Note: Descriptions are shown in the official language in which they were submitted.
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PHOTOCATALYTIC PULP COMPOSITION, AND PROCESS FOR
PRODUCING AND PRODUCTS AND APPARATUS RELATING THERETO
BACKGROUND OF THE INVENTION
1. Field of the invention
The present invention relates to a photocatalytic pulp composition, a molding
material of which is mainly a pulp and/or a paper and a wastepaper, preferably
a
wastepaper of newspaper , and which has the photocatalytic activity and a
process and an
apparatus for producing the same, a photocatalytic pulp foam using the
photocatalytic pulp
composition and a process for producing the same, a molded article as a paper
and the like
having the photocatalytic pulp composition and a process for producing a
molded
photocatalytic pulp loam using the photocatalytic pulp foam and, more
particularly, it
provides a photocatalytic composition which can be widely applied to various
uses as a
furniture, a building material and a general packaging material such as a
filter material, a
paper sliding screen, a paper for a sliding screen, a wall paper, a blind, a
panel, a lamp
shade, a bed sheet, a curtain, a carpet, a sofa and a sheet, and a flexible
composite
packaging material, as well as a particular packaging material for, example,
antimold use,
an interior material for a car, a facing material ot~ an electric product for
house use, and a
raw material for and an article of various molded articles such as daily
necessaries, and a
lilm, a sheet, an adhesive or an adhesive resin layer, various coating agents
or a coating
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resin membrane, or a paint or a paint resin membrane, which has the
deodorizing and the
antibacterial properties and which can improve or effectively exert the
photocatalytic
properties of titanium oxide, that is, the properties of titanium oxide of
being activated by
an ultraviolet ray and oxidatively degrading organic materials, ammonia, NOx,
SOx and
the like such as the deodorizing and the antibacterial properties, by
adsorbing titanium
oxide onto a pulp and/or a paper or adding titanium oxide thereto, preferably
laminating a
wastepaper of newspaper which went through a DIP step, for example, in a paper
making
step, or laminating wastepapcrs obtained by separately drying wastepapers of
newspapers
via an adhesive, and articles for various uses.
2. Description of the Prior Art
The above kind of titanium oxide has been hitherto used as a deodorizing
filter
or provided as a coating agent, and used in order to obtain the stainproofing
or the
antibacterial properties of the surfaces by forming a film by coating on an
objective
material and drying it.
However, these previous articles lead to the disadvantageous results that the
reacting rate is slow or the completion of the reaction is remarkably late, in
the case of
articles obtained by coating titanium oxide or inserting and fixing titanium
oxide into gaps
between fibers.
A main object of the present invention is to provide a photocatalytic pulp
composition having the antibacterial, antimold, stainproofing and bad smell
degrading,
deodorizing and harmful material oxidatively degrading effects, and which is
widely used
for a packaging material, a building material, a filtering material and the
like, a
photocatalytic pulp composition which is effectively used for the air
treatment, the water
treatment and the soil treatment, and at the same time to provide a
photocatalytic pulp
composition having the photocatalytic properties which can improve the
photocatalytic
activity effects themselves of titanium oxide and a process and an apparatus
for producing
the same, a photocatalytic pulp foam using the photocatalytic pulp composition
and a
process for producing the same, and a process for producing a molded
photocatalytic pulp
using the photocatalytic pulp composition or a molded photocatalytic pulp foam
using the
photocatalytic pulp foam.
_p _
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SUMMARY OF THE INVENTION
In order to accomplish the above object, a photocatalytic pulp composition of
the
present invention is characterized in that 40 to 95 wt%, preferably 80 to 50
wt% of a pulp
and/or a paper having the water content of 3 wt% or less, the average fiber
diameter of 5
to 300 ~ m and the average fiber length of 0.1 to 70 mm is incorporated into 5
to 60 wt%,
preferably 20 to 50 wt% of titanium oxide (claim 1, claim 14).
Next, another photocatalytic pulp composition of the present invention can be
formed by incorporating 25 to 100 wt% of a thermoplastic resin therein
relative to the
total weight of titanium oxide, a pulp and/or a paper which are blended at the
above ratio
(claim 2).
By incorporating a thermoplastic resin therein, it becomes easy to heat-mold
the
above photocatalytic pulp composition and to mold it into the desired shape,
and the
thermoplastic resin serves as a binder and, thus, the binding between fibers
becomes firmer.
Next, a photocatalytic pulp foam is characterized in that a foaming agent
comprising
a) a solution of 0.01 to 0.07 wt% of a surfactant relative to 100 wt% of the
diluting
water,
b-1 ) not greater than 10 wt% of an amino acid and/or a protein such as
gelatin
comprising a keratinous substance obtained from a feather hair relative to 100
wt% of the
diluting water,
and/or
b-2) a bubble-like adhesive of 10 wt% of an adhesive relative to S to 50 wt%
of the
diluting water
is incorporated into the photocatalytic pulp composition in which the pulp
and/or the paper
are incorporated into titanium oxide (claim 3, claim 17).
Even when the adhesive is added thereto, in the case where the diluting water
is
50 wt% or more, the curing is difficult. In the case where the diluting water
is 5 wt% or
less, the viscosity is too high to expand.
Next, in the case where the protein (keratin or gelatin) is 10 wt% or more,
even
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when a temperature of the diluting water is 50 °C or higher, the
dissolution dose not
occur. When the surfactant is 0.01 wt% or less, the effects are not obtained,
while when
the surfactant is incorporated at 0.07 wt% or more, there is no difference in
the effects.
A process for producing the photocatalytic composition comprises a step of
Stlrl'Illg a mixture obtained by incorporating the above pulp and/or paper
into titanium
oxide at the above ratio by subjecting the stirring impact force thereto, to
cause the
shearing heat generation and, thereby, highly drying the above mixture with
this shearing
heat generation to reduce the water content to 3 wt% or less, a step of
swelling the pulp
and/or the paper upon drying to form a three dimensional entangled fibers, and
a treatment
step of pushing the titanium oxide towards the fiber surface of the pulp
and/or the paper
by the stirring impact force to fix it (claim 8).
Next, a process for producing of the photocatalytic pulp foam comprises a
treatment step of pushing the above titanium oxide of a mixture obtained by
incorporating
the pulp and/or the paper into titanium oxide at the above ratio towards the
fiber surface
of the above pulp and/or the paper according to the above step, to fix it to
obtain a
photocatalytic pulp composition, a foaming step of preparing an foaming agent,
and a step
of mixing this foaming agent into the above photocatalytic pulp composition
and
preferably mixing it to stir and, thereafter, pressing it to obtain a foam
having the diameter
of the particle size of 9 ,ec to 10 mm (Claim 10, claim 16).
A molded photocatalytic pulp and a molded photocatalytic pulp foam can be
prepared by pouring the above photocatalytic pulp composition or the
photocatalytic pulp
foam into a mold and, as necessary, compressing it into the desired shape, and
heating to
dl-v or drying the photocatalytic pulp foam (claim 11, claim 12).
Upon this, by molding by inserting an electric bulb or a tluorescent lamp as
an
inli-ared light source into this molded foam by the known means or surrounding
or
molding while leaving the source part with split-cavity mold, to obtain the
photocatalytic
activity effects at a place where the light source is not present, such as a
storehouse and a
rc 1 i~igcrator.
A blending ratio of a foaming agent in the photocatalytic pulp foam is such
that a
ratio of the foaming agent obtained by mixing into
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a) a solution containing 0.01 to 0.07 wt% of a surfactant relative to 100 wt%
of the
diluting water,
b-1) 0.05 to 2 wt% or less of gelatin and/or an amino acid relative to 100 wt%
of the
diluting water, and
b-2) 20 to 200 wt% of a bubble-like adhesive relative to 100 wt% of the
diluting water,
or
b-3) 20 to 200 wt% of a bubble-like adhesive relative to 100 wt% of the
diluting water
relative to the above pulp composition is 1:0.5 to 4, respectively (claim 14).
Alternatively,
a) the diluting water and the surfactant are blended as described above,
b-1 ) 0.1 to 10 wt% or less of gelatin and/or an amino acid is mixed with 100
wt% of the
above diluting water so that a ratio of the foaming agent and the pulp
composition is 1:0.5
to 3 (claim 19).
Furthermore, a molded photocatalytic pulp as a laminated photocatalytic pulp
paper can be obtained by laminating a virgin pulp or a wastepaper pulp
manufactured from
a wastepaper of newspaper, for example, after a DIP step on the above
photocatalytic pulp
composition.
The process for producing it is to make a paper from a virgin pulp or a
vV~astepaper in a step of making a paper after the above treatment step of
pushing and
fixing titanium oxide to form the laminated photocatalytic pulp paper.
Alternatively, in the case where the pulp is a paperboard-like dry pulp, the
process includes a splitting or disaggregating step by which the above dry
pulp is treated,
that is, the dry pulp is cut into a plurality of sections to be treated, and
the impact grinding
force is applied to the formed individual sections to obtain pulp fibers which
are ground
and wool-likely aggregated, have approximately the same length of a fiber-like
raw pulp
and have no fiber hair even with the grinding.
The above splitting and disaggregating step is accomplished by an apparatus
equipped with a fixation side impact grinding means which is positioned on a
fixed
circular disc, the center of which is penetrated through a port supplying
small cut sections
and in which respective fixing pins are successively provided on a plurality
of rotating loci,
a mobile side impact grinding means positioned on a mobile circular disc which
is
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opposite to the fixation circular disc and is rotatingly drivably provided and
in which
respective mobile pins ditTerent from the fixation pins are successively
provided on a
plurality of a rotating loci, and a take-out means for taking out fibrous
sections to be
treated which are ground and wool-likely aggregated into a take-out port.
Being configured as above, the present invention has the effect as described
below.
Thus, according to the present invention, a photocatalytic pulp composition
having the antibacterial, antimold, stainprooflng and stain and bad smell
degrading,
deodorizing, and harmful substance oxidatively degrading effects which can
remarkably
advance the reaction rate and the completion of the reaction, which can
improve the
photocatalytic activity effect of titanium oxide, and which can be applied to
many wide
uses such as a packaging material, a building material such as a wall paper, a
filter
material is provided. In addition, a photocatalytic pulp composition and its
foam which are
efTectively used in the air treatment, the water treatment and the soil
treatment can be
provided.
BRIEF DESCRIPTION OF DRAWINGS
The objects and advantages of the invention will become apparent from the
following detailed description of preferred embodiments thereof provided in
connection
with the accompanying drawings throughout which like numerals denote like
elements and
in which:
Fig. 1 is a view showing the surface of the photocatalytic pulp composition of
an
embodiment of the present invention measured by a scanning microscope. (A)
magnification X 200 and (B) magnification x 750;
Fig. 2 is a view showing the surface and the cross-section of the
photocatalytic
pulp composition of an embodiment of the present invention measured by a
scanning
microscope. (A) indicates the surface, magnification X 750, (B) indicates the
cross-section,
magnification X 200;
Fig. 3 is a partial cross-sectional view schematically showing the outlined
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construction of an impact grinding apparatus used in a step for splitting and
disaggregating
the present paperboard-like dry pulp;
Fig. 4 is a plane view of Fig. 3.;
Fig. 5 is a schematical front view for explaining the impact grinding action
in the
splitting and disaggregating step of Fig. 3.; and,
Fig. 6 is an outlined view showing an use example of the impact grinding means
used in the splitting and disaggregating step of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Example (1) for preparing a photocatalytic pulp composition
In this Example, a pulp and/or a paper used as a raw material includes not
only a
so-called virgin pulp in a paper making step but also a wastepaper pulp or a
pulp obtained
by mixing the both at 1:1, and the paper includes a normal paper and widely a
wastepaper
such as wastepaper oi~ newspaper.
A wastepaper which is ground with a cutter mill having 10 mm X 10 mm screen
and, thereafter, treated and which contains a large amount of a printing ink
is preferably
bleached or colored with a DIP treatment in a paper making step like a
wastepaper to be
laminated as described below.
And the average fiber diameter is 5 to 300 ,u m and the average fiber length
is
0.1 to 70 mm, and the bulk specific gravity is 0.005 to 0.04 in the case of
the paper fiber
and 0.24 in the case of the virgin pulp and/or paper. 80 wt% of it (upon this,
the pulp
and/or paper contains about 8 wt% of water) and 20 wt% of~ titanium oxide are
incorporated.
The average fiber diameter of the pulp and/or the paper of 5 to 300 ~ m, and
the
average fiber length of 0.1 to 70 mm means a particle size of 50% by weight in
accumulative weight percent of the pulp and/or the paper.
In the case of a paper, a paper is grinding-treated with a crusher and past
through
a screen having 10 mm mesh, which is used.
In addition, a printing ink in a wastepaper has no problem upon treatment
except
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that a product is slightly colored.
In the case of paperboard-like dry pulp, the dry pulp is cut into a plurality
of
sections, and the impact grinding force is applied to the formed individual
sections to
obtain pulp fibers which are ground and wool-likely aggregated, have
approximately the
same length of that of a fibrous raw pulp and have no fiber hair even with the
grinding.
Such the paperboard-like diy pulp after the splitting and disaggregating step
303 is used.
An impact grinding means used in this step is referred to as "separator" for
convenience in this Example.
In Figs. 3 to 6, a separator 130 is past and opened in a port 132 for
supplying
respective small sections to be treated in the center of a fixed circular disc
131, a fixed
end plate 133 is opposite to the fixed circular disc 131 separating by a
treating space 155,
respective circumferential edges of the fixed end plate 133 are fixed to the
fixed circular
disc 131 with a circumlerential side plate 135. A mobile circular disc 141
which is
rotated and driven by a rotating transverse axis 142 in the interior of the
treating space
155, the rotating transverse axis is supported pivotally by each bearing 143,
143. The
rotating transverse axis 142 is rotated and driven by a rotating driving means
such as a
motor and the like. And, on the fixed circular disc 131, a plurality (6 in
this Example) of
respective pins 134 are provided on rotating loci al to a6 (relative to a
mobile plate
141 ) (Fig. 5) on a concentric circle, and 16-24-32-36-40-42 of respective
fixing pins 134
are successively provided from the center of the fixed circular disc 131 on a
concentric
circle towards the circumfcrential edge in this Example. On the other hand, on
the mobile
circular disc 141, a plurality (6 in this Example) of mobile pins 144 which
are different
from the respective fixing pins 134 and positioned alternately on rotating
loci bl to b6 are
successively (4-4-4-4-4-6) provided on the concentric circle from the center
of the mobile
circular disc 141 towards the circumferential edge, and which are positioned
so that the
splitting and disaggregating action is obtained between respective fixed and
mobile pins
134, 144 by the impact grinding Force.
Further, a screen 1 S 1 having the predetermined mesh in which small pores
having
the desired diameter are formed by punching is circumferentially provided on
the
circumferential side of a mobile circular disc 141 between the circumferential
side plate
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135 separating by a discharge port 156, and a discharge port 152 is provided
below a
discharge space 156. A blower 157 is communicated with the discharge port 152
in a
separator 130 as shown in Fig. 6.
And, a discharge port 152 is communicated with a recovery tank 250 via a
discharge tube 239 provided with a blower 157.
In addition, as the screen 151, a screen having the diameter of about 0.8 mm
to
2.0 mm, though depending upon the rotation number of a mobile pin described
below is
used. Further, a take-out port 153 is formed on an lower part in the interior
of a screen
151 of a treating space 155 (Fig. 3). The grinding force which is applied to
small
sections to be treated is weakened by increasing the clearance between the
respective fixed
and mobile pins 134, 144 and the grinding force is strengthened by decreasing
the
clearance. A blower 157 which sucks air in a separator 130 is communicated
with the
take-out port 153 as shown in Fig. 6, and may be communicated with a supply
port 132
via this blower 157.
In addition, as shown in Fig. 3 and 6, the following construction may be
taken: A
take-out port 153 and a treating space 155 are communicated via a
communicating tube
235, the compressed air which is circulated in a treating space 155 ti-om a
take-out port
153 and which is from a compressed air supplying source (not shown) is
introduced in a
communicating tube 235 via a piping 236, and ground pulp fibers and alien
substances
which are discharged ti~om a take-out port 153 are circulated again in a
treating space 155
in a separator 130.
Alternatively, a ramiticating tube 237 communicating with a tank 240 for
recovering the pulp t3bers, or the pulp fibers and alien substances is
provided by branching
a supply port side of the communication tube 235, a two-directional valve 238
which can
be appropriately switched every set time, for example, with a timer circuit is
provided at a
ramiticating point of this ramilicating tube 237, the downstream side of the
communicating tube 235 is closed with a magnetic valve and the ramilicating
tube 237
side is opened, the pulp fibers which remain in a screen I51 are sucked and
recovered in a
recovery tank 240 via a ramiticating tube 237. Alternatively, a magnetic valve
which
opens and closes the ramiticating tube 237 and a magnetic valve which opens
and closes
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the downstream side of the ramiticating tube 235 are provided, and these two
magnetic
valves may be opened and closed alternately (Fig. 6).
By rotating a rotating transverse axis 142 with a rotating driving means such
as a
motor or the like to rotate a mobile circular disc 141 and supplying
respective small
sections to be treated in a supply port 132, the respective small sections to
be treated are
loosened into smaller fibers between respective fixed and mobile pins 134, 144
by the
impact grinding force in the center of the treating space 155 and, on the
other hand, the
diameter of the alien substances becomes about 2 to 6 mm in an indefinite
manner by the
impact grinding force. That is, respective small sections to be treated are
beaten and
ground or pulverized into small pieces with the impact by respective fixed and
mobile pins
133 and 144, and since the bending action is repeatedly applied to the
respective small
sections to be treated, the f finely-divided paperboard is separated from
small sections to be
treated. Like this, the pulp fibers and alien substances which constitute the
small sections
to be treated are separated every its kind, respectively, the boardpaper is
loosened into
libcrs and the alien substances are ground into tine pieces, respectively.
During this period, by an air stream produced by the compressed air which is
supplied in a treating space 155 by the centrifugal force by rotation of a
mobile circular
disc 141 or the suction force of a blower 157 or via a piping 236, the
separated and
liberized paper layer and pulp fibers or tiberized paper layer and a small
amount of alien
substances gradually approach the circumferential side of a circumferentially
provided
separator 130 of a screen 151 in the mixed state. Thereafter, the tiberized
pulp is past
through a screen 151 which is formed into meshes having the diameter of about
0.8 to 2
mm and discharged into a discharge space 156 and, thereafter, sucked towards
the outside
via a discharge port 152 and a blower 157, and recovered in a recovery tank
250 via a
discharge tube 239. On the other hand, the thin substance pieces and a small
amount of
pulp libers which are aggregated into a wool can not pass a screen 151 and
remain in the
treating space. When the recovery of the pulp fibers is completed, the alien
substances
which remain in the interior of a treating space 1 SS are discharged outwards
from a
take-out port 153.
The discharged substances are recovered into a recovery tank 240 via a
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ramif icating tube 237 by closing the downstream side of the communicating
tube 235 and
opening the ramilicating tube 237 side with a two-directional magnetic valve
238 of a
ramilicating tube 237 which is branched on the supply port side of the
communicating
tube 23 and which is communicated with a tank 240 for recovering the pulp
fibers to suck
the alien substances which remain in a screen 151.
In Fig. 3, the connection of a communication tube 235 to a ramilicating tube
237
is carried out via a flange 154 provided on a piping in which the upstream
side and the
take-out 153 side of a communication tube 235 are branched (towards a rear of
a paper
plane in Fig. 3).
The pulp fibers thus recovered are transferred to a next step.
Titanium oxide is effective when its particle size is smaller and, for
example, the
X-ray diameter of 7 to 50 nm can be used.
The pulp and/or the paper and titanium oxide, or these materials together with
synthetic fibers are placed, and the water content of titanium oxide and the
pulp and/or the
paper is adjusted to 3 wt%. preferably to 1 wt% or less by producing the
shearing heat
release by the shearing torce based on the stirring impact force by a stirring
impact wing
rotating at a high speed in a mixer to raise a temperature to about 120
°C . In this step,
water is evaporated from the pulp and/or the paper to dry it and at the same
time the pulp
andlor the paper in the case of a paper undergo the grinding action by the
impact force, is
swelled at the same time with the drying, the fibers become hairy and
aggregated into the
loosened wool to obtain three-dimensionally entangled fibers. Thereafter,
titanium oxide
is attached to or inserted in to 13x the fiber surface and the interior of the
fibers by the
stirring impact force by the stirring impact wing or the pushing external
force
accompanied with the shearing force.
The synthetic f fiber is preferable when the average fiber length is I to 100
mm,
the average diameter is l0 to 40 ,u m, and a melting point is 120 °C or
higher.
In addition, since a virgin pulp has usually the water content of 100 wt% or
more,
it is preferably pre-dried with the mixer or the known drier to the water
content of 10 wt%
or less before titanium oxide is mixed.
In this step, the attachment and fixation of titanium oxide are completed to
form
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"photocatalytic pulp composition".
In this step, the pulp and/or the paper in the raw material dose not become a
large
lump, are aggregated while loosened into dissociated wool without the mutual
firm
entanglement of the individual fibers and, in this sense, the three-
dimensionally entangled
fibers are formed and the individual pulp and/or paper are formed in such the
form that
titanium oxide is attached to all the surface of the fiber of the pulp and/or
the paper.
Since these individual are a loosened wool-like lump which is aggregated from
a paper,
there is no adhesive properties between the simple pulp and/or the paper and
the lump
itself has the high bulk sepcitic gravity. Therefore, the photocatalytic pulp
composition
formed by this step is a better material as a photocatalytic pulp composition
which can be
made into a paper in various known paper making steps.
The above step is described in more detail. Since the water content of the
pulp
and/or the paper is 3 wt% or less, the interface between titanium oxide and
the pulp and/or
the paper is lost, titanium oxide is dispersed into the pulp and/or the paper
at a uniform
density, titanium oxide becomes easy to be absorbed onto or attach to the pulp
and/or the
paper and at the same time the pulp and/or the paper is mixed and dispersed
while
completely surrounding the circumference of the pulp and/or the paper.
As such, the present photocatalytic pulp composition can be used as a raw
material to form a paper by various paper making methods.
In addition, a plastic fiber or glue, starch, wax or a resin adhesive such as
vinyl
acetate and acryl system can be mixed therein in a paper making step to
prepare a molded
photocatalytic pulp composition.
A photocatalytic pulp paper was prepared using the above pulp composition
having the photocatalytic activity.
As Examples and Comparative Examples of a photocatalytic pulp composition
using a photocatalytic pulp composition, titanium oxide ST-O1 (manufactured by
Ishiharatechno Company) having the X ray diameter of 7 nm, the titanium oxide
content
of 90 wt% or more and the specific area of 300 m'-Ig was used to treat with
the stirring
impact force by a stirring impact wing rotating at a high speed in the mixer.
An internal temperature of a mixer: 120°C
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[ I'hotocatalytic pulp composition: Example 1 ]
Loosened wool-like pulp; 2 kg (50 wt%), the water content 10 wt%,
titanium oxide; 2 kg (50 wt%), the water content after treatment ; 0.5 wt%
About 2.5 kg of a plate-like dry pulp is treated in the splitting and
disaggregating
step to obtain about 2.0 kg of loosened wool-like pulp, and about 2.0 kg
titanium oxide is
f ixcd to obtain about 3.90 kg of a photocatalytic pulp composition.
[I'hotocatalytic pulp composition; Example 2] [Fig. 1 and Fig. 2]
Loosened wool-like pulp 2 kg (80 wt%), the water content 10 wt%
Titanium oxide; 0.5 kg (20 wt%)
The water content afiter treatment; 0.6 wt%
Paper fiber 2 kg (80 wt%), the water content 10 wt%; Treated in the splitting
and
disaggregating step.
Titanium oxide; 0.5 kg (20 wt%)
This was treated via a fiixation treating step to obtain about 2.3 kg of a
photocatalytic pulp composition.
The photocatalytic pulp compositions obtained in the above Examples 1 and 2
were used to make a paper according to the same step as that of manual
Japanese paper
making step (For convenience, referred to as Test Examples 1 and 2). 500 ml of
water
was added to 20 g ofi~ the photocatalytic pulp composition, stirred for 15
minutes, 2 liter of
water was added thereto to make a paper which was dried naturally. The
thickness of a
paper was 0.25 mm (Fig. 2)
Using the photocatalytic pulp composition obtained in the above [Example 1],
the
composition was diluted to the pulp concentration of 8 wt% to perform the
beating
treatment with a beater for 1 hour.
On the other hand, a beaten pulp raw material such as a virgin pulp including
a
.lapanese paper, herein for example, a wastepaper pulp comprising a wastepaper
of
newspaper after a DIP step (de-inking treatment) was diluted with water to the
pulp
concentration of 8 wt%, beat-treated for 1 hours, then a wet sheet ol~ a pulp
comprising a
photocatalytic pulp and a wastepaper ofi~ newspaper is made into a paper using
a paper
making machine in the known paper making step. A photocatalytic pulp (50 g/m'
) and a
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pulp comprising a wastepaper of newspaper ( 10 g/m ~ ) after beating treatment
were made
into a paper using a wire paper machine and a cylinder paper machine,
respectively, which
were overlapped, transferred to a press part and further dried to make a
paper.
By the foregoing, a transparent, air-permeable white substrate layer was
laminated
on a photocatalytic pulp layer (Example 3).
Example 4
The photocatalytic pulp composition obtained in [Example 2] and a wastepaper
of
newspaper were made into a paper as in Example 1.
Beater treatment time 1 hour
Concentration of photocatalytic pulp 8 wt%
Concentration of a wastepaper of~ newspaper pulp 8 wt%
Basis weight Total 60g/m 'i
Photocatalytic pulp layer 50 g/m -
Newspaper wastepaper pulp layer 10 g/m ~'
[Photocatalytic pulp + paper; Comparative Example]
Paper fibers; 2 kg (80 wt%) and titanium oxide; 0.5 kg (20 wt%) were diluted
to
the pulp concentration of 8 wt% with a beater without using a mixer in the
above
embodiment and Example, to make a paper. Basis weight Total 50 g/m ~'
The test results of the above Test Examples 1 and 2 and Comparative Example 1
arc shown below.
rl'est conditions
Concentration of added acetaldehyde about 820 ppm
Light intensity about 1 mW/cm'-
Reaction vessel 1 liter
Photocatalytic pulp composition and other Comparative Example
Sample size 8 X 8 em Thickness: 0.25 mm
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Table 1
Photocatalyst Co ~= Co ~ Acetaldehyde
Co= initial production production initial
producing rate rate vanishing
speed at 1 h at 2 h speed
ppm/min (%) (%) (ppm/min)
Test Ex. 1 29.8 79 100 18.9
'lest Ex. 2 24.0 68 100 17.5
Comp. Ex. I I 1.0 38 47 7.4
The photocatalytic Co _ initial producing rate is obtained by the following
formula;
(Apparent Co~_ initial producing rate) - (light control Co~~ producing rate)
Acetaldehyde initial vanishing rate is the vanishing rate at 30 min. after
photo-irradiating.
The production rate (%) at 1 h or 2h is a ratio of the production relative to
theoretical value and was calculated by only photocatalyst portion.
The initial acetaldehyde vanishing rate (%) is concentration at I h/initial
concentration X 100.
The photocatalyst + pulp paper; a paper of Comparative Example 1 has the
extremely low photocatalytic activity and the acetaldehyde vanishing rate is
slow.
To the contrary, the photocatalytic pulp composition Test Example 1 shows 100
of Co~~ production rate at 2h like Test Example 2, and it can be seen that
after the
concentration of acetaldehyde is decreased, the sufficient reaction occurs.
It was seen that simple mixing of titanium oxide can not afford the effects
and
the present invention extremely can improve the photocatalytic activity.
Digs. 1 (A) and (13) and I~igs. 2 (A) and (B) show scanning microscopic
photographs of the photocatalytic pulp composition and photocatalytic pulp
composition
- 15 -
CA 02281428 1999-09-03
('Pest f?xample 2) oi~ Example 2, respectively, it can be seen that titanium
oxide is attached
and connected to the external face of a pulp raw material and the state where
titanium
oxide is attached is maintained on the external face of a pulp and also in the
interior of a
paper even according to a paper making method using water. This is also clear
from the
fact that little titanium oxide is dissolved in water which was added at a
point of stirring
in a paper making experiment of Test Example.
In addition, the above Examples 3 and 4 afforded the similar results to those
of
Test Examples 1 and 2 (Examples 1 and 2).
[Example (2) for preparing a photocatalytic pulp composition]
In this Example, a ratio of blending titanium oxide, a pulp and/or a paper
which
forms a photocatalytic pulp composition are the same as those of the above
Example (1)
for preparation.
In addition, the same titanium oxide, the pulp and/or the paper as those of
Preparation Example ( 1 ) can be used as a raw material.
In this Example, as in the Preparation Example (1), titanium oxide and a pulp
and/or a paper are blended and at the same time 25 to 100 wt% of a
thermoplastic resin is
added to the total weight of the titanium oxide and pulp and/or paper to form
a
photocatalytic pulp composition.
The photocatalytic pulp composition is formed, and a recycled paper comprising
a
wastepaper pulp obtained by DIP-treating a wastepaper of newspaper can be
laminated on
the composition.
As this thermoplastic resin, various resins can be used. In addition, a
thermoplastic resin in the powder, particle and sheet forms can be used.
Preferably, a
thermoplastic resin having a particle size of 1 mm or less in the case of a
powdery or
particulate thermoplastic resin , or a thermoplastic resin having the
thickness of 1 mm or
less in the case of a sheet-like thermoplastic resin is ground into pieces
having the side of
mm or less to use it.
When the produced photocatalytic composition is heated to form a molded
photocatalytic pulp, if heated at a high temperature, a pulp in this
photocatalytic pulp
composition is burnt by this heat in some cases and, therefore, it is
preferable that a
_m _
CA 02281428 1999-09-03
thermoplastic resin having a lower melting point such as PE (LLD; linear low
density) and
vinyl acetate is used as compared with a thermoplastic resin having a
relatively high
melting point such as polyester, polycarbon and the like.
A pulp and/or a paper and a thermoplastic resin which constitute the
photocatalytic pulp are not required to place in a mixer as a separate raw
material and, for
example, a composite t1I111 having a paper layer laminated with a
thermoplastic resin film
and which is used for a milk pack is ground into small pieces having the side
of around
mm and, thereafter, the pieces may be placed in the mixer as described above.
In this
cane, a paper layer of the composite film becomes a pulp fiber which
constitutes a
photocatalytic pulp composition and a thermoplastic resin layer becomes a
thermoplastic
resin which constitutes the Formed photocatalytic pulp composition to be
formed.
Therefore, an amount of titanium oxide to be blended is determined taking a
ratio of a
pulp component relative to a thermoplastic resin component contained in a
composite film
into consideration and at the same time, as necessary, a thermoplastic resin
and/or a pulp
and/or a paper are added so as to adjust a ratio of respective raw materials
to the
aforementioned ratio.
After the pulp and/or the paper and titanium oxide and the thermoplastic resin
are
placed in a mixer, the mixer is actuated to produce the shearing heat by the
shearing force
based on the stin-ing impact Force by a stirring impact wing which rotates at
a high speed
in the mixer and a temperature is raised to about 120 °C to adjust the
water content of the
pulp and/or the paper to 3 wt%, preferably 1 wt% or less. In this step, water
is
evaporated from the pulp andlor the paper to dry it and, at the same time, the
pulp and/or
the paper in the case of a paper undergoes the grinding action by the impact
force to
become fibrous and, further, which is swelled accompanied with the drying,
fibers are
scuffed up and aggregated into a loosened wool to form three-dimensionally
entangled
fibers. Thereafter, titanium oxide is attached to or inserted into to fix the
surface of the
fibers or also the interior of the fibers by the pushing external force
accompanied with the
stirring impact force or the shearing force by the stirring impact wing.
In addition, at the same time, at least a part of a thermoplastic resin placed
into a
mixer also undergoes the grinding action, and are ground into small pieces
which are
CA 02281428 1999-09-03
attached to or inserted into to fix the surface of the fibers and the interior
of the fibers by
the pushing force accompanied with the stirring impact force or the shearing
force by the
stirring impact wing like the aforementioned titanium oxide.
When a composite film such as a milk pack is used as the aforementioned pulp
and/or the paper and thermoplastic resin, small sections of the composite film
placed into a
mixer are separated into a thermoplastic resin layer and a paper layer by the
stirring
impact force by the shearing impact wing and the separated paper layer is
ground by the
stirring impact force and loosened into fibers as described above for the
paper.
1n addition, at least a part of a thermoplastic resin layer is also ground
into small
pieces by the stirring impact force and attached to or inserted into to tix
the surface of the
pulp fibers and the interior of the pulp fibers like the aforementioned
separately placed
thermoplastic resin.
In addition, a thermoplastic resin is not required to melt by the heat upon
stirring
with a mixer as long as it is attached to or inserted into to fix the pulp
fibers.
The present photocatalytic pulp composition can be easily formed into a molded
photocatalytic pulp such as a press sheet and the like, for example, by
pressing under
heating. In addition, since the molded article which was formed by the method
binds
firmly between pulp fibers because a thermoplastic resin attached to or
inserted in to fx
the surface or the interior of the pulp fibers serves as a binder, it becomes
a molded article
such as a tough press sheet and the like.
A pulp composition having the photocatalytic activity obtained by the
aforementioned Preparation Example was used to manufacture a molded,
photocatalytic
pulp composition(press sheet).
IJxample and Comparative Example of a photocatalytic pulp paper using a
photocatalytic
pulp composition
As an Example, a thermoplastic resin PE [Urdozex 4030P (powder): Mitsui
Petroleum chemichal Industries Co., Ltd.] was used and the other raw materials
are the
same as those of the aforementioned Example 2.
[I'hotocatalytic pulp composition; Example 5: Test Example 3]
Paper fiber; 2 kg (80 wt%), the water content 10 wt%
_n _
CA 02281428 1999-09-03
Titanium oxide; 0.5 kg (20 wt%)
Thermoplastic resin: PE 1.5 kg (Paper fiber + 60 wt% relative to the total
weight
of titanium oxide)
The water content atter treatment: 0.5 wt%
The above raw material is placed into a mixer and stirred, and a temperature
is
raised to about 120 °C to adjust the water content of the paper fiber
to 3 wt%, preferably
1 wt% or less.
2.27 g of the photocatalytic pulp composition obtained as described above was
spread 8 X 8 cm, nipped with a Teflon sheet, and heated in a thermostatic
chamber at 150
°C for 2 hours while applying a load of 1 kg to form a molded
photocatalytic pulp (press
sheet) having the basis weight of 50 glm ~'' which was used as a sample (Test
Example 3).
Example 6
The molded press sheet of the aforementioned Example 5 and a wastepaper pulp
comprising a wastepaper of newspaper after a DIP step (deinking treatment)
were made
into a paper to diy. The basis weight I 0 g/m ~' was laminated on one side via
an adhesive
with hot press, which was used as a sample (Example 6).
Beater treatment time 1 hour
Concentration of photocatalytic pulp 8 wt%
A photocatalytic pulp was not treated with a beater.
Basis weight Total 60 g/m-
Photocatalytic pulp layer 50 g/m
Newspaper wastepaper pulp layer 10 g/m
[Comparative Example 2 (The aforementioned photocatalytic pulp paper; Test
Example 2)]
Paper fiber; 2 kg (80 wt%), the water content 10 wt%
Titanium oxide; 0.5 kg (20 wt%)
The water content after treatment; 0.6 wt%
The photocatalytic pulp composition obtained in the aforementioned Example 2
was used and made into a paper according to the same step as that of manual
Japanese
paper step (Unfoamed: the aforementioned Test Example 2).
500 ml of water was added to 20 g of the photocatalytic pulp composition,
stirred
lg _
CA 02281428 1999-09-03
for 15 minutes, 2 liter of water was further added and made into a paper which
was
naturally dried. Weight: 1.42 g and the paper thickness: 0 25 mm were
Comparative
Example 2.
Comparative Example 3 (L;xample 7)
The photocatalytic pulp composition obtained in the aforementioned Example 2
was used and made into a paper according to the same step of the Comparative
Example 1
(basis weight, total 50 g/m - ), a wastepaper pulp comprising a wastepaper of
newspaper
after a DIP step (deinking step) and this molded photocatalytic pulp were made
into a
paper to dry (basis weight, total 60 g/m ~' ), which was laminated one side
via an adhesive
with a hot press.
Beater treatment time 1 hour
Concentration of photocatalytic pulp 8 wt%
Concentration of wastepaper of newspaper 8 wt%
Basis weight Total 60 g/m ~''
Photocatalytic pulp layer 50 g/m-
Newspaper wastepaper pulp layer 10 g/m ~'
The results comparing the molded photocatalytic pulp of the aforementioned
Example 5 and Comparative Example 2 under the following conditions are shown
in Table
Experimental conditions
Concentration of added acetaldehyde about 820 ppm
Light intensity about 1 mmW/cm ~-
Reaction vessel 1 liter
Photocatalytic pulp paper and other Comparative Example
Sample size: 8 X 8 cm Basis weight Total 60 g/m ~y
- 20 -
CA 02281428 1999-09-03
Table 2
Photocatalyst Co ~ Co ~ AcetaldehydeCo z
Co ~ initial production production initial 100%
producing rate rate vanishing production
rate at 1 h at 2 h rate time
ppm/min (%) (%) (ppm/min.) time (h)
~l'est 24.3 70 100 16.2 2
Ex. 3
C'om. 24.0 68 100 17.5 2
Ex. 2
It was contirmcd that the molded photocatalytic pulp (press sheet; Test
Example
3 ) formed from the photocatalytic pulp composition manufactured in Example 5
has
approximately the same properties as those of the photocatalytic pulp paper
(Comparative
Example 2) obtained in the aforementioned Test
Example 2.
Therefore, it was revealed that the molded photocatalytic pulp of the
alorcmentioned Test Example 3 has the effect of improving the photocatalytic
activity
ef~f iciency which can not be obtained by simply mixing titanium oxide.
In addition, since CO _ production rate at 2 hours is 100%, the sufficient
reaction
occurs even after the concentration of acetaldehyde is decreased.
In addition, Example 6 (Test Example 3) and Comparative Example 3 (Example
7) afforded the similar results to those of Example 5 and Comparative Example
2,
respectively.
[Preparation Example of a photocatalytic pulp foam]
The present photocatalytic foam is obtained by expanding the photocatalytic
pulp
composition manufactured by the aforementioned Preparation Example ( 1 ).
Since
Preparation Example of the photocatalytic pulp composition is the same as
Preparation
Example ( 1 ), a step of expanding the photocatalytic pulp composition with a
foaming
agent is explained below.
-21 -
CA 02281428 1999-09-03
A foaming agent used herein comprises water for dilution, a surfactant, an
adhesive and an amino acid or gelatin.
The surfactant to be used is not limited to but includes a non-ionic ether
type
such as polyoxyethylene lauryl ether, polyoxyethylenoley ether and
polyethylene glycol
nonyl phenyl ether, amino ether type and ether ester type, and an anionic
surfactant such
as a salt of resinic acid, lignin sulfonic acid, ABS and a salt of lauryl
alcohol sulfate ester.
Gelatin particle used herein is preferably obtained by hydrolyzing a protein
derived from collagen such as commercially available gelatin and the like with
an enzyme
acid or an alkali to obtain a polypeptide which is used as a raw material and
this
polypeptide is ground according to a dry grinding method such as a jet mill
and the like
and, for example, gelatin having the average molecular weight of 8,500 or less
is used as a
raw material for grinding.
Particularly preferably, a crude powder of gelatin having the average
molecular
weight of 1,000 to 8,500 obtained by hydrolyzing a commercially available
gelatin with an
enzyme, an acid or an alkali and spraying in a hot air at approximately 120
°C through a
nozzle to diy is used.
Then, an amino acid particle used in this Example is explained.
An amino acid (crude powder) used herein is positioned on an extension line of
a
gelatin particle, is extremely resembles a gelatin particle, and is not
limited to but includes
amino acids having the average molecular weight of 100 to 200 and having no
polypeptide
linkage obtained by hydrolyzing a protein contained in defatted soybean, wheat
protein,
peanut oil bath, rapeseed grounds, cotton seed grounds, corn, cow's milk,
white of an egg,
fish meat and the like, keratin contained in hair, wool and the like with an
enzyme, an
acid or an alkali.
The aforementioned keratin is contained in a feather, and a hair and a nail of
animals and they can be used alone or a combination of them. A nail is
desirably
subjected to a grinding step as a pretreatment. Therefore, it is preferred
that a feather is
used as a raw material because the step can be omitted. In order to convert a
feather into
a slurry, water is added to the feather, which is boiled with an indirect heat-
type heat
exchanger at 70 to 120 °C for 3 to 5 hours under the normal pressure or
under pressure.
- 22 -
CA 02281428 1999-09-03
An amount of water to be added is not limited to specific ones as long as it
is an
amount required to convert a feather into a slurry. 'l'he amount may be 50 to
80 parts (by
weight ) of water relative to 100 parts of a feather.
The feather thus boiled is filtered together with water.
For example, the feather which became a slurry and a boiling and aging
solution
are placed into a filtering apparatus having a cloth of mesh 100 m as a filter
and 60 parts
of an aqueous (~ -keratin solution relative to 100 parts of a feather is
recovered. The
remaining 40 parts are discarded.
Then, the amino acid particle can be used by blending into a resin together
with
the aforementioned gelatin particle or in place of the aforementioned gelatin
particle. The
amino acid particle used herein can be prepared by grinding the crude powder
of an amino
acid having the average molecular weight of 100 to 200 obtained by hydrolyzing
various
proteins with an enzyme, an acid or an alkali. For example, in the ground
amino acid
particle obtained by placing a crude powder of an amino acid together with
dimethylformamide into a ball mill, in compared with a gelatin particle
obtained by the
similar grinding to a crude powder o an amino acid, the excessively grounded
particle and
ungrounded particle are slightly present together and the amino acid particles
are in the
state where they are made homogenous in a uniform particle size, which causes
no
practical problem. In addition, the amino acid particle obtained by grinding
while
classiFying the crude powder of amino acid using a dry grinding means such as
a jet mill
and the like is further made homogenous into a uniform particle size and is
practically
suitable.
Therefore, the composition of an amino acid in the crude powder of an amino
acid used herein is different depending upon a raw material from which the
crude powder
of an amino acid is obtained but an amino acid particle obtained by grinding
the crude
powder of an amino acid having any composition of an amino acid can be
practically used.
Next, the aforementioned adhesive can be formed of glue and starch which are
used as the aforementioned binder and, in addition, a resin normally used for
an adhesive
and, if desired, may be a layer containing an additive such as an adhesiveness
subjecting
agent, a softening agent, a tiller, an aging preventing agent, a cross-linking
agent and the
- 23 -
CA 02281428 1999-09-03
like.
As a resin, for example, there are a natural rubber; a synthetic rubber such
as
styrene-butadiene system, polyisobutylene system, isoprene system; acrylic
resin, for
example, methyl (meth)actylate, ethyl (methyl)acrylate, butyl (meth)acrylate,
2-ethylhexyl
(meth)acrylate; olefin resin, for example, polyethylene, polypropylene;
silicone resin, for
example, siloxane~trichlorosilane, alkoxysilane; urethane resin, for example,
polyesterpolyol, polycarbonate, polyetherpolyol, polyalkylenepolyol and the
like.
Preferably, an emulsion adhesive, for example, an urethane emulsion or an
acrylic
emulsion adhesive, for example, a polyester polyurethane aqueous dispersion
two-part
curing type adhesive is used.
For example, as an urethane emulsion, an urethane emulsion (trade name WA351,
manufactured by Dainichi Seikakogyo (K.K.)) to which a cross-linking aid such
as the
known melamine resin and the like or a curing agent such as isocyanate, or an
additive for
stabilizing the mechanical strength is used.
The blending ratio of a foaming agent in the photocatalytic pulp foam is as
hollows:
Table 3
Ivoaming agent mixing ratio
Foaming agent Dilution water Surfactant Amino acid/gelatin Adhesive
A 100 0.01 ~-0.07 (l.l ~-10
Q 100 0.01 ~-0.07 20~-200
C 100 0.01 ~-0.07 0.05~-2 20~200
The mixing ratio of a photocatalytic pulp composition and the foaming agent is
as
follows relative to 100 (wt%) of the photocatalytic pulp composition.
_ z,~ _
CA 02281428 1999-09-03
Table 4
Kind of foaming agent Foaming agent(wt%)
A 50300
B 50 ~' 400
C 50~-400
Then, these foaming agents, preferably together with a photocatalytic pulp
composition are mixed and stirred at the aforementioned blending ratio with a
blending
machine. This mixing and stirring is carried out in order to mix air bubbles
into the
foaming agent to convert into a l7owing bubble of the predetermined particle
shape.
By converting into a bubble-like foam, the surface area is increased, the
photocatalytic activity ef~Fect is enhanced, and the concentration of a
foaming agent can be
adjusted to mold it thinly and uniformly. Further, the long-term holding of
the bubbles
can be maintained by an additive such as gelatin and molding as a foam is
easy. In
addition, mutual adhesion of~ pulp fibers can be performed firmly in place of
an adhesive.
An aqueous solution of this mixed and stirred bubble layer scum is immediately
placed in a foaming machine comprising a pressure vessel of gauze pressure of
8 kg/cm~'.
r1'he pressure of the foaming machine is controlled to the gauze pressure of 8
kg/cm',
and a discharge port of a tank is equipped with a foaming part which
accommodates
ceramic beads having the diameter of~ 0.5 mm tightly under pressure, and the
foaming
machine produces approximately uniform bubbles having the particle diameter of
9 mm
and having the suitable viscosity through the discharge port by pressurizing
for about 30
seconds.
In addition, after this foaming step, or at the same time with preparation of
the
aforementioned photocatalytic pulp composition, a synthetic fiber having the
average fiber
length of 1 to 100 mm, the average diameter of 10 to 40 ~ m and a melting
point of 120
'C or higher may be blended, mixed and dispersed.
The blending ratio of the synthetic fiber is desirably maximum 9 relative to 1
of
- 25 -
CA 02281428 1999-09-03
the atorementioned photocatalytic pulp composition.
[Molded photocatalytic pulp foam; Example 8]
Although the aforementioned photocatalytic pulp foam and a molded
photocatalytic pulp
herein can be formed by various molding methods, for example, transfer,
rotation molding,
calendar, lining processing, slash, dip molding, lamination molding and the
like, a molded
photocatalytic pulp or a molded photocatalytic pulp Loam can be obtained in
any form
including a paper-like foam for use as a filter and the like by coating with
various coating
methods, or laminating, or spraying with a spraying gun, on the surface of a
timber, a
paper, a nonwoven cloth or other substrate or on a release paper, or pouring
into a mold
for casting molding, or molding by various molding methods such as molding by
omitting
or alleviating the heating in air-press forming or compression molding, then
as necessary,
dying or heating to dry. Here, an embodiment using spraying coating with a
spray gun is
shown.
I'hotocatalytic pulp composition (The aforementioned Example 2)
Paper fiber; 2 kg (80 vV~t%), the water content 10 wt%
Titanium oxide; 0.5 kg (20 wt%)
Water content after treatment; 0.6 wt%
After the aforementioned photocatalytic pulp composition was mixed with the
following foaming agent:
Surfactant; 1.25 kg
Dilution water; 2.5 kg
Gelatin; 2.5 kg,
to expand, which was coated on a wooden plate at the thickness of 5 mm with a
spray gun, dried at 100 °C for 3 hours to obtain a sheet-like molded
foam having the
weight of 0.27g and the thickness of 1 mm.
('Pest Example 4)
[Comparative Example 3 (The aforementioned photocatalytic pulp paper; Test
Example 2)]
Paper fiber; 2 kg (80 wt%), Water content 10 wt%
Titanium oxide; 0.5 kg (20 wt%)
Water content after treatment; 0.6 wt%
- 2 (i -
CA 02281428 1999-09-03
The photocatalytic pulp composition obtained in the aforementioned Example 2
was used and made into a paper according to the same step as manual paper
making step
(unfoamed: Test Example 2).
500 ml of water was added to 20 g of a photocatalytic pulp composition, the
mixture was stirred for 15 minutes, 2 liter of water was further added and
made into a
paper to naturally dry. Weight: 1.42 g and the thickness: 0.25 mm was
Comparative
Example 3.
Comparative Example 4]
In Comparative Example 4, a glass plate was dipped into a solution obtained by
adding a solvent to 10 wt% of a silica binder and 10 wt% of titanium oxide to
obtain a
dried sample of 50 wt% of a silica binder and 50 wt'% of titanium oxide.
The test results of the aforementioned Test Example and Comparative Example
arc shown below.
Experimental conditions
Concentration of added acetaldehyde about 820 ppm
Light intensity about 1 mW/cm-
Reaction vessel 1 liter
Photocatalytic pulp composition paper and other Comparative Example
Sample size: 8 X 8 cm Thickness: 0.25 mm
'fable 5
PhotocatalystCo~ Co: Acetaldehyde Coz
Co ~ initialproduction production initial 100%
producing rate rate vanishing production
rate at 1 h at 2 h rate time
ppm/min (%) (%) (ppm/min.) time (h)
~I'cst Ex. 4 7.0 32 46 6.2 7
C:om. Ex. 3 24.0 68 100 17.5 2
Com. Ex. 4 11.5 - 50 10.4 20
- 27 -
CA 02281428 1999-09-03
A Test Example 4: photocatalytic pulp foam has not greater than one fifth of
the
weight of the composition except for a foaming agent component as compared
with that of
C omparative Example 3 (Photocatalytic pulp paper: Test Example 2) and, thus,
respective
values in the test results should be not greater than one fifth as compared
with
Comparative Example 3 but the molded photocatalytic pulp foam shows respective
values
not smaller than one t7tth as compared with Comparative Example 3.
By using the afor ementioned molded photocatalytic pulp or the molded
photocatalytic pulp foam as an inner, external or intermediate layer or as a
laminating
material such as a core material or a substrate, the pulp or the pulp foam can
be made into
a laminated article in which a normal paper, a synthetic paper, a plastic
film, or a
nonwoven cloth are laminated in two or three layers. In this case, by using,
as a core
material or a substrate, materials having the excellent transparency such as a
normal paper,
a synthetic paper, a nonwoven cloth or a woven cloth, which has the
transparency or has
many openings, a nonwoven cloth having the low density, a woven cloth having
the crude
weave pattern, or a transparent tilm, not only when the molded photocatalytic
pulp or the
photocatalytic pulp foam is arranged in the state where it is positioned at
the light source
side and can be directly exposed to the light but also when the photocatalytic
pulp is not
positioned directly on the light source side such as when the molded
photocatalytic pulp or
the photocatalytic pulp foam is held between the core materials or the
substrates, the
molded photocatalytic pulp or the photocatalytic pulp foam is irradiated with
the light
which is past through the core material or the substrate and suitably exerts
the
photocatalytic properties of titanium oxide and, at the same time, by using a
core material
or a substrate equipped with openings and having the air permeability, the
molded
photocatalytic pulp can be easily used as a filter and the like.
The aforementioned molded and foamed articles are excellent in the air
permeability and best for use as a filter. In addition, in the foamed
articles, drying of an
adhesive is promoted upon molding. In addition, in the case of a molded
article obtained
by heating to mold a photocatalytic pulp composition with a thermoplastic
resin blended
therein, the thermoplastic resin serves as a binder and, thereby, binding
between pulp
fibers becomes firm and a tough press sheet and the like can be obtained.
- 28 -
CA 02281428 1999-09-03
Now, that the invention has been described. Thus, the broadest claims that
follow are not directed to a machine that is configure in a specific way.
Instead, said
broadest claims are intended to protect the heart or essence of this
breakthrough invention.
This invention is clearly new and useful. Moreover, it was not obvious to
those
01~ ordinary skill in the ac-t at the time it was made, in view of the prior
art when
considered as a whole.
Moreover, in view of the revolutionary nature of this invention, it is clearly
a
pioneering invention. As such, the claims that follow are entitled to very
broad
interpretation so as to protect the heart of this invention, as a matter of
law.
It will thus be seen that the objects set forth above, and those made apparent
from
the foregoing description, are eiliciently attained and since certain changes
may be made
in the above construction without departing from the scope of the invention,
it is intended
that all matters contained in the foregoing description or shown in the
accompanying
drawings shall be interpreted as illustrative and not in a limiting sense.
It is also to be understood that the following claims are intended to cover
all of the
generic and specific features of the invention herein described, and all
statements of the
scope of the invention which, as a matter of language, might be said to fall
thcrebetween.
?g _
