JPH11323797A - Non-blotting opaque laminated paper having smooth surface and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide paper having excellent resolution, causing practically no blotting trouble and easily recyclable to pulp after use and provide its production process. SOLUTION: This invention relates to paper having smooth surface and practically non-blotting property and composed of a multi-layer laminated material and its production process. The paper is composed of a substrate layer made of wood pulp paper or non-wood pulp paper and a surface layer produced by using a pulp of a gramineous plant as a main raw material, sufficiently beating the material in the presence of water to obtain a viscous material, subjecting to internal sizing treatment to form a perfect stuff, dispersing in water and making a wet paper on a screen.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to paper and a method for producing paper.

[0002]

2. Description of the Related Art Paper having a smooth surface is considered suitable for precision printing, and recently, new applications have been expanding as precision embossed paper for computers, color copy paper by ink jet, and base paper for pressure-bonded paper. The paper obtained by the normal manufacturing method has a rough surface, so the coated paper is a paper whose surface has been smoothened by applying a process such as coating the surface of a normal paper or laminating a synthetic resin. , Has been used as processed paper. For this reason, extra costs are required for production compared to ordinary paper.In addition, when coated and processed paper is used, the process of collecting and recycling it as used paper, and the processing of waste generated as a by-product can be performed on ordinary used paper. It has been a drawback that it is not easy compared to reproduction. Earlier, the inventor used wood or non-wood pulp as a support layer, using pulp manufactured from grass plants, applying a light size,
We have invented a multi-layer paper having a smooth surface without any size. This multilayer paper has made it possible to perform excellent printing and launch with excellent color reproducibility using an ink jet printer. However, it has been found that this paper has room for further improvement, such as fine thickening of bleeding lines, because ink and ink are good when particularly high resolution is required.

[0003]

The opaque laminated paper having a smooth surface is required to be coated paper and ink-jet paper, and has excellent resolution, does not bleed in practical use, and is used as recycled paper after use. The paper is said to be paper that can be easily recycled as pulp even after it has been manufactured, with a simple process and with conventional equipment. It is an object of the present invention to provide such a paper and a method for producing the same.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention. That is, according to the present invention, (1) a pulp made from a stem stem of a grass plant, such as rice straw, bagasse (squeezed cake of sugar cane), and a pulp made from corn hulls, is used as a main material, and water is added thereto. The mixture is beaten sufficiently to give a complete stock by treating the inner surface size, and then water is added and dispersed to make a wet paper on a wire to form a surface layer. (2) Non-wood pulp such as softwood and hardwood wood pulp or bagasse pulp, abaca pulp, hemp pulp, etc. is beaten by a conventional method, and the size and filler are added as appropriate to prepare a complete paper stock, and the paper is made into a normal thickness wet paper. This is used as a support layer. (3) The wet paper of the surface layer and the support layer is overlapped, and the obtained two-layer wet paper is pressed to squeeze water, and the wet paper is adhered to a mirror-finished dryer by chrome plating or the like so that the surface layer adheres. Place and heat and dry to form a two-layer paper with a smooth surface and a new type of paper. (3 ') When making paper, the upper and lower layers are made into pulp paper, and between these two layers, a support layer is used as a support layer. A layered or multi-layered pulp paper is formed and combined into a single sheet to form a smooth multi-layered laminate on both sides, and if necessary, the surface size is adjusted. Provide a way. This opaque laminate with a smooth surface can withstand precision printing like coated paper, and because it is not coated, it is a new type of precision printing paper that can well withstand intaglio printing required for banknote or securities production. It is. The opaque laminate having a smooth surface absorbs ink in color ink jet printing, but practically does not blur and provides a clear image. Further, the opaque laminate having a smooth surface has a smooth surface and is positioned as a base paper for pressure-bonded paper, so that precise and beautiful printing can be performed. Since it is not coated or laminated with plastic or the like, it can be easily recycled as pulp even if it is once used paper.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram illustrating the configuration of an opaque laminate having a smooth surface according to the present invention. In FIG. 1, 1 indicates a surface layer, and 2 indicates a support layer. In FIG. 2, 1 indicates an upper layer, 2 indicates a lower layer, and 3 indicates a support layer. The surface layer or the upper and lower layers are made of pulp paper mainly composed of pulp of stems of grasses. On the other hand, the support layer is a pulp paper mainly composed of pulp of wood or non-wood plant. In order to obtain a pulp paper constituting a surface layer or an upper layer and a lower layer, a stem of a gramineous plant is used as a raw material, which is pulped and paper-made. When using rice straw, wheat straw, or the like, it is desirable to separate and remove the leaf portion in order to improve the strength of the obtained pulp and improve the drainage of the pulp. The residual rate of leaves or medulla after removal is 30% or less, preferably 10% or less. Prior to wind screening of rice straw, wheat straw, etc., it is easy to cut the straw to 20 cm or less, preferably 3 to 10 cm beforehand, and the leaves are separated and removed from the stem to less than 10%. It is effective for The thick skin of the cane of sugar cane is obtained by crushing the stem of cane sugar (cane), squeezing it, and separating the juice from bagasse (pulverized cake) to separate pis (internodal parenchymal tissue). It can be obtained by removing the stem of sugar cane vertically, and separating and removing the pis containing juice. In this case, a small amount of pis may be mixed in the obtained kein lining, but removing the pis improves the drainage of the obtained pulp and helps to improve the strength of the pulp paper by beating. . The amount of pis mixed is 1 on a dry weight basis.
The content should be 0% by weight or less, preferably 3% by weight or less. In the present invention, kineinide mixed with 0.5 to 5% by weight of pis and sweet sorghum and corn stem bark (lined) obtained by the same treatment can be advantageously used as a pulp raw material. As the pulping method of the straw and the lined, various conventionally known chemical pulping methods using an alkaline cooking liquor such as a soda method, a kraft method, and a PA method (hydrogen peroxide-alkali method) can be used. The use of the PA method is particularly preferred. As the cooking liquor of this PA method, hydrogen peroxide and alkali (Na
OH, NaHCO ₃ , Na ₂ CO ₃ , KOH, K ₂ HC
This is a method using an alkaline aqueous solution containing O ₃ and K ₂ CO ₃ ). According to this PA method, unbleached pulp having good bleaching property, large pentosan content, good beating properties and high strength and high whiteness can be obtained. The monofilaments of pulp made from stems such as straw, cane ind, etc. of these grasses have large inner holes, and after beating at the time of papermaking, almost all cellulose fibers are passed through the wire part, press part and dry part. Since they adhere to each other in a flat state without fibrillation, a pulp paper having a smooth surface and a high density and strength can be provided. Further, the surface can be highly smoothed by calendering. The straw or canned pulp obtained as described above can be bleached to bleached pulp (bleached pulp), if necessary. The pulp bleached to high whiteness no longer has hydrophobic lignin remaining, which makes the beating operation easier. The standard of beating in this case is C.I. S. F. 1
It is 00 to 600 ml, preferably 250 to 450 ml. As the pulp (wet pulp) of the grasses to be subjected to the beating treatment, preferably 70% or more of the main component thereof,
More preferably, 80% or more is adjusted to be in a range of 100 mesh-on in a 20-mesh pass, preferably 80 mesh-on in a 40-mesh pass in a sieving test. In general, a pulp having a preferable sieving section can be obtained by simply performing PA digestion after separating and removing leaves or pis in advance, but a pulp having a more preferable sharp section can be obtained by further sieving treatment. Pulp consisting of such a sharp section makes it possible to increase the strength of pulp paper without drastically reducing the drainage even if the beating process is advanced, giving clear printing, especially paper that can withstand intaglio printing, fax and computer Various images can be excellently launched by inkjet. The opaque laminate having a smooth surface made of the composite material thus obtained enables production and supply of printing paper and inkjet paper having a high degree of functionality. According to the study of the present inventor, this pulp for paper stock is subjected to appropriate sizing, so that it has appropriate water resistance, has water absorbency, and does not cause practical bleeding while sucking black ink or ink. It was confirmed that paper was given. The size in this case includes the inner surface size and the surface size. In the case of the inner surface size, there are alkyl ketene dimer, alkenyl succinic anhydride, neutral size using isocyanate aziridine derivative and the like, and acid size using rosin sizing agent and the like. Cellulose constituting the multilayer paper gradually degrades and loses its strength over a long period of time, but the multilayer paper obtained with a neutral size can withstand extremely long-term storage. The amount of the sizing agent used is 0 to 2.0% by weight, preferably 0.3 to 1.0% by weight, based on the pulp. The surface size is determined by applying on-machine sizing agents such as glue, starch, carboxymethylcellulose (CMC), polyvinyl alcohol, alkyl ketene dimer, styrene maleic anhydride polymer, etc. to the surface of the paper-dried laminate. It is implemented by doing. The amount used is 2% by weight based on the pulp.
Hereinafter, it is preferably 0 to 1% by weight. A complete stock is prepared by adding a stock component to the beaten pulp to which the internal surface sizing agent has been added. In this case, the straw pulp and the lined pulp can be mixed with each other, but it is preferable that the pulp is obtained by the PA method. The proportion of the pulp of the gramineous plant in the total pulp is 60% by weight or more, preferably 80 to 100% by weight, based on the absolute dry weight. The complete stock can include a filler, if necessary, in addition to the pulp. Such fillers include China clay, titanium white, talc and the like. When performing neutral size, sedimentable calcium carbonate can be used. The complete stock containing the lined pulp is formed into a surface layer or a lower layer wet paper in a wire part of a paper machine, and is similarly dewatered and pressed together with a wet paper of a support formed in a press part. The pulp paper is formed into a sheet of laminated paper and then dried in a dry part to form an opaque laminate having a smooth surface. Various types of conventionally known wet paper formation for pulp paper, for example, fourdrinier, short netting, round netting, Yankee paper and twin wire paper machine, etc. Circular mesh part,
A twin wire part or the like is used. The raw material concentration of the complete stock supplied to the wire part is 0.05 to 0.6% by weight, preferably 0.1 to 0.2% by weight.
When obtaining the upper or lower pulp paper as described above,
The thickness of the pulp paper is adjusted to give a basis weight of 5 to 30 g / m ² , preferably 10 to 20 g / m ² .
The thickness of the pulp paper can be adjusted by the raw material concentration, liquid volume, and / or speed of the complete stock supplied to the paper machine. The pulp paper forming the upper layer or the lower layer obtained as described above is prepared with a support and laminated and adhered thereto to form an opaque laminate having a smooth surface. As the pulp paper of the laminated body serving as the support, coniferous or hardwood pulp can be used as a raw material. In addition, when mainly composed of short-fiber pulp made of non-wood such as a plant of the grass family, the tear strength, the tensile strength, the burst strength, and the like can be increased by blending the non-wood long-fiber pulp as desired. Opaque laminated paper with 100% non-wood pulp and a smooth surface that does not bleed, and its manufacture. As non-wood long fiber pulp, jute, kenaf and other bast pulp, abaca, banana, sisal and other leaf fiber pulp, etc.
Seed pulp includes cotton pulp and the like. One or more of these pulp are selected and beaten. In the case of two or more kinds, they are mixed and beaten, or when the difficulty of beating each pulp is severe, they are beaten simply and then mixed. Beating is C. S.
F. 250-650 ml, preferably 450-600
Beating lightly on the order of ml is more suitable for obtaining a final product having a high strength of paper, particularly a high tear strength, since the fibers remain without being cut. A filler may be appropriately mixed into the support to increase the opacity and whiteness of the paper. Fillers include China clay, titanium white, talc and the like. When performing neutral size, it is also possible to use precipitated calcium carbonate. The complete stock obtained by the above operation is formed into a wet paper of a support layer by a wire part of a paper machine, sent to a press part together with the wet paper of the pulp paper described above, and dewatered and pressed to form a sheet of paper. As described above, the adhesive is adhered to a dry part and then dried in a dry part to form a opaque laminate having a smooth surface for Japanese paper-like ink jet printing. Will be described. Various types of conventionally known wet paper webs are formed on the support, for example, fourdrinier, short net, circular net, Yankee paper, twin wire paper, and the like. A net portion, a twin wire portion, or the like is used. The underwater concentration of all stock components of the complete stock supplied to the wire part is
The content is 0.1 to 1.0% by weight, preferably 0.2 to 0.5%. The dry part in the manufacturing process of the opaque laminate having a smooth surface according to the present invention finishes the surface of the dryer to a mirror surface, adheres the mirror surface to wet paper to dry the paper, and finishes the paper surface to a smooth surface as desired. Further, if the surface is super-calendered, a smooth surface is formed so as to have gloss. When a lined pulp paper is formed on one side of the support layer and used for ink jetting, a minimum of one Yankee dryer is sufficient. When the lower layer and the upper layer are made smooth and both sides are used for punching, it is sufficient to use a double Yankee. Furthermore, in the case of mass production with one unit, it is possible to use any surface of the multi-cylinder dryer after processing it into a mirror surface.

[0006]

Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. The percentages described below are percentages by weight.

Example 1 An opaque laminate having two layers and having a smooth surface for single-sided recording and stamping was formed from 100% non-wood pal. The upper layer is 150 kg of rice straw bleached PAP, 7.5 kg of keyed ind (sugar cane thick skin) bleached PAP, and corn bleached bleached P
7.5 kg of AP was placed in a beater, and water was added to adjust the raw material concentration to 3.5%. S. F. Strong viscous beating was performed until it reached 180 m. After beating, a neutral sizing agent alkyl ketene dimer was added as a sizing agent in an amount of 0.8% based on the raw material. In addition, no filler was added at all and the original material concentration was 0.15%
Diluted with water until it becomes wet, and wet paper (17 g / m ² in terms of dry matter, density 0.93 g / cm ³ ) on a circular net
Was formed. The support layer is PAP600 from Keylined.
kg, abaca bleached PAP 150 kg and cotton linter PAP 150 kg were beaten with a beater. S.
F. After beaten to 510 ml, water was added to 50 kg of China clay and 1.5 kg of neutral sizing agent alkyl ketene dimer to make complete stock after the beating. Complete stock is diluted with water by adding water to a concentration of 0.32%.
Wet paper with an original concentration of 19% in a short net (45 g /
m ² density 0.71 g / cm ³ ). For the lower layer, a complete stock was prepared under exactly the same conditions as the upper layer, and a wet paper was formed with a circular net. The support layer and the upper and lower wet paper webs were pressed through a press part without using an adhesive or the like at all between the three layers to squeeze water until the water content reached 51%, thereby forming one wet paper web. The wet paper was dried by heating so that the upper and lower surfaces of the wet paper and the polished surface of the dryer were in close contact with each other, to obtain a laminated paper having a smooth surface. This paper was further subjected to a surface smoothing treatment using a super calender. The resulting paper has a Beck smoothness of 1,500
Second, the whiteness was 84.5%, and the breaking length was 5.3 km in length, 2.4 km in width, and the specific burst strength was 3.7. This paper was printed using a 720-spi color copier capable of copying a picture on the front side and a photograph on the back side, and a clear image was obtained. In addition, a clear image was obtained by color launch of a digital camera. By applying color printing and applying an adhesive, a clear pressure-bonded postcard was obtained.

Example 2 An opaque laminate having three layers and having smooth upper and lower layers was produced. That is, the upper layer and the lower layer have 1 bagasse AP.
The pulp was beaten in the same manner as in Example 1 using 00%, and the raw material was sized using 1.8% of a rosin sizing agent to prepare a complete stock. The upper and lower wet paper webs were respectively extracted with two circular nets. The support layer was made by beating non-wood pulp as in Example 1, preparing wet paper with a Fourdrinier paper machine, dehydrating with a press part without using any adhesive, etc. And dried with a two-tube Yankee dryer with mirror-finished upper and lower surfaces, 350 kg of smooth paper on both surfaces
Created. The resulting paper had a small difference between the front and back sides of the front and back sides with a Bekk smoothness of 1,030 seconds and 975 seconds, respectively. The whiteness was 86.2% and the density was 0.76 g / cm.
³ , the breaking length was 5.5 km, the specific burst strength was 3.8, and the specific tear strength was 109. This paper can be used as it is as inkjet paper for advanced color copying, it can be used as a new security paper by letterpress, intaglio and offset printing, it can be used as a substitute for coated paper, and it can be used as base paper for pressure-bonded paper I knew that.

Example 3 A paper made of a two-layered, single-sided, smooth, opaque laminate was produced using only 100% non-wood pulp. The upper layer was prepared by mixing 80 kg of bleached PAP of canedine and 20 kg of bleached PAP of rice straw, mixed and beaten with a beater, and sized the inner surface using a total of 0.7 kg of alkenyl succinic anhydride and cationic starch. C. S. F. 170 ml of complete stock was prepared.
This was made into a wet paper with a dry basis weight of 15 g / m ² through a circular net.
The supporting layer is 270 kg of bleached PAP of Cained, 27 kg of bleached PAP of abaca, 27 kg of bleached PAP of rice straw, and 27 kg of cotton bleached PAP, each having a CSF of about 4 with a beater.
The mixture was beaten to 50 ml, and a wet web having a dry basis weight of 60 g / m ² was produced with a long net. These are dehydrated in a press part without using any adhesive, etc., and the above two layers are pressed and combined into one wet paper, and the upper layer is closely adhered to a mirror-finished Yankee dryer and dried, and the glue and alum are removed. 0.6k in total
The surface size was determined using g. Further, the paper was subjected to a super calendering treatment to produce an opaque laminate paper made of 100% non-wood pulp having a smooth surface. Surface smoothness is Beck 650
In seconds, the whiteness was 84.5%, the breaking length was 9.6 km in length, 5.1 km in width, the specific burst was 5.1, and the specific tear was 196. A color photograph was launched with a digital camera and a bubble ink jet, and a very good photograph image was obtained.

[0010]

The opaque laminate having a smooth surface according to the present invention can be used regardless of whether it is wood pulp or 100% non-wood pulp as a raw material, and is manufactured by a very simple apparatus and process without coating or processing. it can. The resulting product has a smooth surface and does not bleed in practical use, so it can be used as a base paper for pressure-bonded paper, as a precision security printing paper, as a substitute for coated paper or as a coated paper base paper, and as an inkjet paper for color copiers, color fax machines, and electronic papers. It can now be used for camera and electronic device output.

[Brief description of the drawings]

FIG. 1 is an explanatory configuration diagram of an opaque laminate having a smooth surface according to the present invention.

FIG. 2 is an explanatory configuration diagram of another smooth opaque laminate of the present invention.

[Explanation of symbols]

 In FIG. 1, 1 is a surface layer 2 is a support layer. In FIG. 2, 1 is an upper layer, 2 is a support layer, and 3 is a lower layer.

Claims (9)

[Claims] 1. An opaque support layer mainly composed of wood or non-wood pulp, and a surface layer formed on at least one surface of the opaque support layer. An opaque laminated paper having a smooth and non-bleeding surface, which is a pulp paper as a main raw material and is subjected to combination with an opaque support layer and sizing. 2. The opaque laminated paper according to claim 1, wherein said pulp paper does not bleed due to inner surface sizing. 3. The opaque laminated paper according to claim 1, wherein the surface layer of said pulp paper does not bleed due to surface sizing treatment. 4. A pulp paper having a surface layer having a basis weight of 5 to 30.
opaque laminated paper bleeding during surface smoothness of claims 1, 2 and 3 is g / m ^2. 5. The opaque laminated paper according to claim 1, wherein the surface of said pulp paper is treated with a calender. 6. The surface smoothness according to claim 1, wherein said pulp paper is a pulp paper mainly composed of pulp obtained by digesting a grass plant by an alkali hydrogen peroxide method. Opaque laminated paper that does not bleed. 7. The opaque laminated paper according to claim 1, 2, 3, 4, 5 or 6, wherein all of the pulp using both the surface layer and the support layer is a non-wood pulp. 8. The pulp paper forming the surface layer has a Beck smoothness of 100 seconds or more.
Opaque laminated paper with a smooth and non-bleeding surface. 9. A method for producing an opaque laminated paper comprising a support layer mainly composed of wood or non-wood pulp and a surface layer composed of pulp paper of grasses formed on at least one surface thereof. In at least one side of the support layer, laminating wet pulp paper mainly composed of pulp of grasses, after removing the moisture contained therein by compression, drying on a drying drum The method for producing an opaque laminated paper according to any one of claims 1, 2, 3, 4, 5, 6, 7, and 8, wherein the opaque laminated paper does not bleed.