KR102667779B1 - Method and system for manufacturing sheet for polypropylene container - Google Patents

Abstract

Disclosed herein are methods and systems for manufacturing polypropylene container sheets. The sheet manufactured by the method and system according to one embodiment exhibits excellent quality by extruding and molding raw materials mixed at a specific mixing ratio under specific temperature conditions and has the advantage of being suitable for manufacturing polypropylene containers.

Description

Method and system for manufacturing polypropylene container sheets {METHOD AND SYSTEM FOR MANUFACTURING SHEET FOR POLYPROPYLENE CONTAINER}

The examples below relate to a method and system technology for manufacturing polypropylene container sheets.

In general, food packaging containers are demanding high-performance, high-quality products due to the increase in consumer national income and changes in awareness of food hygiene, and rapid changes in climate and seasonal factors such as global warming and consumers' food preferences are subject to immediate changes. With the diversification of cooked and processed foods and the characteristics of packaging objects such as fruit, fish, and meat, packaging methods and demand patterns for various foods are rapidly changing.

As these food packaging methods and demand patterns change, food packaging containers go beyond the concept of simple packaging for food and respond to the characteristics of the packaging object to supply fresh food and food by increasing the freshness retention period of food. It has functionality such as antibacterial, deodorizing, and antioxidant properties to reduce waste, secure heat resistance for instant processing and packaging of high-temperature foods, and reduce environmental pollution due to disposal of packaging containers, and various instant processed foods and high-temperature foods. There is an urgent need for the development of food packaging containers that secure heat resistance for food packaging and are eco-friendly when disposing of the packaging containers.

Products commonly used as food containers are divided into foaming and non-foaming types. Foaming products are made by mixing polystyrene with foaming gas and extruding it. They have the advantage of being able to maintain a relatively thick shape, maintain their shape, provide good insulation, and have high price competitiveness, but they have the disadvantage of detecting harmful substances at high temperatures. The non-foaming method is a method of manufacturing heat-stable polypropylene in the form of a film, which has the advantage of having a low dimensional change rate at high temperatures and no harmful substances detected.

Republic of Korea Patent Publication No. 10-2021-0036067

The embodiments are intended to provide a method and system for manufacturing excellent quality sheets suitable for manufacturing polypropylene containers by extruding and molding raw materials mixed at a specific mixing ratio under specific temperature conditions.

One embodiment is a method of manufacturing a polypropylene container sheet,

A raw material mixing step of mixing homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer at a weight ratio of 20 to 40:20 to 40:30 to 50;

The mixed raw materials are placed in a primary cylinder at 190 to 210°C, a secondary cylinder at 210 to 230°C, a 3rd to 6th cylinder at 220 to 240°C, a cylinder head at 240 to 260°C, and a T- at 220 to 240°C. A melt extrusion step of melting and extruding by passing through a die;

A cold pressing step of compressing the extruded raw material into a sheet by passing it through three primary cooling rollers arranged in the longitudinal direction and two secondary cooling rollers arranged in the longitudinal direction;

A forming step of cutting both ends of the sheet according to a predetermined size while moving the pressed sheet through a plurality of horizontal rollers arranged in the transverse direction; and

It includes a winding step of winding the cut sheet on a winder,

The temperature of the secondary cylinder is higher than the temperature of the primary cylinder, the temperature of the 3rd to 6th cylinders is higher than the temperature of the secondary cylinder, and the temperature of the cylinder head is higher than that of the 3rd to 6th cylinders. higher than the temperature, and the temperature of the T-dice is lower than the temperature of the cylinder head,

The upper and central rollers of the three primary cooling rollers are at a temperature of 20 to 40° C. and the lower rollers are at a temperature of 30 to 50° C., the temperature of the lower roller is higher than that of the upper and central rollers, and the temperature of the two secondary cooling rollers is higher than that of the upper and central rollers. is 10 to 30°C, and the temperature of the secondary cooling roller is lower than that of the primary cooling roller,

The first cylinder, second cylinder, and third to sixth cylinders are preheated to 250 to 260 ° C.

Provides a method.

In another embodiment, in the raw material mixing step,

Both end pieces of the sheet cut in the forming step are mixed with the homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer,

The homopolypropylene, polypropylene-ethylene copolymer, polyethylene-α-olefin copolymer, and both end pieces of the cut sheet are mixed in a weight ratio of 10 to 30:10 to 30:10 to 30:30 to 50. Provides a method to do so.

In another embodiment, before the forming step,

A method is provided, further comprising the step of applying a silicone release agent to one surface of the pressed sheet.

Another embodiment is a system for manufacturing a polypropylene container sheet by the above method, comprising:

A raw material mixing section for mixing homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer at a weight ratio of 20 to 40:20 to 40:30 to 50;

The raw materials mixed in the raw material mixing section are mixed into a primary cylinder at 190 to 210°C, a secondary cylinder at 210 to 230°C, a 3rd to 6th cylinder at 220 to 240°C, a cylinder head at 240 to 260°C, and a cylinder head at 220 to 240°C. An extrusion unit that melts and extrudes by passing it through a T-die at ℃;

A pressing unit that compresses the raw material extruded from the extrusion unit into a sheet by passing the raw material through three primary cooling rollers arranged in the longitudinal direction and two secondary cooling rollers arranged in the longitudinal direction;

a release agent application unit that applies a silicone release agent to one surface of the sheet pressed in the compression unit;

a molding unit that cuts both ends of the sheet to a predetermined size while moving the sheet coated with the release agent through a plurality of horizontal rollers arranged in the transverse direction; and

It includes a winding unit that winds the sheet cut from the forming unit onto a winder,

The temperature of the secondary cylinder is higher than the temperature of the primary cylinder, the temperature of the 3rd to 6th cylinders is higher than the temperature of the secondary cylinder, and the temperature of the cylinder head is higher than that of the 3rd to 6th cylinders. higher than the temperature, and the temperature of the T-dice is lower than the temperature of the cylinder head,

The upper and central rollers of the three primary cooling rollers are at a temperature of 20 to 40° C. and the lower rollers are at a temperature of 30 to 50° C., the temperature of the lower roller is higher than that of the upper and central rollers, and the temperature of the two secondary cooling rollers is higher than that of the upper and central rollers. is 10 to 30°C, and the temperature of the secondary cooling roller is lower than that of the primary cooling roller,

The first cylinder, second cylinder, and third to sixth cylinders are preheated to 250 to 260 ° C.

Provides a system.

In another embodiment, the raw material mixing unit,

Mixing both end pieces of the sheet cut from the molding unit with the homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer,

The homopolypropylene, polypropylene-ethylene copolymer, polyethylene-α-olefin copolymer, and both end pieces of the cut sheet are mixed in a weight ratio of 10 to 30:10 to 30:10 to 30:30 to 50. Provides a system that does this.

Examples can provide excellent quality sheets suitable for manufacturing polypropylene containers by extruding and molding raw materials mixed at a specific mixing ratio under specific temperature conditions.

1A and 1B are process diagrams briefly showing a method of manufacturing a polypropylene container sheet according to an embodiment.
Figure 2 shows the configuration of a manufacturing system for a polypropylene container sheet according to an embodiment.
Figure 3 schematically shows the configuration of the pressing portion of the manufacturing system for polypropylene container sheets according to one embodiment.
Figure 4 schematically shows the configuration of the release agent application portion of the manufacturing system for polypropylene container sheets according to one embodiment.

Hereinafter, embodiments will be described in detail with reference to the attached drawings. However, various changes can be made to the embodiments, so the scope of the patent application is not limited or limited by these embodiments. It should be understood that all changes, equivalents, or substitutes for the embodiments are included in the scope of rights.

Specific structural or functional descriptions of the embodiments are disclosed for illustrative purposes only and may be modified and implemented in various forms. Accordingly, the embodiments are not limited to the specific disclosed form, and the scope of the present specification includes changes, equivalents, or substitutes included in the technical spirit.

Terms such as first or second may be used to describe various components, but these terms should be interpreted only for the purpose of distinguishing one component from another component. For example, a first component may be named a second component, and similarly, the second component may also be named a first component.

When a component is referred to as being “connected” to another component, it should be understood that it may be directly connected or connected to the other component, but that other components may exist in between.

The terms used in the examples are for descriptive purposes only and should not be construed as limiting. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by a person of ordinary skill in the technical field to which the embodiments belong. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless explicitly defined in the present application, should not be interpreted in an ideal or excessively formal sense. No.

The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and will be implemented in various different forms. The present embodiments only serve to ensure that the disclosure of the present invention is complete and that common knowledge in the technical field to which the present invention pertains is not limited. It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

In the embodiments of the present invention, unless otherwise defined, all terms used herein, including technical or scientific terms, are the same as those commonly understood by a person of ordinary skill in the technical field to which the present invention pertains. It has meaning. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless clearly defined in the embodiments of the present invention, have an ideal or excessively formal meaning. It is not interpreted as

The shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining embodiments of the present invention are illustrative, and the present invention is not limited to the matters shown. Additionally, in describing the present invention, if it is determined that a detailed description of related known technologies may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. When 'includes', 'has', 'consists of', etc. mentioned in the specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, the plural is included unless specifically stated otherwise.

When interpreting a component, it is interpreted to include the margin of error even if there is no separate explicit description.

Each feature of the various embodiments of the present invention can be partially or fully combined or combined with each other, and as can be fully understood by those skilled in the art, various technical interconnections and operations are possible, and each embodiment may be implemented independently of each other. It may be possible to conduct them together due to a related relationship.

In one aspect, the present invention may relate to a method of manufacturing a sheet for a polypropylene container.

1A and 1B are process diagrams briefly showing a method of manufacturing a polypropylene container sheet according to an embodiment.

As shown in Figure 1A, in one embodiment, the method comprises homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer in a weight ratio of 20 to 40:20 to 40:30 to 50. Mixing raw material mixing step; The mixed raw materials are mixed into a cylinder consisting of a primary cylinder at 190 to 210°C, a secondary cylinder at 210 to 230°C, and a 3rd to 6th cylinder at 220 to 240°C, a cylinder head at 240 to 260°C, and a cylinder at 220 to 240°C. A melt extrusion step of melting and extruding by passing through a T-die; A cold pressing step of compressing the extruded raw material into a sheet by passing it through three primary cooling rollers arranged in the longitudinal direction and two secondary cooling rollers arranged in the longitudinal direction; A forming step of cutting both ends of the sheet according to a predetermined size while moving the pressed sheet through a plurality of horizontal rollers arranged in the transverse direction; And it may include a winding step of winding the cut sheet on a winder.

In one embodiment, in the raw material mixing step, both end pieces of the sheet cut in the forming step may be mixed with the homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer.

In one embodiment, the mixing ratio of the homopolypropylene, polypropylene-ethylene copolymer, polyethylene-α-olefin copolymer, and both end pieces of the cut sheet is 10 to 30:10 to 30:10 to 30 by weight. : Can be 30 to 50.

That is, the sheet pieces cut in the forming step can be reused by mixing them together in the raw material mixing step.

In one embodiment, the temperature of the primary cylinder may be 190 to 210°C, and more specifically, the temperature of the primary cylinder may be 190°C or higher, 191°C or higher, 192°C or higher, 193°C or higher, or 194°C or higher. , 195℃ or higher, 196℃ or higher, 197℃ or higher, 198℃ or higher, 199℃ or higher, 200℃ or higher, 201℃ or higher, 202℃ or higher, 203℃ or higher, 204℃ or higher, 205℃ or higher, 206℃ or higher, 207 It may be ℃ or higher, 208 ℃ or higher, or 209 ℃ or higher, and the temperature of the primary cylinder is 210 ℃ or lower, 209 ℃ or lower, 208 ℃ or lower, 207 ℃ or lower, 206 ℃ or lower, 205 ℃ or lower, 204 ℃ or lower, 203℃ or lower, 202℃ or lower, 201℃ or lower, 200℃ or lower, 199℃ or lower, 198℃ or lower, 197℃ or lower, 196℃ or lower, 195℃ or lower, 194℃ or lower, 193℃ or lower, 192℃ or lower, or 191℃ It may be below. Preferably, the temperature of the primary cylinder may be 200°C.

In one embodiment, the temperature of the secondary cylinder may be 210 to 230°C, and more specifically, the temperature of the secondary cylinder may be 210°C or higher, 211°C or higher, 212°C or higher, 213°C or higher, or 214°C or higher. , 215℃ or higher, 216℃ or higher, 217℃ or higher, 218℃ or higher, 219℃ or higher, 220℃ or higher, 221℃ or higher, 222℃ or higher, 223℃ or higher, 224℃ or higher, 225℃ or higher, 226℃ or higher, 227 It may be ℃ or higher, 228 ℃ or higher, or 229 ℃ or higher, and the temperature of the secondary cylinder is 230 ℃ or lower, 229 ℃ or lower, 228 ℃ or lower, 227 ℃ or lower, 226 ℃ or lower, 225 ℃ or lower, 224 ℃ or lower, 223℃ or lower, 222℃ or lower, 221℃ or lower, 220℃ or lower, 219℃ or lower, 218℃ or lower, 217℃ or lower, 216℃ or lower, 215℃ or lower, 214℃ or lower, 213℃ or lower, 212℃ or lower, or 211℃ or lower It may be below. Preferably, the temperature of the secondary cylinder may be 220°C.

In one embodiment, the temperature of the 3rd to 6th cylinders may be 220 to 240°C, and more specifically, the temperature of the 3rd to 6th cylinders may be 220°C or higher, 221°C or higher, 222°C or higher, 223°C or higher. ℃ or higher, 224℃ or higher, 225℃ or higher, 226℃ or higher, 227℃ or higher, 228℃ or higher, 229℃ or higher, 230℃ or higher, 231℃ or higher, 232℃ or higher, 233℃ or higher, 234℃ or higher, 235℃ or higher , may be 236°C or higher, 237°C or higher, 238°C or higher, or 239°C or higher, and the temperature of the 3rd to 6th cylinders is 240°C or lower, 239°C or lower, 238°C or lower, 237°C or lower, and 236°C or lower. , 235℃ or lower, 234℃ or lower, 233℃ or lower, 232℃ or lower, 231℃ or lower, 230℃ or lower, 229℃ or lower, 228℃ or lower, 227℃ or lower, 226℃ or lower, 225℃ or lower, 224℃ or lower, 223 It may be ℃ or lower, 222℃ or lower, or 221℃ or lower. Preferably, the temperature of the 3rd to 6th cylinders may be 230°C.

In one embodiment, the temperature of the seal head may be 240 to 260°C, and more specifically, the temperature of the cylinder head may be 240°C or higher, 241°C or higher, 242°C or higher, 243°C or higher, 244°C or higher, Above 245℃, above 246℃, above 247℃, above 248℃, above 249℃, above 250℃, above 251℃, above 252℃, above 253℃, above 254℃, above 255℃, above 256℃, above 257℃ It may be 258°C or higher or 259°C or higher, and the temperature of the cylinder head is 260°C or lower, 259°C or lower, 258°C or lower, 257°C or lower, 256°C or lower, 255°C or lower, 254°C or lower, and 253°C. It can be 252℃ or lower, 251℃ or lower, 250℃ or lower, 249℃ or lower, 248℃ or lower, 247℃ or lower, 246℃ or lower, 245℃ or lower, 244℃ or lower, 243℃ or lower, 242℃ or lower, or 241℃ or lower. there is. Preferably, the temperature of the cylinder head may be 250°C.

In one embodiment, the temperature of the T-Dice may be 220 to 240°C, and more specifically, the temperature of the T-Dice may be 220°C or higher, 221°C or higher, 222°C or higher, 223°C or higher, or 224°C or higher. , above 225℃, above 226℃, above 227℃, above 228℃, above 229℃, above 230℃, above 231℃, above 232℃, above 233℃, above 234℃, above 235℃, above 236℃, 237 It may be ℃ or higher, 238 ℃ or higher, or 239 ℃ or higher, and the temperature of the T-dice is 240 ℃ or lower, 239 ℃ or lower, 238 ℃ or lower, 237 ℃ or lower, 236 ℃ or lower, 235 ℃ or lower, 234 ℃ or lower, 233℃ or lower, 232℃ or lower, 231℃ or lower, 230℃ or lower, 229℃ or lower, 228℃ or lower, 227℃ or lower, 226℃ or lower, 225℃ or lower, 224℃ or lower, 223℃ or lower, 222℃ or lower, or 221℃ It may be below. Preferably, the temperature of the T-dice may be 230°C.

In one embodiment, the temperature of the secondary cylinder is higher than the temperature of the primary cylinder, the temperature of the third to sixth cylinders is higher than the temperature of the secondary cylinder, and the temperature of the cylinder head is higher than the temperature of the third to sixth cylinders. The temperature of the 6th cylinder may be higher than that of the cylinder head, and the temperature of the T-dice may be lower than the temperature of the cylinder head.

In one embodiment, the temperature of the primary cylinder to which the raw materials mixed in the raw material mixing step are supplied is 200°C, and the temperature of the secondary cylinder to which the raw materials that have passed through the primary cylinder are supplied is 220°C. The temperature of the 3rd to 6th cylinders to which the raw materials passing through are supplied is 230°C, the temperature of the cylinder head located at the end of the cylinder to which the raw materials passing through the 6th cylinder are supplied is 250°C, and the raw materials passing through the cylinder head are 250°C. The temperature of the T-dice supplied may be 230°C.

In one embodiment, the cylinders consisting of the first cylinder, the second cylinder, and the third to sixth cylinders may be preheated to 250 to 260°C. More specifically, the cylinder is preheated to a temperature of 250 ℃ or higher, 251 ℃ or higher, 252 ℃ or higher, 253 ℃ or higher, 254 ℃ or higher, 255 ℃ or higher, 256 ℃ or higher, 257 ℃ or higher, 258 ℃ or higher or 259 ℃ or higher. In addition, the cylinder may be operated at a temperature of 260°C or less, 259°C or less, 258°C or less, 257°C or less, 256°C or less, 255°C or less, 254°C or less, 253°C or less, 252°C or less, or 251°C or less. It may have been preheated.

In one embodiment, the preheating may be performed for 2 to 4 hours.

As shown in FIG. 1B, in one embodiment, before the forming step, the step of applying a silicone release agent to one surface of the pressed sheet may be further included.

In one embodiment, in the cold pressing step, the upper and central rollers of the three primary cooling rollers may be at a temperature of 20 to 40°C. Specifically, the upper and central rollers are 20℃ or higher, 21℃ or higher, 22℃ or higher, 23℃ or higher, 24℃ or higher, 25℃ or higher, 26℃ or higher, 27℃ or higher, 28℃ or higher, 29℃ or higher, 30 It may be ℃ or higher, 31℃ or higher, 32℃ or higher, 33℃ or higher, 34℃ or higher, 35℃ or higher, 36℃ or higher, 37℃ or higher, 38℃ or higher, or 39℃ or higher, and the upper and central rollers may have a temperature of 40℃ or higher. ℃ or lower, 39℃ or lower, 38℃ or lower, 37℃ or lower, 36℃ or lower, 35℃ or lower, 34℃ or lower, 33℃ or lower, 32℃ or lower, 31℃ or lower, 30℃ or lower, 29℃ or lower, 28℃ or lower , it may be 27°C or lower, 26°C or lower, 25°C or lower, 24°C or lower, 23°C or lower, 22°C or lower, or 21°C or lower. Preferably, the upper and central rollers of the three primary cooling rollers may be at 30°C.

In one embodiment, in the cold pressing step, the lower rollers of the three primary cooling rollers may be at a temperature of 30 to 50°C. Specifically, the lower roller is 30 ℃ or higher, 31 ℃ or higher, 32 ℃ or higher, 33 ℃ or higher, 34 ℃ or higher, 35 ℃ or higher, 36 ℃ or higher, 37 ℃ or higher, 38 ℃ or higher, 39 ℃ or higher, 40 ℃ or higher , 41°C or higher, 42°C or higher, 43°C or higher, 44°C or higher, 45°C or higher, 46°C or higher, 47°C or higher, 48°C or higher, or 49°C or higher, and the lower roller is 50°C or lower, 49°C or higher. ℃ or lower, 48℃ or lower, 47℃ or lower, 46℃ or lower, 45℃ or lower, 44℃ or lower, 43℃ or lower, 42℃ or lower, 41℃ or lower, 40℃ or lower, 39℃ or lower, 38℃ or lower, 37℃ or lower , it may be 36°C or lower, 35°C or lower, 34°C or lower, 33°C or lower, 32°C or lower, or 31°C or lower. Preferably, the lower rollers of the three primary cooling rollers may be at 40°C.

In one embodiment, the temperature of the lower roller may be higher than the temperature of the upper and central rollers.

In one embodiment, in the cold pressing step, the two secondary cooling rollers may be at a temperature of 10 to 30°C. Specifically, the secondary cooling roller is 10 ℃ or higher, 11 ℃ or higher, 12 ℃ or higher, 13 ℃ or higher, 14 ℃ or higher, 15 ℃ or higher, 16 ℃ or higher, 17 ℃ or higher, 18 ℃ or higher, 19 ℃ or higher, 20 It may be ℃ or higher, 21℃ or higher, 22℃ or higher, 23℃ or higher, 24℃ or higher, 25℃ or higher, 26℃ or higher, 27℃ or higher, 28℃ or higher, or 29℃ or higher, and the secondary cooling roller may have a temperature of 30℃ or higher. ℃ or lower, 29℃ or lower, 28℃ or lower, 27℃ or lower, 26℃ or lower, 25℃ or lower, 24℃ or lower, 23℃ or lower, 22℃ or lower, 21℃ or lower, 20℃ or lower, 19℃ or lower, 18℃ or lower , it may be 17°C or lower, 16°C or lower, 15°C or lower, 14°C or lower, 13°C or lower, 12°C or lower, or 11°C or lower. Preferably, the two secondary cooling rollers may be at 20°C.

In one embodiment, the temperature of the secondary cooling roller may be lower than that of the primary cooling roller.

In another aspect, the present invention may relate to a system for manufacturing sheets for containers made of polypropylene. Specifically, from another aspect, the present invention may relate to a system for manufacturing a polypropylene container sheet by the above method.

Figure 2 shows the configuration of a manufacturing system for a polypropylene container sheet according to an embodiment.

As shown in FIG. 2, in one embodiment, the system may include a raw material mixing section, an extrusion section, a pressing section, a release agent application section, a forming section, and a winding section.

Specifically, in one embodiment, the system:

A raw material mixing section for mixing homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer at a weight ratio of 20 to 40:20 to 40:30 to 50; The raw materials mixed in the raw material mixing section are mixed into a cylinder consisting of a primary cylinder at 190 to 210°C, a secondary cylinder at 210 to 230°C, and a 3rd to 6th cylinder at 220 to 240°C, a cylinder head at 240 to 260°C, and An extrusion unit that melts and extrudes by passing it through a T-die at 220 to 240°C; A pressing unit that compresses the raw material extruded from the extrusion unit into a sheet by passing the raw material through three primary cooling rollers arranged in the longitudinal direction and two secondary cooling rollers arranged in the longitudinal direction; a release agent application unit that applies a silicone release agent to one surface of the sheet pressed in the compression unit; a molding unit that cuts both ends of the sheet to a predetermined size while moving the sheet coated with the release agent through a plurality of horizontal rollers arranged in the transverse direction; And it may include a winding unit that winds the sheet cut from the forming unit onto a winder.

The raw materials and weight ratio in the raw material mixing section, the temperature of the cylinder, cylinder head, and T-dice in the extrusion section, and the temperature of the cooling roller in the pressing section are the same as described above, so the following description is omitted.

Figure 3 schematically shows the configuration of the pressing portion of the manufacturing system for polypropylene container sheets according to one embodiment.

As shown in Figure 3, the raw material supplied from the extrusion unit can be cooled and compressed into a sheet while sequentially passing through three primary cooling rollers and two cooling rollers arranged in the longitudinal direction.

Figure 4 schematically shows the configuration of the release agent application portion of the manufacturing system for polypropylene container sheets according to one embodiment.

As shown in Figure 4, the sheet supplied from the compression unit passes between two rollers arranged in the longitudinal direction, and at this time, a silicone release agent is supplied to the roller located at the bottom to apply silicone to one side of the sheet passing between the two rollers. A mold release agent may be applied.

In one embodiment, the silicone mold release agent may be a food grade silicone mold release agent.

In one embodiment, pieces from both ends of the sheet cut from the molding unit may be added to the raw material mixing unit and mixed with the homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer.

In one embodiment, in the raw material mixing section, the homopolypropylene, polypropylene-ethylene copolymer, polyethylene-α-olefin copolymer, and both end pieces of the cut sheet are 10 to 30:10 to 30:10 to 30. : Can be mixed at a weight ratio of 30 to 50.

Hereinafter, the configuration of the present invention and its effects will be described in more detail through specific examples. However, these examples are for illustrating the present invention in more detail, and the scope of the present invention is not limited to these examples.

[Example] Manufacturing of sheets for polypropylene containers

A polypropylene container sheet according to an embodiment of the present invention was manufactured through the following process.

First raw material mixing process

Homopolypropylene (HIPRENE H710, GS Caltex Co., Ltd.), polypropylene-ethylene copolymer (HIPRENE M710, GS Caltex Co., Ltd.), and polyethylene-α-olefin copolymer (HDPE-5502, Daelim Industrial Co., Ltd.) at 30:30:40 ratio. The raw materials were mixed by weight ratio.

Melt extrusion process

Preheat the cylinder to 250℃ for 3 hours and pass it through a primary cylinder at 200℃, a secondary cylinder at 220℃, 3rd to 6th cylinders at 230℃, a cylinder head at 250℃, and a T-die at 230℃. It was melted and extruded to a uniform thickness of 0.2 to 2 mm.

Cold pressing process

The raw material extruded from the T-die to a uniform thickness was passed through three cooling rollers at 30°C, 30°C, and 40°C from the top, respectively, and then passed through two cooling rollers at 20°C from the top and bottom, respectively, to be compressed into a sheet form.

Release agent application process

While passing the pressed sheet between two rollers, a food-grade silicone mold release agent (SNOGEN BR-350) was applied to the lower surface.

molding process

The sheet coated with the silicone release agent was moved through a plurality of horizontal rollers, and both ends of the sheet were cut to have a width of 1400 mm.

Second raw material mixing process

Homopolypropylene (HIPRENE H710, GS Caltex Co., Ltd.), polypropylene-ethylene copolymer (HIPRENE M710, GS Caltex Co., Ltd.), polyethylene-α-olefin copolymer (HDPE-5502, Daelim Industrial Co., Ltd.), and sheets cut in the above molding process. The raw materials were mixed by mixing both ends at a weight ratio of 20:20:20:40.

In the same manner as above, a melt extrusion process, a cold pressing process, a release agent application process, and a molding process were performed, followed by a winding process in which the sheet was wound around a winder, and finally, a sheet for a polypropylene container was manufactured.

Claims (5)

A method for manufacturing a polypropylene container sheet, comprising:
A raw material mixing step of mixing homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer at a weight ratio of 20 to 40:20 to 40:30 to 50;
The mixed raw materials are mixed into a cylinder consisting of a primary cylinder at 190 to 210°C, a secondary cylinder at 210 to 230°C, and a 3rd to 6th cylinder at 220 to 240°C, a cylinder head at 240 to 260°C, and a cylinder at 220 to 240°C. A melt extrusion step of melting and extruding by passing through a T-die;
A cold pressing step of compressing the extruded raw material into a sheet by passing it through three primary cooling rollers arranged in the longitudinal direction and two secondary cooling rollers arranged in the longitudinal direction;
A forming step of cutting both ends of the sheet according to a predetermined size while moving the pressed sheet through a plurality of horizontal rollers arranged in the transverse direction; and
It includes a winding step of winding the cut sheet on a winder,
The temperature of the secondary cylinder is higher than the temperature of the primary cylinder, the temperature of the 3rd to 6th cylinders is higher than the temperature of the secondary cylinder, and the temperature of the cylinder head is higher than that of the 3rd to 6th cylinders. higher than the temperature, and the temperature of the T-dice is lower than the temperature of the cylinder head,
The upper and central rollers of the three primary cooling rollers are at a temperature of 20 to 40° C. and the lower rollers are at a temperature of 30 to 50° C., the temperature of the lower roller is higher than that of the upper and central rollers, and the temperature of the two secondary cooling rollers is higher than that of the upper and central rollers. is 10 to 30°C, and the temperature of the secondary cooling roller is lower than that of the primary cooling roller,
The first cylinder, second cylinder, and third to sixth cylinders are preheated to 250 to 260°C,
In the raw material mixing step,
Mixing both end pieces of the sheet cut in the forming step with the homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer,
wherein the homopolypropylene, polypropylene-ethylene copolymer, polyethylene-α-olefin copolymer and both end pieces of the cut sheet are mixed in a weight ratio of 20:20:20:40. delete The method of claim 1, wherein before the forming step,
Characterized in that it further comprises the step of applying a silicone release agent to one surface of the pressed sheet. A system for producing sheets for containers made of polypropylene by the method according to claim 1 or 3, comprising:
A raw material mixing section for mixing homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer at a weight ratio of 20 to 40:20 to 40:30 to 50;
The raw materials mixed in the raw material mixing section are mixed into a cylinder consisting of a primary cylinder at 190 to 210°C, a secondary cylinder at 210 to 230°C, and a 3rd to 6th cylinder at 220 to 240°C, a cylinder head at 240 to 260°C, and An extrusion unit that melts and extrudes by passing it through a T-die at 220 to 240°C;
A pressing unit that compresses the raw material extruded from the extrusion unit into a sheet by passing the raw material through three primary cooling rollers arranged in the longitudinal direction and two secondary cooling rollers arranged in the longitudinal direction;
a release agent application unit that applies a silicone release agent to one surface of the sheet pressed in the compression unit;
a molding unit that cuts both ends of the sheet to a predetermined size while moving the sheet coated with the release agent through a plurality of horizontal rollers arranged in the transverse direction; and
It includes a winding unit that winds the sheet cut from the forming unit onto a winder,
The temperature of the secondary cylinder is higher than the temperature of the primary cylinder, the temperature of the 3rd to 6th cylinders is higher than the temperature of the secondary cylinder, and the temperature of the cylinder head is higher than that of the 3rd to 6th cylinders. higher than the temperature, and the temperature of the T-dice is lower than the temperature of the cylinder head,
The upper and central rollers of the three primary cooling rollers are at a temperature of 20 to 40° C. and the lower rollers are at a temperature of 30 to 50° C., the temperature of the lower roller is higher than that of the upper and central rollers, and the temperature of the two secondary cooling rollers is higher than that of the upper and central rollers. is 10 to 30°C, and the temperature of the secondary cooling roller is lower than that of the primary cooling roller,
The first cylinder, second cylinder, and third to sixth cylinders are preheated to 250 to 260°C,
The raw material mixing section,
Mixing both end pieces of the sheet cut from the molding section with the homopolypropylene, polypropylene-ethylene copolymer, and polyethylene-α-olefin copolymer,
The system of claim 1, wherein the homopolypropylene, polypropylene-ethylene copolymer, polyethylene-α-olefin copolymer and both end pieces of the cut sheet are mixed in a weight ratio of 20:20:20:40. delete