JP3327477B2 - Equipment for crystallizing spouts for preforms for polyester bottles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for crystallizing a plug portion of a preform for a polyester bottle.

[0002]

2. Description of the Related Art In recent years, polyester biaxially stretched bottles have been used for beer, juice, and the like, taking advantage of the features of excellent transparency, good gas barrier properties, high gloss, good fragrance retention, and high impact resistance.
It has begun to be widely used as a container for drinking water such as cola, tea and mineral water, and aqueous seasonings such as soy sauce and sauce. However, polyester resins, especially polyethylene terephthalate, which is widely used, has a glass transition temperature (Tg) of around 70 ° C. and is preferably filled at a high temperature. Juice, tea, sauce, etc. should be filled at a temperature of 70 ° C. or more. In this case, there is a possibility that the trunk portion and the plug portion may contract and deform.

[0003] In particular, when the plug part is contracted, the fitting with the metal lid, which is usually performed, is not successful, and the leakage of the liquid content is caused. Therefore, in such a container, the plug portion is usually crystallized in order to impart heat resistance to the plug portion, so that shrinkage does not occur in the fitting portion with the lid.

As an apparatus for crystallizing the plug portion of a polyester resin bottle, for example, Japanese Patent Publication No.
-24331. In this device,
A support is inserted into the preform, and the preform is supported at a portion other than the plug portion, and the plug portion partitioned from the other portion by the shielding plate is heated from both sides by two heaters arranged in parallel. I am trying to do it.

[0005]

However, in such a device, heat can be prevented from being radiated to the outside by the shielding plate, but sufficient heat cannot be applied to the vicinity of the flange portion. As a result, crystallization near the flange portion immediately below the shielding plate is not uniform.

Further, in the conventional apparatus, sufficient heat cannot be applied to the vicinity of the opening of the plug, which is the most accurate in preventing the leakage of the internal solution, and crystallization in this portion is insufficient. There was a problem of becoming.

As described above, in the conventional apparatus, at present, the crystallization of the plug portion is not yet sufficient, and the heat resistance is insufficient. In view of such circumstances, an object of the present invention is to provide an apparatus for crystallizing a plug portion of a preform for a polyester bottle, which can more sufficiently crystallize a plug portion of a container.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a transporting means having a continuous transporting surface, and a pusher which is rotatably supported by the transporting means at predetermined intervals and is in an inverted state. A supporting member for supporting the reform, a driving unit for rotating the supporting member by driving the conveying unit, and a stopper of the preform in the inverted state, which are disposed on both sides of the conveying area of the conveying unit. Heating means for heating from both sides, wherein the support member is disposed to be inclined at a predetermined angle in a direction perpendicular to the conveying direction of the conveying means, and one of the heating means is the inclined preform. And the other heating means is arranged near the flange of the preform.

[0009]

According to the above construction, by arranging the support member so as to be inclined to one side, one heating means can be opposed to the flange portion of the preform to irradiate sufficient heat to this flange portion. On the other hand, the other heating means can be arranged in the vicinity of the opening of the preform to heat this portion in a concentrated manner.

In this manner, the top surface of the plug (top)
Can be partially emphasized and heated, so that the degree of crystallinity can be made higher than the other parts, particularly only at the part at the tip entrance which comes into contact with the cap or packing.

Further, if the heating means is provided with a hood for adjusting the radiation direction of the radiant heat, the position of the heated portion can be easily adjusted. Further, if a through-hole for communicating the inside and outside of the preform is formed inside the support member, the air in the expanded preform can be released to the outside.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments shown in the drawings. FIG. 1 is a perspective view schematically showing an apparatus for crystallizing a plug portion of a polyester biaxially stretched container showing one embodiment of the present invention, and FIG. 2 is a plan view thereof.

In this apparatus 10, the chain conveyor 1 is employed as a conveying means. Are attached to the chain conveyor 1 so as to straddle a pair of double-row chains 3, 3.
... constitute a continuous transport surface A. Also,
Each of the plate members 2 at predetermined intervals among the plurality of plate members 2, 2,... Is formed with an oblique hole.

As shown in FIG. 3, a support member 4 composed of a cannon-shaped bush 5 and a rod 6 attached to the bush 5 is mounted on the plate member 2 thus formed as shown in FIG. 13 and is installed at an angle.

The support member 4 supports a preform P formed from a raw material described later. That is, the outer diameter of the bush 5 of the support member 4 is
Is slightly smaller than the inner diameter of the plug Pa, and the length of the rod 6 is substantially equal to the shaft of the preform P. Thereby, when the preform P is inserted into the bush 5, its posture is stabilized. The bush 5 has a through hole 7 formed in the axial direction thereof.
A screw hole 8 is formed at the bottom.

On the other hand, the jig 13 has a mounting plate 9 provided with a bearing at a substantially intermediate portion, and a shaft portion 11 on one side of the mounting plate 9 and a shaft portion continuous with the shaft portion 11 on the other side. 1
2 has been extended. A gear 1 is provided at the lower end of the shaft portion 12.
5 are attached.

The jig 13 thus formed is arranged in a state where the mounting plate 9 is in contact with the lower surface of the plate member 2.
The plate 2 and the mounting plate 9 are fixed by a plurality of bolts 14. At this time, the shaft portions 11 and 12 are supported rotatably with respect to the plate 2.

The support member 4 is integrally attached to the jig 13 by screwing the tip of the shaft portion 11 into the screw hole 8 of the bush 5. In this apparatus 10, the transfer surface A
A single chain 17 is installed in the same direction as the transport surface A below the lower side of FIG. The chain 17 is configured as a driving unit for the gear 15 and is disposed along the transfer area of the transfer surface A. Therefore, when the support member 4 is conveyed in the horizontal direction by the driving of the chain conveyor 1, the chain 17 and the gear 15 are engaged, and the support member 4 is conveyed while rotating.

Further, in this apparatus 10, heating means 20, 21 having hoods 22, 23 are provided so as to sandwich the support member 4 from both sides. The arrangement height of the heating means 20 is substantially the center of the plug Pa,
Has the same height as the flange portion Pb of the preform P. The arrangement height of the heating means 21 is substantially the same as the opening end Pc of the plug Pa.

Each of these heating means 20, 21 is specifically composed of a heater for emitting infrared rays. The hoods 22 and 23 are provided with an adjustment mechanism (not shown) for adjusting the radiation direction of the radiant heat. When the adjustment mechanism is adjusted, the hood rotates along an arc-shaped trajectory, and can change the heat dissipation direction.

The heating means 20 and 21 are at a temperature higher than the crystallization start temperature of the polyester, preferably 120 to 30.
It is preferable to have a heating capability capable of maintaining the ambient temperature at 0 ° C. and a function capable of adjusting the temperature to a constant.

In the apparatus 10 constructed as described above, as shown in FIG. 4, the inclination angle α of the support member 4 in the direction perpendicular to the conveying direction is preferably in the range of 5 ° to 45 °. And more preferably 15 to 20 °.

When the support member 4 is inclined at such an angle, crystallization when the preform P is heated by the heating means 20 and 21 is most preferable. Further, an air blowing means 31 is disposed downstream of the chain conveyor 1 as a conveying means, and the cooling air is appropriately blown by the blowing means 31.

The crystallization apparatus of the present invention is intended for a preform P formed from the following polyester as a raw material. [Polyethylene terephthalate] The polyethylene terephthalate resin used in the present invention is formed from a dicarboxylic acid constituent unit containing a terephthalic acid component unit and a dihydroxy constituent unit containing an ethylene glycol component unit.

This polyethylene terephthalate has 20
Up to mol% of other dicarboxylic acids and / or other dihydroxy compounds other than terephthalic acid and ethylene glycol may be copolymerized. Specifically as dicarboxylic acid used for copolymerization other than terephthalic acid,
Aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid, adipic acid, sebacic acid, azelaic acid, aliphatic dicarboxylic acids such as decanedicarboxylic acid, cyclohexanedicarboxylic acid, cyclohexane Alicyclic dicarboxylic acids such as propanedicarboxylic acid and hexahydroterephthalic acid;

Examples of the dihydroxy compound used for copolymerization other than ethylene glycol include aliphatic glycols such as trimethylene glycol, propylene glycol, tetramethylene glycol, neopentyl glycol, hexamethylene glycol and dodecamethylene glycol, and cyclohexane. Alicyclic glycols such as dimethanol, bisphenols, hydroquinone, 2,2-
And aromatic diols such as bis (4-β-hydroxyethoxyphenyl) propane.

The polyethylene terephthalate used in the present invention may contain a small amount of a structural unit derived from a polyfunctional compound such as trimesic acid, trimethylolethane, trimethylolpropane, trimethylolmethane, pentaerythritol, for example, in an amount of 2 mol% or less. May be included.

Further, the polyethylene terephthalate used in the present invention contains a small amount of structural units derived from monofunctional compounds such as benzoylbenzoic acid, diphenylsulfonemonocarboxylic acid, stearic acid, methoxypolyethylene glycol and phenoxypolyethylene glycol in a small amount of, for example, 2 mol% or less. May be included.

Such a polyethylene terephthalate can be used to form a substantially linear polyester by forming an ester bond alone or a random arrangement of the ethylene terephthalate component units and the dioxyethylene terephthalate component units. are doing. The fact that the polyethylene terephthalate is substantially linear is confirmed by the fact that the polyethylene terephthalate dissolves in o-chlorophenol.

The intrinsic viscosity [η] (measured in o-chlorophenol at 25 ° C.) of such polyethylene terephthalate is usually 0.5 to 1.5 dl / g, preferably 0.6 to 1.2 dl. / G is desirable. Further, the melting point is usually 210 ° C. to 265 ° C., preferably 220 to 260 ° C.
° C, and the glass transition temperature is usually 50 ° C.
To 120 ° C, preferably 60 to 100 ° C. [Copolyester] The copolyester used in the present invention is obtained by a co-condensation reaction between a dicarboxylic acid and a dihydroxy compound as described below.

The dicarboxylic acid which can be used to form the copolyester used in the present invention is 10 to 90 mol%, preferably 20 to 80 mol%, of terephthalic acid,
10-90 mol%, preferably 20-80 mol%, is isophthalic acid.

In the present invention, in forming the copolyester, in addition to the above-mentioned terephthalic acid and isophthalic acid as the dicarboxylic acid component, a range of not less than 1 mol%, for example, which does not impair the properties of the obtained copolyester. Other dicarboxylic acids can be used in amounts. Examples of such other dicarboxylic acids include phthalic acid, 2-methylterephthalic acid, and 2,6-naphthalene carboxylic acid.

The dihydroxy compound that can be used in the present invention is mainly ethylene glycol, but other dihydroxy compounds can be used in an amount that does not impair the properties of the obtained copolyester, for example, 1 mol% or less.

As such a dihydroxy compound,
1,3-propanediol, neopentyl glycol, cyclohexanediol, cyclohexanedimethanol, 1,
3-bis (2-hydroxyethoxy) benzene, 1,4-bis (2-hydroxyethoxy) benzene, 2,2-bis (4-β-
Hydroxyethoxyphenyl) propane, bis (4-β-
Examples thereof include dihydroxy compounds having 3 to 15 carbon atoms such as (hydroxyethoxyphenyl) sulfone.

The copolyester used in the present invention as described above has an intrinsic viscosity [η] measured in o-chlorophenol at 25 ° C. of 0.5 to 1.5 dl / g, preferably 0.1 to 1.5 dl / g.
It is desirably 6 to 1.2 dl / g. When the intrinsic viscosity [η] is 0.5 to 1.5 dl / g, mechanical strength is excellent and melt moldability is excellent.

The above-mentioned copolyester can be produced according to a conventionally known polycondensation method employed in the production of polyethylene terephthalate. The dicarboxylic acid can be supplied to the reaction system as a dicarboxylic acid, or can be supplied as a diol ester of the dicarboxylic acid.

Ethylene glycol as a dihydroxy compound can be supplied as ethylene glycol, or can be supplied to a reaction system in the form of a dihydroxy ester of dicarboxylic acid.

As the catalyst at the time of the copolycondensation, a conventionally known catalyst used in the production of polyethylene terephthalate can be used. As these catalysts, metals such as antimony, germanium, titanium or
The compound can be used. As the form of the compound, oxides, hydroxides, halides, inorganic acid salts, organic acid salts, complex salts, double salts, alcoholates, phenolates and the like are used. These catalysts can be used alone or 2
It can also be used as a mixture of more than one species. These catalysts can be supplied to the reaction system from the initial stage of the esterification reaction or transesterification reaction,
It can also be supplied to the reaction system before proceeding to the polycondensation reaction stage.

At the time of co-condensation, various additives such as an ester steel tube reaction catalyst, a diethylene glycol production inhibitor, a heat stabilizer, a light stabilizer, a lubricant, a pigment and a dye used in the production of polyethylene terephthalate are used. Can be.

As a catalyst for these transesterification reactions, metal compounds such as calcium, magnesium, lithium, zinc, cobalt and manganese can be used.
As the form of these compounds, oxides, hydroxides, halides, inorganic acid salts, organic acid salts and the like are used. Examples of the diethylene glycol inhibitor include amines such as triethylamine and tri-n-butylamine, and quaternary ammonium compounds such as tetraethylammonium hydroxide and tetrabutylammonium hydroxide. In addition, as the heat stabilizer, phosphoric acid, phosphorous acid, hypophosphorous acid, or a phosphoric acid compound such as an ester thereof can be used.

The copolyester used in the present invention is produced by a conventionally known melt polycondensation method, and in some cases, by adopting a solid polycondensation method after the melt polycondensation method.

In the above-mentioned melt polycondensation method, a so-called direct polycondensation method can be employed, and a transesterification polycondensation method can also be employed. More specifically describing the melt polycondensation method, for example, the above-mentioned dicarboxylic acid or its derivative, and glycol or
Simultaneously or sequentially with the derivative thereof, preferably 10
Esterification or transesterification at a temperature of 0 to 280 ° C. to form these initial polycondensates, which are then brought to a temperature below its melting point, preferably 200 to 300
For example, a method of performing polycondensation while stirring at a temperature of 0 ° C. in a vacuum or under the flow of an inert gas can be exemplified.

The copolyester which can be used in the present invention can also be produced by elongating the molecular weight by further solid-phase polycondensation of the copolyester obtained by the above-mentioned melt polycondensation method. . Specifically, such a solid-phase polycondensation method will be described. For example, a copolyester obtained by a melt polycondensation method is finely divided, and the fine particles are heated to a temperature lower than the melting point, preferably 180 to 2.
A method of maintaining the temperature at 40 ° C. under a vacuum or under an inert gas flow can be employed.

Further, the polyester composition containing the above-mentioned components includes a crosslinking agent, a heat stabilizer, a weather stabilizer, an antistatic agent,
Various compounding agents such as a lubricant, a release agent, an inorganic filler, a pigment dispersant, a pigment or a dye may be contained within a range not to impair the object of the present invention.

As a method for molding the preform P from the polyester to be processed by the apparatus of the present invention, any generally known method can be adopted. For example, a polyester is heated at a temperature below the softening point of the polyester under reduced pressure, in the air, or under an inert gas, for example, 50 to 150 ° C.
At a temperature of 2 ° C. to remove moisture, then melt-plasticize with an injection molding machine, inject the molten resin into a mold, and solidify. The resin temperature during injection molding is 2
20 to 350 ° C., preferably 250 to 300
It is in the range of ° C. The temperature of the mold is preferably 0 ° C.
To 50 ° C.

The operation of the crystallization apparatus 10 for crystallizing the plug of the preform P formed from the above-described raw materials will be described below. The preform P is inserted into each support member 4 in an inverted state.

At this time, the preform P is
The bottom is supported by the tip of the rod 6 and the plug Pa is supported around the bush 5. This allows
The opening Pc of the preform P is supported away from the plate material 2.

The heating means 21 is provided at the opening P of the preform P.
c. Further, the other heating means 20 is arranged near the flange portion Pb of the preform P.

In the apparatus 10 set as described above, when the chain conveyor 1 is driven, the plate members 2 are sequentially transported along the transport surface A. At this time, the preform P is transported in a posture inclined at an inclination angle α in a direction orthogonal to the transport direction.

Further, when the plate material 2 is conveyed with the driving of the chain conveyor 1, the gear 15 of the jig 13 rotates while meshing with the connecting portion of the chain 17. Therefore, the shaft portions 12 and 11 rotate, whereby the preform P rotates.

In this way, the preform P is conveyed in the conveying area of the chain conveyor 1 while rotating, along with the driving of the chain conveyor 1. In this device 10,
Since the heating means 20 and 21 are interposed in the transport direction,
The preform P is conveyed while being heated by these heating means 20 and 21. In other words, the opening P of the plug Pa
Since the heating means 21 is disposed facing c,
This part is intensively heated by the heating means 21. Also,
The vicinity of the flange portion Pb of the preform P is mainly heated by the other heating means 20. Further, the plug portion in the middle portion is also heated by radiant heat from the upper and lower heating means 20 and 21.

When the preform P is heated in this way, heat is prevented from being released to the outside by the hoods 22 and 23, and radiant heat is radiated around the preform P. Therefore, the heat flow around the plug portion is good, and the desired crystallization at the plug portion is promoted.

As described above, according to the present apparatus, not only the intermediate portion of the plug Pa, but also the opening Pc and the flange Pb
However, a uniform crystal structure with high heat resistance can be obtained.
Further, when the preform P is heated by the heating means 20 and 21, air may expand in the preform P and the internal pressure may increase. However, since the through-hole 7 is formed in the support member 4, Air with pressure can be released outward from the through hole 7.

Further, according to the present apparatus, when the preform P having the heated plug Pa reaches the downstream area of the conveying area, the preform P is cooled by the air from the jetting means 31 sequentially. The preform P having the plug portion crystallized in this way can be subsequently biaxially stretched by a known biaxial stretch blow molding machine to produce a container. The stretching temperature is
If the polyester is polyethylene terephthalate,
The stretching ratio is 90 to 130 ° C., and the stretching ratio is 9 times or more, preferably 10 to 15 times, in terms of the area stretching ratio, where (longitudinal stretching ratio × lateral stretching ratio = area ratio).

In the polyester biaxially stretched bottle produced in this manner, even if the container is filled with high-temperature tea of about 70 ° or the like, the plug Pa can prevent deformation as described above. Since it is crystallized with a gradient, it does not deform.

Further, the metal lid is also tightly engaged, so that the content liquid does not leak. As mentioned above, although one Example of this invention was described, this invention is not limited to the said Example, Various modifications are possible based on the technical idea of this invention.

For example, the support member 4 in the above embodiment is used.
Instead, for example, as shown in FIG. 5, a support member 28 provided with an annular body 27 at an intermediate portion of the rod 6 may be used. If such a supporting member 28 is adopted, even when the preform P is heated by the heating means 20 and 21, even if the preform P is affected by the heat of partially deforming the preform P, the intermediate part is not removed from the inside. Since it can be supported, deformation is unlikely to occur.

Therefore, there is no danger that the preform P will lose its uniformity. Further, in the above embodiment, the chain 17 meshing with the gear 15 is exemplified as the driving means for rotating the support member 4 on its own axis, but the driving means may be other means such as a rack. Further, the means for inclining the support member 4 is not particularly limited to the embodiment.

[0059]

As described above, in the polyester container in which the mouth is crystallized by the apparatus of the present invention, the spout is crystallized so as to be suitable for the purpose, that is, partially changed. Has sufficient heat resistance. Therefore, shrinkage or deformation does not occur even if a high-temperature liquid is filled. In addition, since only the mouth portion is crystallized, the subsequent stretching step is performed smoothly, and the proportion of defective stretched products is reduced.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of an apparatus for crystallizing a plug portion of a preform for a polyester bottle according to the present invention.

FIG. 2 is a schematic plan view of FIG.

FIG. 3 is a partially cutaway front view of a support member employed in the present embodiment.

FIG. 4 is a cross-sectional view of a support member that supports a preform.

FIG. 5 is a front view showing a modification of the support member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chain conveyor (conveying means) 4, 28 Support member 7 Through-hole 17 Chain (driving means) 20, 21 Heating means 22, 23 Hood A Conveying surface P Preform Pa Plug part Pb Flange part Pc Opening

Claims (4)

(57) [Claims] 1. A transport unit having a continuous transport surface, a support member rotatably supported by the transport unit at predetermined intervals, and supporting an inverted preform, and transporting the support member. A driving unit that rotates on the basis of the driving of the unit, and a heating unit that is disposed on both sides of the conveyance area of the conveyance unit and that heats the plug portion of the inverted preform from both sides. The heating means is disposed at a predetermined angle in a direction orthogonal to the conveying direction of the conveying means, and one of the heating means is arranged so as to face the vicinity of the opening of the inclined preform, and the other is heated. An apparatus for crystallizing a plug portion of a preform for a polyester bottle, wherein the means is disposed near a flange portion of the preform. 2. An angle between the support member and a vertical direction is 5 degrees.
2. The apparatus for crystallizing a plug part of a preform for a polyester bottle according to claim 1, wherein the angle is from 45 ° to 45 °. 3. 3. A through-hole is formed in the support member, one end of the through-hole is opened in the preform, and the air in the preform is exposed to the outside air through the other end of the through-hole. 2. The apparatus for crystallizing a plug part of a preform for a polyester bottle according to claim 1, wherein the apparatus can be opened. 4. The apparatus according to claim 1, wherein said heating means includes a hood capable of adjusting a radiation direction of radiant heat.
4. The apparatus for crystallizing a plug portion of a preform for a polyester bottle according to claim 1.