KR20220041326A - protective materials for steel coil wire - Google Patents

Abstract

Disclosed is a corner protective packaging material for steel, capable of preventing product quality deterioration caused by damage to a packaging material by improving resistance characteristics to an external force such as an external impact while minimizing an increase in a thickness of a base sheet. The corner protective packaging material for steel can protect a corner of an outer diameter or an inner diameter of a steel coil. To this end, provided is the corner protective packaging material for steel, in which a base sheet and a reinforcement layer are stacked and formed with an adhesive layer therebetween. Moreover, in the reinforcement layer, tear does not occur on a surface of a material in a scratch test by KS M ISO 19252 test method, wherein the test conditions are as follows: 2 N of load, 5 mm/sec of a scratch speed, 100 mm of a scratch distance, and Φ 1.0 mm stainless steel of a chip.

Description

Protective materials for steel coil wire

The present invention relates to a corner protection packaging material for steel, and more particularly, to a corner protection packaging material for steel that can prevent damage to the packaging material itself from sharp steel coil edges.

Until steel coils such as cold-rolled coils are produced at the steel mill and delivered to consumers, the coils are loaded in a certain place before transporting them, and the coils are subjected to impact several times during the logistics process, such as loading and unloading them by means of transport. will lose Such an impact damages the surface of the steel sheet. In particular, the cold-rolled steel sheet used to produce automobile steel sheets or home appliances causes fatal defects in product quality when the surface is damaged.

Therefore, when steel products such as cold-rolled coils are usually produced, the steel coils are packaged with a packaging material before transport and transport to protect the steel products from external impact. Conventional main packaging materials include rust-proof paper, waterproof paper, vinyl, cardboard (general cardboard, waterproof cardboard, corner cardboard), corrugated cardboard, hard board (MDF), steel (inner/outer protection plate, inner/outer ring, end-side plate), plastic (side plate), band, fastener (seal), seal pad (seal pad), adhesive tape, etc., these are applied in multiple layers to protect the steel coil. By applying such a packaging material, damage to the product is prevented from external impact, and corrosion or rust that may occur due to the adhesion of moisture or other impurities to steel products is prevented.

On the other hand, the corners of the inner and outer diameters of the coil are relatively easily damaged by external impact due to their sharpness, so thick cardboard was applied to the corners of the steel coil. In other words, it was intended to prevent damage to the rust preventive paper by packaging the steel coil using rust preventive paper containing a vaporizable rust preventive agent and applying the corner cardboard on it, or applying the corner cardboard to the corner part of the steel coil and wrapping it with the rust preventive paper on it. .

Cardboard is a fibrous material made of several layers of paper, which is suitable for alleviating damage caused by external forces such as pressure and impact at the edge of heavy steel coils, but accumulates external forces such as long-term use or frequent external shocks The cardboard, which is the protective layer, is damaged, and eventually, it is impossible to prevent rust from occurring in the steel coil due to the inflow of moisture and the expression of rust-generating factors contained in the paper.

Plastic products are also used as edge protection packaging materials instead of paper materials. However, plastic products are weak at low temperature and break when a strong force is applied during banding, transport, or transportation during the packaging process. This increases the workload compared to the angle-type product, and there is a problem in economic efficiency due to the increase in material cost.

Korea Patent No. 1010514 discloses a corner cardboard made by bonding 2 to 5 base sheets coated with polyethylene resin on both sides, but it is difficult to prevent damage to the cardboard due to external force caused by a heavy object only by coating the polyethylene resin, When multiple layers of the base sheet are adhered, of course, resistance to external impact can be improved, but there are problems in workability deterioration and material cost increase due to an increase in thickness.

Korean Patent Registration No. 1359899 discloses a protective material for the corners of a steel coil formed by attaching an anti-rust film to one surface of a base sheet, a rust-preventing paper to the other surface, and further attaching a liner paper between the base sheet and the anti-corrosive paper, but paperboard, etc. There is a limit to improving the resistance performance against external force by attaching the anti-rust film and anti-rust paper to the base sheet of the and rising material cost.

The present invention provides a corner protection packaging material for steel, which can prevent product quality deterioration due to damage to the packaging material by improving resistance characteristics against external forces such as external impact while minimizing the increase in the thickness of the base sheet in the edge protection packaging material for steel want to

In order to solve the above problems, the present invention provides a corner protection packaging material for steel for protecting a corner portion of an outer diameter or an inner diameter of a steel coil, a base sheet and a reinforcing material layer are laminated with an adhesive layer therebetween, and the reinforcing material layer is KS M Provides edge protection packaging for steel that does not tear on the material surface in a scratch test according to the ISO 19252 test method (test conditions: load 2 N, scratch speed 5 mm/sec, scratch distance 100 mm, chip φ 1.0 mm stainless steel) do.

In addition, the base sheet provides a cardboard, liner paper, corrugated paper, kraft paper or a composite thereof, and provides an edge protection packaging material for steel, characterized in that the thickness is 0.5 to 8 mm.

In addition, the base sheet provides an edge protection packaging material for steel, characterized in that it contains a vaporizable rust preventive.

In addition, the reinforcing material layer provides a corner protective packaging material for steel, characterized in that the hemp, non-woven fabric, mesh, plastic sheet, or a composite thereof.

In addition, the sack is polyethylene, polypropylene, polyester, or a composite material thereof, and provides an edge protection packaging material for steel, characterized in that the number of carpenters is 5 to 16 trees and the thickness is 500 to 2,000 denier.

In addition, the nonwoven fabric is polyethylene, polypropylene, polyester or a composite material thereof, and provides a corner protection packaging material for steel, characterized in that the basis weight is 20 to 500 g / m 2 .

In addition, the mesh is polyethylene, polypropylene, polyester, rayon, nylon, or a composite material thereof, and provides an edge protection packaging material for steel, characterized in that the mesh size is 10 to 500 mesh.

In addition, the plastic sheet is polyethylene, polypropylene, ethylene vinyl acetate, polyester, polyvinyl chloride, or a composite material thereof, and provides an edge protection packaging material for steel, characterized in that the thickness is 0.05 to 1.0 mm.

In addition, the adhesive layer provides a corner protective packaging material for steel, characterized in that it comprises a polyolefin-based resin or a modified polyolefin-based resin.

In addition, it provides a corner protective packaging material for steel, characterized in that the paper layer is further formed between the base sheet and the reinforcing material layer.

According to the present invention, in the edge protection packaging material for steel, by laminating a reinforcing material layer having excellent scratch resistance above a certain level on the base sheet, the resistance to external force such as external impact is dramatically improved while minimizing the increase in the thickness of the packaging material. It is possible to completely prevent deterioration of quality such as rust of the product due to damage to the packaging material.

In addition, the specification for realizing the target physical properties of scratch resistance in specific materials such as hemp, non-woven fabric, mesh, and plastic sheet, which can give the required resistance to external forces such as external impact, is clearly presented to enable easy selection of packaging materials. do.

1 is a schematic view showing a cross-section of a corner protection packaging material for steel according to the present invention;
Figure 2 is a schematic view showing a cross section of the edge protection packaging material for steel according to an embodiment of the present invention;
3 is a photograph showing the results of the rust prevention evaluation in the test example of the present invention;
4 is a schematic diagram illustrating a method for evaluating scratch properties in a test example of the present invention.

Hereinafter, the present invention will be described in detail through preferred embodiments. Prior to this, the terms or words used in the present specification and claims should not be construed as being limited to conventional or dictionary meanings, and the inventor should properly understand the concept of the term in order to best describe his invention. Based on the principle that can be defined, it should be interpreted as meaning and concept consistent with the technical idea of the present invention. Accordingly, since the configuration of the embodiments described in the present specification is only the most preferred embodiment of the present invention and does not represent all the technical spirit of the present invention, various equivalents and modifications that can be substituted for them at the time of the present application It should be understood that there may be Also, throughout the specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated.

The present inventors have used cardboard as a material suitable for mitigating damage to external forces such as pressure and shock in the prior art in the edge protection packaging material for steel, but when using for a long time or when external shocks are frequent, the protective layer is When the paperboard is damaged, and when the base sheet is applied thickly, such as using multiple layers of paperboard, to solve this problem, the workability is significantly reduced. However, by applying a reinforcing material layer having excellent scratch resistance properties, it was found that the resistance to external forces such as pressure and external impact applied to the packaging material in contact with a heavy object was dramatically improved, leading to the present invention.

1 is a schematic view showing a cross-section of the edge protection packaging material for steel according to the present invention.

Referring to FIG. 1, in the present invention, in the edge protection packaging material 100 for steel for protecting the edge portion of the outer diameter or inner diameter of the steel coil, the base sheet 110 and the reinforcing material layer 120 are the adhesive layer 130. The reinforcing material layer 120 is laminated in between, and the material in a scratch test by the KS M ISO 19252 test method (test conditions: load 2 N, scratch speed 5 mm/sec, scratch distance 100 mm, chip φ 1.0 mm stainless steel) Disclosed is a corner protection packaging material 100 for steel that does not tear on the surface.

In the present invention, the reinforcing material layer 120 may be formed on one or both sides of the base sheet 110, and hereinafter, the case in which the reinforcing material layer 120 is formed on one surface of the base sheet 110 will be mainly described. .

In the present invention, the base material sheet 110 is a base material for protecting the edges of steel products, and conventional cardboard can be used. Therefore, recycled paper has been used as edge cardboard from the past. It can be preferably used also in the present invention. As the base sheet 110, cardboard, liner paper, corrugated paper, kraft paper, or a composite thereof may be used.

In the present invention, the thickness of the base sheet 110 may be 0.5 to 8 mm. That is, in the prior art, the base sheet 110 was applied thickly, such as in multiple layers, to prevent damage to the packaging material, but in this case, there is a problem in that workability is significantly reduced. In this regard, the thickness of the base sheet 110 may be preferably 0.5 to 5 mm, and more preferably 1 to 3 mm.

The base sheet 110 contains a vaporizable rust preventive agent and is vaporized during product packaging, thereby forming a thin passivation film on the metal surface of the product to realize vaporization rust prevention performance.

Although it is not particularly limited as such a vaporization rust preventive component, it is necessary to have a composition suitable for balancing vaporization and sustained release properties and for impregnating or coating a substrate, particularly a paper substrate such as a cardboard, and thus, in the present invention, the rust preventive agent is a vaporization rust preventive agent, for example, a fatty acid. or a salt thereof; A cyclic compound containing oxygen, nitrogen or sulfur, an alkali metal salt; and an aromatic acid or a salt thereof; may include at least one selected from the group consisting of.

The fatty acid may be selected from fatty acids having 3 to 20 carbon atoms, preferably butyric acid, caproic acid, caprylic acid, capric acid, la Uric acid (lauric acid), stearic acid (stearic acid), etc. may be selected and used.

In addition, as the cyclic compound, for example, 1,2,3-benzotriazole, tolytriazole, 5-chlorobenzotriazole, mergtobenzotriazole, 3-aminotriazole, imidazole, benzoimidazole, etc. can be selected and used.

In addition, as the alkali metal salt, for example, sodium carbonate, sodium benzoate, sodium nitrite, potassium nitrite, potassium nitrite, etc. may be selected and used.

In addition, as the aromatic acid, for example, salicylic acid, benzoic acid, etc. may be selected and used.

A suitable content ratio of the vaporizable rust inhibitor is 5 to 30% by weight of the fatty acid or its salt, 1 to 30% by weight of the triazole, 1 to 20% by weight of the alkali metal salt, and 5 to 40% by weight of the aromatic acid or its salt; The remaining components may be composed of water, alcohol, or a mixture thereof.

The base sheet 110 containing the rust preventive agent may be manufactured by, for example, impregnating or coating the base sheet 110 with a vaporizable rust preventive agent in a manner such as gravure, spraying, or knife, and then drying with hot air or a heating roll. At this time, the application amount of the vaporization rust preventive agent may be different depending on the required vaporization degree, but may be appropriately determined, for example, in the range of 5 to 100 g/m 2 .

In the present invention, the reinforcing material layer 120 is adhered to the base sheet 110 and is a layer for improving resistance properties against external forces such as pressure and external impact applied to the base sheet 110 in contact with a heavy object, and scratch resistance. By adopting a material having specific physical properties with respect to the rigidity of the property, the resistance to external force is dramatically improved without increasing the thickness of the base sheet 110 . Although it is difficult to clearly understand the reason why the rigidity of the reinforcing material layer 120 prevents damage to the base sheet 110, when a load or impact caused by a sharp heavy object is applied, In the case of the base sheet 110, the stress to withstand such an external force is good, but there is a limit when the external force is accumulated. It is understood that this is because the critical limit at which the base sheet 110 is damaged is greatly increased by bringing the deformation behavior of the base sheet closer to the reinforcing material layer 120 .

At this time, as the reinforcing material layer 120 , it may be considered to apply a film layer such as polyethylene, which is employed to prevent moisture penetration in the prior art to which the present invention belongs, but due to the property that the film is easily damaged, the realization of the required physical properties is difficult. impossible.

As the material for the reinforcing material layer 120, for example, hemp, non-woven fabric, mesh, plastic sheet, or a composite thereof may be employed, and preferably, hemp, non-woven fabric or plastic sheet may be employed.

When the hemp is used as the material for the reinforcing material layer 120, in terms of realizing the required physical properties, as polyethylene, polypropylene, polyester, or a composite material thereof, the number of carpenters (the number of threads used per inch) is 5 to 16 items. and a thickness of 500 to 2,000 denier, preferably 6 to 14 necks of carpenter and 600 to 1,500 denier in thickness, more preferably 7 to 12 necks of carpenter and 700 to 1,200 denier in thickness may be used.

In addition, when the nonwoven fabric is used as the material for the reinforcing material layer 120, in terms of realizing the required physical properties, as a polyethylene, polypropylene, polyester or a composite material thereof, the basis weight is 20 to 500 g/m 2 , preferably 30 to 300 g/m 2 , more preferably 40 to 200 g/m 2 may be used.

In addition, when the mesh is used as the material for the reinforcing material layer 120, in terms of realizing the required physical properties, as a polyethylene, polypropylene, polyester, rayon, nylon, or a composite material thereof, the mesh size is 10 to 500 mesh, preferably 15 to 300 mesh, more preferably a mesh size of 20 to 100 mesh may be used.

In addition, when the plastic sheet is used as the material for the reinforcing material layer 120, in terms of realizing the required physical properties, it is a polyethylene, polypropylene, ethylene vinyl acetate, polyester, polyvinyl chloride or a composite material thereof, and has a thickness of 0.05 to 1.0. mm, preferably 0.08 to 0.5 mm, more preferably 0.1 to 0.3 mm can be used.

In the present invention, the adhesive layer 130 is a layer for adhering the base sheet 110 and the reinforcing material layer 120 , and may occur from the base material while the base sheet 110 approaches the deformation behavior of the reinforcing material layer 120 . Polyolefin-based resins such as polyethylene-based, polypropylene-based, and ethylene vinyl acetate, or polyolefin-based resins modified with these resins may be preferably used to prevent rust and corrosion.

The adhesive layer 130 may be laminated in the form of a coating layer between the base sheet 110 and the reinforcing material layer 120, wherein the coating layer is i) a resin between the base sheet 110 and the reinforcing material layer 120 T-die Alternatively, it is formed by extrusion and thermal bonding in a spraying method, or ii) extruding the resin in a T-die method to form a sheet, and then laminating the sheet between the base sheet 110 and the reinforcing material layer 120 to be formed. there is.

Figure 2 is a schematic view showing a cross section of the edge protection packaging material for steel according to an embodiment of the present invention.

On the other hand, the edge protection packaging material 100 for steel according to the present invention is subjected to an angle processing step of forming an angle of approximately 90° using a roll processing machine or the like for application to a steel coil, etc. At this time, the base sheet 110 and the reinforcing material Depending on the difference in the material of the layer 120, it may be difficult to maintain the angle forming state (the state maintaining the angle), and in this case, workability may be deteriorated when packing in a steel coil or the like.

Therefore, according to one embodiment of the present invention, as shown in FIG. 2 , by further forming a paper layer 140 between the base sheet 110 and the reinforcing material layer 120 , the base sheet 110 and the reinforcing material layer 120 . ), it can compensate for the persistence of the angle formation state, which may be deteriorated due to the difference in material.

The paper layer 140 is not particularly limited as long as it is a type capable of supplementing the continuity of the angle forming state, and for example, kraft paper having a basis weight of 50 to 150 g/m 2 may be preferably used.

When the paper layer 140 is further laminated, the reinforcing material layer 120 and the paper layer 140 are adhesively coated in the above-described manner, or a laminate of the reinforcing material layer/adhesive coating layer/paper layer is manufactured using a general adhesive. After that, the packaging material 100 may be manufactured by adhering the base sheet 110 on the paper layer 140 of the laminate. In this case, the laminate may be formed on one surface of the base sheet 110 , but may be formed on both sides of the base sheet 110 , of course.

Hereinafter, the present invention will be described in more detail with reference to specific examples.

Example 1

Prepare kraft paper (100 g/m2) as the paper layer, prepare polyethylene sacks (10 × 10 necks, 1,000 denier) as the reinforcing material layer, and use the polyethylene resin as the adhesive coating layer (thickness 30 μm) in the T-die method. After extruding at an extrusion temperature of 300°C to prepare a laminate of reinforcing material layer/adhesive coating layer/paper layer, a 1 mm thick cardboard (650 g/m2) was made using a polyethylene-based adhesive on the paper layer of the laminate. A corner protective packaging material for steel was prepared by bonding the base sheet.

Example 2

A corner protective packaging material for steel was prepared in the same manner as in Example 1, except that a polypropylene nonwoven fabric (100 g/m 2 ) was used as the reinforcing material layer in Example 1.

Example 3

A corner protective packaging material for steel was prepared in the same manner as in Example 1, except that a polyethylene sheet (thickness 0.2 mm) was used as the reinforcing material layer in Example 1.

Example 4

As a paper layer in Example 1, vaporizable rust inhibitor (caprylate 20-25 wt%, 1,2,3-benzotriazole 5-10 wt%, sodium nitrite 2-5 wt%, benzoate 20-25 wt% and 45-50 wt% of water) 20 g/m 2 by gravure method, hot-air drying, and a rust preventive-containing paper was used to prepare a corner protective packaging material for steel in the same manner as in Example 1 .

Comparative Example 1

White kraft paper using natural pulp was coated with polyethylene resin (LDPE, thickness 30 μm), and the coated surface was turned to the outside and laminated three times in the same manner to prepare a corner protective packaging material for steel with a total thickness of 1.5 mm.

Comparative Example 2

A corner protective packaging material for steel was prepared in the same manner as in Comparative Example 1, except that kraft paper using recycled pulp was used instead of the coated white kraft paper in Comparative Example 1.

test example

For the packaging materials prepared according to the Examples and Comparative Examples, scratch properties and rust prevention properties were evaluated by the following method, and the results are shown in Table 1 and FIG. 3 below.

[Evaluation of scratch properties]

As shown in Fig. 4, KS M ISO 19252 test method was applied with the reinforcement layer (coating layer in the case of the comparative example) as the upper surface (test conditions: load 2 N, scratch speed 5 mm/sec, scratch distance 100 mm, chip φ 1.0 mm stainless steel) to conduct a scratch test, and visually observe the surface of the material with reference to the preceding literature (Jil Won Won, “Quantitative analysis of scratch characteristics and application of polymer materials”, Polymer Science and Technology Vol. 20 No. 3, June 2009) The types of scratches were expressed as “irritation”, “wedge” and “tear”.

In the above test method, the scratch property is a ploughing phenomenon having a shallow depth and a small width that occurs along the indenter as the indenter slides on the surface of the polymer material, and a wedge phenomenon that causes damage to the uneven pattern on the surface of the material , and it appears as a cutting phenomenon that causes tearing on the surface of the material. The ridge phenomenon means that there is no major damage other than the pressing effect by the indenter because an external force is applied to the surface of the material as the indenter slides. The wedge phenomenon is caused by an increase in the frictional force between the material and the indenter due to the increase in the external force applied by the indenter. As it acts, the indenter makes a slight vibration on the surface of the material by different forces, and this vibration causes a wedge-shaped surface damage on the surface of the material. The cutting phenomenon occurs when more than a specific load is applied to the surface of the material, and fragments are generated along with irregular tearing on the surface of the polymer material. That is, it creates a deep scratch depth on the material surface.

[Evaluation of rust prevention]

In accordance with the KS T 1086 test method, 8 cycles of 5°C for 8 hours and 50°C for 16 hours in a thermo-hygrostat were applied as one cycle, and 8 cycles were applied.

Referring to Table 1, when the reinforcing material layer is formed on the base sheet with hemp, non-woven fabric or plastic sheet material according to the present invention, compared to the packaging material reinforced with the existing film layer (Comparative Examples 1 and 2), the increase in the thickness of the packaging material is minimized while minimizing the external force It can be seen that the resistance to the resistance is significantly improved. However, it was confirmed that the hemp material exhibited better resistance properties than the non-woven material as a reinforcing material layer at the same thickness.

On the other hand, referring to FIG. 3 , as a result of performing the rust prevention evaluation under somewhat harsh conditions, in the case of Comparative Examples 1 and 2, unlike the Example in which rust generation was not observed at all, some fine rust generation (circled in FIG. 3 ) appeared, and the rust prevention property It was also confirmed that the packaging material laminated structure according to the present invention exhibited superior characteristics compared to the existing packaging material structure.

Preferred embodiments of the present invention described above are disclosed to solve the technical problem, and various modifications, changes, additions, etc. will be possible within the spirit and scope of the present invention by those of ordinary skill in the art to which the present invention pertains. , such modifications and changes should be regarded as belonging to the following claims.

100: edge protection packaging material for steel 110: base sheet
120: reinforcing material layer 130: adhesive layer
140: paper layer

Claims (10)

In the steel edge protection packaging material for protecting the outer diameter or inner diameter edge of a steel coil, a base sheet and a reinforcing material layer are laminated with an adhesive layer in between, and the reinforcing material layer is KS M ISO 19252 test method (test condition: load 2 N, scratch speed 5 mm/sec, scratch distance 100 mm, chip φ 1.0 mm stainless steel edge protection packaging material for steel that does not tear on the surface of the material in a scratch test. According to claim 1,
The base sheet is cardboard, liner paper, corrugated paper, kraft paper or a composite thereof, and the edge protection packaging material for steel, characterized in that the thickness is 0.5 to 8 mm. According to claim 1,
The base sheet is an edge protection packaging material for steel, characterized in that it contains a vaporizing rust inhibitor. According to claim 1,
The reinforcing material layer is a corner protective packaging material for steel, characterized in that the hemp, non-woven fabric, mesh, plastic sheet, or a composite thereof. 5. The method of claim 4,
The hemp is polyethylene, polypropylene, polyester, or a composite material thereof, and the number of carpenters is 5 to 16, and the thickness is 500 to 2,000 denier. 5. The method of claim 4,
The nonwoven fabric is polyethylene, polypropylene, polyester, or a composite material thereof, and a corner protective packaging material for steel, characterized in that the basis weight is 20 to 500 g / m 2 . 5. The method of claim 4,
The mesh is polyethylene, polypropylene, polyester, rayon, nylon, or a composite material thereof, and the mesh size is 10 to 500 mesh. 5. The method of claim 4,
The plastic sheet is polyethylene, polypropylene, ethylene vinyl acetate, polyester, polyvinyl chloride or a composite material thereof, and the edge protection packaging material for steel, characterized in that the thickness of 0.05 to 1.0 mm. According to claim 1,
The adhesive layer is a corner protective packaging material for steel, characterized in that it comprises a polyolefin-based resin or a modified polyolefin-based resin. According to claim 1,
Edge protection packaging material for steel, characterized in that a paper layer is further formed between the base sheet and the reinforcing material layer.

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