JPH11198313A - Manufacture of biaxially stretching polypropylene synthetic paper having high glossiness and printing quick drying property - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the surface, printing glossiness and ink quick drying properties of a paper by a method wherein a base material having a three-layered structure formed by extruding two different polypropylene resin materials through one main extruder and two sub-extruders and, after being met, extruding through one T-die head and finally a surface coating is applied to the base material. SOLUTION: A highly crystalline polypropylene and an antistat are extruded through a main extruder 1 and a polypropylene and an anti-blocking agent are extruded through two sub-extruders 1 and, after being joined, extruded through a T-die head so as to form a sheet-like base material having a three-layered structure. After being coolingly formed with a cooling forming device 2, this resultant base material is biaxially stretched with a lengthwise and a widthwise stretching devices 3 and 4. Next, after being cold molded in a cold molding device 2, this base material is biaxially stretched with a lengthwise and a widthwise stretching devices 3 and 4. Next, after a high frequency corona treatment is applied to the base material with a corona treating device 5, the base material is turned into one with the predetermined thickness with a take-up 6. An under and a top coatings are executed with the predetermined coating material. Finally, after a press smoothing treatment is carried out with a press smoothing device, by winding the resultant base material with a winding machine a synthetic paper is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biaxially stretched polypropylene synthetic paper (BO) having a kind of high gloss and printing speed.
PP; Biaxially oriented pol
ypropylene synthetic paper
More specifically, regarding the production method of r), two different polypropylene (PP) resin materials are extruded by one main extruder and two sub-extruders, and they are combined and extruded by one T-die head. After cooling and biaxially stretching after forming a base material with a layer structure, after surface coating including undercoating and top coating,
Wind up and calender it to the required thickness BOPP
And a method for producing the same.

[0002]

2. Description of the Related Art At present, paper made of natural pulp is replaced by polyolefin synthetic paper. This polyolefin synthetic paper has a biaxially stretched polypropylene film as a base layer (intermediate layer) and has an inorganic surface on its surface. Films formed by uniaxially stretching fine powdered polypropylene to form a paper surface layer and pasting them together have already been applied for patents (JP-B-46-40794, JP-A-56-141339, and JP-A-56-13939). No. 118437) and has been put to practical use. Further, in order to improve the intaglio printing property, an aqueous solution of an acrylic acid polymer and polyethylene imine (polyethylenemine) is further applied on the surface thereof (the applied amount is 0.005 to 0.1 g / m ² ),
There is also provided a method of using after drying (Japanese Patent Laid-Open No.
0-10624, JP-A-50-161478). Japanese Patent Application Laid-Open No. 3-87255 discloses a biaxial mixture of 35 to 95% by weight of highly crystalline polypropylene having an isotacticity of 98% and 65 to 5% by weight of either talc or mica powder or a mixture thereof. A film formed by stretching is used as a base material layer (intermediate layer). Separately, at least one surface of the base material layer contains 20 to 90% by weight of highly crystalline polypropylene having an isotacticity of 98% and 80 to 10% by weight of an inorganic fine powder. A film formed by uniaxially stretching a resin mixed with is bonded to form a paper layer, and finally a multilayer resin synthetic paper having an opacity of 90% or more is formed.

The synthetic papers obtained according to the above cited references are excellent in rigidity, mechanical strength and adhesion of the print head, but are not ideal in terms of the ink drying speed in the printing process. Is considered to be the cause of the lack of widespread use, and the amount of fine pores and the degree of connection of the pores on the synthetic paper surface are much less ideal than natural paper, so that after printing, it takes a considerable amount of time for the ink to dry. (Approximately 8
The amount of deposition was also limited in order to prevent the lower synthetic paper from transferring to the back of the upper synthetic paper by stacking. Also, when performing two-sided four-color printing,
Naturally, the number of workers in the printing factory had to be increased, and a work space for waiting for drying had to be secured. In addition, the paper surface is made of a polypropylene uniaxially stretched film containing inorganic fine powder, but the amount of ink adhesion is not as high as that of natural paper, and the desired color saturation is achieved by increasing the amount of ink released from the printing press. I was At the same time, to prevent paper deformation and dimensional change due to the intrusion of the solvent in the ink,
Normally, printing is performed using synthetic paper-dedicated ink that is three to four times as expensive as natural paper printing ink. As can be understood from the above description, synthetic paper having a paper surface structure of a polypropylene uniaxially stretched film containing inorganic fine powder is inferior to natural paper in the printing process and the cost of the entire printing, and this type is Is a reason why natural paper products are not widely used in place of natural paper products.

[0004] Nisshinbo Industries, Ltd. of Japan provides a synthetic paper in which a stretched or unstretched film of polypropylene, polyvinyl chloride, or polyester is subjected to a paper surface layer treatment by using a surface treatment method. The paper's quality characteristics (printability and drying properties) are far superior to synthetic paper using a polypropylene uniaxially stretched film containing the aforementioned inorganic fine powder powder as a paper layer. It can be used. However, the synthetic paper actually obtained by this method has a considerably high production cost, and is disadvantageous for commercial use as compared with a synthetic paper in which a polypropylene uniaxially stretched film containing an inorganic fine powder powder is used as a paper surface layer.
In the manufacturing process, a DMF solvent is used as a solvent for the surface treatment agent. The DMF solvent has a considerably high toxicity, and DMF may be hardened during the process.
A large amount of toxic wastewater was generated during the foaming process, and a large investment was required for wastewater treatment equipment for wastewater treatment. If no wastewater treatment equipment was provided, a very large environmental pollution problem was caused. Also, the thickness of the paper layer after being coated by the reverse transfer method in combination with the DMF solvent system is considerably thick (about 30 μ for general products and about 10 to 20 μ for special products), and a coating thickness of 10 μ or less. Thus, good paper surface quality could not be obtained. Due to the above factors, the cost (raw material, equipment) of the coating process increases, and this type of synthetic paper
It has not yet been widely used in place of natural paper, and has been used only in a narrow range that can make use of the characteristics of synthetic paper.

In view of the above-mentioned drawbacks of the synthetic paper of the prior art, in order to provide synthetic paper with a quality that can be widely used instead of natural paper and to reduce the manufacturing cost, the present applicant has already made a kind of paper. And a method for producing synthetic paper. That is, the materials extruded using one main extruder and two sub-extruders are combined to form one T
A sheet composed of three layers combined with a die head, then laminated by laminating a cold-formed, biaxially stretched, corona treated and biaxially stretched polypropylene white opaque resin film according to the required thickness, and then coating the paper surface with a surface treatment machine Thus, a biaxially stretched polypropylene synthetic paper having gloss and printing quick-drying properties was completed.

[0006] The synthetic paper produced by the manufacturing method provided by the applicant of the present invention is very similar to art paper in the amount of fine holes on the paper surface and the degree of skewing of the holes. The print drying property and print quality were almost the same as those of art paper, and although the quality characteristics were superior to those of traditional synthetic paper, the glossiness of the paper surface and the sharpness of the print color were inferior.

Since the surface of art paper is inherently rather rough, it must be pressed several times to make it smooth.

[0008]

However, there is a problem that the paper gloss of the existing synthetic paper cannot increase the print gloss and that the art paper has a large surface loss due to a large thickness loss due to the smoothing process. At present, it cannot be improved (at present, the roughness is most improved and the roughness is 0.8 to 0.9 μ). The Applicant, through repeated testing, combines the improvement of process and raw material distribution to break through the existing technologies, and has a market competitiveness in terms of manufacturing costs over traditional synthetic paper, In terms of surface quality, it is superior to traditional synthetic paper in terms of paper gloss, print gloss, and ink quick-drying. In addition, the product specific gravity, product, paper surface roughness, print analysis (roughness) The lower the value, the better the printing resolution).

[0009]

The invention according to claim 1 comprises 50 to 90% by weight of a highly crystalline polypropylene (MFI: 0.5 to 6) having an isotacticity of 96% or more and an antistatic agent of 0 to 5%. Weight percent from a hopper into a main extruder set at a temperature of 180 to 280 ° C.
0% by weight and 0-10% by weight of titanium dioxide enter the main extruder from the two feeders respectively to extrude the polypropylene resin mixture,
A resin mixture consisting of 9.5% by weight and an antiblocking agent of 0.5 to 5% by weight is extruded from two sub-extruders set at a temperature of 180 to 280 ° C., and the main extruder and the two sub-extruders are extruded. The extruded products are combined by an extruder and extruded by one T-die head to form a three-layered sheet-like substrate, and the substrate is formed by cooling with a cooling roller at 15 to 80 ° C. Biaxially stretching, the biaxial stretching
After pre-heating at ~ 150 ° C and stretching in the longitudinal direction, after annealing, the film is stretched 3 to 7 times in the longitudinal direction. After that, it is further preheated at 130 to 190 ° C, stretched in the horizontal direction, and subjected to the annealing process to be oriented horizontally. The substrate is subjected to high-frequency corona treatment under an efficiency of 20 to 150 kW, and the substrate is wound with a winding machine with a thickness of 200 μm or less. Chlorinated polypropylene resin, 5 to 20% by weight, acrylate resin 0
-5% by weight, calcium carbonate 0-40% by weight, clay powder 0
-40% by weight, titanium dioxide 0-5% by weight, toluene 3
An undercoating material comprising 1 to 50% by weight, an antistatic liquid of 0 to 3% by weight, an ultraviolet absorber of 0.1 to 0.3% by weight, and an antioxidant of 0.1 to 0.3% by weight. 40
Undercoating, which is the first stage paper surface treatment, is performed with a 0 mesh, intaglio printing roller having an intaglio depth of 60 to 10 μm.
-20% by weight, antifoaming agent 0.2-0.5% by weight, calcium carbonate 0-48% by weight, clay clay 0-45% by weight, titanium dioxide 0-5% by weight, water repellent (water re)
0.2 to 0.7% by weight of a stable agent)
Lubricant 0.5-2% by weight, starch 0-6% by weight, aqueous ammonia 0.2-0.8% by weight, fluorescent paint 0.01-0.1
100 to 400 mesh, intaglio depth 60 to 100% by weight with the base material already undercoated with a top coating material consisting of 26% to 30% by weight of pure water.
Using a 10μ intaglio coating roller, the top coating, which is the second stage paper surface treatment, is performed using the intaglio coating roller to obtain a semi-finished product of synthetic paper having a thickness of 200μ or less, and both sides of the semi-finished product are further heated. A press smoothing device consisting of a metal roller and a high-temperature resistant plastic roller, with a temperature of 40 to 200 ° C and a linear pressure of 10 to 500 kg / m.
m, and then wound by a winder to form a synthetic paper having a thickness of 200 μm or less. Manufacturing method.

According to a second aspect of the present invention, there is provided the method for producing a biaxially stretched polypropylene synthetic paper having high glossiness and fast drying property of the first aspect, wherein two rolls of the synthetic paper having a thickness of 200 μm or less are obtained. Place in the coating sending section and laminating sending section of the laminating device, coat the glue on the base material placed in the coating sending section, dry, laminate with the base material placed in the laminating sending section, and thickness After the base material of 200μ or more,
An undercoating, a top coating treatment, and a press smoothing treatment using the same materials, conditions and methods as those used in the method for producing a biaxially oriented polypropylene synthetic paper having high glossiness and printing quick drying according to claim 1 taken up by a winding machine. To obtain a synthetic paper having a thickness of 200 μm or more, and a method for producing a biaxially stretched polypropylene synthetic paper having high glossiness and printing speed-drying property.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The technical contents of the present invention will be described below with respect to the synthetic paper base material provided by the present invention, the composition of the coating material applied to the top and bottom surfaces thereof, and the manufacturing method thereof. Do.

The base material of the biaxially oriented polypropylene white opaque resin of the present invention has a three-layer structure, in which the intermediate layer has a high isotacticity of 96% or more supplied from a hopper by one extruder. A resin mixture comprising 50 to 90% by weight of crystalline polypropylene, 0 to 5% by weight of an antistatic agent and 10 to 40% by weight of calcium carbonate supplied from a side feeder, and 0 to 10% by weight of titanium dioxide is formed by extrusion. The upper layer above the middle layer and the lower layer below the middle layer are made of two sub-extruders, polypropylene 95-99.
A resin mixture consisting of 5% by weight and an antiblocking agent of 0.5 to 5% by weight is formed by extrusion. The materials extruded by the three extruders described above are combined, extruded by one T-die head to form a three-layer sheet, and subjected to biaxial stretching and corona treatment to form the base material. Furthermore, 5 to 20% by weight of a chlorinated polypropylene resin, 0 to 5% by weight of an acrylate resin, and 0 to 40% of calcium carbonate.
Wt%, clay clay powder 0-40 wt%, titanium dioxide 0-5 wt%, UV absorber 0.1-0.3 wt%, toluene 3
An undercoating material containing 1 to 50% by weight, an antistatic solution of 0 to 3% by weight, and an antioxidant of 0.1 to 0.3% by weight is used to coat the bottom surface of the substrate using an intaglio coating roller. . Further, 10 to 20% by weight of an aqueous solution of an acrylate resin, 0.2 to 0.5% by weight of an antifoaming agent, 0 to 48% by weight of calcium carbonate, 0 to 45% by weight of clay powder, 0 to 5% by weight of titanium dioxide, Waterproofing agent (water
0.2 to 0.7% by weight of a resist agent, 0.5 to 2% by weight of a lubricant, 0 to 6% by weight of starch, 0.2 to 0.8% by weight of aqueous ammonia, 0.01 to 0.01% of a fluorescent paint
A top coating material containing 0.1% by weight and 26 to 30% by weight of pure water is used to coat the upper surface of the undercoated substrate using an intaglio coating roller. Further, the press smoothing process is performed on the paper surface by using a press smoothing device composed of a heated metal roller and a high heat resistant plastic roller, and the biaxially oriented polypropylene of the present invention having high gloss and printing quick drying is synthesized. Complete the paper.

In the present invention, high-crystallinity polypropylene is used as a main raw material in order to provide a synthetic paper suitable for general paper applications. The polypropylene resin in the base material used in the present invention has a melt flow index (hereinafter, MFI) of 2 to 6 (230 ° C./2.16 kg ASTM).
D1238), most of which are isotactic and homogeneous polymers. The structure of this kind of polymer is an array in which the molecular chains are arranged. The size and distribution of the molecular weight of this type of raw material affects the mechanical strength and quality uniformity of synthetic paper.

[0014] The calcium carbonate used in the above-mentioned base material does not use a foaming agent, and the specific gravity of the base material is greatly reduced to 0.6 or less. Plays the role of expanding the crevices of the fine pores and imparting good opacity to the substrate. In order to prevent dispersion of the inorganic filler, it is possible to mix the inorganic filler and the polypropylene resin and knead them first to form a master batch. Further, in addition to calcium carbonate, silica, clay, clay, and calcium silicate can be used as the inorganic filler.

The titanium dioxide used for the above-mentioned base material is enamel-type titanium dioxide, which is used to adjust the shielding property of synthetic paper and to enhance the effect of preventing ultraviolet rays.

As the antistatic agent used in the above-mentioned base material, at present, biaxially oriented polypropylene (BOP) is generally used.
Any of the antistatic agents used in P) can be used, of which the tertiary amine eliminates electrostatic effects that can occur during the coating process due to its charge transfer properties.

When the substrate is manufactured, an anti-adhesive agent is separately added to prevent the film surfaces from sticking to each other when the material is wound up, which is currently generally used as an anti-adhesive agent in biaxially oriented polypropylene. Silicon dioxide. In addition, the base material has a three-layer structure, and the upper and lower layers have relatively good roller adhesion when the base material is cooled, and have good plate surface quality. However, it is possible to add inorganic fillers, such as calcium carbonate, titanium dioxide, terra alba, calcium silicate, clay, etc., if they give the substrate better shielding and coating strength. Can be simply a single-layer structure.

The chlorinated polypropylene resin used in the above-mentioned undercoating material has an adhesive ability to a non-polar coated surface, and its degree of salinity is 20 to
40% are used as material.

The acrylic resin used in the above-mentioned paper surface treating agent provides an effect of improving the synthesis and cutting strength of the paper surface, and is also greatly involved in improving the weather resistance. However, it is also possible not to use it in consideration of paper flexibility.

Calcium carbonate and clay used in the above-mentioned undercoating material have an effect of improving the ink drying ability at the time of printing, and the particle size range used is 0.5 to 5%.
μ, and all of diatomaceous earth, calcium silicate, and clay can be used.

The titanium dioxide used in the undercoating material described above is used to give good whiteness and visual texture to the paper surface of the synthetic paper, and also enhances the shielding property of the synthetic paper and has the effect of preventing ultraviolet rays. It is a great help in achieving it.

The antistatic agent used in the above undercoating material is a solvent type antistatic solution, the main component of which is an amide, and its main function is to remove static electricity generated during the printing process. It is to remove.

The outdoor use time of the synthetic paper of the present invention is extended,
In order to prevent aging and decomposition due to the action of ultraviolet rays, an ultraviolet absorber may be added to the undercoating material, and the dose is 0.05 to 0.15% by weight.

In order to prevent the synthetic paper of the present invention from being affected by the strength of the paper surface due to the action of oxygen molecules in the atmosphere,
It is also possible to add an antioxidant to the undercoating material, and any antioxidant used in plastic products can be used as the antioxidant.

The aqueous solution of the acrylate resin used in the top coating material of the present invention is used to bind to calcium carbonate, titanium dichloride, and clay, and the adhesive strength between the aqueous solution and the under coating material is also low. Can not. In terms of usability, the colloid type is usually better than the solution type and the suspension type, and belongs to the synthetic adhesive. In addition to the acrylate resin aqueous solution, if weather resistance is not considered, styrene-butadiene latex (Styrene-ButadieneLat) is used.
ex), butadiene acrylonitrile emulsion (B
utadiene-Acrylonitrile Em
ulsion), polyvinyl acetate (Polybi)
Nyl Acetate), vinylidine chloride polymer (Vinylidine Chloride Po)
lymer), butyl latex (Butyl Lat)
ex) and polyvinyl alcohol and cellulose derivatives.

The starch raw material used in the above-mentioned top coating material is also used as an adhesive, and its high viscosity property after dissolution assists in adjusting the use viscosity of the paint, and can be used for either natural starch or modified starch, which are carbohydrates. Can be used, and they have slight differences in adhesive strength and melt viscosity, but the distribution is adjusted according to the situation.

Calcium carbonate, terra alba, and titanium dioxide used in the above-mentioned top coating material are effective in ink drying property on coated paper, good printability, and physical qualities of paper (whiteness, glossiness, opacity). , Coarseness, etc.), and the ratio of the three components and the particle size are selected according to the required physical properties of the paper surface. Depending on the physical properties of the paper, other types of fillers such as aluminum oxide, silica, barium sulfate, satin white (Sati White)
n white), zinc oxide, calcium sulfate, miscellaneous pigments
Can be used. In addition to the powder filler, a liquid filler (Slurry), for example, a calcium carbonate slurry or a clay slurry may be used.

The antifoaming agent used in the above-mentioned top coating material prevents bubbles from being generated in the top coating material and prevents the bubbles from affecting the quality of the coated paper surface and the coating operation. It has the effect of doing. The formation of bubbles is related to the surface tension of the coating material, the surface viscosity, the degree of agitation, the temperature pH value and the transport conditions of the coating material.

The action of the waterproofing agent in the above-mentioned top coating material is to increase the paper surface strength, to prevent the action of water molecules from causing abnormalities during printing, and to improve ink receptivity.

The lubricant in the above-mentioned top coating material is used to improve the flowability of the paint and to improve the print quality of the paper surface, and includes water-soluble soap, latex emulsion,
Any of resin, amide and insoluble soap can be used.

The aqueous ammonia in the above-mentioned top coating material is used for pH adjustment and provides an effect of increasing the stability of the chemical additive such as the coating material.

The dyeing dye used in the above-mentioned top coating material is added in a very small amount to adjust the hue of the paper surface.

The following will describe the manufacturing process and the apparatus employed in the present invention with reference to the drawings. Please refer to FIG. 1. The extruder device (1) includes one main extruder with two side hoppers and two sub-extruders, the temperature conditions of which are the raw material of the resin mixture, MFI, crystallinity, viscosity, additives Although it is set according to the difference in the production line speed (winding speed), it is usually set to 180 to 280 ° C. The three-layer structure of the synthetic paper base material obtained in the present invention is achieved by a three-layer co-extrusion method.
They are combined by a die head and extruded as one. 2. The cooling molding device (2) is a water-cooling type or an air-cooling type cooling device, performs a cooling pattern for the three-layer coextrudate extruded at a high temperature of 180 to 280 ° C., and controls the cooling temperature in this process. Success depends greatly on the success of the subsequent manufacturing steps. The cooling temperature is usually set between 15 and 80 ° C., and the cooling temperature is adjusted within this range by the thickness of the substrate and the speed of the production line. 3. The longitudinal stretching device (3) receives the substrate after cooling and molding, first preheats the substrate at 120 to 150 ° C (adjusted within this range according to the thickness of the substrate and the speed of the production line) to soften the material plate. Further, one-stage or two-stage stretching at low speed and high speed is performed to enhance the mechanical strength of the base material in the vertical direction, and further, annealing is performed. Usually, the longitudinal stretching ratio is set to 3 to 6 times. 4. The horizontal stretching device (4) first converts the comparatively thinned raw material plate that has been subjected to the vertical stretching process as described above to 150-150.
190 ° C (set according to the thickness of the material plate and the speed of the production line)
Pre-heated to soften, and then stretched sideways,
Finally, annealing is performed, and the base portion is shrunk to increase dimensional stability. Usually the transverse stretching ratio is 5 to 12
Double, which is set according to product characteristic requirements. 5. The corona treatment device (5) improves the surface quality characteristics of the substrate and increases the strength of the substrate surface and the paper surface treating agent. The device employs a high-frequency discharge device with an efficiency of 20
１５０150 Kw (adjusted by the production line speed), and the surface lubrication tension is 36-45 dyne / cm ² . 6. The winding device (6) winds the base material of the present invention, which has been produced and completed as described above, using a single tubular material to form a finished product having a width of 8M. State. 7. The laminating apparatus (FIG. 3) is used when it is desired to obtain a synthetic paper having a thickness of 200 μ or more. Before lamination, each layer is coated. Determined by the viscosity of the primer, the primer used is a polyamide ester or other addition product of polyamide and polyamidoimide, and an acrylate polymer containing quaternary ammonium, which is suitable for lamination on a polypropylene substrate. It is said. In the above-described apparatus, the same or different synthetic paper base material having a thickness of 200 μm or less of two rolls is placed in the coating and laminating delivery section 1′5 ′, respectively, in which the coating and laminating delivery section 1 ′ are placed. The coated substrate is coated with glue in a glue tank 3 'by an intaglio coating roller 2', and the substrate after glue coating is sent to a dryer 4 'and dried at a drying temperature of 30 to 70 ° C. After the solvent is removed and the solvent in the glue is removed,
Is sent to the laminating roller 6 'at ~ 70 ° C, and laminating with another substrate of the same or different thickness which is sent from the laminating sending section 5', which is another sending section, proceeds. After lamination, the winding by the winder 7 'is advanced, and thus the product of the present invention having a thickness of 200 μ or more is completed. 8. The surface treatment apparatus (FIG. 4) performs a paper surface treatment on a base material having a thickness of 200 μ or less produced by the apparatus of FIG. By doing so, a paper surface layer such as natural paper having a large number of fine pores and having an extremely good degree of contact with holes is formed. The apparatus has a total of four sets of intaglio coating rollers, and performs coating on both sides of the substrate in an online manner. In the apparatus, a base material having a thickness of 200 μm or more is placed in a coating sending section 1 ″, and a paper surface treating agent is coated on the surface of the base material by a first intaglio coating roller 2 ″. The substrate after the first paper surface treatment is dried by the drying equipment 3 ″ installed between the first intaglio coating roller and the second intaglio coating roller, and further dried by the second intaglio coating roller 4 ″. Is subjected to a second paper surface process. Finally, the base material after the second paper surface treatment is sent to the lower drying section 5 ″ of the drying equipment having a size of 20M, and is completely dried to completely volatilize the solvent on the paper surface. The paper surface processing of the first surface is completed by the steps of (1) and (2) through the same steps as the paper surface processing of the first surface.
After the surface of the substrate is finished, the third intaglio coating roller 6 ″, the drying equipment 7 ″, the fourth intaglio coating roller 8 ″, and finally the 20M drying equipment in the upper layer drying section 9 ″ The two-sided paper processing proceeds, and finally the winding by the winding machine 10 ″ is completed. This device is a device that performs coating on both sides with two sets of intaglio coating rollers using a double-sided online method. Can be applied to one side or both sides, and one or two, three, or four times the paper surface treatment can be performed on each side.The intaglio depth of the intaglio coating roller is 15 μm to 6 μm.
The mesh size is set to 0μ, and the mesh size is from 100 mesh to 400 mesh. In addition, the intaglio coating roller can be replaced with a lithographic coating roller. 9. The press-smoothing device (5) performs a press-smoothing process on the paper surface of the base material of 200 μm or more, which has been subjected to the coating process by the surface treatment device of FIG. 4, and smoothes the paper surface (low roughness). Glossy (snow white paper can be used by distributing the top coating material on the paper). This apparatus includes a press smoothing apparatus composed of two sets of metal rollers and plastic rollers, and its processing equipment is connected to a surface treatment machine to enable online production. The semi-finished product after the coating is placed in the press smoothing sending section 1a, and the semi-finished product is first subjected to the first press smoothing device 2a in which the first metal roller is combined with the first plastic roller under the first press. A press smoothing process is performed, and subsequently, a second press smoothing process is performed by a second press smoothing device 3a in which the second metal roller is combined with the second plastic roller on the bottom, and the first and second metal rollers are finally combined. The semi-finished product after the press smoothing process is wound by the winder 4a.

In order to further understand the technical contents of the present invention, some embodiments will be described below. The following examples provide synthetic papers for calligraphy, printing, packaging and other uses, but the following examples do not limit the scope of the invention.

[0035]

EXAMPLES Example 1 Double-sided printing quick-drying biaxially oriented polypropylene synthetic paper with a thickness of 200 μ or less, 60% by weight of polypropylene (MFI: 2-3) and 2% by weight of an antistatic agent were mixed by a mixer. 30% by weight of calcium carbonate powder and 8% by weight of titanium dioxide were separately introduced into the main extruder by two side feeders, and 99% by weight of polypropylene and 1% by weight of an antiblocking agent were separately mixed by a mixer. After mixing, the mixture is introduced into two sub-extruders, and the extruder temperature is 180 to 28.
At 0 ° C., extruded with a T-die head in a three-layer co-extrusion system, and cooled and formed with a cooling roller at a temperature of 15 to 80 ° C. into a polypropylene base material. After stretching, the film is stretched 5 times in the machine direction, cooled by annealing after the stretching, and then cooled, and then further introduced into a machine for transverse stretching, at a temperature setting of 150 to 185 ° C.
Pre-heated under a horizontal direction, further stretched in the transverse direction by 9 times, further cooled by annealing after stretching, controlled the shrinkage rate of the base material, and further subjected to corona treatment to the base material that left the transverse stretching device. After the material is coated, it is possible to obtain a good strength of the paper layer. Finally, the material is wound by a winder to obtain a base material having a thickness of 200 μm or less. An example of performing a coating treatment of a total of 8 μm in total thickness of a top coating on the top surface of the paper and an undercoating on the bottom surface of the base material of a 130 μm-thick double-sided printing quick-drying biaxially oriented polypropylene synthetic paper with a surface treatment machine. Described below (using two sets of coating rollers for each side, coating on both sides online). A 130 μm substrate is placed on the coating sending section, and the first intaglio coating roller having a depth of 180 μm and a 25 μ intaglio depth is used for the upper surface thereof. The undercoating of the front surface of the substrate is progressed with an undercoating agent consisting of 3% by weight, 41.7% by weight of toluene, 1% by weight of an antistatic liquid, 0.2% by weight of an ultraviolet absorber and 0.1% by weight of an oxidizing agent. And the drying equipment between roller sets
After drying at 00 to 150 ° C., the second intaglio coating roller having a depth of 150 mesh and an intaglio depth of 35 μm further dried the acrylic ester resin solution (solid content: 40%) 15% by weight, starch 3% by weight, antifoaming agent 0 0.3% by weight, waterproofing agent 0.5% by weight, lubricant 1% by weight, calcium carbonate 10% by weight, clay 40% by weight, titanium dioxide 2% by weight, dye 0.05% by weight, ammonia water 0.5% by weight , Pure water 2
The top coating on the front of the equipment is progressed with a top coating material of 7.65% by weight,
Substrate that has been completely dried at 100-150 ° C with a large drying machine and has already undercoated and top-coated the front surface is used for the third intaglio coating roller of 150 mesh, 35μ intaglio depth, and the first intaglio coating roller After progressing undercoating on the other side of the substrate using the undercoating material
Further, after drying at 100 to 150 ° C. in a drying facility, the substrate is further coated with a fourth intaglio coating roller having a depth of 150 mesh and 35 μ intaglio using the same top coating material used in the second intaglio coating roller. On the other hand, the top coating on the other side is advanced, and thereafter, it is completely dried at 100 to 150 ° C. in a 26M large drying apparatus, and finally wound up by a winder. The semi-finished product after the coating is completed is placed in the sending section of the press smoothing device, and the front and the front are set by two sets of a roller set including a metal roller and a plastic roller set at a temperature of 180 ° C. and a linear pressure of 50 kg / mm. On the other hand, after press smoothing
It is then wound up by a winder and completed. 14
A printing quick-drying biaxially oriented polypropylene synthetic paper having a high gloss on both sides and having a thickness of 0 μm is obtained. The print drying property is extremely good, and the outer layer of the printing layer dries within about 2 minutes,
The print layer is completely dried within minutes and the paper gloss is 70%
As a result, the coarseness is 0.5 μ, and it can be used for various paper applications such as writing, printing, and packaging. The physical properties of the synthetic paper of the present invention are as shown in Table 1.

Example 2: Double-sided printing quick-drying biaxially oriented polypropylene synthetic paper having a thickness of 200 μ or more A double-sided printing quick-drying biaxially oriented polypropylene synthetic paper having a thickness of 280 μ (200 μ or more) was subjected to a laminating machine and surface treatment. An embodiment completed using a machine is as follows. The two rolls of 135μ substrate are placed on the coating and laminating delivery sections respectively (1 ′ in FIG. 3,
5 '). The glue in the glue tank 3 'is coated on the 135 µm thick substrate of the coating sending section 1' using an intaglio coating roller 2 'having a depth of 175 lines and 35µ intaglio. The substrate having a thickness of 135 μm after the glue coating is fed into a dryer 4 ′ having a drying temperature of 70 to 100 ° C. and a length of 10 meters to remove the solvent in the glue. With respect to the base material, the lamination with another 135 μm thick base material sent from the laminating sending unit 5 ′ proceeds at the laminating roller 6 ′ at 40 to 50 ° C., and after laminating. The substrate having a thickness of 170 μm is wound up by a winder and subjected to a paper surface treatment by a surface treatment machine. Further, the under coating and the top coating described in the first embodiment are completed by progressing the material distribution, coating conditions, and press smoothing conditions. Table 1 shows the physical properties of the thus-obtained printing quick-drying biaxially oriented polypropylene synthetic paper having a high glossiness on both sides and having a thickness of 280 μm.

[Table 1]

[0037]

According to the method of the present invention, the inorganic filler is directly supplied to the extruder by using the side feeder alone, and the inorganic filler and the resin according to the well-known technique are first manufactured into a masterbatch and then mixed with the PP resin. The process of feeding the extruder later is eliminated, thereby reducing the number of working steps and reducing manufacturing costs.

In the press smoothing treatment in the method of the present invention, by using a heat softening press smoothing machine that heats and softens a coating material to perform press smoothing as a press smoothing device, good low smoothness and high glossiness are obtained. And low specific gravity requirements. Moreover, the amount of holes on the paper surface obtained and the degree of skewing of the holes are comparable to that of art paper, and the printing speed is superior to that of traditional synthetic paper. The synthetic paper obtained by the method of the present invention has a roughness of 0.5 μ and has a good low-smoothness paper surface, and achieves high print resolution.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a polypropylene synthetic paper manufactured according to the present invention.

FIG. 2 is an apparatus for producing a base material having a thickness of 200 μ or less according to the present invention.

FIG. 3 is a laminating apparatus of the present invention.

FIG. 4 is a surface treatment apparatus of the present invention.

FIG. 5 is a press smoothing apparatus of the present invention.

FIG. 6 is a super press smoothing apparatus of the present invention.

[Explanation of symbols]

 A Foaming layer for lowering density B Adhesive layer of paper surface treatment agent C Coating material layer 1 Extruder device 2 Cooling device 3 Vertical stretching device 4 Horizontal stretching device 5 Corona treatment device 6 Winding device 1 'Coating sending unit 2' Intaglio Coating roller 3 'Glue tank 4' Dryer 5 'Laminating sending section 6' Laminating roller 7 'Winding machine 1 "Coating sending section 2" 1st intaglio coating roller 3 "Roller drying apparatus 4" 2nd intaglio coating Roller 5 "Lower drying section of drying equipment 6" Third intaglio coating roller 7 "Drying equipment between rollers 8" Fifth intaglio coating roller 9 "Upper drying section of drying equipment 10" Winder 1a Press smoothing sending section 2a 1st Press smoothing device 3a Second press smoothing device 4a Press Smoothing winder 1b press smoothing sending part 2b press smoothing device 3b press smoothing winder

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification code FI // C08L 23/12 C08L 23/12 C09D 123/28 C09D 123/28 133/08 133/08 B29K 23:00 105: 16 B29L 9:00

Claims (2)

[Claims] 1. 50 to 90% by weight of a highly crystalline polypropylene (MFI: 0.5 to 6) having an isotacticity of 96% or more and 0 to 5% by weight of an antistatic agent from a hopper to 180 to 2%.
The main extruder is set to a temperature of 80 ° C., and 10 to 40% by weight of calcium carbonate and 0 to 10% by weight of titanium dioxide are respectively input to the main extruder from the two feeders to extrude a polypropylene resin mixture. A resin mixture consisting of 95 to 99.5% by weight and an antiblocking agent of 0.5 to 5% by weight is extruded from two sub-extruders set at a temperature of 180 to 280 ° C. The products extruded by each of the sub-extruders are merged and extruded with one T-die head to form a three-layer sheet-like base material, and the base material is formed by cooling with a cooling roller at 15 to 80 ° C. Thereafter, the film is biaxially stretched. In the biaxial stretching, the film is preheated at 120 to 150 ° C., stretched longitudinally, and then stretched 3 to 7 times in the longitudinal direction by annealing, and then further stretched by 1 to 1. Preheated at from 0 to 190 ° C., and lateral stretching without with a stretching 5 to 12 times sideways by annealing treatment, 20 to the further base material
A high-frequency corona treatment is performed under an efficiency of ~ 150 KW, and a winding machine is used to form a substrate having a winding thickness of 200 µ or less. Separately, 5 to 20% by weight of a chlorinated polypropylene resin, 0 to 5% by weight of an acrylate resin, Calcium carbonate 0-40
0 to 40% by weight of clay powder, 0 to 5% by weight of titanium dioxide, 31 to 50% by weight of toluene, 0 to 3% by weight of antistatic liquid, 0.1 to 0.3% by weight of ultraviolet absorber, oxidation An undercoating material consisting of 0.1 to 0.3% by weight of an inhibitor is used to perform undercoating, which is the first-stage paper surface treatment, with an intaglio coating roller having a mesh of 100 to 400 mesh and an intaglio depth of 60 to 10 μm. 10-20% by weight of acid ester resin aqueous solution, antifoaming agent 0.2-
0.5% by weight, 0 to 48% by weight of calcium carbonate, 0 to 45% by weight of clay powder, 0 to 5% by weight of titanium dioxide, water resistant agent
2 to 0.7% by weight, lubricant 0.5 to 2% by weight, starch 0 to 0%
6% by weight, 0.2-0.8% by weight of ammonia water, 0.01-0.1% by weight of fluorescent paint, 26-30% by weight of pure water The base material is subjected to top coating, which is a second-stage paper surface treatment, using an intaglio coating roller with an intaglio coating roller having an intaglio coating roller of 100 to 400 mesh and an intaglio depth of 60 to 10 μm. A semi-finished product is obtained, and a press smoothing device comprising a heated metal roller and a high temperature resistant plastic roller is further provided on both sides of the semi-finished product at a temperature of 40 to 200 ° C. and a linear pressure of 1
After performing a press smoothing treatment at 0 to 500 Kg / mm, it is further wound by a winder to form a synthetic paper having a thickness of 200 μ or less. A method for producing polypropylene synthetic paper. 2. The method for producing a biaxially oriented polypropylene synthetic paper having a high glossiness and a printing quick drying property according to claim 1,
The obtained two rolls of synthetic paper having a thickness of 200 μ or less are respectively placed on the coating sending section and the laminating sending section of the laminating apparatus, and the base material placed on the coating sending section is coated with glue, dried, and laminated. 2. A biaxially stretched polypropylene composition having high glossiness and printing quick drying according to claim 1, after laminating with a substrate placed in the sending section to form a substrate having a thickness of 200 μ or more, and then winding it with a winding machine. Biaxial stretching with high gloss and printing fast drying, undercoating and topcoating by the same materials, conditions and methods as in the paper manufacturing method, and press-smoothing to obtain a synthetic paper with a thickness of 200μ or more A method for producing polypropylene synthetic paper.