Medical supplies abstract
A packaging material is formed by a substrate, and an inner sealing
layer comprising a polyolefin layer and an aqueous dispersion-type
polyester resin layer successively disposed on the substrate. The
aqueous dispersion-type amorphous polyester resin layer contains
an anionic surfactant or an amphoteric surfactant and is substantially
free from an organic solvent having a boiling point of at most 100.degree.
C. The thus-formed packaging material is excellent in aroma-retentivity,
aroma non-adsorptivity, particulate non-adhesion, low residual solvent
and sealability. The packaging material is also free from environmental
problem and is therefore suitable as a packaging material for particulate
medical supplies and health foodstuff.
Medical supplies claims
1. A packaging material, comprising a substrate, and an inner sealing
layer comprising a polyolefin layer and an aqueous dispersion-type
polyester resin layer successively disposed on the substrate, wherein
said aqueous dispersion-type amorphous polyester resin layer contains
an anionic surfactant or an amphoteric surfactant and is substantially
free from an organic solvent having a boiling point of at most 100.degree.
C.
2. A packaging material according to claim 1, wherein said substrate
includes at least an oxygen and/or moisture barrier layer, and a
base layer, below the polyolefin layer.
3. A packaging material according to claim 2, wherein the barrier
layer comprises at least one of aluminum foil, ethylene-vinyl alcohol
copolymer layer, vapor deposited film of inorganic material, and
polypropylene film.
4. A packaging material according to claim 2, wherein the base
layer comprises at least one of paper, cellophane, polyester, nylon
and polypropylene.
5. A packaging material according to claim 1, wherein said anionic
surfactant comprises an alkyl sulfate-type or a polyoxyethylene
alkyl ether acetate-type anionic surfactant.
6. A packaging material according to claim 1, wherein the amorphous
polyester resin layer is formed on the polyolefin layer via an anchor
coating layer.
7. A packaging product, comprising: a packaging material according
to claim 1, and a particulate medical supply or a health foodstuff
sealed up in the packaging material.
8. A packaging material according to claim 3, wherein the base
layer comprises at least one of paper, cellophane, polyester, nylon
and polypropylene.
9. A packaging material according to claim 2, wherein said anionic
surfactant comprises an alkyl sulfate-type or a polyoxyethylene
alkyl ether acetate-type anionic surfactant.
10. A packaging material according to claim 3, wherein said anionic
surfactant comprises an alkyl sulfate-type or a polyoxyethylene
alkyl ether acetate-type anionic surfactant.
11. A packaging material according to claim 4, wherein said anionic
surfactant comprises an alkyl sulfate-type or a polyoxyethylene
alkyl ether acetate-type anionic surfactant.
12. A packaging material according to claim 2, wherein the amorphous
polyester resin layer is formed on the polyolefin layer via an anchor
coating layer.
13. A packaging material according to claim 3, wherein the amorphous
polyester resin layer is formed on the polyolefin layer via an anchor
coating layer.
14. A packaging material according to claim 4, wherein the amorphous
polyester resin layer is formed on the polyolefin layer via an anchor
coating layer.
15. A packaging material according to claim 5, wherein the amorphous
polyester resin layer is formed on the polyolefin layer via an anchor
coating layer.
16. A packaging product, comprising: a packaging material according
to claim 2, and a particulate medical supply or a health foodstuff
sealed up in the packaging material.
17. A packaging product, comprising: a packaging material according
to claim 3, and a particulate medical supply or a health foodstuff
sealed up in the packaging material.
18. A packaging product, comprising: a packaging material according
to claim 4, and a particulate medical supply or a health foodstuff
sealed up in the packaging material.
19. A packaging product, comprising: a packaging material according
to claim 5, and a particulate medical supply or a health foodstuff
sealed up in the packaging material.
20. A packaging product, comprising: a packaging material according
to claim 6, and a particulate medical supply or a health foodstuff
sealed up in the packaging material.
Medical supplies description
FIELD OF THE INVENTION AND RELATED ART
[0001] The present invention relates to a packaging material in
the form of a bag suitable for packaging powdery, granular or particulate
medical supplies (inclusive of drugs, medicine, and cosmetics) and
health foodstuff, and also a packaged product of such medical supplies
and the like as content materials.
[0002] Packaging materials for powdery, granular or particulate
(hereinafter inclusively referred to as "particulate")
medical supplies and health foods require special properties and
care compared with packaging materials for other content materials,
such as sundries and general foods. The special properties and care
include no adverse effects against environments at the time of disposal
thereof in addition to packaging properties adapted to storage of
particulate content materials. This is because users of medical
supplies and health foods are generally also sensitive to such adverse
effects against environments at disposal of the packaging materials.
[0003] More specifically, a packaging material providing a packaging
bag for particulate medical supplies and health foods (hereinafter
represented by "medical supplies") generally has a laminate
structure including a substrate comprising a base layer comprising
paper, cellophane, polyester, nylon, polypropylene, etc., and a
layer of aluminum foil or gas barrier film disposed on the base
layer, and further a thermoplastic sealing resin layer formed on
the substrate. The packaging material is formed into a various form
of bag, which is filled with a content material and then again heat-sealed
at its inlet mouth to provide a bag-packaged product.
[0004] Such a packaging material for particulate medical supplies
is required to have various properties, inclusive of: freeness from
giving an odor to the enclosed content material, as a matter of
course; a property of not impairing aroma of the content material
where the content material has aroma by containing a volatile drug,
a flavor or a refrigerant (=aroma-retentivity); a property of not
reducing such aroma (=aroma non-adsorptivity); and a low residual
solvent, to the utmost degree. The packaging material is further
required to satisfy properties of not leaving the particulate content
material therein due to physical attachment of the particles to
the inner side thereof (=particulate non-adhesion); heat-sealability,
particularly a property of providing a good seal even in the presence
of some particulate content material at the place of seal (=foreign
matter sealability); etc. Polyolefins (inclusive of polyethylene,
polypropylene, ethylene-propylene copolymer and ethylene-vinyl acetate
copolymer) most frequently used as a heat sealing material for packaging
materials, generally leave a problem with respect to the aroma non-adsorptivity,
and also a problem with respect to the aroma-retentivity because
it contains an anti-blocking agent or a lubricant for the film formation
and also an antioxidant, etc., added thereto. Polyester resins are
known to be excellent in the aroma-retentivity and the aroma non-adsorptivity
(e.g., as disclosed in "Shokuhin Hozon Binran (Food Preservation
Handbook)", published from K.K. Creative Japan (Jun. 12, 1992)),
but an amorphous polyester resin of solvent type is problematic
because it leaves much residual solvent.
[0005] A packaging material having a laminate structure of a polyolefin
layer and a vinylidene chloride resin layer successively laminated
on the substrate has been successfully used as a packaging material
for particulate medical supplies because it is good in all of the
above-mentioned aroma-retentivity, aroma non-adsorptivity, low residual
solvent, particulate non-adhesion and heat-sealability. However,
as for the vinylidene chloride resin which is one of chlorine-containing
resins, there are increasing demands for replacement thereof.
SUMMARY OF THE INVENTION
[0006] Accordingly, a principal object of the present invention
is to provide a packaging material which is excellent in the above-mentioned
properties required of a packaging material for particulate medical
supplies, etc., such as aroma-retentivity, aroma non-adsorptivity,
particulate non-adhesion, low residual solvent and heat-sealability,
and is also free from environmental problems.
[0007] According to the present invention, there is provided a
packaging material, comprising: a substrate, and an inner sealing
layer comprising a polyolefin layer and an aqueous dispersion-type
polyester resin layer successively disposed on the substrate, wherein
said aqueous dispersion-type amorphous polyester resin layer contains
an anionic surfactant or an amphoteric surfactant and is substantially
free from an organic solvent having a boiling point of at most 100.degree.
C.
[0008] The packaging material of the present invention is most
characterized in that for the surface layer heat-sealant, the use
of a solvent-type amorphous polyester resin as a conventional heat-sealant
is obviated, but an aqueous dispersion-type amorphous polyester
resin is used by substantially removing a low-boiling organic solvent
having a boiling point of at most 100.degree. C. while using an
anionic surfactant or an amphoteric surfactant added thereto instead
of the organic solvent. The anionic or amphoteric surfactant has
not only an effect of suppressing the lowering in dispersibility
of the amorphous polyester resin in an aqueous dispersion liquid
due to the removal of a low-boiling organic solvent to retain the
coating applicability of the amorphous polyester resin aqueous dispersion
liquid but also a function of ensuring the particulate non-adhesion
property.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0009] (Substrate)
[0010] The substrate of the packaging material according to the
present invention may have a similar material structure as those
used in conventional packaging materials for medical supplies. More
specifically, the substrate may have a structure including an optionally
printed base layer of paper, cellophane or a film of plastic, such
as polyester, nylon or polypropylene, and an optional barrier layer
applied thereon of an aluminum foil or a barrier film, such as ethylene-vinyl
alcohol copolymer film, a vapor-deposited film of an inorganic material,
such as silica, alumina or aluminum, or a polypropylene film. The
barrier layer may preferably exhibit barrier characteristics, such
as an oxygen permeability of at most 50 ml/m.sup.2.day.MPa (according
to JIS K7126B) and/or a water vapor permeability of at most 5 g/m.sup.2.day
(according to JIS K7129B).
[0011] (Polyolefin Layer)
[0012] On the barrier layer of such a substrate as described above,
a polyolefin layer is laminated. Examples of the polyolefin may
include: polyethylene, polypropylene and ethylene-vinyl acetate
copolymers having a vinyl acetate content of at most 15 wt. %. Among
these, low-density polyethylene having a density of 0.915-0.925
g/cm.sup.3 is preferably used. The polyolefin layer may suitably
have a thickness of ca. 20-50 .mu.m. A thickness below 20 .mu.m
is liable to result in a lower sealing strength (as measured according
to a method described hereinafter). A thickness in excess of 50
.mu.m is not expected to provide a further increased sealing strength
and becomes economically disadvantageous. For the lamination coating
of the polyolefin layer on the substrate, it is also possible to
form an anchor coating layer of, e.g., polyurethane-based, polyethyleneimine-based
and polybutadiene-based adhesives.
[0013] (Aqueous Dispersion-Type Amorphous Polyester Resin Layer)
[0014] According to the present invention, the polyolefin layer
optionally coated with an anchor coating layer of, e.g., a polyurethane-based
adhesive, is coated with an aqueous dispersion-type amorphous polyester
resin layer by application of an aqueous dispersion liquid of amorphous
polyester resin.
[0015] An amorphous polyester resin is generally a copolyester
formed by copolymerization of a polybasic acid having at least two
carboxyl groups (or anhydride thereof) and a polyhydric alcohol
having at least two hydroxyl groups with the proviso that at least
one of the polybasic acid and/or the polyhydric alcohol is used
in two or more species. It is desirable to use an amorphous polyester
resin showing substantially no heat absorption peak attributable
to crystal melting point when subjected to heating at rate of 10.degree.
C./min. in a nitrogen atmosphere by using a differential scanning
calorimeter (DSC), but it is possible to use one showing a heat-absorption
peak enthalpy (crystal melting enthalpy .DELTA.Hc) of ca. 10 J/g
or below. Examples of the polybasic acid may include: aromatic dicarboxylic
acids, such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic
acid; aliphatic dicarboxylic acid, such as succinic acid and anhydride
thereof and adipic acid; and optionally added three or more-functional
polybasic acids, such as trimellitic acid, pyromellitic acids and
anhydrides of these. It is preferred that at least 70 mol % of the
polybasic acid comprises an aromatic dicarboxylic acid, including
at least 65 mol. % of terephthalic acid.
[0016] Examples of the polyhydric alcohol may include: aliphatic
glycols having 2-10 carbon atoms, such as ethylene glycol, 1,2-propylene
glycol, 1,3-propanediol, and neopentyl glycol; alicyclic glycols,
such as 1,4-cyclohexanebimethanol; and optionally three or more
functional polyhydric alcohols, such as glycerin, trimethylolpropane
and pentaerythritol. It is preferred that at least 65 mol % of the
polyhydric alcohol comprises ethylene glycol and/or neopentyl glycol.
[0017] At least one of the above-mentioned polybasic acid and/or
polyhydric alcohol is used in two or more species while controlling
their compositional ratios and degree of polycondensation, thereby
providing an amorphous polyester resin suitably used in the present
invention, which has a glass transition temperature (Tg) of -20.degree.
C. to 80.degree. C., a polystyrene-equivalent number-average molecular
weight (Mn) of 5000 to 25000 as measured by GPC (gel permeation
chromatography) and an acid value of 8 to 40 mgKOH/g. Generally,
a high molecular weight and a low Tg are preferred in order to provide
an increased heat-seal strength, whereas a low molecular weight
and a high Tg are preferred from the viewpoint of anti-blocking
of the heat-sealing layer. In order to harmonize the heat-seal strength
and the anti-blocking property, it is preferred to use a combination
of an amorphous polyester resin having a Tg of at least 40.degree.
C. and an amorphous polyester resin having a Tg below 40.degree.
C.
[0018] The above-mentioned amorphous polyester resin is used in
the form of an aqueous dispersion liquid thereof. For the purpose
of neutralizing the polyester resin to improve the water-dispersibility
thereof, it is preferred to add a basic compound, such as N,N-diethanolamine,
triethylamine or ammonia, and it is also possible to optionally
add a compound functioning as a protective colloid, such as polyvinyl
alcohol or carboxymethyl cellulose, and/or an organic solvent, selected
from lower alcohols functioning as a plasticizer for the polyester
resin, such as ethanol, isopropanol and butanol; ketones, such as
methyl ethyl ketone; esters, such as ethyl acetate; and ethylene
glycol monoalkyl ethers (so-called cellosolves). Particularly, an
organic solvent having a boiling point of 150.degree. C. or below
has a high ability of plasticizing the polyester resin and is preferred
for improving the water dispersibility of a high-Tg polyester resin
used for enhancing the anti-blocking property of the resultant heat-sealing
layer, whereas the remaining thereof as a residual solvent in the
heat-sealing layer is unsuitable for the packaging material for
medical supplies according to the present invention. Accordingly,
such an organic solvent having a boiling point of at most 150.degree.
C., especially at most 100.degree. C., even if used for improving
the water-dispersibility, should preferably be substantially removed
by, e.g., azeotropic distillation with water, prior to the use of
the aqueous dispersion liquid for preparation of the packaging material.
[0019] Accordingly, the condition that the aqueous dispersion-type
amorphous polyester resin layer is substantially free from the organic
solvent having a boiling point of at most 100.degree. C. in the
present invention, is preferably satisfied by a residual solvent
of below 8 mg/m.sup.2, more preferably below 5 mg/m.sup.2, when
a resultant packaging material including a heat-sealing layer is
subjected to a residual solvent measurement which is described hereinafter.
[0020] For the preparation of an aqueous dispersion liquid of the
amorphous polyester resin, it is important to comminute or finely
pulverize the amorphous polyester resin. The comminution may for
example be effected by jet pulverization treatment, wherein a fluid
or fluids including the above ingredients is/are caused to flow
or be jetted under a high pressure and high speed condition to comminute
the resin particles therein by collision of the fluid(s) to each
other or to an impinging plate means, etc.
[0021] For the preparation of an aqueous dispersion liquid of amorphous
polyester resin, there may be applied techniques disclosed in e.g.,
JP-A 9-296100, JP-A 11-61035, JP-A 2000-26709 and JP-A 2000-313793
including a summary thereof as described above.
[0022] The aqueous dispersion liquid of amorphous polyester resin
may suitably have a solid matter content on the order of 20 to 50
wt. %.
[0023] According to the present invention, the aqueous dispersion
liquid of amorphous polyester resin is caused to contain an anionic
surfactant or an amphoteric surfactant. The anionic surfactant or
amphoteric surfactant contributes to not only the improvement in
water dispersibility and coating applicability onto the polyolefin
layer of the amorphous polyester resin but also the formation of
a heat-sealing layer having a good particulate non-adhesion property
by functioning as a kind of antistatic agent. A cationic or a nonionic
surfactant has a poor miscibility with the aqueous dispersion liquid
of amorphous polyester resin, so that the resultant aqueous dispersion
liquid is liable to cause gelling or shows a poor coating applicability
onto the polyolefin layer, thus failing to form a smooth amorphous
polyester resin layer.
[0024] Also in view of the adaptability to medical supplies, alkyl
sulfate-type and polyoxyethylene alkyl ether acetate-type anionic
surfactants, and betain-type amphoteric surfactants, are preferred,
and among these, anionic surfactants giving a good particulate non-adhesion
property are further preferred.
[0025] The anionic surfactant or amphoteric surfactant may preferably
be used in a proportion of 0.2 to 10.0 wt. %, particularly 2.5 to
5.4 wt. % (based on its solid matter) with respect to the solid
matter content in the aqueous dispersion liquid of amorphous polyester
resin. Below 2 wt. %, the addition effect is scarce, and the use
in excess of 10 wt. % is liable to lower the resultant seal strength.
[0026] Other agents can be added to the aqueous dispersion liquid
of amorphous polyester resin in addition to the surfactant. Examples
of such other agents may include: anti-blocking agents, slip agents
(lubricants), etc.
[0027] The amorphous polyester resin layer may preferably be formed
on the polyolefin layer at a coating rate of 1 to 7 g/m.sup.2, particularly
3 to 4 g/m.sup.2 based on solid. Below 1 g/m.sup.2, the resultant
seal strength is liable to be unstable, and above 7 g/m.sup.2, the
resultant amorphous polyester resin layer is liable to have an increased
residual solvent content due to a lowering in drying efficiency.
The application of the aqueous dispersion liquid of amorphous polyester
resin may be performed by any arbitrary method as far as it allows
the control of a uniform coating amount.
[0028] The amorphous polyester resin layer after the application
as an aqueous dispersion liquid may be dried at a temperature of
ca. 80 to 130.degree. C. The drying at a temperature of 135.degree.
C. or above is liable to cause fusion-sticking of ears of the packaging
material, thus being unsuitable in some cases.
[0029] (Anchoring Treatment)
[0030] Prior to the coating with the aqueous dispersion liquid
of amorphous polyester resin, the polyolefin layer may preferably
be subjected to an anchoring treatment, such as a corona treatment
or the coating with an anchor coating agent such as two part-type
polyurethane, so as to improve the coatability with the aqueous
dispersion liquid. The anchor coating agent may suitably be applied
at ca. 0.2 to 0.7 g/m.sup.2 (as solid).
[0031] (Heat Sealing)
[0032] The packaging material prepared in the above-described manner
may be used for provision of bag-shaped products through sequential
steps of heat-sealing into various shapes of bags, filling with
a content material and further heat-sealing of the inlets of the
bags.
[0033] The heat sealing may generally be performed at a temperature
of 120 to 180.degree. C. under application of a pressure of ca.
0.1 to 0.3 MPa, so as to provide a seal strength of preferably at
least 5N/15 mm, more preferably 8N/15 mm or higher. The heat-sealing
layer based on the combination of the polyolefin layer and the amorphous
polyester resin layer is characterized in that the resultant seal
strength exhibits a smaller degree of lowering with time compared
with the conventional heat-sealing layer based on the combination
of a polyolefin layer and a vinylidene chloride resin layer.
[0034] Examples of the laminate layer structure of the packaging
material according to the present invention are shown below with
some component materials represented by their abbreviations (explained
after) but these are not exhaustive.
[0035] Ex.1) PET(12)/AC/PE(15)/AL(9)/AC/PE(40)/AC/A.PET(3)
[0036] Ex.2) glassine(30.5)/AC/PE(15)/AL(7)/AC/PE(40)/AC/A.PET(3)
[0037] Ex.3) plain cellophane(30)/AC/PE(15)/AL(9)/AC/PE(40)/AC/A.PET(3)
[0038] Ex.4) PET(12)/DL/EVOH(12)/AC/PE(40)/AC/A.PET(3)
[0039] Ex.5) PET(12)/DL/OPP(20)/AC/PE(40)/AC/A.PET(3)
[0040] Ex.6) NY(15)/AC/PE(15)/AL(9)/AC/PE(40)/AC/A.PET(3)
[0041] Ex.7) PET(12)/DL/silica-deposited PET(12)/AC/PE(40)/AC/A.PET(3)
[0042] (Abbreviations for the Layer Component Materials)
[0043] PET: polyester film,
[0044] AC: anchor coating,
[0045] AL: aluminum foil,
[0046] PE: polyethylene,
[0047] EVOH: ethylene-vinyl alcohol copolymer film,
[0048] DL: dry lamination adhesive,
[0049] OPP: biaxially stretched polypropylene film,
[0050] NY: biaxially stretched nylon film,
[0051] A.PET: amorphous polyester resin.
[0052] The numerals in parentheses following the component materials
represent a layer thickness (.mu.m) of the materials except that
the same represents a basis weight of g/m.sup.2 for glassine, A.PET
(amorphous polyester resin layer) and plain cellophane.
[0053] (Medical Supplies)
[0054] As described hereinbefore, the packaging material of the
present invention is particularly adapted to packaging of particulate
medical supplies (inclusive of drugs, medicine, and cosmetics) and
health foodstuff. The packaging material can be applicable to a
pellet-form product, etc., of ca. 5 mm or so in diameter (e.g.,
chlorella pellets) but is particularly suitable for packaging particulate
materials of at most 3 mm in diameter and is most suitable for packaging
of spherical adsorptive carbon particles of at most 0.5 mm in diameter,
which are liable to exhibit noticeable adhesion to the packaging
material.
PRODUCTION EXAMPLE
[0055] The production process of the packaging material according
to the present invention basically includes: a step of laminating
a polyolefin layer on a substrate, and a step of coating the polyolefin
layer with an aqueous dispersion-type amorphous polyester resin
layer. The aqueous dispersion-type amorphous polyester resin layer
contains an anionic surfactant or an amphoteric surfactant and is
substantially free from an organic solvent having a boiling point
of at most 100.degree. C.
[0056] Hereinbelow, an example process for producing a stick-form
packaging material for spherical adsorptive carbon as a representative
example of the packaging material, but this is of course not a limitative
example.
[0057] First, a corona-treated surface of a 12 .mu.m-thick base
polyester film is printed with information necessary for indicating
the product by a gravure rotary press. At this time, in addition
to an indication of the content material (product), an indication
of a cut line for indicating the part for opening of a stick-form
package is also printed.
[0058] Then, the thus-printed polyester film (12 .mu.m) is perforated
along the cut line for facilitating the opening of the stick-form
package.
[0059] The printed and perforated polyester film (12 .mu.m) and
a 9 .mu.m-thick aluminum foil as a barrier material are applied
to each other with a melted 15 .mu.m-thick polyethylene layer and
simultaneously the opposite face of the aluminum foil is coated
with a melted 40 .mu.m-thick polyethylene layer, by means of a tandem-type
extrusion laminator, to form a composite material (called hereinafter
a "stock sheet"). (In this instance, the printed polyester
film and the aluminum foil have been coated in advance with an anchor
coating agent for promoting the adhesion therebetween.) Then, the
polyethylene coating layer is subjected to a surface corona discharge
treatment to enhance the wettability.
[0060] The thus-prepared stock sheet is held for ca. 24 hours in
an environment of 35-40.degree. C. for aging to cure the anchor
coating agent.
[0061] Then, the polyethylene-coated (and corona discharge-treated)
face of the stock sheet is coated with an anchor coating layer and
then with an aqueous dispersion liquid of amorphous polyester resin
containing a surfactant and silica added thereto at a rate of ca.
3 g/m.sup.2, and dried.
[0062] The stock sheet is again kept for ca. 24 hours in an environment
of 35-40.degree. C. for aging to cure the anchor coating agent,
subjected to inspection and cutting, and wound up to obtain a roll
of packaging material.
EXAMPLES
[0063] Hereinbelow, the present invention will be described more
specifically based on Examples and Comparative Examples. The surface
seal layer-forming coating liquids and the resultant packaging materials
were evaluated with respect to the following items.
[0064] (1) Coating Applicability
[0065] The surface polyethylene layer of a stock sheet is coated
with a polyurethane-based anchor coating agent at a rate of ca.
0.5 g/m.sup.2 (as solid), and a prepared sample of amorphous polyester
resin aqueous dispersion liquid is uniformly applied thereon, to
evaluate the coating applicability of the sample dispersion liquid
by observation with eyes according to the following standard.
[0066] A: Provides a uniform coating.
[0067] B: Some coating irregularity is observed but a coating film
can be formed.
[0068] C: The coating liquid is repelled to fail in coating film
formation.
[0069] (2) Seal Strength
[0070] Heat sealing is performed by using a sample packaging material
under the conditions of: a sealing temperature of 150.degree. C.,
a pressure of 0.2 MPa and 1 second by using a sealing machine ("TP-701-B",
made by Tester Sangyo K.K.). The resultant seal is subjected to
T-shape peeling test at a peeling speed of 300 mm/min. to measure
a peeling strength as a seal strength, which is then evaluated according
to the following standard.
[0071] A: At least 8N/15 mm.
[0072] B: At least 5N/15 mm and below 8N/15 mm.
[0073] C: Below 5N/15 mm.
[0074] (3) Residual Solvent (Content)
[0075] An areal portion of 0.2 m.sup.2 is cut from a sample packaging
material and slit in a width of 5 mm. The slit sample is placed
in a 500 ml-Erlenmeyer flask, and the inner space thereof is replaced
by nitrogen gas blown thereinto. The Erlenmeyer flask is plugged
and warmed for 30 min. in a thermostatic chamber held at 80.degree.
C. Then, 1 ml of the gas inside the Erlenmeyer flask is sampled
and analyzed by gas chromatography to measure the amount of solvent
evaporated from the packaging material and calculate the amount
of solvent per unit area (mg/m.sup.2) as a residual solvent amount,
which is evaluated according to the following standard:
[0076] A: Below 5 mg/m.sup.2.
[0077] B: At least 5 mg/m.sup.2 and below 8 mg/m.sup.2.
[0078] C: At least 8 mg/m.sup.2.
[0079] (4) Smell (Sensory Test)
[0080] A sample packaging material is formed by sealing into a
tetrahedral empty bag and placed in a thermostatic chamber at 40.degree.
C. for ca. 1 day. Then, a corner of the tetrahedral bag is cut off,
and the substance emitted from inside the tetrahedral bag is smelled
and evaluated according to the following standard.
[0081] A: Almost no smell.
[0082] B: Slight smell is sensed, but not an unpleasant odor. Below
a tolerable limit.
[0083] C: Not an unpleasant smell, but lightly smells.
[0084] D: Unpleasant irritating odor, not tolerable.
[0085] Smell is caused by various factors, i.e., attributable to
the resin per se or the additive, processing conditions, and species
and amount of residual solvent, etc. As for the species of residual
solvent, toluene and methyl ethyl ketone, for example, emit irritating
smell which judged to be unpleasant odor, even if they remain in
a slight amount; and ethyl acetate and ethyl alcohol are judged
to be acceptable light smell, even if they remain in a small amount.
In the case of a substantial amount of residual solvent, even ethyl
acetate or ethyl alcohol is judged to be an irritating smell.
[0086] (5) Anti-Blocking Property
[0087] A sample packaging material obtained by application of an
aqueous dispersion liquid of amorphous polyester resin is cut into
5 to 10 sample sheets each measuring 100 mm.times.100 mm. The sample
sheets are stacked so that the faces and backs alternate each other,
and the stack is placed under a load of 10 kg and left standing
for 24 hours in an environment of 40.degree. C. Then, the stacked
sheets are peeled one by one to evaluate the anti-blocking property
according to the following standard.
[0088] A: The peeling can be performed with no resistance.
[0089] C: The peeling is accompanied with a resistance or cannot
be performed.
[0090] (6) Particulate Non-Adhesion Property (Residual Particle
Percentage)
[0091] Each packaging material formed into a tubular bag giving
a planar width of ca. 30 mm is formed by heat sealing, filled with
0.2 to 0.4 mm-dia. spherical adsorptive carbon particles ("KREMEZIN
particles", made by Kureha Chemical Industry Co., Ltd.) as
an example of substantially adherent medicine at an elevated temperature
of ca. 60.degree. C. and heat-sealed at ca. 90 mm intervals to form
rows of portion bag packages each having a planar shape of ca. 90
mm in length and ca. 30 mm in width and each containing ca. 2 g
of the carbon particles. (Further details of the above preparation
process are described in JP-A6-190021.) Then, each portion bag package
is opened at its one shorter-side end, and the content particles
are discharged through the opened end directed downwards. In this
state, a side face of the portion bag is filliped twice with a finger
for promoting the discharge of the content particles. Thereafter,
the weight of the particles remaining in the portion bag is measured
and divided by the original weight (=ca. 2 g) to calculate a residual
particle percentage, based on which the particulate non-adhesion
property is evaluated according to the following standard:
[0092] A: Below 1.0% (of residual particle percentage).
[0093] B: 1.0% to 2.0%.
[0094] C: Above 2.0%.
Example 1
[0095] Onto one surface of a 12 .mu.m-thick polyethylene terephthalate
film which had been printed on the other surface and perforated
in a line proximate to a place to be sealed, an anchor coating agent
was applied at a rate of ca. 0.5 g/m.sup.2, and polyethylene was
melt-applied in a thickness of 15 .mu.m, followed by application
thereto of a 9 .mu.m-thick aluminum foil. Further, a two part-type
polyurethane-based anchor coating agent was applied at ca. 0.5 g/m.sup.2,
and a 40 .mu.m-thick polyethylene layer was applied by melt-coating
thereon to form a foundation to be coated with a surface sealing
layer.
[0096] An aqueous dispersion liquid containing 30 wt. % (as solid)
of amorphous polyester resin of Tg=70.degree. C. and Mn=9000 and
substantially free from organic solvent having a boiling point of
at most 100.degree. C. ("ELITEL KZA-507 IS" made by Unitica
K.K.; obtained by substantially removing isopropanol (IPA) by azeotropic
distillation with water from "ELITEL KZA-5071" containing
18 wt. % of IPA) and an aqueous dispersion liquid ("ELITEL
KZM8701" made by Unitica K.K.) containing 30 wt. % (as solid)
of amorphous polyester resin of Tg=18.degree. C. and Mn=11000, were
blended at a weight ratio of 2:1, followed by addition thereto of
an anionic surfactant aqueous solution ("EMAL 2F", made
by Kao K.K.) containing 30 wt. % of solid matter including sodium
lauryl sulfate in an amount corresponding to 3 wt. % of the amorphous
polyester resin and 3 wt. % of silica fine powder as a lubricant,
to obtain an aqueous dispersion liquid of amorphous polyester resin.
[0097] The above-formed foundation surface on the substrate was
subjected to corona discharge treatment, then coated with a ca.
0.5 g/m.sup.2 of two part polyurethane-type anchor coating layer,
and further coated with the above-prepared aqueous dispersion liquid
of amorphous polyester resin, followed by drying at 120.degree.
C. for 12 sec., to obtain a packaging material according to the
present invention. In this instance, the aqueous dispersion liquid
of amorphous polyester resin exhibited a good coating applicability.
[0098] The above-prepared packaging material having an amorphous
polyester resin layer as the surface sealing layer exhibited a seal
strength of 15.4 N/15 mm, a residual solvent of 1.4 mg/m.sup.2,
no smell, a good anti-blocking property, and a good particulate
non-adhesion property as represented by a residual particle percentage
of 0.3%, thus exhibiting no problem at all with respect to any of
the evaluation items.
Comparative Example 1
[0099] A packaging material was prepared in the same manner as
in Example 1 except that the surface sealing layer was formed as
a 7 g/m.sup.2-coating layer of vinylidene chloride resin (PVDC)
("KREHALON LA-412", made by Kureha Chemical Industry Co.,
Ltd.)
[0100] The seal strengths of the packaging materials obtained by
the above Example 1 and Comparative Example 1 were measured with
time. The results are shown in Table 1 below.
1TABLE 1 Change with time of seal strength (N/15 mm) Example 1
Comparative Surface sealing Amorphous Example 1 layer polyester
resin PVDC Immediately after 15.4 N/15 mm 22 N/15 mm sealing After
1 day 14.3 N/15 mm 5 N/15 mm 3 days 12.9 N/15 mm 5 N/15 mm 7 days
11.3 N/15 mm 6 N/15 mm 1 month 11.2 N/15 mm -- N/15 mm
[0101] From the results shown in the above Table 1, it is understood
that the packaging material of the present invention having a surface
sealing layer of amorphous polyester resin (Example 1) was substantially
relieved from the lowering with time of seal strength caused by
progress of crystallization of vinylidene chloride resin as observed
in the packaging material of Comparative Example 1.
[0102] The results of evaluation of the packaging material of Example
1 with respect to the above-mentioned evaluation items are inclusively
shown in Table 2 appearing hereinafter together with those of packaging
materials obtained in the following Comparative Example, Reference
Example and Examples.
Comparative Example 2
[0103] A packaging material was prepared in a similar manner as
in Example 1 except for using an aqueous dispersion liquid of amorphous
polyester resin prepared in the same manner as in Example 1 except
for omitting the sodium lauryl sulfate. The aqueous dispersion liquid
exhibited poor coating applicability to fail in providing a polyester
coating layer, so that no evaluation of packaging material was possible.
Reference Example 1
[0104] A packaging material was prepared in a similar manner as
in Example 1 except for using an aqueous dispersion liquid of amorphous
polyester resin prepared in the same manner as in Example 1 except
for reducing the amount of sodium lauryl sulfate to 1 wt. % of the
amorphous polyester resin (solid). The aqueous dispersion liquid
exhibited poor coating applicability to fail in providing a polyester
coating layer, so that no evaluation of packaging material was possible.
Example 2
[0105] A packaging material was prepared in the same manner as
in Example 1 except for using an aqueous dispersion liquid obtained
by changing the amount of sodium lauryl sulfate to 2 wt. % of the
amorphous polyester resin (solid). The aqueous dispersion liquid
provided a polyester layer though it was accompanied with some coating
irregularity. The packaging material exhibited a seal strength of
21 N/15 mm, a residual solvent of 1.2 mg/m.sup.2, no smell, a good
anti-blocking property, and a residual particle percentage of 1.5%.
The coating applicability of the aqueous dispersion liquid and the
particulate non-adhesion property of the packaging material were
within a tolerable limit, and no problem was observed with respect
to the other evaluation items, so that the overall evaluation was
"good" as shown in Table 2.
Example 3
[0106] A packaging material was prepared in the same manner as
in Example 1 except for using an aqueous dispersion liquid obtained
by changing the amount of sodium lauryl sulfate to 4 wt. % of the
amorphous polyester resin (solid). The aqueous dispersion liquid
exhibited a good coating applicability. The packaging material exhibited
a seal strength of 15N/15 mm, a residual solvent of 0.9 mg/m.sup.2,
no smell, a good anti-blocking property, and a good particulate
non-adhesion property as represented by a residual particle percentage
of 0.2%, thus exhibiting no problem at all with respect to any of
the evaluation items.
Example 4
[0107] A packaging material was prepared in the same manner as
in Example 1 except for using an aqueous dispersion liquid obtained
by changing the amount of sodium lauryl sulfate to 5 wt. % of the
amorphous polyester resin (solid). The aqueous dispersion liquid
exhibited a good coating applicability. The packaging material exhibited
a seal strength of 15N/15 mm, a residual solvent of 1.5 mg/m.sup.2,
no smell, a good anti-blocking property, and a residual particle
percentage of 0.1%, thus exhibiting no problem at all with respect
to any of the evaluation items.
Example 5
[0108] A packaging material was prepared in the same manner as
in Example 1 except for using an aqueous dispersion liquid obtained
by changing the amount of sodium lauryl sulfate to 6 wt. % of the
amorphous polyester resin (solid). The aqueous dispersion liquid
exhibited a good coating applicability. The packaging material exhibited
a seal strength of 7N/15 mm, a residual solvent of 3.0 mg/m.sup.2,
no smell, a good anti-blocking property, and a residual particle
percentage of 0.1%. The seal strength was somewhat lowered but within
a tolerable limit, and no problem was observed with respect the
other evaluation items.
Example 6
[0109] A packaging material was prepared in the same manner as
in Example 1 except for using an aqueous dispersion liquid obtained
by changing the amount of sodium lauryl sulfate to 10 wt. % of the
amorphous polyester resin (solid). The aqueous dispersion liquid
exhibited a good coating applicability. The packaging material exhibited
a seal strength of 6N/15 mm, a residual solvent of 4.0 mg/m.sup.2,
no smell, a good anti-blocking property, and a residual particle
percentage of 0.1%. The seal strength was somewhat lowered but within
a tolerable limit, and no problems was observed with respect to
the other evaluation items.
2TABLE 2 The coating applicability of aqueous dispersion liquid
and results of evaluation of packaging materials with varying addition
amounts of sodium lauryl sulfate (SLS) Packaging material SLS Powder
amount Coating Seal Residual Anti- non- Overall Example (wt. %)
applicability strength solvent Smell blocking adhesion evaluation
Comp. 2 0 C -- -- -- -- -- Not good Ref. 1 1 C -- -- -- -- -- Not
good 1 3 A A A A A A Good 2 2 B A A A A B Good 3 4 A A A A A A Good
4 5 A A A A A A Good 5 6 A B A A A A Good 6 10 A B A A A A Good
Comparative Example 3
[0110] A packaging material was prepared in the same manner as
in Example 1 except for using a solution in ethyl acetate containing
30 wt. % of amorphous polyester resin of Tg=65.degree. C. and Mn=18000
instead of the aqueous dispersion liquid of amorphous polyester
resin used in Example 1.
[0111] The solution exhibited good coating applicability during
the preparation of the packaging material. The thus-prepared packaging
material exhibited a seal strength of 30N/15 mm, a residual solvent
of 230 mg/m.sup.2, an unpleasant, irritating and intolerable odor,
a good anti-blocking property and a residual particle percentage
of 0.9%. Thus, the residual solvent and smell were judge to be at
intolerable levels.
[0112] The evaluation results are inclusively shown in Table 3
described later together with those of the following Comparative
Examples and Examples.
Comparative Example 4
[0113] A packaging material was prepared in the same manner as
in Example 1 except for using a coating aqueous dispersion liquid
obtained in the same manner as in Example 1 except for replacing
the high-Tg amorphous polyester resin aqueous dispersion liquid
("ELITEL KZA-5071 S") used in Example 1 with an IPA-water
dispersion liquid of the same amorphous polyester resin containing
18 wt. % of IPA ("ELITEL KZA-5071") and also by omitting
the anionic surfactant aqueous solution.
[0114] The coating liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 18N/15 mm, a residual solvent
of 11.4 mg/m.sup.2, a slight smell, a good anti-blocking property,
and a residual particle percentage of 3.0%. The residual solvent
and the particle non-adhesion property were at intolerable levels,
so that the overall evaluation was "not good" as shown
in Table 3.
Comparative Example 5
[0115] A packaging material was prepared in the same manner as
in Example 1 except for using a coating aqueous dispersion liquid
obtained in the same manner as in Example 1 except for replacing
the high-Tg amorphous polyester resin aqueous dispersion liquid
("ELITEL KZA-5071 S") used in Example 1 with an IPA-water
dispersion liquid of the same amorphous polyester resin containing
18 wt. % of IPA ("ELITEL KZA-5071") and adding the anionic
surfactant aqueous solution containing the sodium lauryl sulfate
at 1 wt. % with respect to the amorphous polyester resin (as solid).
[0116] The coating liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 25N/15 mm, a residual solvent
of 10.1 mg/m.sup.2, a light smell though not unpleasant, a good
anti-blocking property, and a residual particle percentage of 1.5%.
The residual solvent was at an intolerable level.
Example 7
[0117] A packaging material was prepared in the same manner as
in Example 1 except for using a coating aqueous dispersion liquid
obtained in the same manner as in Example 1 except for changing
the ratio of the high-Tg amorphous polyester resin aqueous dispersion
liquid ("ELITEL KZA-5071 S") and the low-Tg amorphous
polyester resin aqueous dispersion liquid ("ELITEL KZM-8701")
from 2:1 to 3:1.
[0118] The coating liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 12N/15 mm, a residual solvent
of 0.9 mg/m.sup.2, no smell, a good anti-blocking property, and
a residual particle percentage of 0.4%, thus exhibiting no problem
at all with respect to any of the evaluation items.
Example 8
[0119] A packaging material was prepared in the same manner as
in Example 1 except for using a coating aqueous dispersion liquid
obtained in the same manner as in Example 1 except for changing
the ratio of the high-Tg amorphous polyester resin aqueous dispersion
liquid ("ELITEL KZA-5071 S") and the low-Tg amorphous
polyester resin aqueous dispersion liquid ("ELITEL KZM-8701")
from 2:1 to 4:1.
[0120] The coating liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 5N/15 mm, a residual solvent
of 1.2 mg/m.sup.2, no smell, a good anti-blocking property, and
a residual particle percentage of 0.5%. The seal strength was lowered
but within a tolerable range, and no problem was observed with respect
to the other evaluation items.
Example 9
[0121] A packaging material was prepared in the same manner as
in Example 1 except for using glassine (paper) having a basis weight
of 30.5 g/m.sup.2 as the base layer instead of the 12 .mu.m-thick
polyethylene terephthalate film and reducing the thickness of the
lower polyethylene layer from 40 .mu.m to 20 .mu.m.
[0122] The coating liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 9.4N/15 mm, a residual solvent
of 0.6 mg/m.sup.2, no smell, a good anti-blocking property, and
a residual particle percentage of 0.2%, thus exhibiting no problem
at all with respect to any of the evaluation items.
Example 10
[0123] A packaging material was prepared in the same manner as
in Example 1 except for using a 15 .mu.m-thick nylon film as the
base layer instead of the 12 .mu.m-thick polyethylene terephthalate
film.
[0124] The coating liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 18N/15 mm, a residual solvent
of 2.3 mg/m.sup.2, no smell, a good anti-blocking property, and
a residual particle percentage of 0.5%, thus exhibiting no problem
at all with respect to any of the evaluation items.
3TABLE 3 Effects of solvent, anionic surfactant and substrate.
Packaging material Powder Coating Seal Residual Anti- non- Overall
Example applicability strength solvent Smell blocking adhesion evaluation
Comp. 3 A A C D A A Not good Comp. 4 A A C B A C Not good Comp.
5 A A C C A B Not-good 7 A A A A A A Good 8 A B A A A A Good 9 A
A A A A A Good 10 A A A A A A Good
[0125] In the following Examples, the coating amount of the amorphous
polyester resin layer as the surface sealing layer was varied and
the influence thereof was evaluated. The results are inclusively
shown in Table 4 appearing later.
Comparative Example 6
[0126] A laminate structure before the provision of the surface
amorphous polyester resin layer and having the lower polyethylene
layer as the surface sealing layer was evaluated as a packaging
material.
[0127] The packaging material exhibited a seal strength of 20N/15
mm, a residual solvent of 0.5 mg/m.sup.2, a smell of polyethylene,
a good anti-blocking property, and a residual particle percentage
of 4.5%.
Example 11
[0128] A packaging material was prepared in the same manner as
in Example 1 except for changing the coating amount of the amorphous
polyester resin aqueous dispersion liquid prepared in Example 1
from 3 g/m.sup.2 to 1 g/m.sup.2.
[0129] The aqueous dispersion liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 8-20N/15 mm, a residual solvent
of 1.1 mg/m.sup.2, no smell, a good anti-blocking property, and
residual particle percentage of 2.0%. The seal strength was fluctuated
and the residual particle percentage was increased, whereas these
were both within tolerable ranges. No problem was observed with
respect to the other items.
Example 12
[0130] A packaging material was prepared in the same manner as
in Example 1 except for changing the coating amount of the amorphous
polyester resin aqueous dispersion liquid prepared in Example 1
from 3 g/m.sup.2 to 2 g/m.sup.2.
[0131] The aqueous dispersion liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 10-25N/15 mm, a residual solvent
of 1.1 mg/m.sup.2, no smell, a good anti-blocking property, and
residual particle percentage of 1.5%. The seal strength was fluctuated
and the residual particle percentage was increased, whereas these
were both within tolerable ranges. No problem was observed with
respect to the other items.
Example 13
[0132] A packaging material was prepared in the same manner as
in Example 1 except for changing the coating amount of the amorphous
polyester resin aqueous dispersion liquid prepared in Example 1
from 3 g/m.sup.2 to 4 g/m.sup.2.
[0133] The aqueous dispersion liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 18N/15 mm, a residual solvent
of 1.5 mg/m.sup.2, no smell, a good anti-blocking property, and
residual particle percentage of 0.3%, thus exhibiting no problem
at all with respect to any of the evaluation items.
Example 14
[0134] A packaging material was prepared in the same manner as
in Example 1 except for changing the coating amount of the amorphous
polyester resin aqueous dispersion liquid prepared in Example 1
from 3 g/m.sup.2 to 5 g/m.sup.2.
[0135] The aqueous dispersion liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 8N/15 mm, a residual solvent
of 2.3 mg/m.sup.2, no smell, a good anti-blocking property, and
residual particle percentage of 0.3%, thus exhibiting no problem
at all with respect to any of the evaluation items.
Example 15
[0136] A packaging material was prepared in the same manner as
in Example 1 except for changing the coating amount of the amorphous
polyester resin aqueous dispersion liquid prepared in Example 1
from 3 g/m.sup.2 to 6 g/m.sup.2.
[0137] The aqueous dispersion liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 7N/15 mm, a residual solvent
of 2.8 mg/m.sup.2, no smell, a good anti-blocking property, and
residual particle percentage of 0.4%. The seal strength was somewhat
lowered but was within a tolerable range, and no problem was observed
with respect to the other evaluation items.
Example 16
[0138] A packaging material was prepared in the same manner as
in Example 1 except for changing the coating amount of the amorphous
polyester resin aqueous dispersion liquid prepared in Example 1
from 3 g/m.sup.2 to 7 g/m.sup.2.
[0139] The aqueous dispersion liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 5N/15 mm, a residual solvent
of 5.5 mg/m.sup.2, no smell, a good anti-blocking property, and
residual particle percentage of 0.5%. The seal strength was lowered
and the residual solvent was increased, whereas these were within
tolerable ranges, and no problem was observed with respect to the
other evaluation items.
Reference Example 2
[0140] A packaging material was prepared in the same manner as
in Example 1 except for changing the coating amount of the amorphous
polyester resin aqueous dispersion liquid prepared in Example 1
from 3 g/m.sup.2 to 8 g/m.sup.2.
[0141] The aqueous dispersion liquid exhibited good coating applicability
during the packaging material preparation. The resultant packaging
material exhibited a seal strength of 3N/15 mm, a residual solvent
of 8.5 mg/m.sup.2, no smell, a good anti-blocking property, and
residual particle percentage of 0.5%. The seal strength and the
residual solvent exceeded the tolerable limits.
4TABLE 4 Effects of coating amounts (as solid) of the amorphous
polyester resin aqueous dispersion liquid. Packaging material Coating
Powder amount Coating Seal Residual Anti- non- Overall Example (g/m2)
applicability strength solvent Smell blocking adhesion evaluation
Comp. 6 0 -- A A C A C Not good 11 1 A A A A A B Good 12 2 A A A
A A B Good 1 3 A A A A A A Good 13 4 A A A A A A Good 14 5 A A A
A A A Good 15 6 A B A A A A Good 16 7 A B B A A A Good Ref. 2 8
A C C A A A Not good
[0142] (Evaluation of Surfactants)
[0143] Various aqueous liquids were prepared by adding aqueous
solutions of various surfactants in amounts of 3-5 wt. % (as solid)
of amorphous polyester resin to the same amorphous polyester resin
aqueous dispersion liquid as used in Example 1 but before the addition
of the anionic surfactant aqueous solution. The aqueous dispersion
liquids were respectively applied by hand coating (i.e., without
using a coating machine as in the preceding Examples) onto the same
laminate structure as in Example 1 having the surfacemost polyethylene
layer and before the coating with the amorphous polyester resin
layer, and dried in an oven, to prepare various packaging materials.
[0144] The coating applicability of the aqueous dispersion liquids
and the performances of the resultant packaging materials were evaluated
in the same manner as in the preceding Examples. The results are
inclusively shown in Table 5 below.
5TABLE 5 Effects of various surfactants Particle non- Surfactant
Addition Seal adhesion Trade name amount*1 Coating strength*3 (Residual
Type (Makers*2) Main Component (wt. %) Miscibility applicability
Smell (N/15 mm) particle) Anionic EMAL 2F sodium lauryl sulfate
3 A A A A A (Kao K. K.) (20) (0.3%) RLM-45NV polyoxyethylane alkyl
3 A A A A A (Kao K. K.) ether acetate (21) (0.3%) cationic JULIMER
quaternary ammonium salt on-coat -- A D B C SAT-5W [.alpha.-ethyl(trimethylammonium)]
soap-like (13) (7.7%) alkaloyl ester 5 B A C A C (gelled) light
(19) (6.8%) JULIMER quaternary ammonium on-coat -- A C B C SP-50TF
aliphatic type light (10) (6.5%) JULIMER do. on-coat -- A C C C
SPO-600 light (2, 4) (2.1%) JULIMER do. on-coat -- C Not evaluated
because of poor FC-80 (repelled) coating applicability COATAMINE
alkoxypropyltrimethyl-ammonium 3 C Not evaluated because of poor
miscibility E-80K chloride gelled (Kao K. K.) ADEKA COL CC-36 polyether
cation 3 A C Not evaluated because of poor (Asahi Denka K. K.) 5
A C coating applicability (repelled) non-ionic LEODOL sorbitan aliphatic
ester on-coat -- C Not evaluated because of poor SP-L10 (repelled)
coating applicability (Kao K. K.) LP-20R sorbitan aliphatic ester
on-coat -- A C A C (Nippon Yushi K. K.) light (19) (7.4%) EMANONE
polyoxyethyleneglycol monooleate 3 A C Not evaluated because of
poor 411O 5 A C coating applicability (Kao K. K.) (repelled) EMANONE
polyoxyethylene-hardene- d 3 A C Not evaluated because of poor CH25
castor oil 5 A C coating applicability (Kao K. K.) (repelled) mpohoteric
ANHITOL alkylcarboxymethyl 3 A A A A B 20YB hydroxyethylimidazolium
betaine (18) (1.3%) (Kao K. K.) **Notes to this table appear in
the next page. Notes to Table 5 in the preceding page. *1"On-coat"
in the column of "Addition amount" represents a coating
state where an amorphous polyester resin aqueous dispersion liquid
not containing the surfactant was first applied, and after drying,
a dilute solution in water or alcohol of the surfactant is applied
thereover in a thin film. *2"JULIMER" represents a product
from Nippon Jun'yaku K. K. *3Incidentally, somewhat higher levels
of seal strengths are recorded in Table 5 than in the preceding
Examples under the same heat-sealing conditions of 150.degree. C.,
0.2 MPa and 1.0 sec. This is primarily because the packaging materials
in these Examples were dried from two faces owing to the oven drying
whereas the packaging materials in the preceding Examples were dried
from one-side surfaces.
[0145] As described above, the present invention provides a packaging
material which is excellent in aroma-retentivity, aroma non-adsorptivity,
particulate non-adhesion, low residual solvent and sealability,
by coating a substrate successively with a polyolefin layer and
an aqueous dispersion liquid-type amorphous polyester resin layer
to which an anionic surfactant or an amphoteric surfactant has been
added. The packaging material is also free from environmental problem
and is therefore suitable as packaging materials for particulate
medical supplies and health foodstuff. |