JP3658905B2 - Internal additive for papermaking and functional paper using the internal additive - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
INDUSTRIAL APPLICABILITY The present invention is used for wrapping paper or construction paper that requires various functions such as water resistance, water repellency, oil resistance, oil repellency, stain resistance, heat resistance, dry strength, and wet strength, particularly water resistance. It relates to water-resistant paper.
[0002]
[Prior art]
Conventionally, as a method of imparting various functions such as water resistance and oil resistance to paper, there are generally a method of imparting by processing during the papermaking process and a method of imparting by processing after the papermaking process.
[0003]
Processing during the paper making process includes sizing agents for internal addition (rosin, alkyl ketene dimer (AKD), alkenyl succinic anhydride (ASA), etc.), fixing agents (aluminum sulfate), and dry paper for internal addition. There is a method of making paper and drying by adding a force enhancer (cationic starch, polyacrylamide (PAM), plant gum, etc.), a wet paper strength enhancer for internal addition (polyaminoamide epichlorohydrin resin (PAE), etc.), etc. . Thereby, writability (prevention of water pen bleeding) and mild water resistance are imparted.
[0004]
As processing after the paper making process, there is a method of applying a surface sizing agent [starch type, polyvinyl alcohol (PVA) type, polyacrylamide (PAM) type, etc.) to the paper surface and drying. Thereby, writability (prevention of water pen bleeding), mild water resistance and printability are imparted.
[0005]
In addition, when making packaging paper or building paper that requires high water resistance, a method of generally laminating a plastic film such as polyethylene (PE) or polyethylene terephthalate (PET) on paper and acrylic A method of coating or impregnating with a resin such as a olefin resin or an olefin resin is used.
[0006]
However, the processing during the paper making process described above can provide writability (prevention of water-based pen bleeding) and mild water resistance, but this method can be applied to packaging paper or construction that requires high water resistance. It cannot be used for loaded paper.
[0007]
Further, since the end face of the paper is not processed in the processing after the paper making process, water and oil from that portion are generated, and thus there is a disadvantage that various functions of the paper are deteriorated.
[0008]
Organic-inorganic hybrid paper has been proposed as a technique for solving such problems (for example, JP-A-64-6198).
[0009]
This organic-inorganic hybrid paper is obtained by impregnating and adhering a polymer having a siloxane bond as a main chain bond to a paper substrate. This polymer has a siloxane bond made of an inorganic compound as a skeleton, and the side chain is an organic compound. Therefore, it is a resin that has both plasticity due to organic matter and heat resistance, weather resistance, and water resistance due to inorganic matter at the same time, and is impregnated into a paper substrate to achieve hybridization.
[0010]
However, since this organic-inorganic hybrid paper is produced by impregnating the above-mentioned polymer into a paper base material, polymer segregation occurs in the thickness direction in the paper base material, so Oils have the disadvantage of reduced functionality.
[0011]
[Problems to be solved by the invention]
The present invention has been made to solve the above-mentioned problems in water-resistant paper produced by a conventional technique, i.e., an internal additive that simultaneously combines plasticity due to organic matter and heat resistance, weather resistance, and water resistance due to inorganic matter. It is an object of the present invention to provide a water-resistant paper which is resistant to water immersion from the surface and end face of the paper in which the agent is internally added during the paper making process.
[0012]
[Means for Solving the Problems]
A first aspect of the present invention is a papermaking characterized by being a copolymer of a polymer of an organometallic compound represented by the general formula (1) and a polymer of an organometallic compound represented by the general formula (2) It is an internal additive.
[0013]
The internal additive for papermaking according to claim 1, which is a polymer of at least two kinds of organometallic compounds having different R's represented by the general formula (2).
[0014]
A third invention is a functional paper in which any one of the internal additives for papermaking in the first or second invention is internally added.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the internal additive for papermaking of the present invention will be described in detail.
[0020]
Examples of the organometallic compound represented by the general formula (1) include tetraethoxysilane and tetramethoxysilane.
[0021]
Examples of the organometallic compound represented by the general formula (2) include methyltriethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2- (3,4 -Epoxycyclohexyl) ethyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-trimethoxysilylpropyl-N, N, N-trimethylammonium chloride, Or octadecyl dimethyl (3-trimethoxysilylpropyl) ammonium chloride etc. can be illustrated.
[0022]
A method for producing a polymer or copolymer using the above organometallic compound is not limited, but as a catalyst for production by hydrolysis, hydrochloric acid, nitric acid, sulfuric acid, acetic acid, hydrofluoric acid, formic acid, phosphorus Acid, oxalic acid, ammonia or the like is used alone or in combination of two or more. In particular, hydrochloric acid is most preferable.
[0023]
Papermaking in for additive of the present invention is made of a polymer or copolymer obtained by similar hydrolysis, etc. by using the catalyst of the organometallic compound.
[0024]
As the pulp used in the present invention, bleached or unbleached kraft pulp, soda pulp, sulfite pulp, groundwood pulp, refiner groundwood pulp, thermomechanical pulp, etc. alone or 2 Use more than one type together.
[0025]
The water-resistant paper of the present invention is produced by internally adding the above-mentioned internal additive for papermaking into pulp slurry, and papermaking, pressing and drying.
[0026]
The internal additive for papermaking according to the present invention is a copolymer of a polymer composed of an organometallic compound represented by the general formula (1) and a polymer composed of an organometallic compound represented by the general formula (2), or Since it consists of a copolymer of a polymer composed of an organometallic compound represented by the formula (1) and a polymer composed of at least two or more types of organometallic compounds represented by the general formula (2), It becomes possible to combine plasticity and the like with properties such as heat resistance, weather resistance, and water resistance due to inorganic substances at the same time.
[0027]
Since the water-resistant paper according to the present invention is prepared by adding the paper additive according to the present invention during the paper making process, functionalization from all layers of the paper occurs, and from the surface and end surface of the paper. Has strong water resistance against water immersion.
[0028]
【Example】
Examples of the present invention will be described in detail below, but the present invention is not limited to the materials described in the examples.
[0029]
< Reference Example 1>
To 1 mol of tetraethoxysilane (manufactured by Chisso Corporation), 5 mol of 0.1N hydrochloric acid was added and stirred at room temperature for 30 minutes to prepare a polymer. Next, this was diluted to a 1.0 wt% solution when converted to SiO2 concentration using 0.1N hydrochloric acid to prepare an internal additive for papermaking.
[0030]
Separately, a pulp slurry in which a softwood bleached kraft pulp [beating degree 355 ml (csf)] and a hardwood bleached kraft pulp [beating degree 385 ml (csf)] are mixed at a weight ratio of 7: 3 [dry pulp concentration 1.57 wt% ] Was adjusted.
[0031]
The above papermaking internal additives to the pulp slurry (SiO ₂ concentration: 1.0 wt%) relative to the dry pulp mass, was added 1.0 wt%, stirred, subjected to paper making using a handmade square paper machine, A drying process (120 ° C.-5 min.) Was performed using a press (100 kgf-3 min.) And a Yankee dryer, and water-resistant paper having a basis weight of 315 g / m ² was produced.
[0032]
Reference Example 2 To 1 mol of methyltrimethoxysilane (manufactured by Chisso Corporation), 5 mol of 0.1N hydrochloric acid was added and stirred at room temperature for 30 minutes to prepare a polymer. Next, this was diluted to a 1.0 wt% solution when converted to SiO2 concentration using 0.1N hydrochloric acid to prepare an internal additive for papermaking.
[0033]
Separately, in the same manner as in Reference Example 1, Reference Example 1 and the same soft wood bleached kraft pulp [freeness 355ml (csf)] and hardwood bleached kraft pulp [freeness 385 ml (csf)] weight ratio of 7: so that 3 The mixed pulp slurry [dry pulp concentration 1.57 wt%] was prepared, and 1.0 wt% of the above papermaking internal additive (SiO2 concentration: 1.0 wt%) was added to the pulp slurry with respect to the dry pulp mass. Then, the paper is made using a hand-made square paper machine, a drying process (120 ° C.-5 min.) Using a press (100 kgf-3 min.) And a Yankee dryer, and a water-resistant paper having a basis weight of 315 g / m 2. Was made.
[0034]
<Example 3>
To a mixture of tetraethoxysilane (manufactured by Chisso Corporation) and methyltrimethoxysilane (manufactured by Chisso Corporation) in a molar ratio of 0.5: 0.5, 5 mol of 0.1N hydrochloric acid is added and room temperature is added. At 30 minutes to prepare a copolymer. Next, this was diluted to a 1.0 wt% solution when converted to SiO ₂ concentration using 0.1N hydrochloric acid to prepare an internal additive for papermaking.
[0035]
Separately, in the same manner as in Reference Example 1, Reference Example 1 and the same soft wood bleached kraft pulp [freeness 355ml (csf)] and hardwood bleached kraft pulp [freeness 385 ml (csf)] weight ratio of 7: so that 3 The mixed pulp slurry [dry pulp concentration 1.57 wt%] was prepared, and 1.0 wt% of the above papermaking internal additive (SiO2 concentration: 1.0 wt%) was added to the pulp slurry with respect to the dry pulp mass. Then, the paper is made using a hand-made square paper machine, a drying process (120 ° C.-5 min.) Using a press (100 kgf-3 min.) And a Yankee dryer, and a water-resistant paper having a basis weight of 315 g / m 2. Was made.
[0036]
<Example 4>
Methyltrimethoxysilane (manufactured by Chisso Corporation) and vinyltrimethoxysilane (manufactured by Chisso Corporation, Silaace S210) mixed in a molar ratio of 0.5: 0.5, 0.1N hydrochloric acid 5 mol Was added and stirred at room temperature for 30 minutes to prepare a copolymer. Next, this was diluted to a 1.0 wt% solution when converted to SiO ₂ concentration using 0.1N hydrochloric acid to prepare an internal additive for papermaking.
[0037]
Separately, in the same manner as in Reference Example 1, Reference Example 1 and the same soft wood bleached kraft pulp [freeness 355ml (csf)] and hardwood bleached kraft pulp [freeness 385 ml (csf)] weight ratio of 7: so that 3 The mixed pulp slurry [dry pulp concentration 1.57 wt%] was prepared, and 1.0 wt% of the above papermaking internal additive (SiO2 concentration: 1.0 wt%) was added to the pulp slurry with respect to the dry pulp mass. Then, the paper is made using a hand-made square paper machine, a drying process (120 ° C.-5 min.) Using a press (100 kgf-3 min.) And a Yankee dryer, and a water-resistant paper having a basis weight of 315 g / m 2. Was made.
[0038]
<Example 5>
Tetraethoxysilane (manufactured by Chisso Corporation), methyltrimethoxysilane (manufactured by Chisso Corporation), and vinyltrimethoxysilane (Silaso S210 made by Chisso Corporation) in a molar ratio of 0.2: 0.4: 0.4 The mixture was mixed with 5 mol of 0.1N hydrochloric acid and stirred at room temperature for 30 minutes to prepare a copolymer. Next, this was diluted to a 1.0 wt% solution when converted to SiO ₂ concentration using 0.1N hydrochloric acid to prepare an internal additive for papermaking.
[0039]
Separately, in the same manner as in Reference Example 1, Reference Example 1 and the same soft wood bleached kraft pulp [freeness 355ml (csf)] and hardwood bleached kraft pulp [freeness 385 ml (csf)] weight ratio of 7: so that 3 A mixed pulp slurry [dry pulp concentration 1.57 wt%] was prepared, and 1.0 wt% of the above papermaking internal additive (SiO2 concentration: 1.0 wt%) was added to the pulp slurry with respect to the dry pulp mass. Then, the paper is made using a hand-made square paper machine, a press (100 kgf-3 min.) And a drying process (120 ° C.-5 min.) Using a Yankee dryer, and a water-resistant paper having a basis weight of 315 g / m 2. Was made.
[0040]
<Comparative example 1>
As a comparative example, the same pulp slurry as in Reference Example 1 was used to prepare an additive-free paper to which no paper additive was added.
[0041]
The six types of samples (waterproof paper) thus prepared were subjected to 20 ° C., 65% RH. Based on JIS P8111 before the physical property evaluation. The humidity was adjusted for 24 hours or more in the environment.
[0042]
Six types of samples were dried (20 ° C, 65% RH.) And wet (sample pieces in distilled water) using an autograph (Shimadzu Autograph AG-500A manufactured by Shimadzu Corporation) based on JIS P8113. The breaking strength at 1 hour immersion) was measured. Using the results, the breaking stress was calculated from the following equation (a).
Breaking stress (kgf / mm ² ) = breaking strength (kgf) / sample cross-sectional area (mm ² ) (a)
[0043]
Further, using the rupture stress calculated above, the wet rupture stress / dry rupture stress ratio (wet / dry) was calculated from the following formula (b) to evaluate the water resistance.
wet / dry (%) = wet breaking stress (kgf / mm ² ) / dry breaking stress (kgf / mm ² ) × 100 (b)
The results are shown in Table 1.
[0044]
[ Table 1 ]
[0045]
As is clear from Table 1, Examples 3 to 5 had higher wet / dry values and higher water resistance than Comparative Example 1.
[0046]
【The invention's effect】
As described above, according to the present invention, it is possible to produce an internal additive having properties such as plasticity due to organic matter and heat resistance and water resistance due to inorganic matter.
Further, the paper using the internal additive of the present invention can be used as a wrapping paper or a construction paper that requires high water resistance.

Claims (3)

General formula
Si (OR) ₄ (1)
(Wherein R represents an alkyl group)
A polymer of an organometallic compound represented by
General formula
R ′ _m Si (OR) _4-m (2)
(In the formula, R ′ is a substituent having at least one of an alkyl group, a vinyl group, an epoxy group, and an amino group, R is an alkyl group, and m is the number of substitutions (0 <m <4)).
An internal additive for papermaking, comprising a copolymer with a polymer of an organometallic compound represented by the formula: The internal additive for papermaking according to claim 1, which is a copolymer with a polymer of at least two kinds of organometallic compounds having different R's represented by the general formula (2). A functional paper in which any of the internal additives for papermaking according to claim 1 or 2 is internally added.