Coated paper and packaging paper

Abstract

To provide coated paper that is less prone to contents sticking and has excellent suitability for bag making. [Solution] A paper substrate and an anti-adhesion layer on at least one of its outermost surfaces, The shopper-ligler filtration rate of the pulp constituting the aforementioned paper substrate is 50°SR or more and 90°SR or less. The proportion of softwood kraft pulp to total pulp is 40% by weight or more. The coating amount (dry weight) per side of the aforementioned anti-adhesion layer is 3 g / m². 2 That's all. The aforementioned anti-adhesion layer is a coated paper having a static friction coefficient of 0.3 or less and a water contact angle (10 seconds) of 85° or more.

Description

[Technical Field] 【0001】 The present invention relates to coated paper that is less likely to have contents stick to it and has excellent suitability for bag making, and to packaging paper having this coated paper. [Background technology] 【0002】 In recent years, due to environmental concerns, the replacement of film with paper in packaging materials has been considered. Film excels in multiple barrier properties such as water resistance, oil resistance, water repellency, water vapor barrier properties, moisture permeability, and oxygen barrier properties, as well as suitability for bag making, whereas paper has not yet reached the same level of performance as film. Patent documents 1 and 2 describe a material having a heat-seal layer on one side and a moisture permeability of 1,000 g / m². 2 ·2,000g / m over 24hr 2 • Less than 24hr or with a breathability of 300g / m² 2 ·1,200g / m over 24hr 2 • Heat-sealable paper with a shelf life of 24 hours or less is specified. Paper-based packaging materials intended as alternatives to plastic films have primarily been developed with the aim of enhancing barrier properties, and their suitability for packaging has not been adequately considered. Furthermore, their moisture permeability has not been sufficient to be considered adequate as a film substitute. [Prior art documents] [Patent Documents] 【0003】 [Patent Document 1] Japanese Patent Publication No. 2022-024905 [Patent Document 2] Japanese Patent Publication No. 2023-107689 [Overview of the project] [Problems that the invention aims to solve] 【0004】 Rice products such as onigiri (rice balls) and norimaki (sushi rolls) are sold wrapped in film at convenience stores and supermarkets. When we considered replacing this film with paper, we found that the rice and seaweed would stick to the paper. The present invention aims to solve this problem by providing coated paper that is less prone to contents sticking to it and has excellent suitability for bag making. [Means for solving the problem] 【0005】 The means for solving the problems of the present invention are as follows. 1. A paper substrate and an anti-adhesion layer on at least one of its outermost surfaces, The shopper-ligler filtration rate of the pulp constituting the aforementioned paper substrate is 50°SR or more and 90°SR or less. The proportion of softwood kraft pulp to total pulp is 40% by weight or more. The coating amount (dry weight) per side of the aforementioned anti-adhesion layer is 3 g / m². 2 That's all. The coated paper is characterized in that the anti-adhesion layer has a static friction coefficient of 0.3 or less and a water contact angle (10 seconds) of 85° or more. 2. The basis weight of the paper substrate is 60 g / m². 2 The coated paper according to 1, characterized in that it is as follows. 3. The moisture permeability of the coated paper is 150 g / m². 2 The coated paper according to 1. or 2., characterized in that it is less than or equal to / day. 4. Coated paper according to any one of 1 to 3, characterized in that its longitudinal tensile strength is 1.4 kN / m or more. 5. Coated paper according to any one of 1 to 4, characterized in that the rigidity in the vertical direction (handle meter method) is 1500 mN / 100 mm or less. 6. Having coated paper as described in any of 1. to 5. Packaging paper characterized by being suitable for packaging rice, bread, Japanese sweets, Western sweets, or fried foods. [Effects of the Invention] 【0006】 The coated paper of the present invention has a low sticking property of the contents. The coated paper of the present invention has good cut resistance during bag-making processing, is less likely to wrinkle or break during pillow bag-making processing, and has excellent bag-making suitability. The coated paper of the present invention with low moisture permeability is less likely to allow moisture to penetrate from the outside and less likely to dry out by losing moisture from the inside, and has excellent quality retention of the contents. The coated paper of the present invention can be suitably used as packaging paper for foods such as rice balls, nori rolls, sandwiches, etc. 【Mode for Carrying Out the Invention】 【0007】 The coated paper of the present invention has an anti-adhesion layer on at least one of the outermost surfaces and a paper base material. The Schopper-Riegler drainage degree of the pulp constituting the paper base material is 50°SR or more and 90°SR or less. The proportion of softwood kraft pulp to all pulp is 40% by weight or more. The coating amount (dry weight) per side of the anti-adhesion layer is 3 g / m 2 or more. The anti-adhesion layer has a static friction coefficient of 0.3 or less and a water contact angle (10 seconds) of 85° or more. 【0008】 “Paper base material” (Pulp) As the pulp, chemical pulps of wood such as softwood bleached kraft pulp (NBKP), softwood unbleached kraft pulp (NUKP), hardwood bleached kraft pulp (LBKP), hardwood unbleached kraft pulp (LUKP), sulfite pulp (SP), etc., mechanical pulps of wood such as ground pulp (GP), refiner ground pulp (RGP), stone ground pulp (SGP), chemiground pulp (CGP), semi-chemical pulp (SCP), thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP), etc., non-wood pulps obtained from kenaf, bagasse, bamboo, hemp, straw, etc., waste paper as a raw material, and waste paper pulp obtained by removing the ink contained in the waste paper in the deinking process can be appropriately blended and used. Among these, chemical pulps such as LBKP and NBKP, which are less likely to cause foreign matter mixing, are preferable, and it is also preferable that the blending amount of waste paper pulp is small. Specifically, the proportion of chemical pulp to total pulp is preferably 80% by weight or more, more preferably 90% by weight or more, even more preferably 95% by weight or more, and particularly preferably 100% by weight. Furthermore, the proportion of recycled paper pulp to total pulp is preferably 10% by weight or less, more preferably 5% by weight or less, even more preferably 1% by weight or less, and most preferably none. 【0009】 The paper substrate of the present invention has a softwood kraft pulp (NBKP, NUKP) content of 40% by weight or more relative to the total pulp. Having a softwood kraft pulp content of 40% by weight or more relative to the pulp makes it easy to obtain sufficient tear strength and tensile strength during bag manufacturing. The softwood kraft pulp content relative to the total pulp can also be 50% by weight or more, 60% by weight or more, 70% by weight or more, 80% by weight or more, 90% by weight or more, 95% by weight or more, 100% by weight or more, etc. 【0010】 (Other additives) Other additives may be added to the paper substrate as needed. Examples of additives include fillers, pigments, sizing agents, coagulants, fluorescent whitening agents, aluminum sulfate, yield enhancers, water drainage enhancers, dry strength enhancers, wet strength enhancers, coloring dyes, coloring pigments, and water-resistant agents, which can be used individually or in combination. 【0011】 (Freeness) The pulp forming the paper substrate of the present invention has a Schopper-Riegler drainage degree of 50°SR or more and 90°SR or less. The Schopper-Riegler drainage degree is a numerical value indicating the degree of beating of the pulp, and the higher the value, the more advanced the beating. Note that the pulp forming the paper substrate means all the pulp contained in the paper substrate. If the Schopper-Riegler drainage degree of the paper substrate is less than 50°SR, since the strength of the paper substrate is low, when applying the resin coating liquid, the occurrence of breakage of the paper substrate and the deterioration of the texture of the paper substrate are显著 manifested, and unevenness in various performances may occur. Further, when the Schopper-Riegler drainage degree exceeds 90°SR, uneven liquid absorption occurs on the paper substrate when applying the resin coating liquid, and unevenness in various performances may occur. This Schopper-Riegler drainage degree is preferably 50°SR or more and 80°SR or less, and more preferably 50°SR or more and 75°SR or less. Also, when the drainage degree is within the above range, the dimensional stability of the paper substrate is also excellent. 【0012】 (Manufacturing method) The papermaking method of the paper substrate can be manufactured using a method used in known papermaking applications. Specifically, it can be manufactured using a fourdrinier paper machine, a cylinder paper machine, a twin-wire paper machine, an on-top hybrid paper machine, a gap former machine, etc. 【0013】 (Calendering treatment) In order to increase the density and smoothness of the paper substrate and prevent the penetration of the coating liquid, it is preferable to perform calendering treatment. The type of calender is not particularly limited, and a smoothing treatment device such as a normal super calender, a gloss calender, a soft calender, a hot calender, a shoe calender, etc. can be used. The paper substrate of the present invention can be surface-treated with a calender such as a super calender or a high-temperature soft nip calender. 【0014】 (Basis weight of the paper substrate) The basis weight of the paper substrate is not particularly limited, but from the viewpoint of bag-making processability, it is preferably 60 g / m 2 or less. When the basis weight is 60 g / m 2Larger paper sizes result in thicker paper and higher rigidity, which can lead to wrinkles and tears during bag making, and may also result in poorer cutting performance. There is no specific lower limit on the basis weight, but it should be 20 g / m². 2 This is preferable. Lower basis weight substrates are more prone to uneven adhesion of the coating liquid, which is thought to be due to the formation of the pulp fibers, and this causes inconsistencies in various performance characteristics. The basis weight of the paper substrate is 55 g / m². 2 The following is more preferable: 50 g / m 2 The following is even more preferable: 45 g / m 2 The following is more preferably, and even more preferably, 40 g / m² 2 The following applies: 【0015】 (Paper thickness of paper base material) The paper substrate thickness is preferably 30 μm or more. Cutting performance tends to be poor if the paper thickness is less than 30 μm. The upper limit for the paper substrate thickness can be approximately 50 μm. 【0016】 (Air permeability resistance of paper substrate) The paper substrate preferably has a Wang-Gan air permeability resistance of 500 seconds or more so that the resin coating liquid remains on the surface of the paper substrate. More preferably, the Wang-Gan air permeability resistance of the paper substrate is 800 seconds or more, and even more preferably 1100 seconds or more. There is no particular upper limit to the Wang-Gan air permeability resistance of the paper substrate, but for example, it is about 10,000 seconds. 【0017】 "Anti-adhesion layer" The anti-adhesion layer is a resin coating layer provided on at least one of the outermost surfaces of the paper substrate, having a static friction coefficient of 0.3 or less and a water contact angle (10 seconds) of 85° or more. In the coated paper of the present invention, the anti-adhesion layer may be provided on both outermost surfaces of the paper substrate, but it is preferable to provide it on only one surface from the viewpoint of preventing blocking. Furthermore, the coated paper of the present invention may also have other layers between the paper substrate and the anti-adhesion layer, such as a sealing layer, an adhesive layer, a gas barrier layer, a water vapor barrier layer, a pigment coating layer, an oil-resistant layer, or a water-resistant layer. 【0018】 In the present invention, the anti-adhesion layer has a static friction coefficient of 0.3 or less and a water contact angle (10 seconds) of 85° or more. The coated paper of the present invention has an anti-adhesion layer on its outermost surface that satisfies the above-mentioned static friction coefficient and water contact angle (10 seconds), thereby exhibiting excellent resistance to the adhesion of contents. For this reason, the coated paper of the present invention can be used as packaging paper for items that tend to stick. In particular, it can be used particularly suitably for packaging sticky foods such as rice dishes like onigiri and norimaki; bread such as sandwiches and sweet buns; Japanese sweets such as dango, daifuku, dorayaki, manju, kusamochi, mochi, yokan, monaka, castella, karinto, and gyuhi; Western sweets such as madeleines, financiers, donuts, canelés, caramel, and chocolate; and fried foods such as karaage, katsu, and croquettes. This is because the food can be removed from the packaging without sticking to the packaging paper, making it easy to remove the food without damaging its shape during packaging. 【0019】 (Coefficient of friction) The static friction coefficient of the anti-adhesion layer is preferably 0.25 or less, more preferably 0.2 or less, and even more preferably 0.15 or less. The coefficient of dynamic friction of the anti-adhesion layer is preferably 0.20 or less, more preferably 0.2 or less, and even more preferably 0.15 or less. When the coefficient of friction increases, the slipperiness between the coated paper and the contents decreases, making it easier for the contents to stick. 【0020】 (water contact angle) The water contact angle (10 seconds) of the anti-adhesion layer is preferably 86° or higher, more preferably 87° or higher, even more preferably 88° or higher, and even more preferably 89° or higher. When the water contact angle decreases, water penetrates the coated paper more easily, making it easier for contents to adhere via water. 【0021】 (Tape peel strength) The anti-adhesion layer preferably has a peel strength (T-type) of 0.3 N / 18 mm or less, more preferably 0.2 N / 18 mm or less, and even more preferably 0.1 N / 18 mm or less, of a single-sided adhesive tape such as Scotch tape (manufactured by 3M, Scotch® Removable Tape 811). 【0022】 (The resin contained in the anti-adhesion layer) The anti-adhesion layer is formed by coating with a resin coating liquid. The resin included in the anti-adhesion layer is not particularly limited as long as it can form an anti-adhesion layer that satisfies the static friction coefficient and water contact angle described above, but a resin with a water repellency of R5 or higher, as measured by the following method, is preferred. The water repellency of the resin is more preferably R6 or higher, even more preferably R7 or higher, even more preferably R8 or higher, even more preferably R9 or higher, and most preferably R10. ·Measurement method The undiluted coating solution was dropped onto an OHP film, and a coating layer of approximately 100 μm was prepared using a YBA type baker applicator (manufactured by Yoshimitsu Seiki Co., Ltd.) with the scale set to position 4. The sheet was then dried in a dryer at 105°C for 2 hours. The water repellency of the prepared sheet was measured in accordance with the water repellency test method (JAPAN TAPPI No. 68:2000). 【0023】 While there are no particular limitations on resins with a water repellency of R5 or higher, acrylic resins are preferred from the viewpoint of preventing sticking. An acrylic resin refers to a resin in which the molar ratio of acrylic monomers is the highest. For example, a ternary copolymer may contain a copolymer of 40 mol% acrylic monomer, 30 mol% of a second monomer, and 30 mol% of a third monomer. Examples of acrylic monomers include acrylic acid, methacrylic acid, and (meth)acrylic acid esters. The acrylic resin may be a polymer consisting only of acrylic monomers, or a copolymer containing other monomers. Examples of copolymers include styrene-acrylic copolymers and ethylene-acrylic copolymers, with styrene-acrylic copolymers being preferred. 【0024】 The resin coating liquid for forming the anti-adhesion layer may contain, in addition to a resin with a water repellency of R5 or higher, additives such as a resin with a water repellency of less than R5, a surfactant, an antifoaming agent, a surface sizing agent, a paper strength agent, a water retention agent, a thickener, a release agent, and an anti-slip agent, to the extent that it does not impair the performance of the resin. However, if a resin with a water repellency of less than R5 is included, the proportion of the resin with a water repellency of R5 or higher to the total resin is preferably 50% by weight or more, more preferably 60% by weight or more, even more preferably 70% by weight or more, even more preferably 80% by weight or more, even more preferably 90% by weight or more, and even more preferably 95% by weight or more. 【0025】 (Coating method) The method for applying the anti-adhesion layer is not particularly limited, and known coating methods can be used. Specifically, surface coating methods such as blade coaters, bar coaters, champlex coaters, gravure coaters, die coaters, curtain coaters, air knife coaters, and spray coaters can be appropriately selected and used. Among these, blade coaters, bar coaters, and air knife coaters are preferred because they easily form a uniform coating layer. The resin coating liquid may be either an aqueous system using a solvent such as water, or a solvent system using a solvent such as an organic solvent, but from a safety and health standpoint, an aqueous system is preferred. 【0026】 (Coating amount) The coating amount (dry weight) per side of the anti-adhesion layer is 3.0 g / m². 2 That's all. The coating amount is 5.0 g / m². 2 The above is more preferable, 8.0 g / m 2 The above is even more preferable. There is no particular upper limit on the coating amount, but for example, 15 g / m 2 The following is preferable. This coating amount is 15 g / m². 2 Beyond that point, performance hardly improves any further, and the cost becomes high. The anti-adhesion layer may consist of multiple layers. If there are multiple anti-adhesion layers, the total coating amount (dry weight) per side should fall within the aforementioned range; however, considering productivity, processability, etc., it is preferable to have a single coating layer. 【0027】 "Performance of coated paper" (moisture permeability) The coated paper of the present invention has a moisture permeability of 150 g / m². 2 It is preferable that the moisture permeability is 150 g / m² or less. 2 By keeping the shelf life below a certain limit (day), it is possible to prevent moisture from entering from the outside and moisture from escaping from the inside, thereby suppressing changes in the moisture content of the contents. The moisture permeability of the coated paper is 120 g / m². 2 • Less than 90 days is preferable, 90g / m² 2 More preferably less than 60 g / m² 2 • Less than 30g / m² is even more preferable. 2 • days or less is even more preferable. There is no particular limit to the moisture permeability of coated paper, but for example, 10 g / m². 2 • day, 20g / m² 2 It can be written as "day," etc. 【0028】 (Tensile strength) The coated paper of the present invention preferably has a tensile strength of 1.4 kN / m or more in the longitudinal direction (MD direction). Coated paper with a tensile strength of 1.4 kN / m or more in the longitudinal direction is less prone to breakage during bag making in a packaging machine and has excellent suitability for bag making. A tensile strength of 1.8 kN / m or more in the longitudinal direction (MD direction) is more preferably, 2.2 kN / m or more is even more preferably, and 2.5 kN / m or more is even more preferably. The tensile strength is a value measured in accordance with JIS P8113:2006. 【0029】 (Tear strength) The coated paper of the present invention preferably has a tear strength of 100 mN or more in the transverse direction (CD direction). During bag making in a packaging machine, a load is applied in the transverse direction when the contents are wrapped in the former section, making transverse tearing likely. If the transverse tear strength is 100 mN or more, breakage and tearing are less likely to occur during bag making in a packaging machine, resulting in excellent suitability for bag making. 【0030】 (Rigidity / softness of paper substrate) The coated paper of the present invention preferably has a rigidity (handle ohm meter method) of 1500 mN / 100 mm or less in the longitudinal direction (MD direction). Coated paper with a rigidity of 1500 mN / 100 mm or less is flexible, so it easily deforms to conform to the shape of the contents and is less likely to damage the contents during bag making and other processing. The rigidity (handle ohm meter method) in the longitudinal direction (MD direction) is more preferably 1200 mN / 100 mm or less, even more preferably 1000 mN / 100 mm or less, and even more preferably 900 mN / 100 mm or less. The rigidity is a value measured in accordance with the handle ohm meter method of JIS L1913:2010. 【0031】 (Heat seal strength) In the present invention, it is preferable that the anti-adhesion layer located on the outermost surface of the coated paper has heat-sealing properties. When the anti-adhesion layer has heat-sealing properties, it is preferable that the substrate is damaged when the anti-adhesion layers are heat-bonded to each other and then peeled off. The coated paper of the present invention preferably has a heat seal strength of 0.5 N / 15 mm or more in the MD direction at 120°C, more preferably 1.0 N / 15 mm or more, even more preferably 1.5 N / 15 mm or more, even more preferably 2.0 N / 15 mm or more, even more preferably 2.5 N / 15 mm or more, and even more preferably 3.0 N / 15 mm or more. Furthermore, the heat seal strength in the CD direction at 120°C is preferably 0.5 N / 15 mm or more, more preferably 1.0 N / 15 mm or more, even more preferably 1.5 N / 15 mm or more, even more preferably 2.0 N / 15 mm or more, and even more preferably 2.5 N / 15 mm or more. 【0032】 The coated paper of the present invention preferably has a heat seal strength of 1.0 N / 15 mm or more in the MD direction at 160°C, more preferably 1.5 N / 15 mm or more, even more preferably 2.0 N / 15 mm or more, even more preferably 2.5 N / 15 mm or more, and even more preferably 3.0 N / 15 mm or more. Furthermore, the heat seal strength in the CD direction at 160°C is preferably 0.5 N / 15 mm or more, more preferably 1.0 N / 15 mm or more, even more preferably 1.5 N / 15 mm or more, even more preferably 2.0 N / 15 mm or more, and even more preferably 2.5 N / 15 mm or more. [Examples] 【0033】 (Evaluation method) • Filtration rate (Schopper Leaguer) The pulp was measured in accordance with JIS P8121-1:2012. ·Basic weight Measurements for paper substrates and coated paper were performed in accordance with JIS P8124:2011. ·Paper thickness Measurements for paper substrates and coated paper were performed in accordance with JIS P8118:1998. ·density For paper substrates and coated paper, the calculations were based on measured basis weight and paper thickness. 【0034】 ·Smoothness (Ouken style) The coated and uncoated surfaces of paper substrates and coated paper were measured in accordance with JIS P8155:2010 using a water column type Ouken air permeability and smoothness tester (manufactured by Asahi Seiko Co., Ltd.). ·Air permeability resistance (Ouken style) For paper substrates and coated paper, the average value of four measurements was calculated in accordance with the Oguri-type testing machine method described in JIS P8117 (2009) for air permeability and air permeability resistance, and this was defined as air permeability resistance (Oguri-type) (seconds). The measurement range for air permeability resistance using the water column type Oguri-type air permeability and smoothness tester (KY5 model, manufactured by Asahi Seiko Co., Ltd.) is 0 to 5,000 seconds. 【0035】 • Tensile strength Measurements for paper substrates and coated paper were performed in accordance with JIS P8113:2006. • Tear strength For coated paper, measurements were taken in accordance with JIS P8116:2022. ·Moisture permeability For coated paper, measurements were taken in accordance with JIS Z0208:1976 "Test method for moisture permeability of moisture-proof packaging materials (cup method)" under condition B (temperature 40±0.5℃, relative humidity 90%±2%). The measurement involved setting the weight after 16 hours in an environmental testing machine as the initial value, then measuring the weight again after 2 hours, and converting the change to a 24-hour value to determine the moisture permeability. 【0036】 • Water repellency The coated surface (surface of the anti-adhesion layer) was measured in accordance with JAPAN TAPPI Paper and Pulp Test Method No. 68, "Paper and Paperboard - Water Repellency Test Method". ·Water contact angle 4.0 μl of pure water was dropped onto the coated surface (the surface of the anti-adhesion layer), and the dynamic contact angle 10 seconds after dropping was measured using a contact angle measuring device (DAT1100, manufactured by FIBRO System). • Static friction coefficient, kinetic friction coefficient The static and dynamic friction coefficients of the coated surface (anti-adhesion layer surface) in the MD direction were measured using the horizontal method in accordance with JIS P8147. 【0037】 • Heat seal strength The test was conducted in accordance with JIS Z1707:2019 7.4 "Heat seal strength test". Two 100mm square test pieces were cut from the obtained coated paper, and the anti-adhesion layers were brought into contact with each other. Using a heat seal tester (Tester Industries Co., Ltd., TP-7018, seal width 10mm), the pieces were heat-sealed at pressurized temperatures of 120°C and 160°C, with a pressurized pressure of 98kPa and a pressurized time of 1.0 second. Measurement samples were then cut from the heat-sealed 100mm square test pieces so that the long side was 100mm and the short side was 15mm. The sample was left at 23°C and 50% RH for 10 minutes. Under this atmosphere, the long end of the sample was clamped in the upper and lower fixtures of a Tensilon universal tester (A&D Co., Ltd., RTG-1210), and the peel strength, i.e., the HS strength (N / 15mm), was measured while peeling the sample from the long end side at a speed of 300 mm / min (T-type). Heat seal strength was measured under two conditions: when the longer side was oriented in the MD (paper direction) and when the longer side was oriented in the CD (paper width) direction. 【0038】 • Evaluation of cutting properties A test specimen with a width (CD direction) of 50 mm was prepared. This specimen was suspended by gripping its upper end and attaching a 300 g weight to its lower end. A cutting test was performed on n=10 specimens by horizontally pressing the cutter blade (mountain-shaped blade press-cut type) of a packaging machine against it, and the results were evaluated according to the following criteria. (Evaluation Criteria) ○: I was able to cut it all. △: Cannot be cut. 1-2 pieces. ×: Cannot be cut. 3 or more pieces. 【0039】 • Evaluation of rice adhesion Two pieces of coated paper, each measuring 50 x 50 mm, were prepared. 10 g of freshly cooked rice was placed in the center of the uncoated side of one piece of paper, then spread evenly across the entire surface. This was then sandwiched between the coated side (the surface of the anti-adhesion layer) of the other piece of paper, and two microscope slides (approximately 12.5 g) were placed on top without overlapping. After one hour, the top layer of coated paper was removed, and the adhesion of the rice to the anti-adhesion layer was checked and evaluated according to the following criteria. (Evaluation Criteria) ○: Not a single grain of rice is stuck together. ×: There is more than one grain of rice stuck together. 【0040】 • Evaluation using a horizontal pillow bag making machine A test was conducted using a horizontal pillow packaging machine (Suzuki Seisakusho Co., Ltd. SP-803N) to package resin plates (65mm x 55mm). Using a roll of coated paper with a width of 150mm, the vertical sealing temperature was 160°C and the horizontal sealing temperature was 135°C. Thirty plates were continuously packaged so that the finished pillows were 60mm wide and 105mm long, and evaluated according to the following criteria. (Evaluation Criteria) ○: No tears, no peeling of stickers. △: No tears, but some stickers are peeling off. ×: Torn. 【0041】 • Tape peel strength A single-sided adhesive tape (3M Scotch® Removable Tape 811) was applied to the coated surface of coated paper parallel to the MD direction, and a 250g weight (70 x 19 x 24 mm, SUS) was slid across it at a speed of approximately 8 cm per 30 seconds to press it down. A sample was cut to the width of the tape, and the end was peeled off to create the sandwiched portion. The peeling section was clamped in the upper and lower fixtures of the Tensilon universal testing machine (A&D Company, Limited, RTG-1210), and the sample was peeled off (T-type) at a speed of 300 mm / min while measuring the peel strength, i.e., the tape peel strength (N / 18 mm). 【0042】 As paper substrates for coating, the paper substrates shown in Examples 1 to 4 and the paper substrate shown in Comparative Example 1 were prepared, and their paper quality and cutability in a bag-making machine were evaluated. <Creation of paper substrates 1-5> (Example 1) Softwood kraft pulp (NBKP) and hardwood kraft pulp (LBKP) are mixed in a ratio of 65% / 35% by weight and beaten using the Schöpper-Leighler method to achieve a filtration rate of 74°SR. This mixture is then used as papermaking material, produced on a long-wire paper machine, dried in a dryer, and calendered to a yield of 30.1 g / m². 2 A paper substrate 1 was obtained. 【0043】 (Example 2) 100% by weight of softwood kraft pulp (NBKP) is beaten using the Schöpper-Leighler method to achieve a filtration degree of 89°SR as the papermaking raw material. Paper is then made using a long-rod papermaking machine, followed by a drying process in a dryer, resulting in a paper weight of 19.4 g / m². 2 A paper substrate 2 was obtained. (Example 3) Softwood kraft pulp (NBKP) and hardwood kraft pulp (LBKP) are mixed in a 50% / 50% ratio and beaten using the Schöpper-Leighler method to achieve a filtration rate of 85°SR. This mixture is then used as papermaking material, which is produced on a long-wire paper machine and dried in a dryer to produce a paper weight of 21 g / m². 2 A paper substrate 3 was obtained. (Example 4) 100% by weight of softwood kraft pulp (NBKP) is beaten using the Schöpper-Leighler method to achieve a water filtration degree of 60°SR as the papermaking raw material. 7.0% by weight of a wet strength agent (relative to the pulp's form) is added, and the paper is made using a long-wire paper machine. After a drying process in a dryer, calendering is performed, resulting in a paper weight of 33.7 g / m². 2 A paper substrate 4 was obtained. 【0044】 (Comparative Example 1) 100% by weight of softwood kraft pulp (NBKP) is beaten using the Schöpper-Leighler method to achieve a filtration degree of 17°SR as the papermaking raw material. Paper is then made using a long-wire paper machine, followed by a drying process in a dryer, and then calendered to produce paper weighing 37.4 g / m². 2 A paper substrate 5 was obtained. 【0045】 Table 1 shows the paper quality and cutability during bag making for the above paper substrates 1 to 5. [Table 1] 【0046】 ·result Paper substrates with a pulp Shopper Leaguer filtration rate of 50°SR to 90°SR exhibited excellent cutability. 【0047】 Next, the paper substrates 1 to 4 obtained in Examples 1 to 4, which had good cutability, were coated by hand using a Meyer bar with a coating solution containing a styrene-acrylic resin (Brightone FC641V, manufactured by Sakata Inx Co., Ltd.) with a water repellency of R10, as described in Examples 5 to 8 below, to obtain coated paper samples 1 to 4. Similarly, the paper substrates 1 to 4 obtained in Examples 1 to 4 were coated by hand using a Meyer bar with a coating solution containing a polyolefin resin with a water repellency of R6 (Zychsen AC, manufactured by Sumitomo Seika Co., Ltd.), as described in Comparative Examples 2 to 5 below, to obtain coated paper samples 5 to 8. Tables 2 and 3 show the paper quality and evaluation of coated paper samples 1-4 and 5-8, respectively. 【0048】 [Table 2] 【0049】 [Table 3] 【0050】 ·result The coated paper obtained in Examples 5 to 8 had an anti-adhesion layer with a static friction coefficient of 0.3 or less and a water contact angle (10 seconds) of 85° or more, which prevented rice from sticking to it. In contrast, the coated paper obtained in Comparative Examples 2-5 had an anti-adhesion layer with a static friction coefficient of 0.41-0.64 and a water contact angle (10 seconds) of 69.3-72.4°, and rice adhered to it. 【0051】 (Examples 9-10) Using the paper substrate and resin from Example 8, bar coating was performed on one side using an actual machine to obtain coated paper samples 9-10, resulting in different coating amounts (dry weight). The paper quality is shown in Table 4. The obtained coated paper samples were subjected to a horizontal pillow packaging test (SP-803N, manufactured by Suzuki Seisakusho Co., Ltd.). Table 4 shows the evaluation. 【0052】 [Table 4] 【0053】 ·result The coated paper obtained in Examples 9 and 10 of the present invention exhibits excellent bag-making processability and has been confirmed to be suitable for industrial packaging applications such as food products.

Claims

[Claim 1] A paper substrate and an anti-adhesion layer on at least one of its outermost surfaces, The shopper-liger filtration rate of the pulp constituting the paper substrate is 50°SR or more and 90°SR or less. The proportion of softwood kraft pulp to total pulp is 40% by weight or more. The coating amount (dry weight) per side of the aforementioned anti-adhesion layer is 3 g / m². ２ That's all. The coated paper is characterized in that the anti-adhesion layer has a static friction coefficient of 0.3 or less and a water contact angle (10 seconds) of 85° or more. [Claim 2] The basis weight of the aforementioned paper substrate is 60 g / m². ２ The coated paper according to claim 1, characterized in that it is as follows. [Claim 3] The moisture permeability of the coated paper is 150 g / m². ２ The coated paper according to claim 1, characterized in that it is less than or equal to / day. [Claim 4] The coated paper according to claim 1, characterized in that the longitudinal tensile strength is 1.4 kN / m or more. [Claim 5] The coated paper according to claim 1, characterized in that the rigidity in the vertical direction (handle meter method) is 1500 mN / 100 mm or less. [Claim 6] The coated paper is as described in any one of claims 1 to 5, Packaging paper characterized by being suitable for packaging rice, bread, Japanese sweets, Western sweets, or fried foods.

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