Technical Field
[0001] This invention relates to a package for liquid containers, e.g., blood bags, and
more particularly, to a liquid container package, which can prevent moisture condensation
from forming inside the package.
Background Art
[0002] Heretofore, for preserving blood bags it has been the practice to lay Japanese paper
as a water absorption sheet beneath the blood bags to absorb the condensed water droplets.
The blood bag is made of a soft plastic material permeable by water vapor. Water vapor
penetrates the blood bag as condensed moisture inside a sealed container package due
to, for example, a difference in temperature between the sealed container package
and the environment. The amount of condensed water can be much as 8 to 10 cc in the
case of a single container package, in which five sets of 200-cc blood bags (a total
blood content amounting 140 cc) are sealed. Heretofore, Japanese paper has been used
by laying it beneath the bottom of the blood bag to absorb the condensed moisture.
Japanese paper, however, has a poor water absorption property and can not absorb water
unless it is contacted by water, that is, it can not absorb water in the state of
vapor, and it is only when this vapor condenses, that the paper is sufficiently able
to absorb water.
[0003] Further, the Japanese paper lacks a water-retaining capacity, i.e., it lacks an absorbent
quality. Therefore, water once absorbed by the paper can readily dissipate due to
a temperature rise or like cause. Therefore, an over-saturation state is produced
inside the blood bag, and evaporation, dissipation, and condensation of water repeatedly
take place. Further, the surface of the blood bag which is not in contact with Japanese
paper has no ability what so ever to absorb water. Therefore, affixing labels indicating
the blood type and other data to the bags is difficult due to the moisture which collects
on the surface of the blood bags when collecting blood. Further, a label once applied
is liable to fall off. There is a further problem in that water that has not been
absorbed by the Japanese paper beneath the blood bags in the package may be mistaken
as leakage of the blood bag content.
Disclosure of the Invention
[0004] An object of the invention is to provide a liquid container package, which can maintain
an adequate humidity therein and which can also prevent moisture from condensing on
the inside of the bag.
[0005] To attain the above object of the invention, there is provided a liquid container
package, which comprises a liquid container having a wall permeable to water vapor
and containing a liquid, a package for hermetically wrapping one or more of said liquid
containers and a humidity control member disposed between said liquid container or
containers and said package and comprised of a water- and water vapor-permeable sheet
and resinous material enclosed by said water- and water vapor-permeable sheet and
having a water vapor absorption property, water absorption property, and a water vapor
dissipation property.
[0006] It is one feature of the invention that the humidity control member has properties
which are highly absorbant of water as well as water vapor and that it also has a
water vapor dissipation property, and that this humidity control member is used in
lieu of Japanese paper which has a poor water absorption property and has substantially
no water vapor absorption property.
[0007] It is another feature of this invention that the humidity control member can be used
in a versatile fashion, i.e., it can be disposed on the bottom, the side walls or
the entire inner wall surfaces of a liquid container package.
Brief Description of Drawings
[0008]
Fig. 1 is a sectional view showing a relative humidity control member accommodated in a
liquid container package according to the invention;
Fig. 2 is a perspective view showing an example of use of the humidity control member;
Figs. 3 and 4 are perspective views, each showing a different example of use of the
humidity control member;
Fig. 5 is an exploded perspective view showing the liquid container package according
to the invention;
Fig. 6 is a perspective view showing the assembled form of the liquid container package
shown in Fig. 5; and
Fig. 7 is a perspective view showing a prior art liquid container package.
Best Mode for Carrying Out the Invention
[0009] The invention will now be described in conjunction with the preferred embodiments
thereof with reference to the drawings.
[0010] Fig. 1 is a sectional view showing a humidity control member accommodated as a liquid
or water absorber in a liquid container package according to the invention. Resinous
material 2 having a water vapor absorption property, a water absorption property,
and a water vapor dispersion perperty is provided in an embossed form between two
water- and water vapor-permeable sheets 3 (such as paper sheets). Resinous material
2 has a water absorption capacity of
10 to 1,000 cc, preferably 100 to 800 cc, more preferably 300 to
700 cc, per one gram. Such a water-absorptive resinous material as noted above is well-known;
for example, an acrylic acid resin mainly composed of potassium polyacrylate (marketed
under a trade name "Arasoap 800A" by
Arakawa Kagaku Kogyo Co., Ltd.).
[0011] This humidity control member has a mesh-like structure constituted by resinous material
2, water being trapped in the mesh structure. It can cope with a temperature rise
or like changes to maintain a saturation state inside the package by releasing water
vapor. When water vapor is increased beyond the saturation state, it positively absorbs
moisture. When such humidity control member is provided in the sealed liquid container
package, water generated due to various causes is absorbed and dispersed by the resin
particles, so that it is possible to maintain at all time the saturation state inside
the sealed liquid container package. In other words, it is possible to suppress dispersion
of water by evaporation from the liquid container such as a blood bag and also suppress
generation of water drops.
[0012] Now, an embodiment of the invention and a comparative example will be described with
reference to the drawings.
[0013] Fig. 1 shows a humidity control member for a package for blood bags (liquid containers)
according to the invention. Reference numeral 1 designates the humidity control member.
Humidity control member
1 consists of an embossing of a pair of slightly water- and water vapor permeable paper
sheets 3 with resinous material 2 being disposed between the paper sheets 3. Resinous
material 2 has a water vapor absorption property, a water absorption property, and
a water vapor dissipation property; for instance, it may be a highly water-absorptive
acrylic acid resin (in the form of particles mainly composed of potassium polyacrylate
[available under a trade name "Arasoap 800A" by Arakawa Kagaku Kogyo Co., Ltd.,] with
a water absorption capacity of 950 cc/g). Humidity control member 1 contains 20 g
of the highly water-absorptive resin per 1
m2
.
[0014] Fig. 2 shows how the humidity control member according to the invention is used in
an embossed form. As is shown, molding 4 of humidity control member 1, which has substantially
the same shape as package A, is prepared and disposed in package A. After humidity
control molding 4 has been set in package A, blood bags (not shown) are enclosed in
package A, which is then sealed with lap B.
[0015] The method of disposing the humidity control member in package A as shown in Fig.
2 is by no means limitated. For example, it is possible to use humidity control molding
member 5 as shown in Fig. 3, or disposed relative humidity control molding member
6 only on the bottom of package as shown in Fig. 4.
[0016] The shapes of humidity control molding members 4 to 6 obtained from humidity control
member 1 are by no means limitated, and member 1 may be processed to any shape and
size which conforms to package A.
[0017] Fig. 5 shows an example of packing blood bags (not shown) by using a package as shown
in Fig. 2. As shown, this package is formed by using two humidity control members
4 as shown in Fig. 2. More particularly, humidity control members
41 and 42 are set in respective packages A
1 and A
2. Then, after setting the blood bags in packages A
1 and A
2, packages A
l and A
2 are sealed with respective laps B
1 and B
2.Thereafter, packages A
l and A
2 with the blood bags sealed therein are overlaid, face-to-face, with laps B
1 and B
2 and then their edges are heat-sealed together, thus completing the package as shown
in Fig. 6.
[0018] Packages A
l and A
2 each have a volume of 65 mm by 105 mm by 180 mm. When each of packages A
1 and A
2 contains five sets of blood containers with 200-cc of collected blood (a total liquid
content of 140 cc), it suitably contains 0.05 to 5 g, preferably 0.1 to 2 g, of the
highly water-absorptive resin. If the resin is excessively contained therein, the
moisture in package A is excessively absorbed so that the blood bag content eventually
begins to lack water content. If the resin is insufficiently contained therein, on
the other hand, failure of the resin to sufficiently absorb the moisture is liable.
[0019] A temperature cycle test was conducted on a liquid container package consisting of
two packages A
l and A
2 with blood bags sealed therein and sealed together, face-to-face, with laps B
1 and B
2. The test was conducted by transferring the package, every 3 hours, between a temperature
controller at 60°C and a refrigerator at 6°C and repeating this cycle ten times, and
subsequently checking the extent of wetting to the surface of the blood bags. A like
temperature cycle test was conducted under the same conditions on a package (refer
to Fig. 7), which was formed in the same manner as the package shown in Fig. 6, except
that conventional Japanese paper (or Japanese art paper) was used in lieu of humidity
control member 4 according to the invention and was disposed under the bottom of the
individual blood containers.
[0020] With the package according to the invention, the surface of the blood bags on the
upper side of humidity control member 4 was proven to be only slightly wet, and the
blood bag surface on the lower side of humidity control member 4 was perfectly dry.
With the contrasting package formed by using Japanese paper, the blood bag surface
on the upper side of the Japanese paper was considerably wet, and the blood bag surface
on the lower side of the Japanese paper was proven to be extremely wet.
[0021] It was thus confirmed that the wetting of the blood bag surface can be extremely
remedied in cases where humidity control member 4 is used as compared to the case
where the Japanese paper was used.
[0022] As has been described in the foregoing, according to the invention, it is possible
to maintain the saturation state of humidity in a sealed package containing blood
bags or like liquid containers. It is thus possible to prevent water vapor from condensing
inside the package as well as to suppress the dispersion of water content from the
liquid container. Further, since the liquid container surface is not wet, a label
indicating the blood type or like data can be reliably applied to the liquid container
surface.
Industrial Applicability
[0023] As explained above, a liquid container package according to this invention is useful
for every kinds of sealed package which is required to keep the inside thereof free
from the generation of moisture condensation, and in particular for a package which
is adapted to keep a vapor permeable liquid container therein for a long period of
time.
1. A liquid container package comprising a liquid container having a wall permeable
to water vapor and containing a liquid, a package for hermetically wrapping one or
more of said liquid containers, and a humidity control member disposed between said
liquid container or containers and said package and comprising a water-and water vapor-permeable
sheet and resinous material enclosed by said water- and water vapor-permeable sheet
and having a water vapor absorption property, a water absorption property and a water
vapor dissipation property.
2. The liquid container package according to claim 1, wherein said resinous material is in the form of resin particles.
3. The liquid container package according to claim 2, wherein the water absorption
capacity of said resin particles is 10 to 1,000 cc/g.
4. The liquid container package according to claim 3, wherein the water absorption
capacity of said resin particles is 100 to 800 cc/g.
5. The liquid container package according to claim 4, wherein the water absorption capacity of said resin particles is 300 to 700 cc/g.
6. The liquid container package according to claim 1, wherein said liquid container
is a blood bag.
7. The liquid container package according to claim 1, wherein said resin particles
are contained in a quantity such that the liquid container surface is not substantially
wetted and that the water content is not excessively absorbed in the liquid container
content.
8. The liquid container package according to claim 1, wherein said humidity control
member is disposed on the bottom of said package.
9. The liquid container package according to claim 1, wherein said humidity control
member is disposed on the bottom and side walls of said package.
10. The liquid container package according to claim 1, wherein said humidity control
member is disposed on substantially the entire inner wall surfaces of said package.
11. The liquid container package according to claim 1, wherein said resin particles
are contained by 20 g per 1 mm2 of said humidity control member.
12. The liquid container package according to claim 1, wherein said resinous material consist of an acrylic acid resin mainly composed
of potassium polyacrylate.