U.S. patent application number 13/713833 was filed with the patent office on 2013-06-20 for method of deacidifying cellulose based materials.
This patent application is currently assigned to HONEYWELL INTERNATIONAL, INC.. The applicant listed for this patent is Honeywell International, Inc.. Invention is credited to Andrew J. POSS, Rajiv R. SINGH, Raymond H. THOMAS.
Application Number | 20130158250 13/713833 |
Document ID | / |
Family ID | 48610780 |
Filed Date | 2013-06-20 |
United States Patent
Application |
20130158250 |
Kind Code |
A1 |
THOMAS; Raymond H. ; et
al. |
June 20, 2013 |
METHOD OF DEACIDIFYING CELLULOSE BASED MATERIALS
Abstract
Provided are compositions and methods of deacidifying a
cellulose-based material. The compositions include a
hydrohalo-olefin and a deacidification agent dispersed within the
hydrohalo-olefin. Cellulose-based materials are contacted with the
composition for a sufficient time to increase the pH of the
material.
Inventors: |
THOMAS; Raymond H.;
(Pendleton, NY) ; SINGH; Rajiv R.; (Getzville,
NY) ; POSS; Andrew J.; (Kenmore, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Honeywell International, Inc.; |
Morristown |
NJ |
US |
|
|
Assignee: |
HONEYWELL INTERNATIONAL,
INC.
Morristown
NJ
|
Family ID: |
48610780 |
Appl. No.: |
13/713833 |
Filed: |
December 13, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61576667 |
Dec 16, 2011 |
|
|
|
Current U.S.
Class: |
536/56 ;
252/189 |
Current CPC
Class: |
D21H 17/11 20130101;
D21H 21/24 20130101; D21H 25/02 20130101; D21H 17/74 20130101; D21H
17/64 20130101; D21H 25/18 20130101 |
Class at
Publication: |
536/56 ;
252/189 |
International
Class: |
D21H 25/02 20060101
D21H025/02 |
Claims
1. A method of deacidifying a cellulose based material comprising:
providing a composition comprising a hydrohalo-olefin and a
deacidification agent dispersed in said hydrohalo-olefin; and
increasing the pH of a cellulose-based material by contacting said
material with the composition.
2. The method of claim 1 wherein said hydrohalo-olefin includes
about two to about six carbon atoms.
3. The method of claim 1 wherein said hydrohalo-olefin includes
about three to about five carbon atoms.
4. The method of claim 1 wherein said hydrohalo-olefin has a
boiling point of from about -29.0.degree. C. to about 50.degree.
C.
5. The method of claim 1 wherein said hydrohalo-olefin is a
compound according to formula I ##STR00003## where each R is
independently Cl, F, Br, I or H and at least one R is a halogen and
at least one R is a hydrogen; R' is (CR.sub.2).sub.nY; Y is
CRF.sub.2; and n is 0, 1, 2 or 3.
6. The method of claim 1 wherein said hydrohalo-olefin is a
hydrofluoro-olefin.
7. The method of claim 6 wherein the hydrofluoro-olefin is selected
from the group consisting of a tetrafluoropropene, a
trifluoropropene, a heptafluorobutene, a heptafluoropentene, and
combinations thereof.
8. The method of claim 1 wherein the hydrohalo-olefin is a
hydrochlorofluoro-olefin.
9. The method of claim 8 wherein the hydrochlorofluoro-olefin is a
chlorotrifluoropropene.
10. The method of claim 1 wherein the hydrohalo-olefin is selected
from the group consisting of HCFO-1233zd, HFO-1234ze, HFO-1234yf,
HFO-1243zf, HFO-1327my, HFO-1327cyc, HFO-1447fzy, HFO-1447fycc,
11. The method of claim 10 wherein the hydrohalo-olefin is
HCFO-1233zd.
12. The method of claim 1 wherein said deacidification agent is in
particle form.
13. The method of claim 12 wherein said deacidification agent
particles have a predominant particle size of from about 0.01 to
about 1.0 micron.
14. The method of claim 12 wherein said deacidification agent is
selected from the group consisting of metal oxides, metal
hydroxides, metal carbonates, metal salts, and combinations of two
or more thereof.
15. The method of claim 12 wherein said deacidification agent is
selected from the group consisting of oxides, hydroxides,
carbonates, and combinations of two or more thereof, of Group IA or
Group IIA metals.
16. The method of claim 15 wherein said deacidification agent is
magnesium oxide.
17. The method of claim 1 wherein said composition further
comprises a surfactant.
18. The method of claim 17 wherein said surfactant is a fluorinated
surfactant.
19. The method of claim 1 wherein said contacting step comprises
immersing at least a portion of said cellulose-based material in
said composition.
20. The method of claim 1 wherein said contacting step comprises
spraying said composition onto said cellulose-based material.
21. The method of claim 1 wherein said increasing step further
comprises evaporating the hydrohalo-olefin from said material
subsequent to said contacting step to deposit at least a portion of
said deacidifying agent on said cellulose-based material.
22. A deacidification composition comprising; a hydrohalo-olefin;
and a deacidification agent dispersed in said hydrohalo-olefin.
23. The method of claim 22 wherein said hydrohalo-olefin includes
about two to about six carbon atoms.
24. The method of claim 22 wherein said hydrohalo-olefin includes
about three to about five carbon atoms.
25. The method of claim 22 wherein said hydrohalo-olefin has a
boiling point of from about -29.0.degree. C. to about 50.degree.
C.
26. The method of claim 22 wherein said hydrohalo-olefin is a
compound according to formula I ##STR00004## where each R is
independently Cl, F, Br, I or H and at least one R is a halogen and
at least one R is a hydrogen; R' is (CR.sub.2).sub.nY; Y is
CRF.sub.2; and n is 0, 1, 2 or 3.
27. The method of claim 22 wherein said hydrohalo-olefin is a
hydrofluoro-olefin.
28. The method of claim 27 wherein the hydrofluoro-olefin is
selected from the group consisting of a tetrafluoropropene, a
trifluoropropene, a heptafluorobutene, a heptafluoropentene, and
combinations thereof.
29. The method of claim 22 wherein the hydrohalo-olefin is a
hydrochlorofluoro-olefin.
30. The method of claim 29 wherein the hydrochlorofluoro-olefin is
a chlorotrifluoropropene.
31. The method of claim 22 wherein the hydrohalo-olefin is selected
from the group consisting of HCFO-1233zd, HCFO-1233zd, HFO-1234ze,
HFO-1234yf, HFO-1243zf, HFO-1327, HFO-1447, isomers thereof and
combinations thereof.
32. The method of claim 31 wherein the hydrohalo-olefin is
HCFO-1233zd.
33. The composition of claim 22 wherein said deacidification agent
is selected from the group consisting of metal oxides, metal
hydroxides, metal carbonates, metal salts, and combinations of two
or more thereof.
34. The composition of claim 22 wherein said deacidification agent
is selected from the group consisting of oxides, hydroxides,
carbonates, and combinations of two or more thereof, of Group IA or
Group IIA metals.
35. The composition of claim 22 wherein said deacidification agent
comprises magnesium oxide.
36. The composition of claim 22 wherein said composition further
comprises a surfactant.
37. The composition of claim 36 wherein said surfactant is a
fluorinated surfactant.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to U.S. Provisional
Application Ser. No. 61/576,667, filed Dec. 16, 2011, the contents
of which are incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates, in part, to the
deacidification of cellulose-based materials. In particular, the
present invention relates to the use of hydrofluoro-olefins and/or
hydrochlorofluoro-olefins to reduce the acidity associated with
certain cellulose-based materials.
BACKGROUND OF THE INVENTION
[0003] The deterioration of paper, books, newspaper, and other
cellulose-based materials is a problem of growing concern
throughout the world. It has been estimated, for example, that of
the approximately 20 million books in the collection of the Library
of Congress, about 30% are in such a state of deterioration that
they cannot be circulated. At the New York Library, it was
discovered that nearly half of the more than five million books
housed therein are subject to severe deterioration. In addition, it
is estimated that 97% of all the books published between 1900 and
1949 have a useful life of no more than about 50 years.
[0004] A major cause associated with the deterioration of
cellulose-based materials is the inherent acidity of such
materials. The manufacture of paper and other cellulose materials
often requires the addition of acids and acidic chemicals to reduce
absorbency and to allow the paper products to accept inks and dyes.
In addition, the manufacturing processes of these materials often
include the introduction of additives via acidic mechanisms.
Unfortunately, these manufacturing processes often result in
cellulose-based products having residual acidic material. The
cellulose-based products tend to have low pH values and,
accordingly, tend to undergo slow, but relentless, acid
deterioration.
[0005] U.S. Pat. No. 4,522,843 suggests that this problem can be
solved by using a dispersion of a basic metal salt into a
chlorofluorocarbon such as trichlorofluoromethane,
trichlorotrifluoroethane and dichlorotetrafluoroethane and mixtures
therof. In US 2003/0150571, the inventors point out that these
substances are chlorofluorocarbons and contribute significantly to
the depletion of the atmospheric ozone layer. They propose the use
hydrofluorocarbons which do not contribute to the depletion of the
ozone layer and also have physical properties that are appropriated
for this application.
[0006] Since the time of that application, there has been growing
concern about substances with high global warming potentials. Such
substances have a direct contribution to global warming.
Hydrofluorocarbons such as described in US2003/0150571 fall into
this category. There is therefore a need for compositions that can
be used for the deacidification of the cellulose materials.
SUMMARY OF THE INVENTION
[0007] In certain embodiments, the present invention relates to a
deacidification composition comprising (a) dispersing medium
comprising, and preferably comprising in major proportion by
weight, one or more hydrohalo-olefin(s) and (b) a deacidification
agent dispersed in the dispersing medium, and even more preferably
dispersed in the one or more hydrohalo-olefin(s). Preferably, the
one or more hydrohalo-olefin(s) contain from two to six carbon
atoms, and more preferably in certain embodiments three to five
carbon atoms. In further aspects, the one or more
hydrohalo-olefin(s) have a boiling point or boiling range of from
about -29.0.degree. C. to about 50.degree. C.
[0008] In certain preferred embodiments, the preferred
hydrohalo-olefin of the present invention comprises a compound
according to formula I
##STR00001## [0009] where each R is independently Cl, F, Br, I or H
and at least one R is a halogen and at least one R is a hydrogen;
[0010] R' is (CR.sub.2).sub.nY; [0011] Y is CRF.sub.2; and [0012] n
is 0, 1, 2 or 3. Such compounds include hydrofluoro-olefins, which
may be selected from the group consisting of a tetrafluoropropene,
a trifluoropropene, a heptafluorobutene, a heptafluoropentene, and
combinations thereof. Such compounds also include
hydrochlorofluoro-olefins, which may be provided as a
chlorotrifluoropropene. Non-limiting examples of such
hydrohalo-olefins include, but are not limited to, one or more of
HCFO-1233zd, HFO-1234ze, HFO-1234yf, HFO-1243zf, HFO-1327my,
HFO-1327cyc, HFO-1447fzy, HFO-1447fycc, including isomers thereof.
In certain embodiments, the hydrohalo-olefin includes
HCFO-1233zd.
[0013] Any known deacidification agent may be used according to the
broad scope of the present invention. In preferred embodiments, the
deacidification agent comprises metal oxides, metal hydroxides,
metal carbonates, metal salts, and combinations of two or more
thereof. In certain aspects, it is a Group IA or Group IIA metal,
which may include Group IA or Group IIA metal oxides, metal
hydroxides, metal carbonates, and combinations thereof. In certain
preferred embodiments, the deacidification agent comprises
magnesium oxide. In certain preferred embodiments, the
deacidification agent is in particle form and may have a
predominant particle size of from about 0.01 to about 1.0
micron.
[0014] The dispersing medium may include, in addition to the one or
more hydrohalo-olefins, any one or more of several components in
order to aid in, modulate and/or enhance the dispersing function or
to provide any other desired function to the composition consistent
with intended purpose. For example, the dispersing medium may also
include one or more surfactants, which may be provided to aid
dispersion of the deacidification agent within the
hydrohalo-olefin. Such surfactants may include a fluorinated
surfactant or any other surfactant able to obtain the effects
provided herein.
[0015] The present invention also relates to methods of
deacidifying a cellulose based material by providing a composition
according to the present invention; and increasing the pH of a
cellulose-based material by contacting said material with the
composition. In certain embodiments, the contacting step may
include immersing at least a portion of the cellulose-based
material in the composition. The contacting step may also, or
alternatively, include spraying the composition onto said
cellulose-based material. The hydrohalo-olefin in preferred
embodiments is then evaporated to deposit at least a portion of the
deacidifying agent on the cellulose-based material.
DETAILED DESCRIPTION OF THE INVENTION
[0016] The present invention relates, in part, to compositions and
methods of deacidifying cellulose-based materials that are not only
adaptable for use with a wide range of deacidification agents, but
also tend to be more environmentally-friendly and less costly than
prior art processes. In one aspect, the present invention relates
to the discovery that halogenated olefins, including
hydrofluoro-olefins ("HFO") and hydrochlorofluoro-olefins ("HCFO"),
can be used in conjunction with a wide variety of basic materials
to form compositions suitable for use in deacidifying acidic
cellulosic materials.
[0017] Applicants have determined, for example, that halogenated
olefins having a boiling point of, or mixtures or blends of
halogenated olefins having a boiling range within, from about
-29.0.degree. C. to about 50.degree. C. are capable of dispersing
effective amounts of deacidifying agents therein such that the
composition comprising the halogenated olefins and deacidifying
agents may be advantageously introduced to acidic materials to
increase the pH associated therewith. The preferred forms of the
present compositions are similarly advantageous because they do not
contribute to ozone depletion and have minimal ODP values. Thus,
they are environmentally benign. The preferred halogenated olefins
according to the present invention are also relatively volatile,
and thus, can be removed easily from the cellulosic materials
without the need to resort to conventional drying methods that are
expensive and time-consuming. Unlike prior art deacidifying
compositions, compositions of the present method are also
relatively inexpensive, and exhibit additional beneficial
properties such as, low flammability, low toxicity, and low
reactivity.
[0018] As used herein, the term "hydrohalo-olefins" relates to any
organic compound having at least one double bond between two carbon
atoms, at least one halogen and at least one hydrogen. Such
compounds are inclusive of, but not limited to, hydrofluoro-olefins
and hydrochlorofluoro-olefins. As used herein, the term
"hydrofluoro-olefin" or "HFO" relates to any organic compound
having at least one double bond between two carbon atoms, at least
one fluorine and at least one hydrogen. As used herein the term
"hydrochlorofluoro-olefin" or "HCFO" relates to any organic
compound having at least one double bond between two carbon atoms,
at least one fluorine, at least one chlorine, and at least one
hydrogen.
[0019] In certain aspects, the hydrohalo-olefin contains C2 to C6
carbon atoms, or C3 to C5 carbon atoms, wherein the double bond is
between two of the carbons. As used herein, the term C2 to C6
refers to any olefin having from two to six carbon atoms in the
backbone, and similarly the term C3 to C5 means any olefin having
from three to five carbon atoms in the backbone.
[0020] In one aspect of the foregoing, the hydrohalo-olefin,
hydrofluoro-olefin, and/or hydrochlorofluoro-olefin is compound
according the following formula I:
##STR00002## [0021] where each R is independently Cl, F, Br, I or H
and at least one R is a halogen and at least one R is a hydrogen;
[0022] R' is (CR.sub.2).sub.nY; [0023] Y is CRF.sub.2; and [0024] n
is 0, 1, 2 or 3. In embodiments wherein the compound is a
hydrofluoro-olefin, at least one R is a hydrogen and at least one R
is a fluorine. In embodiments where the compound is a
hydrochlorofluoro-olefin, at least one R is a hydrogen, at least
one R is a fluorine and at least one R is a chlorine.
[0025] Useful hydrofluoro-olefins, in accordance with the
foregoing, include but are not limited to one or more
tetrafluoropropenes (HFO-1234), trifluoropropene (HFO-1243),
heptafluorobutene (HFO-1327), heptafluoropentene (HFO-1447) and/or
a fluorohexene. Useful hydrochlorofluoro-olefins, in accordance
with the foregoing, include but are not limited to
chlorotrifluoropropene (HCFO-1233) and/or a chlorofluorohexene.
[0026] In certain aspects, the hydrohalo-olefin, hydrofluoro-olefin
and/or hydrochlorofluoro-olefin is substantially non-toxic. That
is, in certain aspects, the hydrohalo-olefin, hydrofluoro-olefin
and/or hydrochlorofluoro-olefin has a very low acute toxicity
level, as measured by inhalation exposure to mice and/or rats.
[0027] The term "HFO-1234" is used herein to refer to all
tetrafluoropropenes. Among the tetrafluoropropenes are included,
but not limited to, 2,3,3,3-tetrafluoropropene (HFO-1234yf) or cis-
and/or trans-1,1,1,3-tetrafluoropropene (HFO-1234ze). The term
"HFO-1234ze" is used herein generically to refer to
1,1,1,3-tetrafluoropropene, independent of whether it is the cis-
or trans- form. The terms "cisHFO-1234ze" and "transHFO-1234ze" are
used herein to describe the cis- and trans- forms of
1,1,1,3-tetrafluoropropene respectively. The term "HFO-1234ze"
therefore includes within its scope cisHFO-1234ze, transHFO-1234ze,
and all combinations and mixtures of these. In certain aspects of
the present invention, the hydrofluoro-olefin comprises, consists
essentially of, or consists of cisHFO-1234ze. In further
embodiments, the hydrofluoro-olefin comprises, consists essentially
of, or consists of transHFO-1234ze, and in even further embodiments
the hydrofluoro-olefin comprises, consists essentially of, or
consists of cisHFO-1234ze and transHFO-1234ze.
[0028] The term "HCFO-1233" is used herein to refer to all
trifluoromonochloropropenes. Among the trifluoromonochloropropenes
are included, but not limited to, cis- and/or
trans-1,1,1-trifluoro-3-chlororopropene (HCFO-1233zd). The terms
"cisHCFO-1233zd" and "transHCFO-1233zd" are used herein to describe
the cis- and trans- forms of 1,1,1-trifluoro-3-chlororopropene,
respectively. The term "HCFO-1233zd" therefore includes within its
scope cisHCFO-1233zd, transHCFO-1233zd, and all combinations and
mixtures of these. In certain aspects of the present invention, the
hydrochlorofluoro-olefin comprises, consists essentially of, or
consists of cisHCFO-1233zd. In further embodiments, the
hydrochlorofluoro-olefin comprises, consists essentially of, or
consists of transHCFO-1233zd, and in even further embodiments the
hydrochlorofluoro-olefin comprises, consists essentially of, or
consists of cisHCFO-1233zd and transHFO-1233zd.
[0029] Specific preferred embodiments of such compounds are
provided below in Table 1, but such compositions are not limiting
to broad scope the invention. Compounds of the present invention
may also include any and all isomers thereof and/or alternative
compounds in accordance with the foregoing.
TABLE-US-00001 TABLE 1 HFO or HCFO Molecular formula NBP (.degree.
C.) HCFO-1233zd(E) CF3CH=CHCl 19.0 HFO-1234ze(E) CF3CH=CHF -19.0
HFO-1234ze(Z) CF3CH=CHF 9.0 HFO-1234yf CF3CF=CHF -28.0 HFO-1243zf
CF3CH=CH2 -25.2 HCFO-1233zd(Z) CF3CH=CHCl 38.0 HFO-1327my(Z)
CF3CF=CHCF3 8.0 HFO-1327cyc CF2=CFCF2CHF2 20-21 HFO-1447fzy
CF3CF(CF3)CH=CH2 21-25 HFO-1447fycc CF2HCF2CF2CF=CH2 32.0
In certain embodiments, the compositions of the present invention
include, and preferably in major proportion by weight, and even
more preferably in certain embodiments consist essentially of
1233zd, which exhibits desirable non-flammability, non-toxicity and
environmentally acceptability. Such compositions may include
1233zd, alone, or in combination with one or more of the foregoing
hydrohalo-olefins, hydrofluoro-olefins, and/or
hydrochlorofluoro-olefins.
[0030] The dispersing medium, and in particular the
hydrohalo-olefin(s), may be provided in any effective amount to act
as a carrier for the deacidification agent and deliver it to the
target substrate of interest. In certain non-limiting aspects, the
compositions of the present invention comprise greater than 50 wt %
of one of more hydrohalo-olefins, based on the total weight of the
composition. In further embodiments, the compositions comprise
about 75 wt. % or more, about 80 wt. % or more, about 85 wt. % or
more, about 90 wt. % or more, about 95 wt. % or more, or about 99
wt. % or more of the hydrohalo-olefin(s). In certain non-limiting
embodiments, the hydrohalo-olefin(s) comprises from about 1 to
about 99 weight percent of the composition, from about 50 to about
99 wt. % of the composition, from about 75 to about 99 wt. % of the
composition, from about 80 to about 99 wt. % of the composition,
from about 90 to about 99 wt. % of the composition, or from about
90 to about 95 wt. % of the composition, based on the total weight
of the composition.
[0031] As noted above, compositions of the present invention
include one or more deacidification agents. A "deacidification
agent," as used herein, means a basic substance that can be used in
conjunction with one or more of the hydrohalo-olefins provided
herein to deacidify cellulose-based materials. Examples include
oxides, hydroxides, carbonates, and bicarbonates of zinc and metals
in Group 1 and Group II of the Periodic Table. According to certain
embodiments, the deacidification agents of the present invention
are oxides, hydroxides, carbonates and bicarbonates of zinc,
magnesium, sodium, potassium, calcium, or combinations of two or
more thereof. Non-limiting examples of such agents include zinc
carbonate, zinc bicarbonate, zinc oxide, magnesium carbonate,
magnesium bicarbonate, magnesium oxide, magnesium methyl carbonate,
calcium oxide, sodium hydroxide, potassium hydroxide, calcium
hydroxide, and combinations of two or more thereof. More preferred,
but non-limiting, deacidification agents include magnesium oxide
and magnesium methyl carbonate. An especially preferred, but
non-limiting, deacidification agent is magnesium oxide.
[0032] In certain embodiments, the deacidification agents of the
present invention are used in particle form. According to certain
embodiments, the deacidification agent particles are of a size
suitable for being depositing on a cellulose-based material to
cause deacidification of the material without substantially
impairing images, if any, thereon. The predominant particle size
(i.e. the size of from about 90 to about 99%, or from about 95 to
about 99% of the particles) is from about 0.01 to about 1.0 micron.
According to certain other embodiments, the predominant particle
size is from about 0.2 to about 0.5 micron. The particle surface
area is from about 50 to about 200 m.sup.2/g BET, from about 100 to
about 200 m.sup.2/g, or about 170 m.sup.2/g.
[0033] A variety of deacidification agent particles suitable for
use in the present invention are available commercially and/or can
be prepared using processes known in the art. As will be recognized
by those of skill in the art, processes for preparing alkaline
metal particles include burning elemental metals and collecting the
resulting smoke, attrition of preformed oxides, calcination of
elemental salts, and the like. In light of the disclosure herein,
those of skill in the art will readily be able to obtain
deacidification agent particles suitable for use in the present
invention.
[0034] The deacidification agent may be provided in any effective
amount to achieve the objectives identified herein. In certain
non-limiting aspects, the compositions of the present invention
comprise about 50 wt % or less of the deacidification agent, based
on the total weight of the composition. In further embodiments, the
compositions comprise about 25 wt. % or less, about 20 wt. % or
less, about 15 wt. % or less, about 10 wt. % or less, about 5 wt. %
or less, or about 1 wt. % or less of the deacidification agent. In
certain non-limiting embodiments, the deacidification agent
comprises from about 1 to about 99 weight percent of the
composition, from about 1 to about 50 wt. % of the composition,
from about 1 to about 25 wt. % of the composition, from about 1 to
about 15 wt. % of the composition, from about 1 to about 10 wt. %
of the composition, or from about 5 to about 10 wt. % of the
composition, based on the total weight of the composition.
[0035] According to certain embodiments, the compositions used in
the present invention further comprise a surfactant, which may aid
in the dispersion of the dacidification agent in the
hydrohalo-olefin. Any of a wide range of surfactants are suitable
for use in the present invention and may include, but are not
limited to ionic surfactants, anionic surfactants, cationic
surfactants, and/or non-ionic surfactants, any one of which may
optionally be halogenated. In certain aspects, preferred, but
non-limiting, surfactants used in the present invention are
fluorinated surfactants, such as, for example, Fluorad, FC740
(approximately 50% petroleum naptha and 50% fluoroaliphatic
polymeric esters) and FC721 available commercially from 3M and
Solsperse 3000 and 6000 available from ICI Corporation.
[0036] The amounts of deacidification agent, hydrohalo-olefin, and
surfactant to be used for any particular application will depend on
a number of factors including the length of treatment of the
cellulose material with the deacidification composition and the
amount of deposition of deacidification agent required. In general,
it is desirable that an effective amount of deacidification agent
is used with a given hydrohalo-olefin such that the resulting
composition contains a minimum concentration of agent dispersed
therein over at least the length of time needed to deposit the
agent on cellulosic material. In certain embodiments, the addition
of a surfactant may help increase the dispersibility of
deacidification agent in the hydrohalo-olefin.
[0037] According to certain embodiments, the concentration of the
deacidification agent in the composition is from about 0.001 to
about 0.5 weight percent based on the total weight of the
compositions. According to other embodiments, the deacidification
agent concentration is from about 0.01 to about 0.4 weight
percent.
[0038] According to certain embodiments, the surfactant has a
concentration of from about 0.005 to about 1.0 weight percent based
on the total weight of the deacidifying composition. Alternatively,
the concentration is from about 0.005 and 0.5 weight percent.
[0039] In light of the disclosure contained herein those of skill
in the art will readily be able to formulate HFC/deacidification
agent compositions suitable for use in a wide range of applications
of the present invention.
[0040] The contacting step of the present invention involves
contacting at least a portion of a cellulose-based material with a
composition of the present invention to increase the pH associated
with the cellulose material. Any of a wide range of cellulose-based
materials can be used in the present methods. For example, suitable
materials include paper and paper products, books, wood and wood
products, combinations of two or more thereof, and the like.
[0041] Any of a wide range of methods for contacting the acidic
cellulose material with a composition of the present invention can
be used. Examples of suitable contacting methods include immersion
of the cellulose material in the composition, adding the
composition dropwise to the cellulose material, spraying the
composition onto the cellulose material, combinations of two or
more thereof, and the like. In aspects where the composition is
applied as a sprayable composition, it may be provided as an
aerosol using any of the foregoing or otherwise known
propellants.
[0042] Optionally, the use of electrostatic attraction may be used
in conjunction with the above methods to enhance deposit of
materials on paper. According to certain embodiments, the step of
contacting the cellulose material involves contacting substantially
the entire surface area of the cellulose material with the
composition such that removal of the composition results in
lowering the acidity of the cellulose material.
[0043] The contacting step of the present invention may further
comprise the step of removing the hydrohalo-olefin from the
cellulosic material to deposit at least a portion of the
deacidification agent on the cellulosic material. Any known methods
for removing the hydrohalo-olefin may be used according to the
present invention. In certain embodiments, the removing step
comprises evaporating the hydrohalo-olefin from the cellulosic
material. According to certain embodiments, the evaporating step
comprises changing the pressure and/or temperature to which the
hydrohalo-olefin and cellulosic material are exposed such that the
hydrohalo-olefin is converted to the gaseous state.
[0044] Once a cellulose material has been deacidified according to
the present invention, the removed hydrohalo-olefin solvent can be
recycled for further use. In this manner, the present invention
allows for the deacidification of cellulosic materials without the
need for time-consuming solvent-removing drying steps and excess
clean-up.
[0045] The present invention is more fully illustrated by the
following non-limiting examples. It will be appreciated that
variations in proportions and alternatives in elements of the
components of the invention will be apparent to those skilled in
the art and are within the scope of the invention.
EXAMPLES
Example 1
[0046] This example illustrates one method of deacidifying paper
according to the present invention.
[0047] One thousand (1000) grams of 1233zd are mixed with 3.2 grams
of magnesium oxide and 0.8 grams of surfactant FC-740. The mixture
is placed in a 2 liter beaker and stirred. A cooling coil is placed
on the lip of the beaker to condense and recirculate 1233zd vapor.
Four samples of 63 year old paper are prepared and the acidity of
each sample is measured using the TAPPI509 om-96 method, a copy of
a document describing this method is attached hereto and is
incorporated herein by reference. The pH measurement of each sample
is about 4.6. Each sample is dipped in the mixture in the beaker
for twenty seconds and allowed to dry for 5 minutes. The solvent
evaporates off very quickly. The pH of each sample is then
measured. The average pH of the four samples is about 8.9
Example 2
[0048] This example illustrates another method of deacidifying
paper according to the present invention.
[0049] A 150 cc aerosol can is loaded with 50 grams of a suspension
prepared according to Example 1. One of HFC-134a (1.5 grams),
HFO-1243zf, HFO-1234ze(E), (1.5 grams) or HFO-1234yf (1.5 grams) is
added to the can to act as a propellant for the suspension. A
sample of 63 year old paper as described in Example 1 is sprayed
with the suspension from the aerosol can. The pH of the paper after
spraying is measured to be 9.0
Example 3
[0050] This example illustrates one method of deacidifying paper
according to the present invention.
[0051] One thousand (1000) grams of 1234ze(Z) are mixed with 3.2
grams of magnesium oxide and 0.8 grams of surfactant FC-740. The
mixture is placed in a 2 liter beaker which is kept at 0.degree. C.
and stirred. A cooling coil is placed on the lip of the beaker to
condense and recirculate 1233zd vapor. Four samples of 63 year old
paper are prepared and the acidity of each sample is measured using
the TAPPI509 om-96 method, a copy of a document describing this
method is attached hereto and is incorporated herein by reference.
The pH measurement of each sample is about 4.6. Each sample is
dipped in the mixture in the beaker for twenty seconds and allowed
to dry for 5 minutes. The solvent evaporates off very quickly. The
pH of each sample is then measured. The average pH of the four
samples is about 8.9
Example 4
[0052] This example illustrates another method of deacidifying
paper according to the present invention.
[0053] A 150 cc aerosol can is loaded with 50 grams of a suspension
prepared according to Example 3. One of HFC-134a (1.5 grams),
HFO-1243zf, HFO-1234ze(E) (1.5 grams) or HFO-1234yf (1.5 grams) is
added to the can to act as a propellant for the suspension. A
sample of 63 year old paper as described in Example 1 is sprayed
with the suspension from the aerosol can.
[0054] The pH of the paper after spraying is measured to be 9.0
Example 5
[0055] This example illustrates one method of deacidifying paper
according to the present invention.
[0056] One thousand (1000) grams of 1327cyc are mixed with 3.2
grams of magnesium oxide and 0.8 grams of surfactant FC-740. The
mixture is placed in a 2 liter beaker and stirred. A cooling coil
is placed on the lip of the beaker to condense and recirculate
1233zd vapor. Four samples of 63 year old paper are prepared and
the acidity of each sample is measured using the TAPPI509 om-96
method, a copy of a document describing this method is attached
hereto and is incorporated herein by reference. The pH measurement
of each sample is about 4.6. Each sample is dipped in the mixture
in the beaker for twenty seconds and allowed to dry for 5 minutes.
The solvent evaporates off very quickly. The pH of each sample is
then measured. The average pH of the four samples is about 8.9
Example 6
[0057] This example illustrates another method of deacidifying
paper according to the present invention.
[0058] A 150 cc aerosol can is loaded with 50 grams of a suspension
prepared according to Example 5. One of HFC-134a (1.5 grams),
HFO-1243zf, HFO-1234ze (E) (1.5 grams) or HFO-1234yf (1.5 grams) is
added to the can to act as a propellant for the suspension. A
sample of 63 year old paper as described in Example 1 is sprayed
with the suspension from the aerosol can. The pH of the paper after
spraying is measured to be 9.0
* * * * *