JPH03106476A - Preparation of cast coated paper - Google Patents

Abstract

PURPOSE:To stably and continuously prepare cast coated paper of high quality for a long time by bringing the coating layer provided on base paper into pressure contact with the surface of a heating drum having mirror surface gloss and coated with a fluorine-containing surfactant during a time when the coating layer is in a wet state. CONSTITUTION:A coating layer based on pigment and an adhesive is formed on base paper. During a time when the coating layer is in a wet state, the coating layer is brought into pressure contact with the surface of a heating drum having mirror surface gloss and coated with a fluorine-containing surfactant to be subjected to intensive gloss finish to prepare cast coated paper. As a pref. embodiment of the fluorine-containing surfactant, a compound represented by formula I (wherein Rf is a 4-20C perfluoroalkyl group, n is an integer of 1-3, M is alkali metal, Z is a divalent crosslinking group bonded to the carbon atom of Rf and the oxygen atom of a phosphate group, m is an integer of 0 or 1) is designated.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention provides a method for producing cast coated paper of high quality with high efficiency. ``Prior Art'' Conventionally, methods for manufacturing cast coated paper include the wet casting method (for example, Japanese Patent Publication No. 3407/1983, 38
-25160), a gel casting method in which the wet coating layer is gelled and brought into contact with the heated drum surface for a glossy finish (for example, Japanese Patent Publication No. 3B-15751, 40-72
No. 07, U.S. Patent No. 3,377,192, JP-A-51-40
No. 410), a rewet casting method in which the wet coating layer is once dried or semi-dried, then plasticized by rewetting and pressed against the heated drum surface (for example, U.S. Pat. No. 27598).
No. 47, Special Publication No. 4B-38005, Japanese Patent Publication No. 51-
102111) etc. are known. In all of these methods for producing cast coated paper, a coating layer containing pigments and adhesives as main components is provided on the base paper, and while the coating layer is in a wet state, it is pressed against the surface of a heated drum having a mirror surface. However, they have one thing in common in that they produce a coated paper that is smooth and highly glossy by copying a mirror surface onto the coated layer that is in a plastic state. Therefore, in the production of cast coated paper,
In order to perform continuous and stable operation, it is necessary that the heating drum surface, which has a mirror surface, be faithfully transferred to the paper surface.
To achieve this, it is absolutely necessary that even a part of the coating layer does not remain on the surface of the heating drum when the paper is released from the surface of the heating drum. When using a simple paint consisting of pigments and adhesives and casting on an untreated heated drum, it is difficult for the paper to release from the heated drum after drying, and the coated layer deteriorates immediately after the start of operation. A satisfactory cast finish cannot be achieved due to the so-called drum bick phenomenon in which a portion of the paper adheres to the heating drum, and the paper tends to stick to the heating drum and break. Various proposals have been made to improve the releasability of paper from the heated drum surface.

For example, pre-heated drum surface can be heated with fatty acids, fatty acid soap, etc.
It is treated with oil-based substances such as sulfated mustard oil, tributyl phosphate, xylene, terpene, monochlorobenzene, etc., and furthermore, these oil-based substances are added to the paint used.
A method of adding about 1.0% by weight has been proposed (US Pat. No. 2,568,288, Japanese Patent Publication No. 3407/1983). In this method, an oil film is formed on the surface of the heating drum, and as the coated layer dries and is released from the mold, part of the oil film is carried away. An oil film of constant thickness is formed on the surface of the heated drum to maintain an apparent equilibrium state and aid in paper release.

In addition to the oil-based substances mentioned above, polyethylene, alkyl phosphates, C-JtJM higher fatty acid esters, lecithin, and nonionic activators are used as mold release agents in paints, gelling liquids, or wet liquids to improve mold release properties. , a method of adding alkyl ketene dimers, etc. has been proposed. In these methods, the releasability changes depending on the cleanliness of the heating drum surface, and as the drum surface gradually becomes dirty in about half a day, the releasability decreases, making it difficult to obtain cast coated paper with good quality. I can't do it anymore. Each time, the machine must be stopped and the drum surface treated with an oil-based substance again, making continuous operation over a longer period of time impossible with these methods. Furthermore, as a method to inactivate the heating drum surface and improve mold release properties, there is a method of treating the drum surface with acetic acid or nitric acid (US Pat. No. 2,943,954), a method of treating the drum surface with acetic acid or nitric acid, a method of treating the drum surface with methyl silicone resin (US Pat. No. 3,086,883), polyethylene, polypropylene, etc. , a method of coating the surface of the drum with polystyrene, polyester, polyethylene terephthalate, polyisobutylene, fluororesin, silicone resin, polyacrylic resin, polyvinyl chloride, etc.
No. 5-8105, Special Publication No. 35-11301, Special Publication No. 3
5-13705) has been proposed. In some cases, the above method shows good mold release properties, but there are problems such as the quality of the white cast coated paper, such as gloss and shine, is poor, and the surface treatment method of the drum is difficult, so it cannot be put into practical use. It has not been. Other methods include hydrophobic coating the surface of pigments used in paints, methods using breathable calcium carbonate and plastic pigments,
Alternatively, a method has been proposed that uses a copolymer of vinyl acetate and vinyl stearate, or a latex copolymerized with vinyl acetate or acrylonitrile in the latex used as an adhesive in paints, but none of these methods work. , long-term continuous operation is difficult. In particular, when Sachin White as a pigment is included in the coating layer, the mold releasability becomes even worse, and no matter which method is used, stable continuous operation for more than half a day is difficult. Therefore, in any of the conventional techniques, there is no method that can stably and continuously operate cast-coated paper with high gloss over a long period of time, which significantly reduces the productivity of cast-coated paper. is the current situation.

``Problems to be Solved by the Invention'' The present invention provides a method for stably and continuously producing cast coated paper of high quality over a long period of time.

"A Thousand Steps to Solve the Problem" The present invention provides a coating layer mainly composed of pigments and adhesives on base paper, and while the coating layer is in a wet state, the heating drum surface has a specular gloss. A method for producing cast-coated paper, which is produced by press-contacting the drum to give it a high-gloss finish, characterized in that the surface of the drum is coated with one or more fluorine-containing surfactants. "Function" In order to continuously operate high-quality cast-coated paper for long periods of time, the present inventors focused on surface treatment agents for drums that have a specular luster, and as a result of extensive research, they discovered that a specific fluorine-containing The inventors discovered that by coating the surface of the drum with a surfactant, long-term continuous operation is possible and high quality cast coated paper can be obtained, leading to the completion of the present invention. That is, in the method for producing cast coated paper of the present invention,
The surface of the heating drum used for producing the coated paper is coated with a fluorine-containing surfactant, more preferably the following general 2N), (It),
One or more of the compounds represented by (III), [IV] or [V] wJ. It is characterized by overturning it. O 11 (Rr-Z.-0)-IrP-+OM)s-a (
13Rt represents a perfluoroalkyl group or a perfluoroalkenyl group having 4 to 20 carbon atoms, and some of the fluorine atoms may be substituted with hydrogen atoms. n is 1 to 3
M is an alkali metal, an alkaline earth metal, zinc, an ammonium salt, an amine, a hydrogen atom, or a carbon number of 1
~20 alkyl groups. Z is a divalent bridging group bonded to the carbon atom of Rr and the oxygen atom of the phosphoric acid group. m represents an integer of 0 or l. As an example of 2, {-CI1
．． +▲, item 10) -4cn,h-,0 or R
R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). Specific examples of general formula (1) include the following.

? I CiF+sC11 ■CIIzOP(011)g,
0 C,. Ft+cHxO +CHzCHzO tr P(
Oll)z, CaF1yCHzCIIgOP(ONa
)z, (CsF+tel1gCIlzOhPOll,
Re Y- SOsM (II) Rr, m
and M are the same as (1). Y is a divalent bridging group bonded to the carbon atom and sulfur atom of Rf. An example of Y is a divalent bridging group bonded to the carbon atom. An example of U is R? -C-0 {- CIl■7 or CI1■0 {-CLcu■〇7 etc. (Here, i represents an integer of 1 to 20.) Specific examples of general formula (II) include the following.

CsF++SOJa. ．． C6F+3S03κ, C6Fl
3S03Nl14, CaF 1 7SO3Li, C?
F + ss03N (Czlls) a,C. F. S
O3Na, CaF+tOGSO3NaSCrF1sO
GSO3Nflg, C+Jz+ OGSOJ, Cs
F+tCOO(CIIJsSOJa,Cr+Fg3
CIIjO + CIlgCI120 isO=NaR
, -U. -COOM (Ill)R,,
m and M are the same as [I]. U is a carbon atom of R, a carboxylic acid group, etc. (Here, 1 is an integer of 1 to 20, R is a hydrogen atom or a carbon number of 1 to 20.
4 shows the alkyl group. ) Specific examples of general formula (III) include the following.

C? FISC00NI+4, II (CFt)vcOOON
a,C. IIS ■ C+oFg+(CI1t)sc00NI1n, CiFt
3SOzN-ClhCOOK, C311? C311, R R and the like.

R1 \? 3 R, and m are the same as in (1), R, , Rz and R are hydrogen atoms, alkyl groups having 1 to 10 carbon atoms, hydroxyalkyl groups, cycloalkyl groups, or 7 to 15 carbon atoms is an aralkyl group. X is
Halogen atom, OH, HSO. , CH3-SO4,
CH3COO or I1 PO. , (jl, -■1S
Anionic atoms and groups such as O3. ■ is Rf
is a divalent bridging group bonded to carbon atoms and nitrogen atoms. ■An example is R OR? SO■-N + Cllz h O + CHz t
T etc. (Here, i is an integer from 1 to 20, and j is an integer from 1 to 5.
The integer of 0 and R represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ) Specific examples of general formula [IV] include the following.

O CaF+tC-Nll+CIIz+N'' (
CI13) 31 -OCI+3 \ R, Rfs ■ and m are the same as above.

R4 and R, are R, and R, is the same as

A is COO or It is SO.

m is Indicates an integer of 0 or 1.

q is It is an integer from l to 4.

C113 What are the following specific examples of the general formula [■]? ? F
lssO■N +CI12 -h N' (CH3)! II- is mentioned. CSFIISO! NH + Cllg hOi Cllz
hN ”(CI+.)Co■ -0 1 C?Fl!IC-Nll +Clh h N”? CI1,) zcI■COO 0 11 CaF+tC-NH + Clb h N'' (CI13) 2 (CHz) 3COO -Ct.F
t+0-@SO! NH(CIlz)J”(CH3)
z (C}lx) 3SO:1ChF. SOJII (C
Ilz)sN”(CH3) z (CHz) 380
30 C+llt C311.1? sHt 7C. F. 50■N- (CHt) 3N ”?Czl
ls) zclI■C00- O C,F,1C-NH +CHz h N ” (CfbCHz011) z (CHz) scOO
−? ,F,,SO■NH(Cllz)+O(Cllz)
xN ”?Clls) gcII■C0〇1 Furthermore, the above general formula [I] ~ [
Specific examples of fluorine-containing surfactants other than (2) are as follows.

? Js 1 C1. F■0-{CllzCIlzO}i,■,C,P
．． ISOtN-{CIl■CIbO}is It 1
CI13? 11 C. F■C-0-{ClhCIhO}i o I mouth
, Csllt C113 C+ +h3SOtN {CIlzCIltO}T-■
, CTo? sF+t-{CIIzCII■Oh CJIzCll
zCsF+y, CllFl? SO! N-tCIlzC
HtUnL;tllL;lIgNbUz-t'l?
, CFs CF3 0 0? ．． P,%CHtCH■SCI{tCHtC-{CHt
CHzO｝T-薯0? CCHxCIhSCIbCll■C'lFIS11 0? vF l 9C11■C11■SC11zCllgO
→Cll■Cal■Ohichi? C11■ClhSClhC
ll■C9F + *CyF r sCO{CIIzC
lhO}T oOcctF + s,? 9F+ ,0@
cogo-{cll■CIIxO}m+cHgeOcq
Pt*,? u*cu■CIISOs I C. F. TSSO■NCII■Cll■CIl■N0(C
lls) xclIzcHz011? slL) 『CsF+ySO■N (CIlzClh011) tC
F. (ChCF!CFtO) z-CFCON (CIzC
HzOII) zCJ+sCIlz0? CHzCII■0}-r I1 C+ xFzscHzO {CIhCll,0}rr
HCF ac (CtF s) zc (CF s)=
C (CF 3) − 0 +Cll zcII go
hICI13,? 6F l 3CII■CI! 011,
? sF+ to {CllzCII■om Clls Typical specific examples of the fluorine-containing surfactant used to coat the surface of the cast drum include those listed above, but the present invention is of course limited to these. It's not a thing.

In general, fatty acids, paraffin, natural waxes, silicone compounds, fluorine compounds, etc. are widely used as mold release agents for molding plastics, etc., but under the specific conditions of producing cast coated paper, which is the object of the present invention. That is, basically, when a base paper is coated with an aqueous coating liquid containing pigments and an adhesive as main components, and this coating layer is pressed against the heated cast drum surface while it is in a wet state, In order to satisfy the contradictory conditions that the coating layer should adhere to the cast drum appropriately and then be reliably released from the cast drum after the coating layer dries, the fluorine-containing interface of the present invention must be applied. Only the activator can provide particularly stable continuous operation as a surface treatment release agent for cast drums, and can produce excellent cast coated paper without deteriorating gloss or printability. ．． Although the effects of the above-mentioned fluorine-containing surfactants used in the present invention are not necessarily clear, the perfluoroalkyl group possessed by the above-mentioned surfactants lowers the critical surface tension of the drum surface. This gives the cast drum surface suitable release properties for producing cast coated paper.
Furthermore, the hydrophilic groups of the above-mentioned surfactants provide affinity for the drum surface, and the bond between the drum surface and the fluorine-containing surfactant and the perfluoroalkyl groups are arranged in an orderly manner on the drum surface, reducing the critical surface tension of the drum surface. It is presumed that both of these properties have enabled unprecedented long-term continuous operation in the production of cast coated paper.

As described above, the present invention has revealed for the first time that long-term continuous operability is improved when the above-mentioned fluorine-containing surfactant is used as a coating agent on the surface of a cast drum.

Furthermore, compounds with hydrophilic groups such as those represented by the above general formulas (1) to [V] have a strong affinity with the drum surface, so
Shows excellent performance.

The method for coating the surface of the heating drum with the above-mentioned fluorine-containing surfactant is not particularly limited, but for example,
Direct application of a fluorine-containing surfactant or a fluorine-containing surfactant dissolved in a solvent or water, or a method such as a spray method or a dipping method, or a method such as a roll coater, air knife coater, brush coater, blade coater, etc. The coating machine applies the coating to the cast drum during or before and after operation, and if necessary, the coated surface is dried, heated, or puffed to form a uniform and thin coating layer.

The thickness of the coating layer at this time is approximately 0.01 to 100 μm. The solvent used to dissolve the fluorine-containing surfactant is not particularly limited, but water, an organic solvent, a mixture of water and an organic solvent, or a mixture of organic solvents can be used. Examples of organic solvents include alcohols such as methanol, ethanol, propanol, and isopropanol;
Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, ethers such as ethyl ether, isobrobyl ether, dioxane, tetrahydrofuran,
Examples include esters such as ethyl acetate and butyl acetate, and halogenated hydrocarbons such as dichloromethane, trichloroethane, chloroform, and trichlorofluoromethane.

Furthermore, the heating drum surface is coated with fatty acids, fatty acid soaps, sulfated castor oil, natural waxes such as carbana wax, oily substances such as paraffin wax and silicone oil, hydrocarbon surfactants, or fluorine-containing surfactants. It may be used in combination with an amide compound, etc., and the mixing ratio is 0.0 parts by weight of the oily substance, hydrocarbon surfactant, and fluorinated amide compound to 1 part by weight of the fluorinated surfactant. A suitable amount is 50 parts by weight, more preferably 0.1 to 10 parts by weight.

Thus, in the present invention, cast coated paper is produced using the above-mentioned specific heating drum, but the cast coated paper Kawahara paper is not particularly limited and is generally used in the field of cast coated paper. Acidic paper or neutral paper is applicable.

In addition, if necessary, a general pigment coating composition may be pre-coated with Oli on one or both sides of the base paper, and in that case, the coating amount is preferably about 5 to 30 g/po on dry weight per side. .

Furthermore, the coating composition for the cast coating layer is not particularly limited, and coating compositions containing pigments and adhesives as main components that are generally used in the cast coated paper field can be applied. be.

For pigments, one or more pigments for general coated paper, such as clay, kaolin, aluminum hydroxide, calcium carbonate, titanium oxide, barium sulfate, zinc oxide, satin white, and plastic pigments, are used as appropriate. It will be done.

In addition, adhesives include natural adhesives such as starch, modified starch, casein, soybean protein, and protein, synthetic adhesives such as styrene-butadiene copolymer latex, acrylic emulsion latex, butadiene-acrylonitrile copolymer latex, and polyvinyl alcohol. One or more types of natural and synthetic adhesives commonly used in water-based coating materials such as adhesives may be used in appropriate combinations. Generally, the amount of adhesive used is adjusted within the range of 5 to 50 parts by weight, more preferably 10 to 30 parts by weight, per 100 parts by weight of the pigment. In addition, fatty acids such as stearic acid, oleic acid, paltinic acid, their salts such as sodium, potassium, calcium, ammonium, zinc, etc., and sulfuric acid may be used as release agents in the coating composition, rewetting liquid, or gelling liquid. castor oil,
Conventionally known mold release agents such as hydrocarbon surfactants, polyethylene waxes, alkyl phosphates, sucrose higher fatty acid esters, lecithin, or the above-mentioned fluorine-containing surfactants may be blended as appropriate. The amount used is 0.01 to 10 parts by weight per 100 parts by weight of the pigment.
More preferably, it is adjusted within the range of 0.1 to 5 parts by weight. Furthermore, various auxiliary agents such as dispersants, waterproofing agents, preservatives, dyes, antifoaming agents, flow modifiers, etc. may be appropriately incorporated into the coating composition as required. The thus obtained coated material is coated onto base paper using an appropriate coating device such as an air knife coater, blade coater, brush coater, roll coater, size press, etc. so that the dry weight is approximately 5 to 35 g/m. The drum is coated, and while the coating layer contains water and is in a plastic state, it is pressed against the heated drum surface specified in the present invention and dried, and after the moisture in the coating layer is substantially evaporated, the drum Cast coated paper is obtained by releasing from the mold.

As a finishing method for such cast-coated paper, various conventionally known methods such as wet casting, rewet casting, and gelling casting can be used as they are. "Example" The present invention will be described in more detail below, but it is of course not limited thereto. In addition, unless otherwise specified, parts and percentages in the examples indicate parts by weight and percentages by weight, respectively. Example 1 Compound 1 shown in Table 1 was applied by spraying onto the surface of a chromium-plated mirror-glossy cast drum (5) with a diameter of 1500+u+ shown in FIG. 1 and dried. Separately,
55 parts of kaolin, 40 parts of light calcium carbonate, 5 parts of Sachin White, and 0.5 parts of sodium polyacrylate were dispersed in water using a Coles disperser to prepare a pigment slurry with a solid content concentration of 60%. To this slurry were added 0.5 parts of tributyl phosphine as an antifoaming agent, 1.0 parts of ammonium stearate as a mold release agent, 10 parts of a 15% casein aqueous solution (solid content) dissolved in ammonia as an adhesive, and acrylic acid. /putadiene/methyl methacrylate (ratio: 2/33/65) copolymer latex 16 parts (
3 parts of ZnSOn and water were added to prepare a coating liquid for casting with a solid content concentration of 45%, and a cast finish was performed using the rewet casting method using the apparatus shown in Figure 1. That is, the cast coating liquid prepared as described above was applied to a
g/m” casting base paper (1) with a dry weight of 20 g/
Coat with air knife coater (2) so that
Dry with air floating dryer (3). Next, this coated paper was rolled on a press roll (4
) and the press nip (6) formed by the above-mentioned surface-treated cast drum (5), where it passes through the nozzle (7).
After rewetting the coating layer surface with a certain rewetting liquid (0.5% concentration) from the polyethylene emulsion supplied from the company, it was pressed against a cast drum (5) with a surface temperature of 105°C at a press pressure of 200K g/cm. After drying,
A cast coated paper (9) was obtained by peeling it off from the cast drum with a take-off roll (8).

The operating speed at this time was 80 m/min. Example 2 In Example 1, Table 1 was used to treat the surface of the cast drum.
Cast coated paper was obtained in the same manner except that Compound 2 was used instead of Compound 1. Example 3 In Example 1, Table 1 was used to treat the surface of the cast drum.
Cast coated paper was obtained in the same manner except that Compound 3 was used instead of Compound 1. Example 4 In Example 1, Table 1 was used to treat the surface of the cast drum.
Cast coated paper was obtained in the same manner except that compound 4 was used instead of compound 1. Example 5 In Example 1, Table 1 was used to treat the surface of the cast drum.
A cast coated paper was obtained in the same manner except that Compound 5 was used instead of Compound 1.

Example 6 In Example 1, Table 1 was used to treat the surface of the cast drum.
A cast coated paper was obtained in the same manner except that Compound 6 was used instead of Compound 1.

Example 7 In Example 1, Table = 1 was applied to the treatment of the surface of the cast drum.
A cast coated paper was obtained in the same manner except that Compound 7 was used in place of Compound 1.

Example 8 In Example 1, Table 1 was used to treat the surface of the cast drum.
A cast coated paper was obtained in the same manner except that Compound 8 was used in place of Compound 1.

Example 9 In Example 1, Table 1 was used to treat the surface of the cast drum.
Cast coated paper was obtained in the same manner except that Compound 9 was used instead of Compound 1. Example 1O In Example 1, Table 1 was used to treat the surface of the cast drum.
Cast coated paper was obtained in the same manner except that compound 10 was used instead of compound 1. Example 11 In Example 1, Table 1 was used to treat the surface of the cast drum.
Cast coated paper was obtained in the same manner except that compound 11 was used instead of compound 1. Example 12 Cast coated paper was obtained in the same manner as in Example 1, except that Compound 12 was used instead of Compound 1 in Table 1 for treating the surface of the cast drum. Example 13 In Example 1, Table 1 was used to treat the surface of the cast drum.
A cast coated paper was obtained in the same manner except that Compound 13 was used in place of Compound 1.

Example 14 In Example 1, Table 1 was used to treat the surface of the cast drum.
Cast coated paper was obtained in the same manner except that Compound 14 was used instead of Compound 1. Example 15 In Example 1, Table 1 was used to treat the surface of the cast drum.
A cast coated paper was obtained in the same manner except that compound 15 was used instead of compound 1.

Example 16 In Example 1, Table 1 was used to treat the surface of the cast drum.
A cast coated paper was obtained in the same manner except that Compound 16 was used instead of Compound 1.

Example 17 Instead of compound 1, a mixture of compound 1 and stearic acid (
Cast coated paper was obtained in the same manner as in Example 1, except that a weight ratio of 10:90) was used.

Example 18 Cast coated paper was obtained in the same manner as in Example 1, except that a mixture of Compound 1 and Compound 15 (weight ratio 20:80) was used instead of Compound 1. Example 19 Cast coated paper was obtained in the same manner as in Example 1, except that a mixture of Compound 4 and Compound 16 (weight ratio 20:80) was used instead of Compound 1. Example 20 A mixture of compound 11 and compound 16 (instead of compound 1)
Cast coated paper was obtained in the same manner as in Example 1 except that a weight ratio of 10:90) was used.

Comparative Example 1 A cast coated paper was obtained in the same manner as in Example 1 except that the surface of the cast drum was used without any treatment.

Comparative Example 2 A cast coated paper was obtained in the same manner as in Example 1, except that stearic acid was applied to the surface of the cast drum instead of Compound 1.

Comparative Example 3 A cast coated paper was obtained in the same manner as in Example 1, except that the surface of the cast drum was coated with polystyrene instead of Compound 1 shown in Table 1. Comparative Example 4 Cast coated paper was obtained in the same manner as in Example 1, except that the surface of the cast drum was coated with polyethylene instead of Compound 1 in Table 1. Comparative Example 5 A cast coated paper was obtained in the same manner as in Example 1 except that silicone oil was used instead of Compound 1 in Table 1 on the surface of the cast drum.

As mentioned above, the continuous operation time and quality results of Examples 1 to 20 and Comparative Examples 1 to 5 are shown in Table 2.

Example 21 Compound 1 shown in Table 1 was applied by spraying onto the surface of a mirror-glossy, chromium-plated cast drum (b) having a diameter of 1500 mm as shown in FIG. 2 and dried.

65 parts of kaolin, 25 parts of light calcium carbonate, 5 parts of aluminum hydroxide, 5 parts of sachin white, 10 parts of sodium polyacrylate as a dispersant. 5 parts were dispersed in water using a Coles disperser to prepare a pigment slurry with a concentration of 70%.
Add to this 0.5 parts of triptyl phosphate as an antifoaming agent, 1.0 part of lecithin as a mold release agent, and 13 parts (solid content) of a 15% casein aqueous solution dissolved in ammonia as an adhesive.
, 1 part of styrene-butadiene copolymer latex (solid content), and water were added to obtain a coating liquid with a concentration of 55%. Using this cast coating liquid, a cast finish was performed using the gel casting method using the apparatus shown in Figure 2. That is, the cast coating liquid prepared as described above was applied to a
Dry weight is 20g/II in 1 g/1 casting base paper Ol.
The coated layer was coated with a roll coater (IQ) and then brought into contact with an aqueous calcium formate solution 02 having a concentration of 0.5% to gel the coated layer. Next, this paper was subjected to the above surface treatment using a press roll θ having a diameter of 750 mm and cast drum 04 (surface temperature 90
℃) with a press line pressure of 180 kg/cm, and after drying, it was peeled off from the cast drum with a take-off roll 05) to obtain a cast coated paper 06). The operating speed at this time is
The speed was 60m/min.

Example 22 Cast coated paper was obtained in the same manner as in Example 21 except that Compound 4 was used instead of Compound 1 in Table 1 on the surface of the cast drum.

Example 23 Cast coated paper was obtained in the same manner as in Example 21 except that Compound 7 was used instead of Compound 1 in Table 1 on the surface of the cast drum. Example 24 Cast coated paper was obtained in the same manner as in Example 21 except that Compound 1O in Table 1 was used instead of Compound 1 on the surface of the cast drum.

Example 25 A cast coated paper was obtained in the same manner as in Example 21 except that Compound 12 was used instead of Compound 1 in Table 1 on the surface of the cast drum.

Comparative Example 6 A cast coated paper was obtained in the same manner as in Example 21, except that stearic acid was applied to the surface of the cast drum instead of Compound 1 in Table 1.

Comparative Example 7 A cast coated paper was obtained in the same manner as in Example 21, except that silicone oil was used instead of compound 1 in Table 1 on the surface of the cast drum.

The continuous operation time and quality results of Examples 2l to 25 and Comparative Examples 6 and 7 are shown in Table 3. Example 26 Compound 1 shown in Table 1 was applied by spraying onto the surface of a mirror-glossy, chromium-plated cast drum (21) with a diameter of 3000 mm shown in FIG. 3 and dried.

As a coating liquid for casting, 60 parts of kaolin, 35 parts of light calcium carbonate, 5 parts of Sachin White, 12 parts of a 15% casein aqueous solution (solid content), and acrylic acid/butadiene/methyl methacrylate (ratio: 2/33/65) were used. A cast coating liquid with a concentration of 53% consisting of 12 parts (solid content) of polymer latex was prepared, and cast finishing was performed by a wet casting method using the apparatus shown in FIG.

That is, the cast coating liquid prepared as described above was heated to 60 yen
g/m” casting base paper 07) and the l!e device 0
Therefore, the dry weight is 10 g/m'', and then, while this coated layer is in a wet state, the second coating device 0!
In step 1, the same cast coating liquid as above was used with a dry weight of 10
g/ai” and immediately cut this paper into a diameter 8
Press the above-mentioned surface-treated cast drum (21) (surface temperature 80°C) with a 00mm press roll 121,
After drying, it was peeled off from the cast drum to obtain a cast coated paper (22). The operating speed at this time was 70 m/min.

Example 27 Cast coated paper was obtained in the same manner as in Example 26, except that Compound 4 was used instead of Compound 1 in Table 1 for the surface of the cast drum.

Example 28 Cast coated paper was obtained in the same manner as in Example 26 except that Compound 7 was used instead of Compound 1 in Table 1 on the surface of the cast drum.

Example 29 A cast coated paper was obtained in the same manner as in Example 26 except that Compound 1O was used instead of Compound 1 in Table 1 on the surface of the cast drum.

Example 30 A cast coated paper was obtained in the same manner as in Example 26 except that Compound 12 in Table 1 was used instead of Compound 1 on the surface of the cast drum.

Comparative Example 8 A cast coated paper was obtained in the same manner as in Example 26, except that stearic acid was applied to the surface of the cast drum instead of Compound 1 shown in Table 1. Comparative Example 9 A cast coated paper was obtained in the same manner as in Example 26, except that silicone oil was used instead of Compound 1 in Table 1 on the surface of the cast drum.

The continuous operation time and quality results of Examples 26 to 30 and Comparative Examples 8 and 9 are shown in Table 3. In addition, operability and quality evaluation were performed based on the following criteria.

(Continuous operation time) It is expressed as the time from the start of operation until a drum pick occurs or a satisfactory product cannot be produced due to paper sticking. (Gloss of cast surface) The gloss of the cast finished surface was measured according to the JIS P8142 method.

"Effects" As is clear from the results in Tables 2 and 3, the cast-coated paper obtained in the example of the present invention is a cast-coated paper that has excellent cast quality with high gloss on the cast surface. was achieved with high efficiency.

[Brief explanation of drawings]

FIGS. 1, 2, and 3 are schematic diagrams showing the manufacturing method of cast coated paper used in Examples and Comparative Examples of the present invention. (1), (10), (17): Base paper (Anwingu) (2): Air knife coder (3): Air floating dryer (4), (
13), (20): Press roll (5), (14)
, (21h cast drum (6): press nip (7): rewetting liquid (8), (15): take-off roll (9), (
16), (22): Cast 1/Coated paper (11)
: Roll coater (12) : Gelling solution (1B) : First coating device (19) : Second coating device Table-1

Claims (6)

[Claims] (1) Cast coating, in which a coating layer containing pigment and adhesive as main components is provided on base paper, and while the coating layer is in a wet state, it is pressed against the surface of a heating drum that has a specular gloss to give a strong gloss finish. 1. A method for producing cast-coated paper, characterized in that the surface of the drum is coated with one or more fluorine-containing surfactants. (2) The method for producing cast coated paper according to claim (1), wherein the fluorine-containing surfactant is a compound represented by the following general formula [I]. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [I] R_f represents a perfluoroalkyl group or perfluoroalkenyl group having 4 to 20 carbon atoms, and may be linear, branched, cyclic, or a combination thereof. Any of these may be used, and the main chain may further contain an oxygen atom, and some of the fluorine atoms may be substituted with hydrogen atoms, n is an integer of 1 to 3, M is an alkali metal, an alkali earth metals,
Indicates zinc, ammonium salt, amines, hydrogen atom, or alkyl group having 1 to 20 carbon atoms. Z is a divalent crosslinking group bonded to the carbon atom of R_f and the oxygen atom of the phosphoric acid group. m represents an integer of 0 or 1. (3) The method for producing cast coated paper according to claim (1), wherein the fluorine-containing surfactant is a compound represented by the following general formula [II]. R_f-Y_m-SO_3M [II] R_f, m and M are the same as in [I], Y is R_f
is a divalent bridging group bonded to a carbon atom and a sulfur atom. (4) The method for producing cast coated paper according to claim (1), wherein the fluorine-containing surfactant is a compound represented by the following general formula [III]. R_f-U_m-COOM [III] R_f, m and M are the same as in [I], U is R_f
is a divalent bridging group bonded to the carbon atom of the carboxylic acid group and the carbon atom of the carboxylic acid group. (5) The method for producing cast coated paper according to claim (1), wherein the fluorine-containing surfactant is a compound represented by the following general formula [IV]. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [IV] R_f and m are the same as in [I], R_1, R_2
and R_3 is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a hydroxyalkyl group, a cycloalkyl group, or an aralkyl group having 7 to 15 carbon atoms. X is a halogen atom, OH, HSO_4, CH_3SO_4, H_2PO
They are anionic atoms and groups such as _4, CH_3, COO, ▲numerical formulas, chemical formulas, tables, etc.▼. V is a divalent bridging group bonded to the carbon atom and nitrogen atom of R_f. (6) The method for producing cast coated paper according to claim (1), wherein the fluorine-containing surfactant is a compound represented by the following general formula [V]. ▲There are mathematical formulas, chemical formulas, tables, etc.▼[V] R_f and m are the same as in [I], R_4 and R_5
are the same as R_1 to R_3. A is COO or SO_3. V is a divalent bridging group bonded to the carbon atom and nitrogen atom of R_f. q is an integer from 1 to 4.