JP2001181410A - Polypropylene-based resin sheet for ptp packaging - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polypropylene-based resin sheet for PTP packaging, not causing a trouble by a pitch lag in processing by a PTP packaging machine. SOLUTION: This polypropylene-based resin sheet for PTP packaging is characterized in that the propylene-based resin sheet comprises a propylene-based resin and has 0 to 4×10-4 (/ deg.C) shrinkage factor in a temperature fall process of thermomechanical analysis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polypropylene resin sheet for PTP (press through pack) packaging.

[0002]

2. Description of the Related Art PTP packaging is widely used, for example, in the field of pharmaceutical packaging for packaging solid preparations such as tablets and capsules. In the conventional PTP packaging, a sheet mainly made of a hard vinyl chloride resin is used as a bottom material from the viewpoint of transparency, moldability, stiffness, cost, and the like, and the bottom material has a solid content (for example, a pharmaceutical product). (A tablet or a capsule) is formed, a solid content is filled therein, and then sealed with a lid made of aluminum foil. Pharmaceutical tablets and capsules may deteriorate or deform due to moisture absorption. Conventionally, secondary packaging such as pillow packaging using a composite film containing an aluminum foil layer, or rigid vinyl chloride resin sheet However, these techniques have a problem in terms of cost, although a sheet obtained by laminating polyvinylidene chloride resin having excellent moisture resistance by coating or the like is used as a bottom material. In recent years, there has been a growing tendency to avoid vinyl chloride resin due to the problem of disposal.
Under such circumstances, a sheet made of a polypropylene-based resin has been evaluated for its excellent moisture-proof property, low cost, ease of disposal, etc., and instead of a conventionally used vinyl chloride resin sheet, a sheet for PTP packaging. Has come to be used as. PTP packaging is performed continuously using a dedicated packaging machine. Specifically, the raw resin sheet is fed out, heated to a predetermined temperature, sandwiched between a male mold and a female mold, and a pocket for accommodating the contents is formed using compressed air. The tablets and capsules are put into the container, an aluminum foil is attached so as to seal the tablets and capsules, and finally cut into an appropriate size. However, a PTP packaging sheet made of a polypropylene resin has a pitch between formed pockets (interval in the sheet flow direction).
Became shorter with time, and as a result, trouble occurred during processing.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a PT
An object of the present invention is to provide a polypropylene-based resin sheet for PTP packaging that does not cause trouble due to pitch shift in processing by a P packaging machine.

[0004]

The present inventors have SUMMARY OF THE INVENTION As a result of extensive studies to solve the above problems, using a polypropylene resin, thermomechanical analysis sheet shrinkage of 0 to 4 × 10 in the cooling process of the ^- It has been found that the above problem can be solved by setting the temperature to ⁴ (/ ° C.), and the present invention has been completed. That is, the present invention comprises a polypropylene resin and has a shrinkage rate of 0 to 4 × 10 ⁻⁴ (/
C.) is provided.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The polypropylene resin sheet for PTP packaging of the present invention comprises a polypropylene resin,
The shrinkage rate during the cooling process of thermomechanical analysis is 0-4 × 10 ^-4
(/ ° C.). The thermomechanical analysis (hereinafter referred to as TMA) in the present invention refers to a thermomechanical analyzer manufactured by Seiko Denshi Kogyo Co., Ltd .: TMA100 or an apparatus having the same function as the thermomechanical analyzer installed in an environment where the ambient temperature is adjusted to 23 ° C. Perform using In this apparatus, a 4 mm-wide sheet sample was sandwiched between upper and lower chucks in a heating furnace capable of adjusting the temperature, the distance between the upper and lower chucks was set to be 4 mm, and a weight of 1 g was hung on the lower chuck. In this state, the ambient temperature around the sheet specimen is changed, and the displacement of the lower chuck accompanying the temperature change is continuously recorded. The upper chuck is fixed.

[0006] A specific method of implementing TMA in the present invention is as follows. First, the sheet specimen is placed in a heating furnace, and the temperature in the heating furnace is increased from 23 ° C. to a predetermined temperature Tf ° C. at a rate of 5 ° C./min. When the ambient temperature reaches Tf, the heating is stopped, and the heating furnace covering the sheet sample is removed. Thereafter, the sheet sample is allowed to cool until the temperature sensor installed in the vicinity of the sheet sample indicates 23 ° C. During this series of operations, the displacement of the lower chuck is recorded. Assuming that the distance between the chucks before the test is L, the distance between the chucks at the temperature Tf is La, and the distance between the chucks at the time when the sheet sample is cooled until the temperature sensor indicates 23 ° C. is Lb, the TMA temperature decreasing process by the following equation. Is calculated. S (/ ° C.) = [(Lb−L) / La] / (Tf−23) The above temperature Tf is obtained by molding a sheet under the conditions described below.
This is a temperature corresponding to a molding temperature at which a pocket having a desired shape can be formed. In the case of a sheet made of a polypropylene resin, the temperature is usually in the range of 120 to 170 ° C.

The polypropylene sheet for PTP packaging of the present invention has a shrinkage ratio S of 0 to 4 × 10 ⁻⁴ (/ ° C.), preferably 0 to 3 × 10 ⁻⁴ (/ ° C.), and more preferably. Is 0 to 2 × 10 ⁻⁴ (/ ° C.). Shrinkage S value is 4
If it exceeds × 10 ⁻⁴ (/ ° C.), a significant pitch shift occurs in the packaging machine, which is not preferable, and the value of S is 0 (/ ° C.).
Is also not preferable because a significant pitch shift occurs.

The polypropylene resin used as the material of the polypropylene sheet for PTP packaging of the present invention means a propylene homopolymer and a copolymer containing 50% by weight or more of a repeating unit derived from propylene.
As the monomer components other than propylene constituting the copolymer, ethylene and α-olefins having 4 to 10 carbon atoms (for example, butene-1, 4-methylpentene-1, hexene-1, octene-1, And conjugated dienes (eg, butadiene and isoprene). The polypropylene-based resin is not particularly limited as long as it satisfies the above conditions, but from the viewpoint of suppressing the value of shrinkage S, a propylene homopolymer is preferable.

The sheet of the present invention is preferably made of a resin composition comprising the polypropylene resin and a filler. Fillers applicable to the present invention include inorganic fillers and organic fillers, and preferred inorganic fillers include calcium carbonate, magnesium carbonate, carbonates such as barium carbonate, barium sulfate, magnesium sulfate, Oxidation of sulfates such as calcium sulfate, phosphates such as magnesium phosphate and calcium phosphate, hydroxides such as magnesium hydroxide and aluminum hydroxide, alumina, silica, magnesium oxide calcium oxide, zinc oxide and titanium oxide Materials, aluminum powder, zeolite, kaolin, shirasu, clay, diatomaceous earth, talc, carbon black, clay and the like. Also, as a preferred organic filler,
Examples include cellulose-based powders such as pulp powder, synthetic resins such as nylon, polycarbonate, polymethyl methacrylate, and polystyrene, activated carbon, chitosan powder, chitin powder, and starch. From the viewpoint of preventing pitch shift, inorganic fillers are preferable, and among them, those having a needle-like shape are preferable. A preferred inorganic filler having a needle-like shape is magnesium sulfate whisker.
The content of the filler in the resin composition is preferably from 5 to 100 parts by weight, particularly preferably from 10 to 50 parts by weight, based on 100 parts by weight of the polypropylene resin.

The polypropylene-based sheet for PTP packaging of the present invention has a repeating unit content of butene-1 of 10 to 3%.
It may contain 0% by weight of a propylene / butene-1 random copolymer. A sheet containing such a propylene / butene-1 random copolymer exhibits excellent moldability in forming pockets.

The resin composition comprising the polypropylene-based resin and the filler constituting the polypropylene-based resin sheet of the present invention contains ethylene homopolymer, butene, pentene, hexene, and the like as long as the effects of the present invention are not significantly impaired. Α-olefin homopolymers such as heptene, ethylene and α
-Copolymers with olefins (butene, pentene, hexene, heptene, etc.), polymers of cyclic olefins, ethylene / methyl methacrylate copolymers, ethylene / vinyl acetate copolymers, ethylene / acrylic acid copolymers, ethylene Copolymer of ethylene / vinyl acetate / methyl methacrylate copolymer or other carboxylic acid having an ethylenically unsaturated bond or a derivative thereof with ethylene, polyvinyl alcohol, polyvinyl acetate, polycarbonate, polyester, polyamide, polystyrene, polymethacrylic acid Resins such as methyl, petroleum resin, thermoplastic elastomer, rubber, hydrogenated rubber and the like can be contained.

Particularly, when the resin composition comprising the polypropylene resin and the filler further contains a petroleum resin, the polypropylene resin sheet of the present invention can have excellent water vapor barrier properties. The petroleum resin includes a synthetic resin-based petroleum resin and a natural product-based petroleum resin, and a synthetic resin-based petroleum resin is preferable. For synthetic resin petroleum resins,
There are aliphatic hydrocarbon resins, aromatic hydrocarbon resins, alicyclic saturated hydrocarbon resins, and copolymers, but from the viewpoint of odor and transparency, among others, alicyclic saturated hydrocarbon resin petroleum Resins are preferred. In the present invention, when the resin composition contains a petroleum resin, the content is usually 1 to 10% by weight. If the addition amount is less than 1% by weight, a sufficient effect of improving the water vapor barrier property is difficult to be exhibited, and if it exceeds 10% by weight, the concentration of the low molecular weight component increases, which is not preferred.

Further, the resin composition may contain an antioxidant, an ultraviolet absorber, a light stabilizer, a lubricant, an antiblocking agent, an antistatic agent, a surfactant, a dye, a pigment as long as the effects of the present invention are not impaired. , A refractory agent, a plasticizer, a crystal nucleating agent and the like.

The resin composition suitable for the polypropylene resin sheet for PTP packaging of the present invention is a Banbury mixer,
Batch kneaders such as kneaders and rolls, single screw extruders,
It can be produced by an ordinary method using a continuous kneader such as a twin-screw extruder or a calender roll. The polypropylene resin sheet for PTP packaging of the present invention is, for example, T
It can be manufactured by a known method such as a die casting method and a calendar method. Further, the sheet produced by these methods may be further subjected to treatments such as stretching, rolling, heat treatment (annealing) and the like to obtain the sheet of the present invention.
The thickness of the sheet of the present invention is usually in the range of 0.16 to 0.6 mm, and preferably 0.25 to 0.35 mm. Even when performing processing such as stretching or rolling, the thickness after the processing is preferably within the above range.

[0015]

The polypropylene-based resin sheet for PTP packaging of the present invention is unlikely to cause shrinkage of the sheet during processing by the PTP packaging machine, and therefore does not cause trouble due to pitch shift.

[0016]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. [Measurement Method] (1) Shrinkage Rate of TMA in Temperature Decreasing Process The shrinkage ratio of the sheet in the cooling process of TMA was measured using a TMA measuring device (TMA100) manufactured by Seiko Instruments Inc. The measuring device installed in the room where the ambient temperature was adjusted to 23 ° C. was set in the tensile mode, a 4 mm wide sheet sample was sandwiched between upper and lower chucks so that the distance between the chucks was 4 mm, and a weight of 1 g in weight was used as the lower chuck. Hanged. Next, the sheet specimen was covered with a heating furnace capable of controlling the temperature, and the atmosphere temperature in the heating furnace was increased from 23 ° C. to Tf at a rate of 5 ° C./min. When the atmosphere temperature in the heating furnace reached a predetermined Tf, the heating furnace covering the sheet specimen was removed. 23 temperature sensors installed very close to the sheet specimen
Cooled to show ° C. From the displacement record of the lower chuck in this series of operations, the distance between the chucks before the start of the test is expressed as
(4 mm), the distance between the chucks at Tf is La, the distance between the chucks after cooling down to 23 ° C. by a temperature sensor provided in the vicinity of the sheet specimen is Lb, and the TMA temperature decreasing process using the following equation. Was calculated. S = [(Lb-L) / La] / (Tf-23) (/
C) Regarding Tf, a molding test described later was carried out in advance to confirm a molding temperature (a preheating plate temperature) at which a pocket having a desired shape was formed, and the temperature was defined as Tf. The measurement was performed in the MD direction of the sheet. (2) Determination of moldable temperature (Tf) Blister pack molding machine (FBP-M) manufactured by CKD Corporation
Using 2), increase the molding temperature from 130 ° C. to 2 ° C. in 15 increments.
The sheet was molded at each molding temperature while changing the temperature to 0 ° C. For molding, a pocket with a shape of bottom φ10 mm, top φ9 mm, and depth 4.1 mm is formed in 10 pieces per shot.
This was performed using a mold having two pockets. Plug temperature 13
0 ℃, in a plug pressing 5kg / mm ^2, 50 shots /
The sheet was plug-assisted and pressure-formed at a speed of minutes. The moldable temperature (Tf) was determined based on the ability to follow the mold (mold followability), the uneven appearance of the top of the pocket, and the thickness of the top. The mold followability and the appearance unevenness of the top were visually evaluated by sensory evaluation, and the thickness unevenness of the top was measured using a dial gauge. The molding temperature at which the pocket was formed well was defined as Tf. In addition, when the temperature at which the pockets were satisfactorily formed had a range, the average value of the upper and lower limits was defined as Tf. (3) Evaluation of pitch shift Using the same molding machine used to determine Tf, the raw sheet is fed, pocket forming, aluminum foil bonding, and cutting are continuously performed. The occurrence of a pitch shift trouble during the process was observed.

Example 1 A propylene homopolymer powder (MFR = 8.0, DS
Melting point main peak temperature (Tm) in C measurement = 161 to 162
C) 73.8 parts by weight, propylene / butene-1 copolymer powder (butene content = 22% by weight, Tm = 132)
C) 8.2 parts by weight, petroleum resin (Escolets 5320 manufactured by Tonex Corporation) 8.0 parts by weight, magnesium sulfate whisker (Mos Heidi-A manufactured by Ube Materials Co., Ltd .: fiber diameter = 0.5 to 1.0 μm, fiber Length = 8 to 1
5 μm) 10.0 parts by weight of 230 parts by using a twin screw extruder
To give a resin composition. This is φ65mm
230 ° C. using a T-die extruder (chill roll temperature =
(30 ° C.) to produce a 300 μm sheet. The moldable temperature (Tf) of the obtained sheet is 145 ° C., and TMA
The shrinkage rate during the cooling process is 1.3 × 10 ⁻⁴ (/ ° C.)
Met. Table 1 shows the evaluation results of the pitch shift.

Comparative Example 1 Propylene homopolymer powder (MFR = 2.5, Tm
= 158-159 ° C) and 92 parts by weight of petroleum resin (Escolets 5320 manufactured by Tonex Corporation) were granulated at 230 ° C using a twin-screw extruder to obtain a resin composition. Using a T-die extruder of φ65 mm,
A sheet of 300 μm was prepared at 0 ° C. (chill roll temperature = 30 ° C.). The moldable temperature (Tf) of the obtained sheet is 142 ° C., and the shrinkage rate in the process of cooling TMA is as follows:
It was 5.1 × 10 ⁻⁴ (/ ° C.). Table 1 shows the evaluation results of the pitch shift.

[0019]

[Table 1]

Continued on the front page (72) Inventor Koichi Yanase 5-1 Anesaki Beach, Ichihara-shi, Chiba Sumitomo Chemical Co., Ltd. (72) Inventor Yuji Kawachi 2-5-8 Higashishinagawa, Shinagawa-ku, Tokyo Sumitomo Bakelite Co., Ltd. (72) Inventor Yoshifumi Furukawa 2-5-8 Higashishinagawa, Shinagawa-ku, Tokyo Sumitomo Bakelite Co., Ltd. (72) Inventor Masaki Takeda 2-5-2-8 Higashishinagawa, Shinagawa-ku, Tokyo Sumitomo Bakelite Co., Ltd. (72) Inventor Yasuo Shimobe 2-5-8 Higashishinagawa, Shinagawa-ku, Tokyo F-term in Sumitomo Bakelite Co., Ltd. 4F071 AA20 AA39 AB23 AE17 AF61Y AH04 BC01 4J002 BA012 BB121 BB141 DE046 DE236 DG046 DH046 DJ006 FA066 FD016 GG02

Claims (4)

[Claims] 1. A shrinkage factor of 0 to 4 × 10 ⁻⁴ (/ ° C.) in a temperature decreasing process of thermomechanical analysis, comprising a polypropylene resin.
A polypropylene-based resin sheet for PTP packaging, characterized in that: 2. The polypropylene resin sheet for PTP packaging according to claim 1, comprising a resin composition comprising 100 parts by weight of a polypropylene resin and 5 to 100 parts by weight of a filler. 3. The polypropylene sheet according to claim 2, wherein the filler is magnesium sulfate whisker. 4. The polypropylene resin sheet for PTP packaging according to claim 2, wherein the resin composition further contains 1 to 10 parts by weight of a petroleum resin.