[0032] FIG. 2 is a schematic cross sectional representation of an
IDPD with an encapsulated sensor.
[0033] FIG. 3 is a schematic cross sectional representation of a
three-layered IDPD with a sensor in a cavity.
[0034] FIG. 4 is a schematic cross sectional representation of a
three-layered IDPD with adhesive layers and a sensor in a
cavity.
[0035] FIG. 5 is a schematic cross sectional representation of an
IDPD with two sensors.
[0036] FIG. 6 is a schematic cross sectional representation of
another IDPD with two sensors.
[0037] FIG. 7 is a schematic cross sectional representation of an
IDPD with a window.
[0038] FIG. 8 is a schematic cross sectional representation of an
IDPD with a light source and a detector for reading a dose.
[0039] FIG. 9 is a schematic top, cross sectional and bottom
representation of an IDPD in the form of a credit card.
[0040] FIG. 10 is a schematic cross sectional representation of an
IDPD with a sensor and a scratch-off bar.
[0041] FIG. 11 is schematic cross sectional representation of
another IDPD with a sensor and a scratch-off bar.
[0042] FIG. 12 is a schematic cross sectional representation of an
IDPD with two sensors and a scratch-off bar.
[0043] FIG. 13 is a schematic cross sectional representation of
another IDPD with two sensors and a scratch-off bar.
[0044] FIG. 14 is a schematic cross sectional representation of
another IDPD with two sensors and a scratch-off bar.
[0045] FIG. 15 is a schematic cross sectional representation of an
IDPD with two sensors, scratch-off bars and a FIT indicator.
[0046] FIG. 16 is a block diagram describing the process of
collecting cards, reading all information, reporting and providing
medical treatment.
DESCRIPTION OF THE INVENTION
[0047] The present invention is directed to a radiation dosimeter
in one of the most widely carried form, such as a license,
identification card or access card with at least one self
indicating radiation sensitive sensor and/or a second accredited
sensor where both can be easily machine read at a very high speed
for accuracy. The dosimeter would be particularly useful in the
event of a radiological incident such as a dirty bomb, a nuclear
bomb explosion, or an accident at a nuclear power plant. A sensor
which can be read at a very high speed is embedded in a license,
identification card, or access card which is normally carried by
most people. The sensor may have at least one layer to protect it
from being contaminated either during manufacture, use, and/or
reading and also to protect it from ambient conditions to minimize
false signals. Disclosed also is a reader and a process of
monitoring radiation exposure of the device at a very high speed.
The device has a human and machine readable sensor such as a color
developing or color changing sensor to provide early visual
warning. The human readable sensor may indicate the need for
subsequent machine reading of the same or a second sensor. The
device preferably has at least one indicator for a false signal
and/or expiration of the shelf life. One of the main objectives of
the invention is to determine dose distribution and to minimize the
panic and worry of the people affected by a radiological incident
such as a dirty bomb. It is also an objective to minimize potential
unjustified lawsuits.
[0048] Most of us carry a wallet or a purse and in it we carry a
license, ID card or access card. These devices reflect the
individual's identity. In addition to the above ID devices, many of
us also have a social security card, a passport, a national ID
card, and a number of other similar items. The other similar items
include key/control access cards, VIP cards, membership cards,
IC/smart cards, key tags, luggage tags, bank/ATM cards, school ID
cards, and employee ID cards, including those with RFID. If a
radiation sensor, self reading, electronic, or others such as TLD,
OSL, and RLG, is incorporated in the personal ID devices, it is
possible to determine the dose of everyone in a given population at
any time, especially in an event of a radiological incident. A
personal ID device having a radiation sensor is referred herein as
IDPD or IDPD device or IDPD dosimeter.
[0049] The preferred materials used in the self indicating
radiation sensor of the device are a unique class of compounds
called diacetylenes with a general formula
R'--C.ident.C--C.ident.C--R'', where R' and R'' are substituent
groups which are described further herein. The self indicating
radiation sensitive device is sensitive to all forms of radiation,
with energy greater than that of UV light, which can penetrate the
protective plastic films that cover the sensing strip of the self
indicating radiation sensor. It responds to neutrons, X-ray
typically with an energy higher than 10 KeV, and high energy
electrons/beta particles. Color development of the sensing strip is
essentially independent of dose rate. The self indicating radiation
sensor of the device is approximately tissue equivalent and hence
no dose correction is required. Particles, such as low energy
electrons, protons, alphas, mesons, pions, and heavy ions will be
absorbed by the protective films and will not typically reach the
sensing strip.
[0050] When exposed to radiation such as a "dirty bomb", a nuclear
detonation, or a radiation source, the self indicating radiation
sensor of the device develops color, preferably blue or red,
instantly. The color intensifies as the dose increases thereby
providing the wearer and medical personnel instantaneous
information on cumulative radiation exposure of the victim. The
color intensity of the sensing strip increases with increasing
dose. Dose can be estimated with an accuracy which is better than
20% with color reference chart and better than 10% using a
calibration plot of optical density versus dose or CD camera.
[0051] As described in PCT applications WO2004017095 and
PCT/US2004005860 both of which are incorporated herein by
reference, a self indicating radiation sensor of the device has
most of the desired properties to monitoring and estimating an
accidental high dose of higher than about 0.1 rad instantly and/or
for monitoring annual and lifetime dose. However, currently it does
not have sufficient sensitivity and the methods of monitoring dose
are not validated or accredited by any government agency.
Commercially available radiation dosimeters and detectors such as
TLD, OSL, RLG, X-ray film, and electronic have sufficient
sensitivity and are validated or accredited by agencies such as
National Voluntary Laboratory Accreditation Program (NAVLAP) and
hence considered more reliable and can be presented in a court.
[0052] The invention will be described with particular emphasis on
the preferred embodiments and will be described with reference to
the figures forming an integral part of the specification. In the
figures similar elements will be numbered accordingly.
[0053] Using a proper diacetylene and thickness of the coating, one
can monitor dose lower than 1 rad. These SIRAD dosimeters are now
made to monitor even lower dose, such as 0.01 rad, by using more
sensitive diacetylenes, a thicker sensor, scanners, and a CCD
camera for monitoring color.
[0054] In FIG. 1, a sensor, 1, is sealed in a core layer, 2, of an
IDPD, 100. The core layer, 2, could be transparent, colored or
opaque and can have required printing on top and bottom surfaces.
Sensor, 1, could be a self indicating radiation sensitive sensor or
an accredited sensor such as TLD, OSL, RLG, or an X-ray film or the
sensor could represent both the self indicating radiation sensitive
sensor and the accredited sensor.
[0055] A protective layer, such as Teflon or silicone coating, or
an opaque pouch, 3, as shown in FIG. 2 can be provided to protect
the sensor, 1, and prevent its contamination during manufacturing,
using, and/or reading of IDPD and also to protect from ambient
conditions to minimize false signals.
[0056] With further reference to FIG. 3 the sensor, 1, could reside
in a cavity, 4, of the core layer, 2, and it can be sealed between
a top layer, 5, and bottom layer, 6. The top layer could be
transparent the bottom layer could be opaque for the cavity, 4, in
the core layer for the sensor, 1. The top layer or bottom layer
include a color such as a red colored optical filter to mitigate
the undesirable effect of ambient light without blocking other
wavelengths.
[0057] In one embodiment the machine readable sensor could reside
in the same cavity as the self indicating radiation sensitive
sensor or in a separate cavity. Either sensor can be removed from
the cavity for reading by die cutting or laser cutting.
[0058] As shown in FIG. 4, the top, 5, and the bottom, 6, layers of
IDPD, 100, can either be fused together or can be sealed with
adhesive layers, 7 and 8. The adhesive layers, 7 and 8, could be
made from the same material. The adhesive layers can be made from a
pressure sensitive adhesive but preferred is a hot melt adhesive.
The top and bottom of the cavity may be non-stick or
non-contaminating materials particularly selected from Teflon.RTM.
or silicon. Non-contaminating materials are materials which do not
absorb liquid or water soluble materials.
[0059] As shown in FIG. 5, the IDPD, 100, could have more than one
sensor either of similar type or different types, such as a self
indicating radiation sensitive sensor, 9, and an accredited sensor,
10. They could be located one over the other, next to each other,
or one of them could be outside the IDPD as shown in FIG. 6.
[0060] It is desirable that the sensor be read without removing it
from the IDPD. The self indicating radiation sensitive sensor, OSL,
RLG, ESR, NMR, and similar sensors can be read without removal from
the IDPD. Color development of a self indicating radiation
sensitive sensor can be read with a light source, 14, and a
detector such as a CCD camera, 15, similarly OSL and RLG sensors
can be read by illuminating with one wavelength of UV or visible
light preferably from a laser and monitoring emitted light with a
CCD camera type detector similar to that shown in FIG. 8. This type
of sensor may need a transparent top layer and a window, 13, as
shown in FIGS. 7 and 8. The sensor may have a reflective layer
behind the sensor for higher sensitivity. The IDPD can be read in a
transmission mode as well. In such case IDPD would need two windows
with a light source on one side a detector on the other side. Any
combination of windows may be fixed, removable or liftable. A
removable window is easily reversibly removed by scraping, rubbing
and the like whereas a liftable window is reversible removable and
typically has a portion permanently adhered to act as a hinge. The
windows could also be made from a color optical filter to protect
from ambient light and still maintain readability.
[0061] As shown in FIG. 9, the IDPD, 100, may also have a sensor,
1, and a removable layer, 30, which is preferably opaque to visible
and UV lights but transparent to ionizing radiation such as X-ray
and beta ray. Transparent colored filter could also be used as
window material. The removable layer, 30, could be on both sides as
shown in FIG. 10. As shown in FIG. 11, The IDPD, 100, could have
two sensors, for example one self indicating radiation sensitive
sensor, 9, and the other an accredited sensor, 10, next to each
other and a removable layer either on one side or on both sides of
IDPD, 100, as shown in FIG. 12. As shown in FIG. 13, the sensors
could be one over the other with a removable layer on each side of
IDPD, 100. As shown in FIG. 14, an IDPD could have one or more
indicators for false signals, 31, including those due to
UV/sunlight exposure, pre-determined temperature, prolonged
exposure to high temperatures, tampering, archiving and shelf life
or an all-in-one type indicator, called a FIT indicator. FIT
indicators are described in U.S. patent application Ser. No.
12/293,322 "Time-temperature, UV exposure, and Temperature
indicator" which is incorporated herein by reference. Location of
the sensors and false signal indicator could be anywhere inside, or
outside, the IDPD. A FIT indicator is defined as a false positive,
false negative, UV exposure, temperature, archiving and shelf life
indicators individually or collectively. Instead of a FIT indicator
a different indicator or combination of indicators may be used.
[0062] Once the removable layer is removed, such as by lifting,
scratching off or by wiping off as described in patent application
WO 2006124594 titled "A detector for a UV false positive of
radiation sensitive devices", or transparent colored optical filter
as disclosed in U.S. Provisional Patent Application No. 61/062,771
titled "Self Indicating Radiation Sensors And Dosimeters With
Optical Absorbers And A Liftable Optical Filter" both of which are
incorporated by reference, some of the sensors such as self
indicating radiation sensitive sensor, OSL and RLG can be read,
such as by illumination followed by reading with a detector such as
CCD camera. The IDPD described herein could have a transparent
colored optical filter layer attached or liftable.
[0063] The ESR and NMR type sensor would not need a window and can
be read without any type of window. On the other hand TLD type
sensors would need to be removed, such as by cutting them out and
reading the light emitted at higher temperatures.
[0064] The IDPD shown above could have an indicator for a false
positive, a negative, and/or a tamper indicator which can be
applied on or under any layer.
[0065] In order to protect sensors from undesirable effects such as
UV/sunlight, the sensor may have a UV absorbing layer, a
transparent colored optical filter or an opaque layer on them.
[0066] As shown in FIG. 15A, the top surfaces of the IDPD could
have pictorial or textural information such as name of the user and
number, 18, printed or engraved on either or both of the surfaces.
As shown in FIG. 15B the bottom surface, 21, of the IDPD could also
have a magnetic tape, 19, for storing information about the users
and a location for other information, 20, such as a model number,
serial number, expiration date, user printable area, instructions
for use, etc. The core layer may have an electronic chip and
RadioFrequency Identification Device (RFID) so the information can
be read remotely. The sensor, 1, could be embedded anywhere inside
the IDPD.
[0067] One of the main objectives of the IDPD is to determine dose
distribution and to minimize the panic and worry of the people
affected by a radiological incident such as a dirty bomb. Another
main objective is to minimize potential unjustified lawsuits. FIG.
16 shows a flow diagram for distributing an IDPD to an area of
decontamination.
[0068] In FIG. 16, the IDPD is distributed, 1600, to a subset of
the population. The subset can be defined by location, occupation
or classification. Location is suitable if population masses are to
be protected. For example, if a certain city is suspected of being
particularly vulnerable to a terrorist attack the entire population
of the city, or a select subset, can be provided with an IDPD.
Alternatively, the population may be further subdivided by location
wherein representative members of the location are provided with an
IDPD. For example, if a large city; such as New York, Washington
D.C., Paris, London, Beijing or the like, is particularly
vulnerable than that particular location may be subdivided into
bureaus, towns, or districts and a percentage of the population in
each subdivision may be provided with an IDPD. This eliminates the
necessity for the entire population to have an IDPD but still
provides a wide-spread network of detectors. The IDPD's may be
distributed by occupation. For example, employees involved in
nuclear energy production, emergency response, law enforcement,
border enforcement, maritime monitoring, military operations, etc.
may be provided IDPD's. IDPD's may also be distributed based on a
classification. For example, the classification may involve
particular licenses or access. Individuals with a drivers license,
for example, may be provided with an IDPD as a component of the
physical license or in addition to the physical license. Other
classifications may include such elements as particular access
cards to a physical or virtual location, a financial or computer
based account, or any classification represented by presentation of
a physical element is required for identification, access or
entry.
[0069] Each individual member of the subset of the population
monitors, 1601, the IDPD over a course of time. If no indication of
a radiation event is evident the user, or a representative thereof,
determines if the IDPD has expired, 1603. If the device has not
expired the IDPD continues to be monitored. If the IDPD has expired
the IDPD is disposed of, 1604, and replaced if appropriate.
[0070] Once a preliminary indication of a radiation event is
indicated the process of dose determination proceeds. In a
preferred embodiment the individual, or a representative,
identifies the radiation location, 1605. The IDPD is preferably
collected, 1606, in a manner consistent with good practices related
to sample collection, isolation and retention to insure any result
has the necessary level of integrity. The IDPD is read, 1607, by an
instrument to accurately determine the actual dose. The reading of
the IDPD preferably includes dose, or exposure, and any pertinent
information such as individual, location, occupation or
classification.
[0071] Based on the dose reading a determination is made regarding
the existence of an actionable exposure, 1608. An actionable
exposure is any exposure which is above a threshold to a sufficient
amount to warrant a response. The determination of actionable
exposure preferably includes a determination of a false reading. If
the determination if that there is no actionable exposure the IDPD
is disposed of, 1604. It would be readily understood that disposal
may include a period of archiving to allow for the possibility of a
subsequent test, and, for the purposes of the present invention
disposal indicates removal of the IDPD from the cycle of radiation
detection and it is therefore disposed for the purposes of use.
Disposal also includes activities up to, and including,
irreversible destruction.
[0072] If actionable exposure is determined to be present it is
preferable to generate a report, 1609, and to mitigate the
exposure, 1610. The report may be to the individual or for broader
circulation such as to rescue personnel, military entities,
maintenance personnel and the like for further mitigation
activities. Mitigation is any activity which decreases the risk of
further exposure to the tested individual or any other individual
or facility. Mitigation may also include necessary medical
treatment, decontamination of individuals or property and military
action.
[0073] A system for reading dose for IDPD having a SIRAD type
sensor can include a holder for the IDPD, an illuminator, a
detector, data storage, a data processor and associated processes
as described in a patent application titled "A General Purpose,
High Accuracy Dosimeter Reader" WO2007089799 and references cited
therein which are incorporated herein by reference. Similarly,
commercially available systems with appropriate modifications can
be used for reading OSL, TLD and RLG type sensors of IDPD.
[0074] An IDPD and data can also be archived if needed in the
future.
[0075] Dose can be determined by comparing the read value with
calibration data stored in the data storage such as a hard drive
and a processor of a computer.
[0076] The detector of choice will depend on the type of sensor.
For example, for SIRAD, OSL, TLD and RLG, a photo-detector or a CCD
camera can be used.
[0077] The illumination system will depend upon the sensor. For
example for SIRAD, OSL, and RLG it could be a lamp or a laser
[0078] The top, core, and bottom layers could be any material such
a plastic, paper, or metal. The preferred material is a plastic.
They could be made from natural and synthetic polymers, such as
polyolefins, polyvinyls, polycarbonate, polyester, polyamide, or
copolymer and block copolymers such as a copolymer of
acrylonitrile, butadiene and styrene (ABS) and cellulose acetate.
The most preferred materials for these layers are polyesters,
polycarbonates, polyolefins, polyvinyls and copolymers such as ABS.
These layers could be made from the same or different plastics. The
most preferred materials are films of polyethylene terephthalate,
polyvinylchloride, and polycarbonate.
[0079] The top transparent layer can be polyethylene terephthalate
(PET), glycolated PET (PETG) or polyvinylchloride (PVC). The top
surface is preferably treated physically or chemically for
antiglare and scratch resistance.
[0080] The middle core layer could be a plastic film, such as PVC,
PET or polyolefin, such as Teslin.RTM. or Artisyn.RTM., with
die-cut cavities for sensors. The core layers should preferably be
opaque. The core layer can be printed with any conventional method
of printing.
[0081] The adhesive layers could be a pressure sensitive adhesive
or a low melt adhesive. Other industrial and common adhesives,
including two component adhesives such as those of polyepoxy and
polyurethane can also be used for making adhesive layers. For heat
activated adhesives, it is particularly preferred that the adhesive
has a melting point of less than 100.degree. C. In order to make
the cards tamper resistant, the preferred bonding layer is a heat
activated adhesive or two component bonding materials, such as
polyepoxy or polyurethane, or those that can be cured by
crosslinking. Heat activated adhesive is preferred because it makes
the device tamper resistant and provides a stronger bond than that
provided by a pressure sensitive adhesive.
[0082] A large number of machine readable radiation detectors,
monitors, and dosimeters are used for detecting and monitoring
radiation. The preferred machine readable radiation detectors
include ionization chambers, proportional counters, Geiger-Mueller
counters, scintillation detectors, semiconductor diode detectors
(also referred herein as electronic sensor or electronic
dosimeters), and dosimeters such as self-reading/SIRAD, TLD, OSL,
RLG, and X-ray film. The most preferred machine readable sensors
are self reading, TLD, OSL, RLG, X-ray film, and semiconductor
diode. Provided herein are a sensor which is about 1 mm thick
comprising a SIRAD with a highly sensitive diacetylene which has a
lower limit detection as low as 0.01 rad. The detection limit is
defined as a visible observable color change to the naked eye or
with a machine. This highly sensitive SIRAD can be used instead of
the conventional accredited sensors. In a IDPD there could be
different types of accredited sensors such as TLD, RLG, and OSL in
the same device. More preferably, the sensor is about 0.1 to 5 mm
thick with about 0.9 to 1.1 mm thick being most preferred.
[0083] The size of the IDPD could vary from 1 square mm to any
large size e.g., credit card or 1 meter by 1 meter with more than
one sensors. More preferably, the IDPD is a rectangle with sides
ranging from about 20 mm to about 100 mm. A rectangle with a long
side of about 70 to about 100 mm and a short side of about 40 to
about 60 mm is particularly preferred. The IDPD may also comprise a
void for easy attachment to a key ring or the like.
[0084] An IDPD having the sensors described herein can be in the
form of a credit card, key/control access cards, business cards,
VIP cards, promotion cards, membership cards, IC/smart cards, key
tags, luggage tags, bank cards, ATM cards, school ID, employee ID
and the like. A sticker type IDPD can be applied on commonly
carried items such as a wallet, a purse, and clothing.
[0085] The materials, designs, and processes which can be used for
making dosimeters are described in our previously filed U.S. Pat.
Nos. 5,420,000 titled "Heat fixable high energy radiation imaging
film"; 5,672,465 titled "Polyethyleneimine binder complex films"
and 7,227,158--"A Stick-On Self-Indicating Instant Radiation
Dosimeter" and applications WO 2007097785 titled "Method Of Making
Smart Cards With An Encapsulant" WO 2007089799 titled "A General
Purpose, High Accuracy Dosimeter Reader" WO 2006124594 titled "A
Detector For A UV False Positive Of Radiation Sensitive Devices" US
2006145091 titled "Self Indicating Radiation Alert Dosimeter"; US
2005208290 titled "Thick Radiation Sensitive Devices"; Ser. No.
12/293,322 titled "Time-Temperature, UV Exposure, And Temperature
Indicator" or U.S. Provisional Patent Application No. 61/062,771
titled "Self Indicating Radiation Sensors And Dosimeters With
Optical Absorbers And A Liftable Optical Filter" each of which is
incorporated herein by reference.
[0086] The sensor could have filters to selectively filter off
unintentional radiation such as transparent colored optical filter
or copper, cadmium, etc. Filters are routinely used for TLD, RLG
and OSL type dosimeters. An IDPD could have more than one sensor of
the same type for detection of different energies or types of
radiation such photons, beta/electrons, neutrons, etc.
[0087] An IDPD can be manufactured in large quantities using the
commercially available equipment and procedures for making credit
cards, smart cards, high security ID cards, and bank/ATM cards with
electronic chips and RFID type elements. Tamper resistant and
evident cards also can be made by these processes.
[0088] The present invention provides advantages which are not
otherwise available in the art. Due to the simplicity and size it
is highly suitable as a highly reliable dosimeter for mass
distribution. It is ideally suited as a personal dosimeter assigned
to an individual. In a particularly preferred embodiment the
dosimeter can be coordinated with an additional functionality. For
example, many industrial environments utilize some type of entry
system wherein a credit card sized device must be monitored to
allow entry into a protected area. By incorporating the present
invention into such devices it essentially ensures that the user
has the sensor on their persons thereby increasing the likelihood
of early detection in the case of an industrial radiation event. In
a particularly preferred embodiment, an RFID device can be embedded
thereby rapidly coordinating a detectable device with a location
and/or individual to facilitate rapid deployment of appropriate
emergency response personnel.
[0089] In the case of purposeful exposure, such as in the case with
terrorist activities, the device is particularly useful. Since most
people already carry cards such as credit cards, drivers licenses
etc. and are already in the mindset of having these in close
proximity to their person the present invention takes advantage of
normal human behavior and is available for monitoring radiation
virtually continuously without extra effort. In an event of a
terrorist activity it would allow emergency personnel to rapidly
determine the epicenter of an event and rapidly alert the citizens.
Citizens could then immediately determine if they have been exposed
and those within the cone of exposure could be treated rapidly, the
cone evacuated, and the threat mitigated. A mitigated threat is one
that has been eliminated or contained.
[0090] In a particularly preferred embodiment the device comprises
indicia indicating the individual to which the device is assigned.
This reduces the likelihood of a sensor being a shared device and
increases the likelihood that a positive reading is correlated to
an individual.
[0091] The present invention provides significant social
advantages. Realizing that any exposure can be noticed, and
mitigated, quickly greatly reduces the worry and panic associated
with an attempted attack, whether real or imagined, and decreases
the ability of a would be terrorist to bluff the presence of a
radiation device. Due to the awareness of the possibility of a
terrorist attack even a bluff, wherein a radiation device is stated
to be present when in fact it is not, causes great concern and in
many ways has the financial and emotional impact of an actual
attack. By providing citizens with an early warning this type of
"emotional warfare" can be thwarted. In the case of an actual
attack the number of individuals actually involved is immediately
obvious which decreases the panic and greatly facilitates
mitigation of the problem. Furthermore, since the detectors are
easily read by an individual the present device greatly minimizes
the stress placed on a health care system when faced with a
population wherein some unknown fraction of the population may be
exposed to enough radiation requiring medical treatment. Currently,
there is no mechanism for efficient triage.
[0092] A particular business advantage of the present invention is
the ability to multiply the effective number of inspectors.
Typically, trained inspectors would be responsible for determining
if there is a radiation event in an industrial environment. If a
detector is provided for a large number of individuals each one
becomes a potential inspector since any exposure would be readily
realized even if it is not otherwise detectable by the human
senses.
[0093] The method of manufacturing the IDPD includes those methods
generally relied on for manufacturing laminated products with
elements embossed therein. In one method, layers are preformed and
then combined in a process of lamination wherein the preformed
layers are pressed together with an adhesive there between as
either an additional layer or as a layer which is integral to at
least one formed layer. In another method the IDPD is formed by
injection molding as widely practiced in the art.
[0094] In the general formula, R'--C.ident.C--C.ident.C--R'', where
R' and R'' are the same or different substituent groups. Though
this class of diacetylenes is preferred, other diacetylenes having
the following general formulas can also be used: higher acetylenes:
R'--(C.ident.C).sub.n--R'', where n=3-5; split di and higher
acetylenes: R'--(C.ident.C).sub.m--Z--(C.ident.C).sub.o--R'', where
Z is any diradical, such as --(CH.sub.2).sub.n-- and
--C.sub.6H.sub.4--, and m and o is 2 or higher; and polymeric di
and higher acetylenes: [-A-(C.ident.C).sub.n--B--].sub.x, where A
and B can be the same or different diradical, such as
--(CH.sub.2).sub.b--, --OCONH--(CH.sub.2).sub.b--NHCOO--, and
--OCO(CH.sub.2).sub.bOCO-- where R' and R'' can be the same or
different groups.
[0095] The preferred diacetylenes include those where R' and R''
are selected from: (CH.sub.2).sub.b--H; (CH.sub.2).sub.bOH;
(CH.sub.2).sub.b--OCONH--R1; (CH.sub.2).sub.b--O--CO--R1;
(CH.sub.2).sub.b--O--R1; (CH.sub.2).sub.b--COOH;
(CH.sub.2).sub.b--COOM; (CH.sub.2).sub.b--NH.sub.2;
(CH.sub.2).sub.b--CONHR1; (CH.sub.2).sub.b--CO--O--R1; where
b=1-10, preferably 1-4, and R1 is an aliphatic or aromatic radical,
e.g. C.sub.4-C.sub.6 alkyl or phenyl or substituted phenyl, and M
is a cation, such as Na.sup.+ or (R1).sub.3N.sup.+.
[0096] The preferred diacetylenes are the derivatives of
2,4-hexadiyne, 2,4-hexadiyn-1,6-diol, 3,5-octadiyn-1,8-diol,
4,6-decadiyn-1,10-diol, 5,7-dodecadiyn-1,12-diol and diacetylenic
fatty acids, such as tricosa-10,12-diynoic acid (TC),
pentacosa-10,12-diynoic acid (PC), their esters, organic and
inorganic salts and cocrystallized mixtures thereof. The most
preferred derivatives of the diacetylenes, e.g.
2,4-hexadiyn-1,6-diol, are the urethane and ester derivatives.
[0097] Preferred urethane derivatives are alkyl, aryl, benzyl,
methoxy phenyl, alkyl acetoacetate, fluoro phenyl, alkyl phenyl,
halo-phenyl, cyclohexyl, toyl and ethoxy phenyl of
2,4-hexadiyn-1,6-diol, 3,5-octadiyn-1,8-diol,
4,6-decadiyn-1,10-diol, 5,7-dodecadiyn-1,12-diol. The prefer
urethane derivatives are methyl, ethyl, propyl and butyl
derivatives of 2,4-hexadiyn-1,6-diol, 3,5-octadiyn-1,8-diol,
4,6-decadiyn-1,10-diol, 5,7-dodecadiyn-1,12-diol.
[0098] The following are some of the preferred derivatives of
2,4-hexadiyn-1,6-diol: urethane (--OCONH--) derivatives,
R'CH.sub.2--C.ident.C--C.ident.C--CH.sub.2R', including: hexyl
urethane: 166, R'.dbd.OCONH(CH.sub.2).sub.5CH.sub.3; pentyl
urethane: 155, R'.dbd.OCONH(CH.sub.2).sub.4CH.sub.3; butyl
urethane: 144, R'.dbd.OCONH(CH.sub.2).sub.3CH.sub.3; ethyl
urethane: 122, R'.dbd.OCONHCH.sub.2CH.sub.3; methyl urethane: 111,
R'.dbd.OCONHCH.sub.3; ester (--OCO--) derivatives,
R'''CH.sub.2--C.ident.C--C.ident.C--CH.sub.2R''', including: butyl
ester: 144E, R'''.dbd.OCO(CH.sub.2).sub.3CH.sub.3; ethyl ester:
122E, R'''.dbd.OCOCH.sub.2CH.sub.3; methyl ester: 111E,
R'''.dbd.OCOCH.sub.3; symmetrical diacetylenes including: 156:
R'--C.ident.C--C.ident.C--R'', where
R'.dbd.CH.sub.2OCONH(CH.sub.2).sub.5CH.sub.3 and
R''.dbd.CH.sub.2OCONH(CH.sub.2).sub.4CH.sub.3; cocrystallized
mixtures including: containing 80 weight percent or above of 166;
85:15 mixture of 166 and 156; 90:10 mixture of 166 and 156 and 4:1
mixture of tricosadiynoic acid and pentacosadiynoic acid(TP41).
[0099] The further preferred diacetylenes are derivatives of
3,5-octadiyn-1,8-urethane, 4,6-decadiyn-1,10-urethane and
5,7-dodecadiyn-1,12-urethane, e.g., hexyl urethane:
R'.dbd.OCONH(CH.sub.2).sub.5CH.sub.3; pentyl urethane:
R'.dbd.OCONH(CH.sub.2).sub.4CH.sub.3; butyl urethane:
R'.dbd.OCONH(CH.sub.2).sub.3CH.sub.3; propyl urethane:
R'.dbd.OCONH(CH.sub.2).sub.2CH.sub.3; ethyl urethane:
R'.dbd.OCONHCH.sub.2CH.sub.3; methyl urethane:
R'.dbd.OCONHCH.sub.3.
[0100] The most preferred diacetylenes are the urethane derivatives
such methyl, ethyl, propyl and butyl urethane derivatives of
4,6-decadiyn-1,10-diol, e.g., diacetylene 344
[R'--C.ident.C--C.ident.C--R' where
R'.dbd.OCONH(CH.sub.2).sub.3CH.sub.3.
[0101] The urethane derivatives can be prepared by reacting
diacetylene-diol, e.g., 2,4-hexadiyn-1,6-diol with an appropriate
isocyanates (e.g. n-hexylisocyanate) in a solvent, such as
tetrahydrofuran, using catalysts, such as di-t-butyltin
bis(2-ethylhexanoate) and triethylamine as indicated below:
##STR00001##
[0102] Ester derivatives can be prepared by reacting e.g.,
2,4-hexadiyn-1,6-diol with appropriate acid chlorides in a solvent,
such as dichloromethane, using a base, such as pyridine as the
catalyst; i.e.,
##STR00002##
[0103] Asymmetrical diacetylenes can be prepared by the
Cadiot-Chodkiewicz type reaction methods.
[0104] Though individual diacetylenes can be used, it is desirable
to alter the reactivity of diacetylenes by cocrystallization.
Cocrystallization can be achieved by dissolving two or more
diacetylenes, preferably conjugated, prior to molding. For example,
when TC and PC are co-crystallized, the resulting cocrystallized
diacetylene mixture, such as TP41 (4:1 mixture of TC:PC) has a
lower melting point and significantly higher radiation reactivity.
The reactivity can also be varied by partial neutralization of
diacetylenes having --COOH and --NH.sub.2 functionalities by adding
a base, such as an amine, NaOH, Ca(OH).sub.2, Mg(OH).sub.2 or an
acid, such as a carboxylic acid, respectively.
[0105] Other preferred diacetylenes are amides of fatty chain acid,
such as TC and PC. The preferred amides are:
TCAP.dbd.CH.sub.3(CH.sub.2).sub.9--C.ident.C--C.ident.C--(CH.sub.2).sub.8-
--CONH--(CH.sub.2).sub.3CH.sub.3;
PCAE=CH.sub.3(CH.sub.2).sub.11--C.ident.C--C.ident.C--(CH.sub.2).sub.8--C-
ONH--CH.sub.2CH.sub.3;
PCAP.dbd.CH.sub.3(CH.sub.2).sub.11--C.ident.C--C.ident.C--(CH.sub.2).sub.-
8--CONH--(CH.sub.2).sub.3CH.sub.3;
PCACH.dbd.CH.sub.3(CH.sub.2).sub.11--C.ident.C--C.ident.C--(CH.sub.2).sub-
.8--CONH--C.sub.6H.sub.5; and
TCACH.dbd.CH.sub.3(CH.sub.2).sub.9--C.ident.C--C.ident.C--(CH.sub.2).sub.-
8--CONH--C.sub.6H.sub.5.
[0106] In order to maximize radiation reactivity, 166 can be
co-crystallized with other diacetylenes, e.g. 155, 157, 154 and
156, which are described above. Though certain diacetylenes, such
as 155, increase the reactivity of 166, the partially polymerized
cocrystallized diacetylenes provide a red color upon melting.
However, 156 increases the radiation reactivity of 166 and provides
a blue color upon melting the partially polymerized diacetylene
mixture. 166 can be cocrystallized with different amounts of 156.
Preferred is where the amount is 5-40 weight percent of 156 to 166,
most preferred are 90:10 and 85:15 respective weight ratios of
166:156. As used herein "9010" and "8515" refer to these specific
cocrystallized mixtures.
[0107] Other asymmetrical derivatives, including different
functionalities, e.g., ester as one substituent and urethane as the
other, can also be prepared. A procedure for synthesis of a 90:10
mixture of 166 and 16PA is given in U.S. Pat. No. 5,420,000. Using
the general procedures given in U.S. Pat. No. 5,420,000, it is
possible to prepare a variety of other asymmetrical derivatives and
their mixtures for cocrystallization.
[0108] Polymers having diacetylene functionality [e.g.,
{--R'--(C.ident.C).sub.n--R''--}.sub.x, where R' and R'' can be the
same or different diradical, such as --(CH.sub.2).sub.n--,
--OCONH--(CH.sub.2).sub.n--NHCOO-- and --OCO(CH.sub.2).sub.nOCO--
in their backbones are also preferred because of the fact that they
are polymeric and do not require a binder.
[0109] The preferred diacetylenes are those which have a low (e.g.,
below about 150.degree. C.) melting point and crystallize rapidly
when cooled at a lower temperature, e.g. room temperature.
[0110] Another class of preferred diacetylenic compounds is those
having an incorporated metal atom and they can be used as built-in
converters. Diacetylenes having functionalities, such as amines,
ethers, urethanes and the like can form complexes with inorganic
compounds. It is possible to synthesize diacetylenes having an
internal converter, which is covalently bonded, such as boron and
mercury, lithium, copper, cadmium, and other metal ions. For
example, the --COOH functionality of TC, PC and TP41 can be
neutralized with lithium ion and synthesis of
R--C.ident.C--C.ident.C--Hg--C.ident.C--C.ident.C--R is reported
(M. Steinbach and G. Wegner, Makromol. Chem., 178, 1671 (1977)).
The metal atom, such as mercury atom thereby incorporated into the
diacetylene can emit short wavelength irradiation upon irradiation
with photons and electrons.
[0111] The following terminologies are used for defining the
reactivity (polymerizability) of a diacetylene. The polymerizable
form of a diacetylene(s) is referred to as "active". If a
diacetylene is polymerizable with radiation having energy higher
than 4 eV, wavelength shorter than 300 nm, then it is referred to
as "radiation active". If it is polymerizable upon thermal
annealing then it is referred to as "thermally active". A form of
diacetylene, which displays little or no polymerization, is
referred to as "inactive". If it displays little polymerization
with radiation (having energy higher than 4 eV) then it is referred
to as "radiation inactive" and if it is significantly
nonpolymerizable upon thermal annealing, then it is referred to as
"thermally inactive". Diacetylenes having
reactivity/polymerizability characteristics in between these
definitions are referred to as "moderately active". The most
preferred form of diacetylene is one, which is highly radiation
reactive and displays little or no thermal reactivity. However,
diacetylenes, which are radiation active also usually, have some
thermal reactivity. Hence, the preferred form of diacetylene is
one, which is highly to moderately radiation active with little or
no thermal reactivity. Thermal reactivity can be decreased and
radiation reactivity can be increased by cocrystallization and
molecular complexation. As an alternative, the shaped-articles can
be stored at a lower temperature to slow down the thermal
reactivity.
[0112] The invention has been described with particular reference
to the preferred embodiments without limit thereto. One of skill in
the art would readily appreciate additional modifications and
embodiments which are not specifically stated but which are within
the scope of the invention as set forth in the claims appended
hereto.
* * * * *