JP2005059932A - Polypropylene-based sheet for ptp package - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a PP sheet capable of preventing a PTP from curling which may cause troubles in appearance or collection and pillow-packaging on an automatic packaging line, improving moistureproofness, and fully satisfying other characteristics required for PTP-packaging such as a forming temperature range and transparency. <P>SOLUTION: The polypropylene-based sheet for PTP-packaging is made of a polypropylene-based resin composition including acryl modified polytetrafluoroethyelene of 0.1-5 pts.wt. added to a polypropylene-based resin of 100 pts.wt. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a polypropylene-based sheet for press-through pack (hereinafter referred to as PTP) packaging, which is generally used for solid agent packaging in the field of pharmaceutical packaging.

  In the field of pharmaceutical packaging, PTP packaging, which is commonly used for packaging solid tablets such as tablets, capsules, etc., has a sheet made mainly of rigid polyvinyl chloride in terms of transparency, formability, waist strength, and cost. It is a package that is used as a material, molded into a pocket shape, filled with solid agents (tablets, capsules, etc.), and sealed with a lid made of aluminum foil. Practical use in the first half of the 1960s It has become widespread.

  Most of the contents of tablets and capsules are altered or deformed by moisture absorption. Secondary packaging such as pillow wrapping is applied to the composite film containing aluminum foil, or a hard vinyl chloride sheet is used. Although this has been dealt with by using a sheet in which polyvinylidene chloride resin having excellent moisture resistance is combined by coating or the like, these are expensive and have a problem in cost. In addition, there is an increasing tendency to refrain from polyvinyl chloride resin due to the problem of disposal due to generation of dioxins. Therefore, recently, a sheet made of a polypropylene resin, which is an olefin resin, has come to be used as a sheet for PTP packaging with attention paid to moisture proofing, low cost and easy processing.

However, as a sheet for PTP packaging, polypropylene is inferior in impact resistance (especially at low temperatures) and has a narrow molding condition range as compared with polyvinyl chloride. Trouble occurred in pillow packaging, and the machine stopped. These problems are caused by the fact that polypropylene is a crystalline resin. Attempts have been made to increase the degree of crystallinity of polypropylene in order to improve curling. Further, although a method such as annealing the sheet was performed, the formability was remarkably deteriorated and the sheet was not able to withstand actual use. In order to improve moldability, a method of suppressing the crystallinity by adding a petroleum resin to a polypropylene homopolymer has been taken, but this method has a further disadvantage that impact resistance is significantly impaired. It was. In order to improve the impact resistance, a method of adding a thermoplastic elastomer (TPE) (see Patent Document 1) has been taken, but the impact resistance is improved as the amount of TPE added increases, but at the same time, rigidity and moisture resistance are improved. There was a problem that the performance decreased. Furthermore, an attempt has been made to rapidly cool at the time of sheeting to suppress the crystallinity to improve the moldability (see Patent Document 2). However, with this method, the waist of the sheet is remarkably weak and cannot be actually used.
In addition, an attempt has been made to laminate a non-crystalline polyolefin excellent in mechanical strength, moldability, transparency, dimensional stability, and moisture resistance with a crystalline polyolefin to supplement impact resistance to form a composite sheet. (Refer to Patent Document 3) Although good results are obtained in both curling properties and moldability, the cost of amorphous polyolefin is high, so there is a problem in terms of cost as a substitute for polyvinyl chloride.
Thus, at present, it is difficult to bring out excellent mechanical properties and characteristics as low as polyvinyl chloride only from the surface of the material of the PTP package.

  Therefore, the following improvement measures have been taken from the viewpoint of the PTP packaging apparatus with emphasis on the curl property among the above problems. As the conventional heating plate, a heating plate of a type in which the front surface of the sheet or most of the heating plate is heated is used. In this form, there is no problem in moldability, but when a crystalline resin such as PP is used for the bottom material sheet in curling property, curling becomes large, causing troubles in the transport section and pillow packaging section in the PTP packaging line. Therefore, as measures for improvement, there are a method using a pinpoint heating method in which only a heating part of a heating plate is formed, a method of correcting curl with a reverse warp device (see Patent Document 4), and the like. Of these, the pin-point heating method is particularly effective and is good not only for curling properties immediately after molding but also with time. However, the pinpoint heating method has a problem in moldability because the heating area is narrow and the number of times of heating is smaller than in the conventional method. Therefore, measures such as reducing the line speed are taken, but as a result, productivity is lowered.

JP-A-8-157659 JP-A-1-171833 Japanese Patent No. 3043559 Japanese Patent Application Laid-Open No. 5-201408

  The object of the present invention is to achieve the above-mentioned problems, in particular, excellent curling properties, improved moisture resistance, and sufficient PTP for properties required for other PTP packaging such as molding temperature width and transparency. Providing polypropylene sheet for use.

  The present invention comprises a polypropylene-based sheet for PTP packaging, comprising a polypropylene-based resin composition in which 0.1 to 5 parts by weight of acrylic-modified polytetrafluoroethylene is added to 100 parts by weight of a polypropylene-based resin. It is.

  According to the present invention, it is possible to suppress the curling of PTP, which causes troubles in appearance or automatic packaging line accumulation and pillow packaging, and to improve the moisture resistance, and further, other PTPs such as molding temperature width and transparency It is possible to obtain a polypropylene-based PTP sheet having sufficient properties required for packaging.

  The polypropylene resin used in the polypropylene sheet for PTP packaging according to the present invention is a homopolymer of propylene or a copolymer of propylene mainly composed of propylene and other monomer components, and is preferably a polypropylene resin. Examples of such polymers include propylene homopolymers, random copolymers or block copolymers of propylene and ethylene, random copolymers or block copolymers of propylene and α-olefins such as butene, pentene, hexene, and heptene. Coalescence is mentioned. In particular, a homopolymer of propylene and an ethylene-propylene random copolymer having an ethylene content of 1% by weight or less are preferable in terms of curling and moisture resistance. In addition, a polypropylene resin may be used alone or in combination of two or more.

  The addition amount of the acrylic modified polytetrafluoroethylene used in the present invention is 0.1 to 5 parts by weight, preferably 0.3 to 1 part by weight, based on 100 parts by weight of the polypropylene resin. If the amount of acrylic-modified polytetrafluoroethylene is less than 0.1 parts by weight, the effect on moisture resistance and curling properties will be insufficient, and if it exceeds 5 parts by weight, processability will be poor and ejection during extrusion will be unstable. In addition, the sheet appearance is impaired.

Furthermore, the PTP packaging polypropylene resin of the present invention preferably contains a petroleum resin for the purpose of improving processability and achieving high water vapor barrier properties. Petroleum resins include synthetic resin-based petroleum resins and natural product-based petroleum resins. In the present invention, synthetic resin-based petroleum resins are preferred. Synthetic resin-based petroleum resins include aliphatic hydrocarbon resin-based, aromatic hydrocarbon resin-based, alicyclic saturated hydrocarbon resin-based, and copolymerized systems. Among them, from the viewpoint of odor and transparency, An alicyclic saturated hydrocarbon resin-based petroleum resin is preferred.
The content of the petroleum resin in the polypropylene resin of the present invention is usually preferably 1 to 10% by weight. If the content of the petroleum resin is less than 1% by weight, it is difficult to obtain sufficient processability and a water vapor barrier effect, and if it exceeds 10% by weight, the amount of residual monomers and low molecular weight compounds extracted with n-heptane increases. This is not preferable because it will not comply with the Ministry of Health and Welfare Notification No. 20.

  In addition to polypropylene resins, homopolymers composed of α-olefins such as ethylene, butene, pentene, hexene, heptene, ethylene and butene, pentene, hexene, heptene, etc., as long as the effects of the present invention are not significantly impaired Α-olefin copolymer, cyclic olefin polymer, ethylene-methyl methacrylate copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-vinyl acetate-methyl methacrylate copolymer Copolymers of carboxylic acid derivatives having an ethylenically unsaturated bond, such as coalescence, and ethylene, polyvinyl alcohol, polyvinyl acetate, polycarbonate, polyester, polyamide, polystyrene, polymethyl methacrylate, thermoplastic elastomer, rubber, hydrogenated rubber Polymers such as You may contain. The content of the polymer other than the polypropylene resin is usually 50% by weight or less, preferably 100% by weight when the total amount of the resin components in the resin composition (that is, the polypropylene resin and the other polymer) is 100% by weight. Is 30% by weight or less, more preferably 20% by weight or less. These polymers are preferably those having a refractive index difference of 0.04 or less with a polypropylene resin at 23 ° C., particularly preferably 0.03 or less, and particularly preferably 0.02 or less. .

  Furthermore, as long as the effects of the present invention are not significantly impaired, the polypropylene resin is an antioxidant, ultraviolet absorber, light stabilizer, lubricant, antiblocking agent, antistatic agent, surfactant, dye, pigment, Agents, plasticizers, crystal nucleating agents, and the like.

  The resin composition uses a widely used method, that is, a batch kneader such as a Banbury mixer, a kneader, or a roll, or a continuous kneader such as a single screw extruder, a twin screw extruder, or a calender roll. It can be manufactured by a method. Among these, it is preferable to use a twin-screw kneader equipped with a vacuum deaeration device.

  The polypropylene resin sheet for PTP packaging of the present invention can be produced by forming the resin composition obtained as described above into a sheet form by T-die extrusion or a conventional method such as calendaring. The thickness of the sheet is usually in the range of 0.16 to 0.6 mm, and preferably in the range of 0.25 to 0.35 mm.

  The polyprene resin sheet for PTP packaging of the present invention is further molded into a desired shape by thermoforming or the like and used for PTP packaging.

Hereinafter, the present invention will be described in more detail with reference to examples. However, these are merely examples, and the present invention is not limited to these examples.
<Example 1>

Propylene homopolymer pellets as a polypropylene resin (MFR = 2.3 g / 10 min, Tm = 158 to 159 ° C., refractive index at 23 ° C. = 1.50) 82.8 parts by weight, propylene / butene-1 copolymer Combined pellet (butene-1 content = 20 wt%, Tm = 132 ° C, refractive index at 23 ° C = 1.50), 9.2 parts by weight, petroleum resin (Scoretz 5320 manufactured by Tonex Co., Ltd., refraction at 23 ° C (Rate = 1.55) A total of 100 parts by weight of 8.0 parts by weight is used to add 0.5 parts by weight of acrylic-modified polytetrafluoroethylene (Mettablen A-3000 manufactured by Mitsubishi Rayon Co., Ltd.) using a twin screw extruder. Vent granulation was performed at 0 ° C. to obtain a resin composition. This was molded into a 300 μm sheet at 230 ° C. (chill roll temperature = 30 ° C.) using a 50 mm T-die extruder. The evaluation results of the obtained sheet are shown in Table 1.
<Comparative Example 1>

Propylene homopolymer pellets as a polypropylene resin (MFR = 2.3 g / 10 min, Tm = 158 to 159 ° C., refractive index at 23 ° C. = 1.50) 82.8 parts by weight, propylene / butene-1 copolymer For a total of 100 parts by weight of 9.2 parts by weight of coalescent pellets (butene-1 content = 20% by weight, Tm = 132 ° C., refractive index at 23 ° C. = 1.50) 5320, refractive index at 23 ° C. = 1.55) 8.0 parts by weight was vent granulated at 230 ° C. using a twin screw extruder to obtain a resin composition. This was molded into a 300 μm sheet at 230 ° C. (chill roll temperature = 30 ° C.) using a 50 mm T-die extruder. The evaluation results of the obtained sheet are shown in Table 1.
<Comparative example 2>

Propylene homopolymer pellets as a polypropylene resin (MFR = 2.3 g / 10 min, Tm = 158 to 159 ° C., refractive index at 23 ° C. = 1.50) 82.8 parts by weight, propylene / butene-1 copolymer Combined pellet (butene-1 content = 20 wt%, Tm = 132 ° C, refractive index at 23 ° C = 1.50), 9.2 parts by weight, petroleum resin (Scoretz 5320 manufactured by Tonex Co., Ltd., refraction at 23 ° C (Rate = 1.55) A total of 100 parts by weight of 8.0 parts by weight, 0.05 parts by weight of acrylic-modified polytetrafluoroethylene (Mitsubrene A-3000 manufactured by Mitsubishi Rayon Co., Ltd.) was added using a twin screw extruder. Vent granulation was performed at 0 ° C. to obtain a resin composition. This was molded into a 300 μm sheet at 230 ° C. (chill roll temperature = 30 ° C.) using a 50 mm T-die extruder. The evaluation results of the obtained sheet are shown in Table 1.
<Comparative Example 3>

  Propylene homopolymer pellets as a polypropylene resin (MFR = 2.3 g / 10 min, Tm = 158 to 159 ° C., refractive index at 23 ° C. = 1.50) 82.8 parts by weight, propylene / butene-1 copolymer Combined pellet (butene-1 content = 20 wt%, Tm = 132 ° C, refractive index at 23 ° C = 1.50), 9.2 parts by weight, petroleum resin (Scoretz 5320 manufactured by Tonex Co., Ltd., refraction at 23 ° C (Ratio = 1.55) 8 parts by weight of acrylic modified polytetrafluoroethylene (Metablen A-3000 manufactured by Mitsubishi Rayon Co., Ltd.) at 230 ° C. using a twin screw extruder with respect to a total of 100 parts by weight of 8.0 parts by weight. Vent granulation was performed to obtain a resin composition. This was molded into a 300 μm sheet at 230 ° C. (chill roll temperature = 30 ° C.) using a 50 mm T-die extruder. The evaluation results of the obtained sheet are shown in Table 1.

The evaluation method in the present invention is as follows.
PTP moldability: In a PTP molding machine (FBP-M2 manufactured by CKD), molded using biofermin tablet mold (diameter 10mmφ, depth 5mm), pinpoint heating plate, molding temperature range is molding The molding temperature range was determined by comprehensive evaluation of the mold followability to the mold and the appearance unevenness of the top of the pocket, the thickness of the top, corner and side portions. The mold followability and the appearance unevenness of the top were visually evaluated, and the thickness of the top, corner, and side portions were determined by measurement with a dial gauge. The uniformity of the thickness distribution of the molding pocket was divided into two by a cutter blade and judged by a cross-sectional photograph. The molding temperature range evaluated in this way is better as it is wider, but considering the heating temperature variation at the time of molding, a molding temperature range of 4 ° C. or more was considered good.
Curl properties after punching: Molded under the best conditions in the above-mentioned molding temperature range evaluation, sealed with aluminum foil and 210 ° C without filling the contents, and put a slitter at 130 ° C,
A molded product punched into a width of 37 mm, a length of 94 mm, and a corner of 5 mmR was placed on a flat surface, and the warpage of the molded product immediately after punching and after 2 days was measured. About 10 molded products
Four locations of the molding pocket angle were measured and the average value was obtained and evaluated. Aluminum foil is hard aluminum foil
The thing which apply | coated maleated polypropylene 5micrometer to 20 micrometers was used. The curl height should be low, but there is a problem such as smooth conveyance without any curling. Therefore, in the punching size used in the examples of the present invention, the lower limit is 1 mm or more, and the upper limit is If it was 3 mm or less immediately after and 2 mm or less after 2 days, it was judged as good without any problem.
Transparency: The total light transmittance and internal haze of the sheet were measured based on JIS-K-7105. The higher the total light transmittance and the lower the internal haze, the better the transparency. Here, if the total light transmittance is lower than 85% and the internal haze is higher than 40%, the transparency is deteriorated, the filled medicine is difficult to see, the cause of malfunction of the defect detector, and the aluminum printing becomes difficult to see. Problem arises. Therefore, the total light transmittance is 85% or more and the internal haze is 40% or less.
Moisture proof: A sample was stored in a constant temperature and humidity layer of 40 ° C. and 90%, and measured based on the cup method of JIS-Z-0208. The required moisture resistance is a PP-based sheet, and 0.60 g / m ² · D or less was considered good.

  According to the present invention, it is possible to suppress the curling of PTP, which causes troubles in appearance or automatic packaging line accumulation and pillow packaging, and to improve the moisture resistance, and further, other PTPs such as molding temperature width and transparency It is possible to obtain a polypropylene-based PTP sheet having sufficient properties required for packaging.

Claims (1)

  A polypropylene-based sheet for PTP packaging, comprising a polypropylene-based resin composition in which 0.1 to 5 parts by weight of acrylic-modified polytetrafluoroethylene is added to 100 parts by weight of a polypropylene-based resin.