KR101427886B1 - Super coated manila board and coating composition for paper board - Google Patents

Abstract

The present invention relates to a SC Manila board having high whiteness and opacity and having excellent printability and a coating composition for a board which can give excellent printability while imparting high whiteness and opacity.

Description

SC MANILA COATING COMPOSITION FOR CARDBOARD AND CARBON COMPOSITION FOR PAPER BOARD BACKGROUND OF THE INVENTION 1. Field of the Invention < RTI ID = 0.0 >

The present invention relates to an SC Manila board having high whiteness and opacity and having excellent printability and a coating composition for a board which can give excellent printability while imparting high whiteness and opacity.

SC The super coated manila board is a type of white board which is coated on the surface and coated with various waste paper such as waste newspapers and waste corrugated paper under the surface layer made of white ledger. It is a multi-layered cardboard product that is produced by multiple layered layers. It has excellent printability and is mainly used as an external packaging paper.

The SC Manila carton typically comprises a coating layer comprising heavy calcium carbonate, a surface layer comprising pulp from a white ledger, a core layer comprising pulp from waste corrugated paper, and a back layer comprising pulp from waste newspaper And a core layer, a surface layer, and a coating layer are sequentially laminated on the rear layer.

Such SC Manila carton uses pulp (hereinafter referred to as "pulp pulp") obtained from white paper waste paper, waste newspaper, and corrugated cardboard paper, so that manufacturing cost can be reduced compared with the case of using environmentally-friendly and costly chemical pulp.

However, the ground layer made of the pulp pulp has a low whiteness degree compared to the ground layer made of the non-phage pulp (e.g., chemical pulp) even if the ink is deinked. Particularly, the layer made of the pulp obtained from corrugated corrugated cardboard has a yellowish color or a whitish color and has the lowest whiteness compared to the layer made of other pulp pulp (for example, white pulp pulp, waste newspaper pulp). In addition, even when the pulp amount is controlled to be the same throughout the entire surface in manufacturing, the surface layer has a portion having a small amount of pulp (in this case, relatively high transparency) and a portion having a large amount of pulp (in this case, relatively low transparency) As the difference in whiteness between the surface layer and the core layer is larger, the surface of the core layer visible through the portion of the pulp of the surface layer becomes white stain, and the aesthetic effect may be degraded have.

Therefore, conventionally, in order to conceal the color or the foreign substance of the core layer, the thickness of the surface layer is increased or a layer (hereinafter referred to as a "sublayer") containing pulp obtained from the waste newspaper is sandwiched between the surface layer and the core layer. .

However, the supply and demand of the white paper used in the production of the SC manila carton is difficult at present, and the recovery rate of the pulp obtained from the white paper is lowered and the price of the white paper pulp is increasing. As a result, when the thickness of the surface layer is increased, the SC unit cost of the Manila sheet increases, which is not effective in the industry competition. On the other hand, even if a sublayer is interposed between the surface layer and the core layer, the surface of the sublayer is seen as a white spot due to the difference in whiteness between the surface layer and the sublayer.

It is an object of the present invention to provide a SC Manila paperboard having a low manufacturing cost, high whiteness and opacity, and excellent printability.

Another object of the present invention is to provide a coating composition for a paper which can improve the printability while increasing the whiteness and opacity of the paperboard economically.

The present invention relates to a top coating layer formed of a composition for top coating comprising heavy calcium carbonate and a binder; An undercoat layer formed from a composition for undercoating comprising heavy calcium carbonate, precipitated calcium carbonate and a binder, wherein the precipitated calcium carbonate has an average particle diameter of 1 to 5 mu m; A surface layer comprising white ledger pulp; A core layer comprising one selected from the group consisting of ground pulp, pulp pulp pulp and corrugated cardboard pulp; And a backside layer containing waste newspaper pulp, wherein the core layer, the surface layer, the undercoat layer, and the topcoat layer are sequentially laminated on the back layer.

The present invention also provides a coating composition for paper, comprising heavy calcium carbonate, precipitated calcium carbonate, latex and an additive, wherein the precipitated calcium carbonate has an average particle size of 1 to 5 탆.

The SC manila paperboard according to the present invention includes an undercoat layer formed of a composition for undercoating containing precipitated calcium carbonate having an average particle size of about 1 to 5 mu m to thereby improve economical whiteness and opacity and improve printability have.

Also, since the coating composition for paper according to the present invention contains precipitated calcium carbonate having an average particle size of about 1 to 5 탆, the whiteness and opacity of the paperboard can be economically improved, and printing suitability can be improved.

1 is a cross-sectional view of a SC Manila carton according to an example of the present invention.
2 is a cross-sectional view of a SC Manila carton according to another example of the present invention.

Hereinafter, the present invention will be described.

The present invention relates to a SC Manila paperboard, which is a type of whiteboard, and is characterized in that an undercoat layer is formed by using precipitated calcium carbonate having an average particle size of about 1 to 5 μm as one component of a composition for undercoating do. Since the color or spots of the core layer are concealed by the undercoat layer, the SC Manila carton of the present invention can improve the whiteness and opacity economically and improve printability.

The present invention uses precipitated calcium carbonate having an average particle size of about 1 to 5 mu m as one component of a composition for undercoating. The precipitated calcium carbonate scatters light, thereby increasing the opacity and whiteness of the SC Manila carton. In addition, the precipitated calcium carbonate changes the pore characteristics of the undercoat layer, thereby improving the printability of the SC Manila paperboard. In addition, in forming the undercoat layer, since the precipitated calcium carbonate does not lower the fluidity of the undercoating composition unlike the precipitated calcium carbonate having an average particle diameter of less than 1 mu m, workability can be improved. On the other hand, it is difficult to produce precipitated calcium carbonate having an average particle diameter exceeding 5 탆, and it is difficult to maintain the shape and particle size of the particles due to the breakage of particles at the time of use as a component of the coating composition, The fluidity of the composition is lowered, and the light scattering does not occur properly and the whiteness and opacity are not improved.

In addition, the undercoat layer formed using the composition for undercoating containing the precipitated calcium carbonate having an average particle size of about 1 to 5 占 퐉 as one component has high opacity and whiteness, and therefore has excellent hiding effect. Therefore, unlike the conventional SC Manila carton, the SC manila carton of the present invention does not need to increase the thickness of the surface layer in order to hide the color or spots of the core layer including the corrugated cardboard pulp, It is not necessary to interpose a sub-layer containing pulp obtained from waste newspaper. Thus, the SC Manila carton of the present invention may reduce the basis weight of the surface layer and / or sublayer compared to conventional Manila cartons, or may not include sublayers. At this time, the present invention includes inexpensive low-grade pulp pulp such as corrugated cardboard pulp, waste pulp pulp, ground pulp, etc., by the basis weight of the reduced sub-layer and / or surface layer to meet the basis weight of SC Manila carton as required in the art It is possible to increase the basis weight of the core layer (the first core layer and / or the second core layer). As described above, the present invention reduces the amount of expensive white paper pulp that is expensive compared to conventional SC manila cartons, and instead increases the amount of pulp of corrugated cardboard inexpensive, so that the production cost of the paperboard can be reduced.

As shown in FIG. 1, the SC Manila board according to an exemplary embodiment of the present invention includes a top coating layer 42 formed of a composition for top coating comprising heavy calcium carbonate and a binder; An undercoat layer (41) formed from a composition for undercoating comprising heavy calcium carbonate, precipitated calcium carbonate and a binder, wherein the precipitate calcium carbonate has an average particle diameter of 1 to 5 mu m; A surface layer 10 comprising white ledger pulp; A ground layer (20) comprising a ground pulp, a pulp pulp pulp and a corrugated cardboard pulp; Wherein the core layer 20, the surface layer 10, the undercoat layer 41 and the topcoat layer 42 are sequentially formed on the back layer 30, Respectively. Here, the core layer 20 may be a multi-layered structure of one layer or two or more layers. For example, as shown in FIG. 2, a first core layer (including ground pulp, pulp pulp and corrugated cardboard pulp 21 and a second core layer 22 comprising pulp corrugated pulp.

As shown in FIG. 2, the SC manila sheet according to another embodiment of the present invention includes a top coating layer 42 formed of a composition for top coating comprising heavy calcium carbonate and a binder; An undercoat layer (41) formed from a composition for undercoating comprising heavy calcium carbonate, precipitated calcium carbonate and a binder, wherein the precipitate calcium carbonate has an average particle diameter of 1 to 5 mu m; A surface layer 10 comprising white ledger pulp; A ground layer (20) comprising a ground pulp, a pulp pulp pulp and a corrugated cardboard pulp; A sublayer (50) comprising waste newspaper pulp; And a backside layer 30 comprising waste newspaper pulp wherein a core layer 20, a surface layer 10, an undercoat layer 41, a sublayer 50 and a top coat layer 30 are formed on the back layer 30, (42) are sequentially stacked. Here, the core layer 20 may be a multi-layered structure of one layer or two or more layers. For example, as shown in FIG. 2, a first core layer (including ground pulp, pulp pulp and corrugated cardboard pulp 21 and a second core layer 22 comprising pulp corrugated pulp.

(1)

The SC Manila carton of the present invention comprises a surface layer 10 comprising white high pulp as shown in Figs.

The surface layer 10 is a layer that affects the strength and whiteness of SC Manila paperboard, and includes white ledger pulp as paper stock.

The basis weight of such a surface layer is not particularly limited, and may be about the surface layer basis weight of a SC Manila paperboard known in the art. However, in the case of the present invention, since the whiteness and opacity of the paperboard can be improved due to the hiding power of the undercoat layer, the basis weight of the surface layer 11 can be controlled to be less than the basis weight of the conventional SC Manila paperboard. For example, the basis weight of the surface layer can be adjusted to about 10 to 30 g / m 2 on the basis of a basis weight of SC Manila carton of 300 g / m 2.

The white highland paper pulp is a pulp obtained by using white highland paper as a raw material, and the ink is removed.

The surface layer 10 may include chemical pulp such as virgin pulp, for example, L-BKP, other than the white paper high-purity pulp as a stock material. At this time, the content of the non-pulp pulp is not particularly limited, but if it is about 10 to 50% by weight based on the total weight of the pulp, the strength of the surface layer can be further improved.

(2) Undercoat layer

As shown in FIGS. 1 and 2, the SC Manila board of the present invention has an undercoating layer 41 formed on one surface of the surface layer 10 described above. The undercoat layer 41 is formed of a composition for undercoating comprising precipitated calcium carbonate, heavy calcium carbonate and a binder. By including such an undercoat layer, the SC Manila carton of the present invention can economically improve whiteness, opacity and printability.

Precipitated calcium carbonate (PCC) is generally prepared by chemical treatment of limestone. It has various particle sizes, shapes, and particle size distribution according to the production conditions. However, in the present invention, precipitated calcium carbonate having an average particle size of about 1 to 5 탆 is mixed with the following heavy calcium carbonate and used as a pigment in order to economically improve whiteness, opacity and printability in comparison with conventional SC manila paperboard do. If the average particle size of the precipitated calcium carbonate is less than about 1 탆, the light may not be scattered properly and the whiteness and opacity may not be improved, so that the color of the core layer may not be properly concealed, The fluidity of the composition for undercoating is lowered and the workability may be lowered. On the other hand, when the average particle size of the precipitable calcium carbonate exceeds about 5 탆, it is difficult to maintain the shape and particle size (size) of the particles due to the breakage of the particles at the time of use as a component of the coating composition, And the light scattering does not occur properly, so that the whiteness and opacity do not improve.

Thus, the undercoat layer 41 formed using the precipitated calcium carbonate can effectively hide the color of the core layer, and thus, the SC Manila board of the present invention can be formed by using the following top coat layer 42 alone or the following top coat layer 42 The whiteness and opacity can be further improved compared to the conventional double SC SC Manila carton. In addition, the pore characteristics of the undercoat layer can be changed by the precipitated calcium carbonate having an average particle diameter of about 1 to 5 mu m, so that the printability of the SC manila carton can be further improved.

The shape of the precipitated calcium carbonate is not particularly limited, but in the case of a non-circular or non-circular shape such as an acicular shape, a polygonal shape or the like, the scattering of light is better caused by scattering of diffused light, so that opacity and whiteness can be further improved.

The composition for undercoating includes ground calcium carbonate (GCC) other than the above-mentioned precipitated calcium carbonate as a pigment. The heavy calcium carbonate is a white pigment prepared by physically directly pulverizing / grinding crystalline limestone having high whiteness and then classifying it. This heavy calcium carbonate not only improves the opacity and whiteness of SC Manila paperboard but also enhances the opacity and whiteness of the SC Manila paperboard as well as the amount of pulp in the surface layer of the SC Manila paperboard (pores formed by pulp- Since the surface area of the surface layer is improved by filling a small area, the printability can be improved.

The mixing ratio of the precipitable calcium carbonate to the heavy calcium carbonate in the composition for undercoat is not particularly limited. However, when the precipitated calcium carbonate and heavy calcium carbonate are contained in a weight ratio of 10:50 to 50:90, surface characteristics such as printability and whiteness can be optimized.

The composition for undercoating includes a binder. The binder can impart not only the adhesion between the calcium carbonate as a pigment but also the adhesion between the surface layer and calcium carbonate, and can give excellent printability.

The binder usable in the present invention is not particularly limited and includes, for example, a styrene-butadiene-based carboxy succession polymer latex obtained by copolymerizing an aliphatic conjugated diene monomer, an aromatic vinyl monomer and an ethylenically unsaturated carboxylic acid monomer with another copolymerizable monomer, Latex latex, vinyl acetate latex and the like, and starch, casein and the like can be used as auxiliary binders. Particularly, when the styrene-butadiene-based carboxy succession polymer latex is used as the binder, the water resistance and printability of the SC manila carton can be improved.

The content of the binder is not particularly limited, but is about 5 to 15 parts by weight, preferably about 8 to 12 parts by weight, based on 100 parts by weight of the mixture of precipitated calcium carbonate and heavy calcium carbonate, It is possible to further improve the adhesion between the calcium and the surface layer and further improve the printability of the SC Manila paperboard.

The undercoating composition may contain at least one additive such as a dye, a lubricant, an insolubilizer, an antiseptic, caustic soda (NaOH), a flow control agent, a dispersant, a thickener, and the like.

The content of the additive is not particularly limited and may be appropriately adjusted according to the kind of additive, for example, about 0.01 to 10 parts by weight based on 100 parts by weight of a mixture of precipitated calcium carbonate and heavy calcium carbonate.

The total basis weight of the undercoat layer and the following top coat layer is not particularly limited, but when it is about 22 to 36 g / m 2, the whiteness and opacity can be improved and the printability can be improved. The ratio of the thickness of the undercoat layer to the topcoat layer is not particularly limited. However, when the thickness is 1 to 2: 2 to 1, the color or spots of the core layer may be more effectively concealed and the printability may be further improved.

(3) Top coating layer

In the SC manila carton of the present invention, a top coating layer 42 is formed on the undercoat layer 41 described above. The top coating layer 42 comprises a top coating layer 42 comprised of a composition for top coating comprising heavy calcium carbonate and a binder. By including this top coating layer 42, the SC Manila carton of the present invention can be further improved in whiteness, opacity and printability.

In the composition for top coating, heavy calcium carbonate used in the above-mentioned composition for undercoating and heavy calcium carbonate and binder similar to the binder are used. However, if the amount of the binder is about 5 to 15 parts by weight, preferably about 8 to 12 parts by weight, based on 100 parts by weight of the heavy calcium carbonate, The adhesion property between the calcium carbonate and the surface layer can be further improved and the printability of the SC Manila paperboard can be further improved.

 The composition for top coating may also contain at least one additive such as a dye, a lubricant, an insolubilizer, an antiseptic agent, NaOH, a flow control agent, a dispersant, and a thickener, if necessary. The content of the additive is not particularly limited and may be appropriately adjusted depending on the kind of additive, for example, about 0.01 to 10 parts by weight based on 100 parts by weight of heavy calcium carbonate.

(4) Core layer

As shown in FIG. 1, the SC Manila carton of the present invention has a core layer 20 formed on the other surface of the surface layer 10 described above. Since the core layer 20 is a layer for securing the thickness of the paperboard, it includes low-grade pulp pulp obtained after a cleaning process to remove impurities. That is, as the low grade pulp pulp used in the core layer, not only the pulp from which the ink is removed but also the pulp from which the ink is not removed can be used.

The core layer 20 is a layer comprising at least one pulp pulp selected from the group consisting of ground pulp, pulp pulp pulp and corrugated cardboard pulp. Herein, the ground pulp is pulp made from ground material, the corrugated cardboard pulp is pulp made from corrugated corrugated paper, and the pulp pulp made from pulp paper is used as a raw material, Including those not removed.

The core layer 20 may be composed of a single layer or a multilayer of two layers or three layers depending on a cardboard manufacturing facility, and the role of the single layer or the multilayer is to secure the thickness of the cardboard as described above.

For example, the core layer 20 may include a first core layer 21 and a second core layer 22 as shown in FIG. The first core layer 21 is a ground layer including at least one pulp pulp selected from the group consisting of ground pulp, pulp pulp pulp and corrugated cardboard pulp, and the second core layer is a ground layer including pulp corrugated pulp.

The basis weight of the core layer 20 is not particularly limited, and may be about the core layer weight of the SC Manila carton known in the art. However, in the case of the present invention, the whiteness and opacity of the cardboard can be further improved by the undercoat layer 41 than in the prior art. Therefore, in the case of the present invention, even if the amount of pulp pulp in the core layer (particularly, the first core layer), particularly the amount of corrugated cardboard pulp with the lowest whiteness is further increased than before, , The color or spots of the core layer can be effectively concealed by the undercoat layer, so that the whiteness and opacity of the cardboard may not be lowered. Therefore, in the present invention, in order to reduce the production cost, the basis weight of the surface layer and / or the basis weight of the sublayer described above is reduced, or when the sublayer is not included, the basis weight of the reduced surface layer and / By increasing the basis weight of the surface layer, it is possible to adjust the basis weight of the SC Manila carton as required in the art, and also to reduce the production cost. For example, the basis weight of the core layer may be about 210 to 230 g / m 2 on a basis weight of 300 g / m 2 of the SC Manila carton, wherein the basis weight of the surface layer may be about 10 to 30 g / m 2, The basis weight may be about 10 to 30 g / m < 2 > or may not include the sub-layer.

(5)

As shown in FIG. 1, the SC Manila carton of the present invention has a back layer 30 formed on the other side of the core layer 22 in order.

The back layer 30 is a layer comprising waste newspaper pulp. The waste newspaper pulp is pulp from an old news paper (ONP) as a raw material, and the ink is removed. The strength or whiteness of the waste newspaper pulp varies depending on the quality of the waste newspaper. In particular, the whiteness of the waste newspaper pulp is between white paper waste paper pulp and waste paper waste pulp (for example, corrugated cardboard pulp). The backing layer containing such waste newsprint pulp can conceal the color or spots of the core layer (especially the second core layer), so that when the SC Manila carton is used as the backing of the packaging box, There is less feeling of mixing of foreign substances. In recent years, there is a case where printing is performed on the inner side of a carton box made of SC Manila paperboard. By using a ground layer including waste newspaper pulp as a back layer, the smoothness can be improved and the printing operation can be facilitated.

However, the backside layer 30 may optionally include corrugated cardboard pulp and / or virgin pulp (e.g., BKP) other than the waste newspaper pulp. By mixing pulp other than pulp newspaper, the color of the back layer can be varied from brown to gray, while adjusting the smoothness. The ratio of mixing the waste newspaper pulp with the waste corrugated pulp and / or the non-waste paper pulp is appropriately adjusted in consideration of the desired color and smoothness.

The basis weight of the back layer 30 is not particularly limited and can be on the order of the back layer basis weight of the SC Manila paperboard known in the art. For example, the basis weight of the backing layer may be on the order of 25 to 35 g / m 2 based on a basis weight of SC Manila carton 300 g / m 2.

(6) Sub-layer

The SC Manila carton of the present invention is characterized in that a sublayer 50 is provided between the surface layer 10 and the core layer 20 (or between the surface layer 20 and the first core layer 21) May be intervening.

The sub-layer 50 is formed between the surface layer 10 and the core layer 20 (or the first core layer 21) so that it is visible through the transparent portion of the surface layer 10 It primarily serves to conceal the color and spots of the heart layer. The sub layer 50 also alleviates the difference in whiteness and strength difference between the surface layer 10 and the core layer 20 (or between the surface layer 10 and the first core layer 21). Thus, the sub-layer 50 includes waste newsprint pulp having a degree of whiteness between the white high-prize pulp and the low-grade pulp pulp (for example, corrugated cardboard pulp).

Such sub-layer 20 has been essentially included in conventional SC Manila carton to conceal the color, spots, etc. of the core layer. However, in the present invention, since the undercoat layer 41 can effectively hide the color, spots, and the like of the core layer without including the sub-layer, the sub-layer 20 can be selectively included.

The basis weight of the sub-layer (50) is not particularly limited and may be about the sub-layer basis weight of the SC Manila carton known in the art. However, in the present invention, since the color, spots, etc. of the core layer can be effectively concealed by the precipitated calcium carbonate having a specific particle diameter in the undercoat layer 41, unlike the conventional SC manila carton, the basis weight of the sub- Can be reduced to about 10 to 30 g / m 2 (based on a basis weight of SC Manila carton 300 g / m 2) and may not further include the sub-layer 50.

The SC Manila carton of the present invention can be manufactured according to a method of manufacturing a paperboard known in the art.

For example, the SC Manila carton may comprise forming a surface layer, a core layer and a back layer, and optionally, a stuff of each sublayer; Forming a sheet by injection dewatering the stocks of the respective layers; Obtaining a multilayer sheet in which the paper sheets are successively laminated so that a core layer and a surface layer (or a core layer, a sublayer, and a surface layer on the back layer) are sequentially laminated on the back layer; Pressing the multilayer sheet by forced dehydration using a press, followed by drying by heating at 60 to 180 ° C; Flattening the surface of the dried multilayer sheet while adjusting the thickness of the paper web using a calendar; Applying a top coating composition comprising heavy calcium carbonate and a binder to the surface layer to form a top coating layer; And forming an undercoat layer on the top coat layer by applying a composition for undercoating comprising heavy calcium carbonate, precipitated calcium carbonate and a binder, wherein the precipitated calcium carbonate has an average particle diameter of 1 to 5 탆, , ≪ / RTI >

Wherein each of the steps of forming the fibers comprises dissociating the waste paper into individual fibers under a predetermined condition known in the art; A cleansing step of removing dirt and foreign matter from pulp pulp obtained in the dissociating step using a cleaner and a screen; A deinking step of adding ink remover known in the art to the pulp pulp obtained through the rectifying step to remove the ink; And a defibrillation step of mechanically cutting the pulp pulp from which ink has been removed through the deinking step or fibrillating the pulp by physically and chemically tearing it with a fiber. Through such a formation step of the paper, it is possible to obtain white high-purity paper pulp, ground paper pulp, waste paper pulp, waste corrugated cardboard pulp, and waste newspaper paper pulp, which can be used as materials for each layer.

Meanwhile, the present invention provides a coating composition for paper which comprises heavy calcium carbonate, precipitated calcium carbonate and a binder, wherein the precipitated calcium carbonate has an average particle size of 1 to 5 탆. The coating composition for a board includes precipitated calcium carbonate having an average particle size of about 1 to 5 占 퐉, thereby making it possible to economically improve whiteness and opacity of a cardboard while improving printability.

At this time, the content of each component of the above-mentioned coating composition for a board, the content of the above components, the particle diameter and the like are the same as those described above in the composition for undercoating.

Hereinafter, the present invention will be described in detail with reference to examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

≪ Example 1 >

1-1. Preparation of composition for undercoating

Precipitated calcium carbonate (average particle size: about 3 mu m) and heavy calcium carbonate were mixed in a weight ratio of 10: 90. To 100 parts by weight of this calcium carbonate mixture were added 10 parts by weight of LATEX 703, 0.03 part by weight of caustic soda (NaOH 50%), Slacon 0.03 as a preservative, 0.12 part by weight of Sterocol as a flow control agent, 0.0075 part by weight of blue dye, Was added to prepare a composition for undercoating.

1-2. Preparation of Composition for Top Coating

100 parts by weight of heavy calcium carbonate, 10 parts by weight of LATEX 706, 0.3 part by weight of Nopcote 155 as a lubricant, 0.2 parts by weight of Parez 825 as a water-proofing agent, 0.15 part by weight of caustic soda (NaOH 50%), 0.03 part by weight of Slacon as a preservative, 0.05 part by weight of Sterocol, 0.0075 part by weight of Blue dye and 0.014 part by weight of Violet dye were added to prepare a composition for top coating.

1-3. Manufacturing of SC Manila carton

A surface layer (basis weight: about 17.3 g / m 2) was formed using white paper pulp and a core layer (basis weight: about 218.5 g / m 2) was formed using ground pulp, pulp paper pulp and corrugated pulp paper, The back layer (basis weight: about 30 g / m < 2 >) was formed using pulp. Thereafter, the layer is folded so that the core layer and the surface layer are laminated on the back layer, and then forced dehydration is performed using a press, followed by drying at about 60 to 180 DEG C, and the thickness of the paper is adjusted using a calender And the surface was flattened. Subsequently, the undercoat layer composition prepared was applied to the surface layer to form an undercoat layer, and then the topcoat layer composition prepared on the undercoat layer was applied to form a topcoat layer, thereby preparing a SC manila carton.

≪ Comparative Example 1 &

The procedure of Example 1-1 was repeated except that 100 parts by weight of heavy calcium carbonate was used instead of 100 parts by weight of the mixture of precipitated calcium carbonate and heavy calcium carbonate used in the preparation of the undercoating composition in Example 1-1. To prepare a SC Manila carton.

≪ Experimental Example 1 > - Evaluation of physical properties of SC Manila carton

The physical properties of the SC Manila carton prepared in Example 1 and Comparative Example 1 were evaluated as follows, and the results are shown in Table 1 below.

(1) Weighing of specimen

The SC Manila paperboard prepared in each of Example 1 and Comparative Example 1 was cut to a length of 1 m or more and then cut into a size of 400 mm x 250 mm to obtain a test piece 1 and a control specimen 1. Thereafter, the weight of each specimen was measured with an electronic balance, and then the basis weight was calculated according to the following equation (in the following equation, the unit of the width and height is m).

As a result of the measurement of the basis weight, the actual basis weight of specimen 1 was 300.1 g / m2, and the actual basis weight of the control specimen was 300 g / m2.

(2) Measurement of thickness of specimen

As a result of the measurement of the specimen 1 and the control specimen 1 prepared using the thickness gauge, the thickness of the specimen 1 was 375 탆 and the thickness of the control specimen was 368 탆.

(3) Water content: The water content was measured according to the test method KSMISO 287 (pre-drying method).

(4) Whiteness: Whiteness was measured according to Test Method KSM 7026.

(5) Glossiness: The glossiness was measured according to Test Method KSMISO8254-1.

(6) Bekk Smoothness: Smoothness was measured according to Test Method KSM7028.

(7) Absorbency: Absorbency was measured according to Test Method KSM7054.

(8) Printing layer separation: Layer separation properties were measured according to Test Method KSM7066.

(9) Mottling

Three specimens 1 and one control specimen 1 were prepared. After transferring the ink (norak: blue = 7: 1 volume ratio) to the ink roll of the printing machine, the ink was spun for about 5 to 10 minutes. Thereafter, printing was carried out on the first specimen 1, and the second specimen 1 and the third specimen 1 were printed in the same manner. Thereafter, the ink absorption state of each printed specimen was evaluated by the five-point method as described below, in comparison with the SC-Manila carton (hereinafter referred to as "reference specimen") sold by the present company. The evaluation results are shown in Table 1 below.

- superior to the reference specimen: 5 points

- better than the reference specimen: 4 points

- Standard Specimen Level: 3 points

- Less than the reference specimen: 2 points

- Defective: 1 point

(10) Curl height: Curl property was measured according to the test method KSA1050.

Example 1 Comparative Example 1 Reference value Moisture content (%) 5.5 5.9 6.5 Surface whiteness (%) 79.2 80.3 76 or more Glossiness (%) 57 58 55 or more PPS smoothness of the surface (탆) 2.5 2.3 2.5 or less Absorption (g / m ² ) 66 61 60 or less Print layer separation (Times) 27 28 20 or more Motting (5-point method) 3 3.5 3.0 or higher Curl height (mm) cn12 cn10 15 or less

As can be seen from the above Table 1, the SC Manila carton produced in Example 1 was similar in physical properties to the SC Manila carton prepared in Comparative Example 1, and in particular, the surface whiteness and smoothness satisfied the values required in the art .

From the above, it was confirmed that the SC Manila paperboard according to the present invention has an excellent whiteness and smoothness even if the basis weight of the surface layer is reduced and the sublayer is not included or the basis weight of the sublayer is reduced.

≪ Experimental Example 2 > - Measurement of strength of SC Manila carton

The strengths of the SC Manila cartons produced in Example 1 and Comparative Example 1 were evaluated as follows, and the results are shown in Table 2 below.

(1) Intrathoracic degree: The degree of throat was measured using a KSM7065-MIT tester.

(2) Stiffness: The stiffness was measured according to the test method KSMISO5629.

(3) Tear strength: Tear strength was measured according to Test Method KSMISO1974.

Example 1 Comparative Example 1 Reference value My theft
Times (1Kg) MD 9 15 - CD 9 12 - Stiffness
(gf.cm) MD 105 113 - CD 55 47 - Tear strength (kg / cm) 0.7 0.8 0.7 or more

As can be seen from the above Table 1, the SC Manila carton produced in Example 1 had similar strength to the SC Manila carton prepared in Comparative Example 1.

From this, it can be seen that the SC Manila paperboard according to the present invention reduces the basis weight of the surface layer, and further, the strength of the cardboard does not decrease even if the sublayer is not included or the basis weight of the sublayer is reduced.

≪ Experimental Example 3 > - Spot test of SC Manila carton

The spots of the SC Manila carton produced in Example 1 and Comparative Example 1 were evaluated as follows, and the results are shown in Table 3 below.

(1) Color spots

The SC Manila carton prepared in Example 1 was cut to a size of 1 m X 1 m to prepare a test piece 2. Thereafter, the prepared specimen 2 was completely immersed in water, and the number of spots (size: more than 5 mm 2) visible on the back surface of the specimen 2 were visually observed at a position 40 cm away from the specimen 1, and the results are shown in Table 3 below . At this time, the SC Manila carton produced in Comparative Example 1 was used as the control specimen 2.

(2) Surface spots

The SC Manila carton prepared in Example 1 was cut to a size of 1 m X 1 m to prepare a test piece 3. Thereafter, the number of spots (size: 1 mm 2 or more) visible on the surface of the specimen 3 were counted visually at a position 40 cm away from the specimen 1, and the results are shown in Table 3 below. At this time, the SC Manila carton produced in Comparative Example 1 was used as the control specimen 3.

(3) oil spots

The SC Manila carton prepared in Example 1 was cut to a size of 1 m X 1 m to prepare a test piece 4. Thereafter, the back surface of the prepared specimen 4 was soaked in gasoline, and the number of spots (size: 5 mm 2 or more) visible on the back surface of the specimen 4 was counted visually from the position 40 cm away from the specimen 1. . At this time, SC Manila paperboard prepared in Comparative Example 1 was used as the control sample 4.

Example 1 Comparative Example 1 Reference value Color spots 6 6 below 10 Yellow spot 0 0 0 or less Oil spots 9 7 below 10

As can be seen from the above Table 1, the SC Manila carton produced in Example 1 concealed the color or spots of the core layer similar to the SC Manila carton prepared in Comparative Example 1.

From this it can be seen that the SC Manila carton according to the invention can reduce the basis weight of the surface layer and thus effectively hide the color or spot of the sublayer even if it does not contain the sublayer or reduces the basis weight of the sublayer.

<Experimental Example 4> - Sensory evaluation of SC Manila carton

The scent of the SC Manila carton produced in each of Example 1 and Comparative Example 1 was evaluated as follows.

As a result of the evaluation, all SC Manila cartons of Example 1 and Comparative Example 1 were odorless.

10: surface layer, 20: core layer,
21: first core layer, 22: second core layer,
30: rear layer, 41: undercoat layer,
42: top coating layer, 50: sub-layer

Claims (9)

A top coating layer formed of a composition for top coating comprising heavy calcium carbonate and a binder;
An undercoat layer formed from a composition for undercoating comprising heavy calcium carbonate, precipitated calcium carbonate and a binder, wherein the precipitated calcium carbonate has an average particle diameter of 1 to 5 mu m;
A surface layer comprising white ledger pulp;
A core layer comprising one selected from the group consisting of ground pulp, pulp pulp pulp and corrugated cardboard pulp; And
Backside layer containing waste newspaper pulp
Wherein a core layer, a surface layer, an undercoat layer, and a top coat layer are sequentially stacked on the rear layer,
Wherein the composition for undercoat comprises heavy calcium carbonate and precipitated calcium carbonate in a weight ratio of 50 to 90:50 to 10,
Wherein the binder content of the top coating layer and the undercoating layer is 8 to 12 parts by weight based on 100 parts by weight of the mixture of the precipitated calcium carbonate and the heavy calcium carbonate,
The total basis weight of the top coating layer and the undercoating layer is 22 to 36 g / m 2 based on a basis weight of 300 g / m 2 of a Manila board,
The basis weight of the surface layer is 10 to 30 g / m 2 based on a basis weight of 300 g / m 2 of a Manila board,
Wherein the basis weight of the core layer is 210 to 230 g / m 2 based on a basis weight of 300 g / m 2 of the Manila carton. The method according to claim 1,
Further comprising a sublayer between the surface layer and the core layer, the sublayer comprising waste newspaper pulp. 3. The method according to claim 1 or 2,
The core layer
A first core layer comprising ground pulp, pulp pulp pulp and corrugated cardboard pulp; And
A second core layer comprising pulp corrugated pulp;
&Lt; RTI ID = 0.0 &gt; SC. &Lt; / RTI &gt; The SC Manila board according to claim 1 or 2, wherein the shape of the precipitated calcium carbonate is acicular or polygonal. delete delete 3. The SC Manila board according to claim 2, wherein the sublayer has a basis weight of 10 to 30 g / m 2 based on a basis weight of 300 g / m 2 of the Manila board. A top coating layer formed of a composition for top coating comprising heavy calcium carbonate and a binder;
An undercoat layer formed from a composition for undercoating comprising heavy calcium carbonate, precipitated calcium carbonate and a binder, wherein the precipitated calcium carbonate has an average particle diameter of 1 to 5 占 퐉;
A surface layer comprising white top paper pulp;
A core layer comprising one selected from the group consisting of ground pulp, pulp pulp pulp and corrugated cardboard pulp; And
Backside layer containing waste newspaper pulp
Wherein a core layer, a surface layer, an undercoat layer, and a top coat layer are sequentially stacked on the rear layer,
Wherein the composition for undercoat comprises heavy calcium carbonate and precipitated calcium carbonate in a weight ratio of 50 to 90:50 to 10,
Wherein the binder content of the top coating layer and the undercoating layer is 8 to 12 parts by weight based on 100 parts by weight of the mixture of the precipitated calcium carbonate and the heavy calcium carbonate,
The total basis weight of the top coating layer and the undercoating layer is 22 to 36 g / m 2 based on a basis weight of 300 g / m 2 of a Manila board,
The basis weight of the surface layer is 10 to 30 g / m 2 based on a basis weight of 300 g / m 2 of a Manila board,
Wherein the basis weight of the core layer is 210 to 230 g / m 2 based on a basis weight of 300 g / m 2 of a Manila board. delete

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