JP4439219B2 - Starch glue for corrugated cardboard - Google Patents

Description

  The present invention relates to a starch paste to which cardboard is bonded.

  In general, boron adhesives or boron compounds such as borax and boric acid are used as adhesive improvers for corrugated adhesives.

  By the way, in April 2001, a law (1999 Act No. 86, hereinafter referred to as “PRTR Law”) concerning the grasp of the discharge of specific chemical substances into the environment and the promotion of management improvements was enforced. It was. In the PRTR Law, if the amount of specified chemical substance used exceeds a certain amount, a notification obligation arises. And boron and its compound were designated as a designated substance of this PRTR method. This PRTR law is a law enforced for the purpose of protecting the global environment, and the reduction of the amount of boron and its compounds used is in line with the purpose of this law.

  On the other hand, Patent Document 1 discloses an adhesive for corrugated cardboard, which does not require boron or a compound thereof and is obtained by adding alkali to a low molecular weight starch and a silicate-containing material.

JP 2002-201445 A

  However, an adhesive that does not use boron or a compound thereof has a problem in that it can be used in a high-speed corrugated board bonding process because the initial adhesive strength is greatly reduced as compared with the case where boron or a compound thereof is used.

  Accordingly, the object of the present invention is to provide an adhesive for corrugated cardboard bonding that can exhibit sufficient initial adhesive strength to be practical in a high-speed corrugated cardboard bonding process while reducing the amount of boron used. And

  The present invention solves the above problems by using a starch paste for corrugated cardboard containing 0.05 to 5% by weight of a boron compound based on starch and containing a water-soluble metal compound and / or an acrylic polymer. It is.

  By producing a starch paste using a boron compound in combination with a water-soluble metal compound or an acrylic polymer, the initial adhesive strength of the starch paste for corrugated cardboard bonding can be made stronger than using each compound alone. . Thereby, starch paste with stronger initial adhesive strength can be obtained while reducing the amount of boron compound used than before. Further, the speed of the corrugated cardboard bonding process can be increased.

  The present invention is a starch paste for corrugated cardboard paste containing 0.05 to 5% by weight of a boron compound and containing a water-soluble metal compound and / or an acrylic polymer.

  As the starch, for example, raw starch such as corn starch, potato starch, wheat starch, sweet potato starch, tapioca starch, etc., and subjected to acid treatment, oxidation, etherification, esterification, grafting, enzyme modification, etc. Processed starch, or a mixture of a plurality of them may be mentioned. Alternatively, a mixture of a small amount of pregelatinized starch may be used.

  The boron compound needs to be 0.05 to 5% by weight, preferably 0.05 to 2.5% by weight, based on the starch. If the amount is less than 0.05% by weight, the amount of the boron compound is too small to increase the required initial adhesive strength. On the other hand, if it exceeds 5% by weight, the amount of the boron compound is too large, and it becomes too easy to be designated by the PRTR method, which is not preferable. In addition, as said boron compound, what can bridge | crosslink starches and can increase an apparent molecular weight is desirable, and sodium tetraborate (borax) is the most desirable.

  Examples of the water-soluble metal compound include a water-soluble aluminum compound, a water-soluble zirconium compound, a water-soluble titanium compound and the like. These may use only 1 type and may use 2 or more types together.

  Examples of the water-soluble aluminum compound include aluminum nitrate, aluminum silicate, aluminum sulfate, sodium aluminate, polyaluminum chloride, ammonium ammonium sulfate (ammonium alum), potassium aluminum sulfate (potassium alum), sodium aluminum sulfate (sodium alum), Aluminon etc. are mentioned.

  Examples of the water-soluble zirconium compound include zirconium dichloride oxide, zirconium chloride, zirconium oxychloride such as zirconium oxychloride, acidic zirconyl sulfate trihydrate such as zirconate disulfate trihydrate, zirconium carbonate, ammonium zirconium carbonate, Zirconium acetate, zirconyl ammonium acetate, zirconium stearate, zirconium nitrate, zirconium phosphate, zirconium silicide and the like can be mentioned.

  Examples of the water-soluble titanium compound include tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, tetramethyl titanate, titanium acetylacetonate, titanium tetraacetyl acetate, titanium ethyl acetoacetate, titanium octane. Examples thereof include diolate, dihydroxybis (ammonium lactate) titanium, titanium lactate, titanium triethanolamate, polyhydroxytitanium stearate, and the like.

  The addition ratio in the case of adding these water-soluble metal compounds to the above-mentioned starch paste for corrugated board bonding is desirably 0.01 to 10% by weight with respect to starch, and is 0.02 to 0.5% by weight. More desirable. If it is less than 0.01% by weight, the effect of adding almost cannot be expected. On the other hand, when it exceeds 10% by weight, the viscosity of the resulting starch paste for corrugated cardboard bonding becomes very high, which may make it difficult to use.

  The weight ratio of the water-soluble metal compound to the boron compound is preferably 1: 10000 to 50: 1, and more preferably 1: 1000 to 5: 1. It is because the effect by adding may not be able to be exhibited when there are too few said water-soluble metal compounds. In addition, since at least the boron compound needs to be contained in the amount described above, if the amount of the water-soluble metal compound is excessively much more than that, the properties of the water-soluble metal compound may become too remarkable.

  Examples of the acrylic polymer include (meth) acrylamides (meaning at least one of “methacrylamides” and “acrylamides”, hereinafter “(meth)” is equivalent to this) and (meth) A polymer containing at least one of acrylic acid and (meth) acrylic acid ester as a polymerization component is desirable.

  Examples of the (meth) acrylamides include (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, and N, N-diethyl (meth). N-substituted (meth) acrylamides such as acrylamide, N-isopropyl (meth) acrylamide, Nt-octyl (meth) acrylamide, N-methylol (meth) acrylamide, and secondary amino groups such as alkylallylamine and diallylamine A vinyl monomer etc. are mentioned.

Examples of the acrylic acids include (meth) acrylic acid.
Examples of the (meth) acrylic acid esters include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl (meth) acrylate. , (Meth) acrylic acid-sec-butyl, (meth) acrylic acid pentyl, (meth) acrylic acid heptel, (meth) acrylic acid-2-ethylhexyl, (meth) acrylic acid lauryl, (meth) acrylic acid stearyl, ( (Meth) acrylic acid cyclohexyl, (meth) acrylic acid benzyl, (meth) acrylic acid methoxypolyethylene glycol, (meth) acrylic acid ethoxypolyethylene glycol, (meth) acrylic acid methoxypolypropylene glycol, (meth) acrylic acid-2-hydroxyethyl Etc., tertiary amino group-containing vinyl Ma and the like.

  Examples of the tertiary amino group-containing vinyl monomer include dialkylaminoalkyl alcohols such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, diethylaminopropyl (meth) acrylate, and the like ( Examples include dialkylaminoalkyl (meth) acrylates that are esters with (meth) acrylic acid, and dialkylaminoalkyl (meth) acrylamides such as dimethylaminopropyl (meth) acrylamide and diethylaminopropyl (meth) acrylamide.

  The above (meth) acrylamides, (meth) acrylic acids, and (meth) acrylic esters may be used alone or in combination of two or more. In addition, when there are (meth) acrylic acid or (meth) acrylic acid ester among the monomers to be copolymerized, a part or all of the polymer becomes a water-soluble salt in the case of (meth) acrylic acid. In the case of (meth) acrylic acid esters, the water-soluble part may be saponified.

  Examples of the water-soluble salt of (meth) acrylic acid include alkali metal salts such as sodium salt and potassium salt of (meth) acrylic acid and ammonium salt.

  The saponified water-soluble portion of the (meth) acrylic acid ester means a saponified ester group of the (meth) acrylic acid ester. Here, examples of the carboxylate include alkali metal salts such as sodium salt and potassium salt, and ammonium salts.

  Among the acrylic polymers, a polymer containing (meth) acrylamide or (meth) acrylic acid is preferable because it is excellent in water solubility and aggregation performance, and polyacrylamide is particularly desirable.

  The acrylic polymer may be copolymerized with other monomers in addition to the acrylamides, the acrylic acid, and the acrylic esters. Examples of the other monomers that can be copolymerized in addition to the acrylamides include anionic vinyl monomers, cationic vinyl monomers, polyfunctional vinyl monomers, nonionic vinyl monomers, and the like. Or two or more of them may be used in combination.

The anionic vinyl monomer is a vinyl monomer having an anionic (anionic) property in an aqueous solution. Examples of the anionic vinyl monomer include at least one of a carboxyl group-containing vinyl monomer, a sulfonic acid group-containing vinyl monomer, and a phosphonic acid group (—PO (OH) ₂ ) -containing vinyl monomer.

  Examples of the carboxyl group-containing vinyl monomer include unsaturated monocarboxylic acid, unsaturated dicarboxylic acid, unsaturated tricarboxylic acid, unsaturated tetracarboxylic acid, and salts thereof.

  Examples of the unsaturated monocarboxylic acid include acrylic acid and methacrylic acid. Examples of the unsaturated monocarboxylic acid salt include alkali metal salts such as sodium salt and potassium salt of the unsaturated monocarboxylic acid and ammonium salts. Etc. These may be used alone or in combination of two or more.

  Specific examples of the unsaturated dicarboxylic acid include maleic acid, fumaric acid, itaconic acid, citraconic acid, and the like. Specific examples of salts of the unsaturated dicarboxylic acid include, for example, those of the unsaturated dicarboxylic acid. Examples thereof include alkali metal salts such as sodium salt and potassium salt, and ammonium salt. These may be used alone or in combination of two or more.

  Specific examples of the unsaturated tricarboxylic acid include aconitic acid, 3-butene-1,2,3-tricarboxylic acid, 4-pentene-1,2,4-tricarboxylic acid, and the like. Specific examples of the tricarboxylic acid salts include alkali metal salts such as sodium salts and potassium salts of the above unsaturated tricarboxylic acids, ammonium salts, and the like. These may be used alone or in combination of two or more.

  Specific examples of the unsaturated tetracarboxylic acid include 1-pentene-1,1,4,4-tetracarboxylic acid, 4-pentene-1,2,3,4-tetracarboxylic acid, and 3-hexene-1. , 1, 6, 6-tetracarboxylic acid, and the like. Specific examples of the salts of the unsaturated tetracarboxylic acid include alkali metal salts such as sodium salt and potassium salt of the unsaturated tetracarboxylic acid and ammonium salts. Etc. These may be used alone or in combination of two or more.

  Examples of the sulfonic acid group-containing vinyl monomer include unsaturated sulfonic acids and their salts. Specific examples of the unsaturated sulfonic acid include vinyl sulfonic acid, styrene sulfonic acid, (meth) allyl sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid, and the like. Specific examples thereof include alkali metal salts such as sodium salt and potassium salt of unsaturated sulfonic acid and ammonium salt. These may be used alone or in combination of two or more.

  Examples of the phosphonic acid group-containing vinyl monomer include unsaturated phosphonic acids and their salts. Specific examples of the unsaturated phosphonic acid include vinylphosphonic acid and α-phenylvinylphosphonic acid. Specific examples of the unsaturated phosphonic acid salts include a sodium salt of the unsaturated phosphonic acid, Examples thereof include alkali metal salts such as potassium salt and ammonium salt. These may be used alone or in combination of two or more.

  These anionic vinyl monomers may be used alone or in combination of two or more.

  As the anionic vinyl monomer, among those listed above, for example, at least one selected from the group consisting of unsaturated monocarboxylic acids, unsaturated dicarboxylic acids, and salts thereof from the viewpoints of paper quality improvement effect and economy, etc. Particularly preferred is at least one selected from the group consisting of itaconic acid, acrylic acid and salts thereof. The combined use of an acrylamide polymer copolymerized with the above anionic vinyl monomer and alginic acids can maintain the desired degree of anionization as a whole even if the amount of anionic polysaccharide alginic acid used is reduced. There is a merit that can be reduced.

  The cationic vinyl monomer is a vinyl monomer having a cation (cation) property in an aqueous solution. Examples of the cationic vinyl monomer include the tertiary amino group-containing vinyl monomer and the secondary amino group-containing vinyl monomer, allylamine which is a primary amino group-containing vinyl monomer, and amino group-containing vinyl monomers including these. And quaternary ammonium salt-containing vinyl monomers.

  Examples of the secondary amino group-containing vinyl monomer include the compounds described above. Examples of the tertiary amino group-containing vinyl monomer include alkyl diallylamine and dialkylallylamine in addition to the above-described compounds.

  Examples of the salts of the amino group-containing vinyl monomer include inorganic acid or organic acid salts of the amino group-containing vinyl monomer and hydrochloric acid, sulfuric acid, formic acid, acetic acid, and the like.

  Examples of the quaternary ammonium salt-containing vinyl monomer include alkyl halides such as methyl chloride and methyl bromide, alkyl halides such as benzyl chloride and benzyl bromide, dimethyl sulfate, diethyl sulfate, epichlorohydrin, and 3-chloro-2- It can be obtained by reacting a quaternizing agent such as hydroxypropyltrimethylammonium chloride or glycidyltrialkylammonium chloride with the tertiary amino group-containing vinyl monomer. Specifically, 2-hydroxy-N, N, N, N ′, N′-pentamethyl-N ′-[3-{(1-oxo-2-propenyl) amino} propyl] -1,3-propanedi And ammonium dichloride.

  As said cationic vinyl monomer, these said substances may be used only by 1 type, and may use 2 or more types together.

  Examples of the polyfunctional vinyl monomer include bifunctional vinyl monomers such as di (meth) acrylates, bis (meth) acrylamides, divinyl esters, epoxy acrylates, urethane acrylates, trifunctional vinyl monomers, Examples thereof include a tetrafunctional vinyl monomer and a water-soluble aziridinyl compound. These may be used alone or in combination of two or more.

  Examples of the di (meth) acrylates include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, and glycerin di (meth). An acrylate etc. are mentioned. These may be used alone or in combination of two or more.

  Examples of the bis (meth) acrylamides include methylene bis (meth) acrylamide, ethylene bis (meth) acrylamide, hexamethylene bis (meth) acrylamide, N, N′-bisacrylamide acetic acid, and N, N′-bisacrylamide methyl acetate. N, N-benzylidenebisacrylamide and the like. These may be used alone or in combination of two or more.

  Examples of the divinyl esters include divinyl adipate and divinyl sebacate. These may be used alone or in combination of two or more.

  The trifunctional vinyl monomer refers to a monomer having three vinyl groups in the compound. In addition, the description of a functional vinyl monomer is based on this. Examples of the trifunctional vinyl monomer include 1,3,5-triacryloylhexahydro-S-triazine, triallyl isocyanurate, N, N-diallylacrylamide, triallylamine, triallyl trimellitate and the like. . These may be used alone or in combination of two or more.

  Examples of the tetrafunctional vinyl monomer include tetramethylolmethane tetraacrylate, tetraallyl pyromellitate, N, N, N ′, N′-tetraallyl-1,4-diaminobutane, tetraallylamine salt, and tetraallyloxyethane. Etc. These may be used alone or in combination of two or more.

  Examples of the water-soluble aziridinyl compound include tetramethylolmethane-tri-β-aziridinylpropionate, trimethylolpropane-tri-β-aziridinylpropionate, 4,4′-bis (ethyleneiminecarbonyl). Amino) diphenylmethane and the like. These may be used alone or in combination of two or more.

  Other examples of the polyfunctional vinyl monomer include water-soluble polyfunctional epoxy compounds and silicon compounds. These may be used alone or in combination of two or more.

  Examples of the water-soluble polyfunctional epoxy compound include (poly) ethylene glycol diglycidyl ether, (poly) propylene glycol diglycidyl ether, (poly) glycerin diglycidyl ether, (poly) glycerin triglycidyl ether, and the like. These may be used alone or in combination of two or more.

  Examples of the silicon compound include 3- (meth) acryloxymethyltrimethoxysilane, 3- (meth) acryloxypropyldimethoxymethylsilane, 3- (meth) acryloxypropyltrimethoxysilane, and 3- (meth). Examples include acryloxypropylmethyldichlorosilane, 3- (meth) acryloxyoctadecyltriacetoxysilane, 3- (meth) acryloxy-2,5-dimethylhexyldiacetoxymethylsilane, vinyldimethylacetoxysilane, and the like. These may be used alone or in combination of two or more.

  Examples of other multifunctional vinyl monomers include allyl (meth) acrylate, diallyl phthalate, diallyl malate, diallyl succinate, diallyl acrylamide, divinyl benzene, diisopropenyl benzene, N, N-diallyl methacrylamide, N -Methylol acrylamide, diallyl dimethyl ammonium, diallyl chlorendate, glycidyl (meth) acrylate, etc. can be mentioned. These may be used alone or in combination of two or more.

  The nonionic vinyl monomer is a vinyl monomer having no ionicity in an aqueous solution. Examples of the nonionic vinyl monomer include esters of the alcohol and (meth) acrylic acid, (meth) acrylonitrile, styrene, styrene derivatives, vinyl acetate, vinyl propionate, methyl vinyl ether, N-vinylacetamide, and the like. These may be used alone or in combination of two or more.

  Furthermore, as the acrylic polymer, Mannich-modified products or Hoffmann degradation products of these acrylic polymers can be used.

  The addition ratio when adding these acrylic polymers to the starch paste for corrugated board bonding is desirably 0.01 to 20% by weight with respect to starch, and more preferably 0.02 to 2% by weight. desirable. If it is less than 0.01% by weight, the effect of adding it may be hardly achieved. On the other hand, when it exceeds 20% by weight, the viscosity of the starch paste for corrugated cardboard bonding becomes very high, which may make it difficult to use.

  The weight ratio of the acrylic polymer to the boron compound is preferably 1: 1000 to 100: 1, and more preferably 1: 100 to 50: 1. It is because the effect by adding may not be able to be exhibited when there are too few said acrylic polymers. In addition, since at least the boron compound needs to be contained in the above-described amount, if the amount of the acrylic polymer is excessively more than that, the properties of the acrylic polymer may become too remarkable.

  The acrylic polymer preferably has a viscosity average molecular weight of 500,000 to 30,000,000, more preferably 1,000,000 to 10,000,000. If the viscosity average molecular weight is less than 500,000, the effect of improving the adhesive strength may not be sufficiently exhibited. On the other hand, if the viscosity average molecular weight exceeds 30,000,000, the viscosity becomes too high and it may be difficult to handle.

  Furthermore, when the water-soluble metal compound and the acrylic polymer are used in combination, the weight ratio of the water-soluble metal compound and the acrylic polymer is desirably 1: 100 to 1: 1, and 1:50 ˜1: 2 is more desirable. If the amount of the water-soluble metal compound is larger than that of the acrylic polymer, the effect of imparting viscosity by the acrylic polymer may not be sufficiently exhibited. Moreover, when the ratio of the water-soluble metal compound is less than 1/100 of the acrylic polymer, the initial adhesive force may be greatly reduced when a shearing force is applied by stirring.

  In addition, the weight ratio of the boron compound and the additive that is a combination of the water-soluble metal compound and the acrylic polymer is desirably 1: 1000 to 100: 1, and is 1: 100 to 100: 2. More desirable. If the amount of the boron compound is too small, the initial adhesive strength may be lowered too much. On the other hand, if the amount of the boron compound is too large, it may be environmentally undesirable.

  In addition, when adding the water-soluble metal compound, the acrylic polymer, and the boron compound to the starch paste as a thickener, each may be added continuously to the starch paste for corrugated cardboard or simultaneously. Good. Moreover, after adding each to the said starch paste for cardboard pasting of two liquids or three liquids or more, you may mix them.

  In addition to the above thickener, the starch paste for corrugated board bonding preferably contains a starch swelling agent. The starch swelling agent refers to a substance that provides an alkaline environment to the starch paste in order to swell the aqueous dispersion of the starch and to crosslink the starch with the thickener. For example, sodium hydroxide or potassium hydroxide.

  The starch swelling agent in the starch paste for corrugated cardboard bonding is preferably 0.2 to 1.0% by weight with respect to the starch. When the starch swelling agent is less than 0.2% by weight, the alkalinity of the starch paste for corrugated cardboard bonding is too weak, the gelatinization temperature becomes too high, and the effect of crosslinking the starch by the thickener. May become insufficient. On the other hand, if it exceeds 1.0% by weight, the gelatinization temperature becomes too low and gelation may occur, resulting in a state where it cannot be stored.

  In producing the starch paste for corrugated cardboard bonding according to the present invention, the solid content of the above thickener, starch swelling agent, starch, etc., the mixing ratio with water in the general starch paste for corrugated cardboard bonding Can be produced. Here, the double water ratio, which is the weight of water relative to the solid content, is desirably 2 to 5.

  By using the boron compound together with the water-soluble metal compound or the acrylic polymer, the effect of increasing the apparent molecular weight by crosslinking with the starch is enhanced, and only the conventional boron compound is used as a thickener. For the corrugated board paste, the initial adhesive strength and viscosity are superior to the starch paste for the corrugated board paste using only the above-mentioned starch paste for corrugated board, the above water-soluble metal compound and the above acrylic polymer as the thickener. A starch paste can be obtained. Moreover, since the intensity | strength per unit amount goes up, the usage-amount of a boron compound can also be suppressed.

  Hereinafter, the present invention will be described more specifically with reference to experimental examples and comparative examples. A starch paste was prepared by the method described below, and the Ford cup viscosity and B-type viscosity of the starch paste immediately after obtained were measured by the methods listed below. Further, 1000 g of the obtained adhesive was transferred to a plastic container having a volume of 1 liter, and a stirring rod having one propeller blade having a diameter of 65 mm was attached to a 90 W motor with a water bath at 40 ° C. and stirred at 600 rpm. Ford cup viscosity, B-type viscosity, and initial adhesive strength one hour after the completion of the starch paste were measured by the methods listed below. In the table, an acrylic polymer, a water-soluble metal compound, and a boron compound are collectively referred to as a thickener. The double water ratio is the weight ratio of water to the total amount of starch combined with tapioca and corn starch.

[Measurement of Ford Cup viscosity]
Ford cup by measuring the time (seconds) at which a predetermined amount (95.567 ml) of starch paste to be measured is dropped at 40 ° C. using a cup conforming to the all-stage Ford cup (20 ° C. water for 10 seconds). Viscosity (unit: seconds) was used. Hereinafter, the Ford cup viscosity is expressed as “FCV”. The above-mentioned “all-stage Ford cup (20 ° C. water for 10 seconds)” is a Ford cup certified by the National Corrugated Cardboard Industry Association, and when water at a water temperature of 20 ° C. is used, a predetermined amount (95. 567 ml) refers to a Ford cup that takes 10 seconds to drip.

[Measurement of type B viscosity]
Using a BM type rotational viscometer manufactured by Tokyo Keiki Co., Ltd. No. 3 rotor was used to measure the viscosity of the starch paste to be measured at a liquid temperature of 40 ° C. to obtain a B-type viscosity (unit: cps).

[Measurement of initial bond strength]
Single-sided cardboard (width 50 mm, length 85 mm, medium shin: Rengo Co., Ltd. KS120 (basis weight: 120 g / m ² ), liner: Rengo Co., Ltd. RKA220: basis weight 220 g / m ² ) On the top, the starch paste to be measured is applied at 5 g / m ^{2 when} absolutely dried. And after placing on the cradle with the center shin facing up, the fixing pin for fixing on the single-sided cardboard cradle between the steps of the middle shin and not rising with respect to the cradle The group and the ascending pin group that rises and separates from the cradle are inserted alternately.

Thereafter, a liner piece (RKA280 manufactured by Rengo Co., Ltd .: basis weight 280 g / m ² ) is placed on the top of the single-sided cardboard, and heated with a hot plate at 175 ° C. for a predetermined time from above the liner piece. Raise the group and peel off the liner piece affixed to the top of the single-sided cardboard, and measure the peeling force of the liner piece at that time with a load cell (Orientec Co., Ltd .: TLB-100L-F) for initial adhesion. Strength.

[Measurement after 1 hour]
The obtained starch paste was transferred to a plastic container having a volume of 1 liter, and a stirring rod having one propeller blade having a diameter of 65 mm was attached to a 90 W motor in a water bath at 40 ° C. and stirred at 600 rpm. Using the starch paste one hour after the start of stirring, the FCV, B-type viscosity, and initial adhesive strength were measured by the above methods.

[Starch paste containing polyacrylamide and borax]
( Reference Example 1)
<Step 1> In 951.97 g of water kept at 40 ° C. in an octagonal stainless steel container having a volume of 5 liters in a 40 ° C. water bath, 81.72 g of raw corn starch (manufactured by Oji Corn Starch Co., Ltd.). The stirring rod having one propeller blade with a diameter of 65 mm and one turbine blade with a diameter of 55 mm was attached to a 120 W motor and stirred and dispersed at 400 rpm.
<Step 2> Thereafter, 93.12 g of 15 w / w% sodium hydroxide (manufactured by Kishida Chemical Co., Ltd.) is added to a metering pump (manufactured by Tokyo Rika Machinery Co., Ltd .: MICRO TUBE PUMP MP-3). (During the dropping, the stirring speed is changed to 600 rpm, 1000 rpm, and 2200 rpm as the liquid thickens), and when the dropping is completed, the stirring speed is changed to 2400 rpm and the dropping of the sodium hydroxide aqueous solution is started. Continue stirring for another 30 minutes.
<Step 3> Thereafter, the stirring speed is changed to 1650 rpm, 890.73 g of water having a water temperature of 40 ° C. is added, and stirring is performed for 5 minutes. Thereafter, 28.65 g of raw tapioca and 600.33 g of raw corn starch were added over 2 minutes. <Step 3 ′> Three minutes later, the stirring speed was changed to 1000 rpm, and a 1.5 wt% polyacrylamide aqueous solution ( 188.07 g of Paralock 2A111 manufactured by Asada Chemical Industry Co., Ltd. is added), and after stirring for 3 minutes, sodium tetraborate (US Borax, borax: same applies below) 5.73 g is added, and stirring is performed 12 minutes later. Stopped.
<Sizing solution> Double water ratio 2.96, sodium hydroxide concentration (hereinafter referred to as “caustic concentration”) 0.49 wt%, starch polyacrylamide ratio to 0.40 wt%, starch borax ratio 0.81 wt % Starch paste was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

(Experimental example 1 )
In Reference Example 1, 886.9 g of water was used instead of 890.73 g of water at 40 ° C. in <Step 3>, and <Step 3 ′> was changed to the following: “After 1 minute, the stirring speed was changed to 2400 rpm, titanium 4.01 g of lactate (manufactured by Matsumoto Pharmaceutical Co., Ltd .: 10 times diluted product of ORGATICS TC-310) is added, and after stirring for 2 minutes, 188.07 g of a 1.5 wt% polyacrylamide aqueous solution is added. minutes was added sodium tetraborate 5.73g after stirring, except for using the stirring was stopped. "after 12 minutes was carried out in the same manner as in reference example 1.
<Glue solution> Double water ratio 2.96, caustic concentration 0.49 wt%, starch polyacrylamide ratio 0.40 wt%, starch titanium lactate ratio 0.025 wt%, starch borax ratio 0.81 wt% % Starch paste was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

(Experimental example 2 )
In Experimental Example 1 , the initial amount of water in <Step 1> was 960.76 g, the raw corn starch was 83.41 g, the 15 w / w% sodium hydroxide aqueous solution in <Step 2> was 94.37 g, and <Step 3 > Then change the stirring speed to 1650 rpm, add 949.22 g of water with a water temperature of 40 ° C. and stir for 5 minutes. Then, 40.1 g of raw tapioca and 589.36 g of raw corn starch for 2 minutes 1 minute later, the stirring speed was changed to 2400 rpm, 2.4 g of titanium lactate was added, and after stirring for 2 minutes, 112.84 g of a 1.5 wt% polyacrylamide aqueous solution was added. It was added sodium 8.02 g, except for using the stirring was stopped. "after 12 minutes was performed in the same manner as in experimental example 1.
<Glue solution> Double water ratio 2.95, caustic concentration 0.50 wt%, starch polyacrylamide ratio 0.24 wt%, starch titanium lactate ratio 0.015 wt%, starch borax ratio 1.125 wt% % Starch paste was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

(Experimental example 3 )
In Experimental Example 1 , the initial amount of water in <Step 1> was 969.55 g, the raw corn starch was 85.09 g, the 15 w / w% sodium hydroxide aqueous solution in <Step 2> was 95.62 g, and <Step 3 > Then, change the stirring speed to 1650 rpm, add 1011.54 g of water with a water temperature of 40 ° C. and stir for 5 minutes. Then, add 51.56 g of raw tapioca and 578.39 g of raw corn starch for 2 minutes. 1 minute later, the stirring speed was changed to 2400 rpm, 0.8 g of titanium lactate was added, 37.61 g of a 1.5 wt% polyacrylamide aqueous solution was added after 2 minutes of stirring, and 4 minutes after stirring for 1 minute. The same procedure as in Experimental Example 1 was conducted except that 10.31 g of sodium acid was added and stirring was stopped after 12 minutes.
<Glue> Double water ratio 2.94, Caustic concentration 0.51 wt%, Polyacrylamide ratio to starch 0.08 wt%, Titanium lactate ratio 0.005 wt%, Starch borax ratio 1.442 wt% % Starch paste was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

( Reference Example 2 )
In Experimental Example 1 , the 15 w / w% sodium hydroxide aqueous solution of <Step 2> was 94.57 g, the water charged in <Step 3> was 862.72 g, and the ammonium zirconium carbonate solution was used instead of 4.01 g of titanium lactate. (Daiichi Rare Element Chemical Co., Ltd .: 10-fold diluted product of zircosol AC-7, the same applies hereinafter) The same procedure as in Experimental Example 1 was performed except that 27.13 g was added.
<Sizing agent> Double water ratio 2.96, caustic concentration 0.499 wt%, starch polyacrylamide ratio 0.397 wt%, starch zirconium carbonate ratio 0.05 wt%, starch borax ratio 0.81 A weight percent starch paste was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

[Starch paste containing sodium polyacrylate and borax]
( Reference Example 3 )
In Reference Example 1, the water in <Step 1> was 951.57 g, the raw corn starch was 81.68 g, the 15 w / w% sodium hydroxide aqueous solution in <Step 2> was 94.58 g, and <Step 3 > Then change the stirring speed to 1650 rpm, add 793.67 g of water at a water temperature of 40 ° C. and stir for 5 minutes. Then, 28.62 g of raw tapioca and 600.09 g of raw corn starch for 2 minutes <Step 3 ′> Three minutes later, the stirring speed was changed to 1000 rpm, and 282 g of a 0.5 wt% sodium polyacrylate aqueous solution (parada 100A 102 manufactured by Asada Chemical Industry Co., Ltd.) was introduced, was added sodium tetraborate 5.72g after 1 minute stirring, except for using the stirring was stopped after 12 minutes. ", it was carried out in the same manner as in reference example 1.
<Glue solution> A starch paste having a double water ratio of 2.96, a caustic concentration of 0.50 wt%, a sodium polyacrylate ratio of 0.20 wt%, and a starch borax ratio of 0.81 wt% was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

(Experimental example 4 )
In Reference Example 3 , the water in <Step 3> was changed to 789.84 g, <Step 3 ′> and the following were changed: “After 1 minute, the stirring speed was changed to 2400 rpm, 4.01 g of titanium lactate was added, and after stirring for 1 minute, It was carried out in the same manner as in Reference Example 3 except that 5.73 g of sodium borate was added and stirring was stopped after 12 minutes.
<Glue> Double water ratio 2.96, Caustic concentration 0.50% by weight, Sodium polyacrylate ratio 0.20% by weight, Titanium lactate ratio 0.025% by weight, Starch borax ratio 0. 81 wt% starch paste was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

( Reference Example 4 )
In Experimental Example 3 , the 15 w / w% sodium hydroxide aqueous solution of <Step 2> was 96.33 g, the water of <Step 3> was 905.66 g, <Step 3 ′> The stirring speed was changed, 27.13 g of ammonium zirconium carbonate solution was stirred for 2 minutes, and then 141.05 g of 0.5 wt% aqueous sodium polyacrylate was added, and after stirring for 1 minute, 5.72 g of sodium tetraborate was added. The procedure was the same as Reference Example 3 except that stirring was stopped after a minute.
<Glue solution> A starch paste having a double water ratio of 2.96, a caustic concentration of 0.51 wt%, a sodium polyacrylate ratio of 0.10 wt%, and a starch borax ratio of 0.81 wt% was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

[Starch paste containing water-soluble metal compound and borax]
( Reference Example 5 )
In Reference Example 1, the water in <Step 1> was 951.6 g, the raw corn starch was 81.69 g, the 15 w / w% sodium hydroxide aqueous solution in <Step 2> was 100.34 g, and <Step 3>"Then, change the stirring speed to 1650 rpm, add 1062.21 g of water at a water temperature of 40 ° C and stir for 5 minutes. Then, 28.62 g of raw tapioca and 600.11 g of raw corn starch for 2 minutes 3 minutes later, the stirring speed was changed to 2400 rpm, 8.02 g of titanium lactate was added, 5.72 g of sodium tetraborate was added after stirring for 3 minutes, and stirring was stopped after 12 minutes. " The same procedure as in Reference Example 1 was performed except that.
<Glue solution> A starch paste having a double water ratio of 2.97, a caustic concentration of 0.53% by weight, a ratio of titanium lactate to starch of 0.05% by weight, and a ratio of starch borax of 0.81% by weight was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

( Reference Example 6 )
In Reference Example 1, the water in <Step 1> was 952.04 g, the raw corn starch was 81.72 g, the 15 w / w% sodium hydroxide aqueous solution in <Step 2> was 100.37 g, and <Step 3>. Change the stirring speed to 1650 rpm, add 1002.96 g of water with a water temperature of 40 ° C., and stir for 5 minutes. Then, 28.65 g of raw tapioca and 600.37 g of raw corn starch for 2 minutes 3 minutes later, the stirring speed was changed to 2400 rpm, 67.82 g of ammonium zirconium carbonate was added, 5.73 g of sodium tetraborate was added after stirring for 3 minutes, and stirring was stopped after 12 minutes. " The procedure was the same as in Reference Example 1 except that.
<Glue liquid> A starch paste having a double water ratio of 2.96, a caustic concentration of 0.53% by weight, a zirconium ammonium carbonate ratio of 0.124% by weight, and a starch borax ratio of 0.81% by weight was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

[Starch paste without water-soluble metal compound and acrylic polymer]
(Comparative Example 1)
In Reference Example 1, 850 g of water in <Step 1>, 75 g of raw corn starch, 84 g of 15 w / w% sodium hydroxide aqueous solution in <Step 2>, <Step 3> Change the stirring speed to 910 g of water at a water temperature of 40 ° C. and stir for 5 minutes, then add 50 g of raw tapioca and 500 g of raw corn starch over 2 minutes, and then stir at 2400 rpm after 4 minutes. changing the speed, the four added sodium borate 10 g, except for using the stirring was stopped after 12 minutes. "I was carried out in the same manner as in reference example 1.
<Glue solution> A starch paste having a double water ratio of 2.93, a caustic concentration of 0.508 wt%, and a starch borax ratio of 1.6 wt% was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

[Starch paste without borax]
(Comparative Example 2)
In Reference Example 1, 930 g of water in <Step 1>, 77.5 g of raw corn starch, 90 g of 15 w / w% sodium hydroxide aqueous solution in <Step 2>, <Step 3> , Change the stirring speed to 1650 rpm, add 731.1 g of water at a water temperature of 40 ° C., and stir for 5 minutes, then add 627.75 g of raw corn starch over 2 minutes, and then stir to 2400 rpm after 1 minute changing the speed, the addition of titanium lactate 8.01 g, 2 min 1.5 wt% polyacrylamide aqueous 376.13g after stirring was added, except for using the stirring was stopped after 13 minutes. "same manner as in reference example 1 Went to.
<Glue solution> A starch paste having a double water ratio of 3.00, a caustic concentration of 0.475% by weight, a starch polyacrylamide ratio of 0.8% by weight, and a starch titanium lactate ratio of 0.05% by weight was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

(Comparative Example 3)
In Reference Example 1, the water in <Step 1> is 930 g, the raw corn starch is 77.5 g, the 15 w / w% sodium hydroxide aqueous solution in <Step 2> is 93 g, <Step 3> The stirring speed was changed to 1650 rpm, 731.1 g of water having a water temperature of 40 ° C. was added, and the mixture was stirred for 5 minutes, and then 627.75 g of raw corn starch was added over 2 minutes, and after 1 minute, the stirring speed was increased to 2400 rpm. In addition, 8.83 g of titanium lactate was added, and after stirring for 2 minutes, 542.9 g of a 0.5% aqueous sodium polyacrylate solution was added, and stirring was stopped after 13 minutes. "
The procedure was the same as in Reference Example 1 except that.
<Glue solution> A starch paste having a double water ratio of 2.97, a caustic concentration of 0.495% by weight, a ratio of sodium polyacrylate to starch of 0.4% by weight, and a ratio of starch titanium lactate of 0.05% by weight was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

(Comparative Example 4)
In Reference Example 1, <Step 1> water was 930 g, raw corn starch was 77.5 g, <Step 2> 5 w / w% sodium hydroxide aqueous solution was 104.5 g, and <Step 3> “Then, the stirring speed was changed to 1650 rpm, 1082.52 g of water having a water temperature of 40 ° C. was added, and the mixture was stirred for 5 minutes. Thereafter, 627.75 g of raw corn starch was added over 2 minutes, and after 1 minute, 2400 rpm changing the stirring rate, was added titanium lactate 16.03G, except for using the stirring was stopped after 15 minutes. "was carried out in the same manner as in reference example 1.
<Glue solution> A starch paste having a double water ratio of 3.00, a caustic concentration of 0.55% by weight, and a starch titanium lactate ratio of 0.1% by weight was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

(Comparative Example 5)
In Reference Example 1, <Step 1> water was 930 g, raw corn starch was 77.5 g, <Step 2> 15 w / w% sodium hydroxide aqueous solution was 104.5 g, <Step 3> “Then, the stirring speed was changed to 1650 rpm, 963.09 g of water having a water temperature of 40 ° C. was added, and the mixture was stirred for 5 minutes. Thereafter, 627.75 g of raw corn starch was added over 2 minutes, and 1400 minutes later, 2400 rpm changing the stirring rate, was added ammonium zirconium carbonate 135.63G, except for using the stirring was stopped after 15 minutes. "it was performed in the same manner as in reference example 1.
<Glue solution> A starch paste having a double water ratio of 3.00, a caustic concentration of 0.55% by weight, and a ratio of zirconium ammonium carbonate to 0.25% by weight of starch was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

[Production by two-component mixing]
(Experimental example 5 )
500 g of the starch paste containing borax obtained in Comparative Example 1 and 500 g of the starch paste containing no borax obtained in Comparative Example 2 were put into a 1-liter plastic container, and the diameter was 65 mm in a 40 ° C. water bath. A stirring rod having one propeller blade was attached to a 90 W motor, stirred at 600 rpm, and after 10 minutes, a double water ratio of 2.96, a caustic concentration of 0.49% by weight, and a starch polyacrylamide ratio of 0.40% by weight, A starch paste having a starch titanium lactate ratio of 0.025% by weight and a starch borax ratio of 0.81% by weight was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

(Experimental example 6 )
270 g of starch paste containing borax obtained in Comparative Example 1 and 630 g of starch paste containing no borax obtained in Comparative Example 2 were put into a 1 liter plastic container, and the diameter was 65 mm in a 40 ° C. water bath. A stirring rod having one propeller blade was attached to a 90 W motor, stirred at 600 rpm, and after 10 minutes, a double water ratio of 2.95, a caustic concentration of 0.498% by weight, a starch polyacrylamide ratio of 0.24% by weight, A starch paste having a ratio of titanium lactate to starch of 0.015% by weight and a ratio of starch borax of 1.13% by weight was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

(Experimental example 7 )
90 g of starch paste containing borax obtained in Comparative Example 1 and 810 g of starch paste containing no borax obtained in Comparative Example 2 were put into a 1-liter plastic container, and the diameter was 65 mm in a 40 ° C. water bath. A stirring rod having one propeller blade was attached to a 90 W motor, stirred at 600 rpm, and after 10 minutes, a double water ratio of 2.94, a caustic concentration of 0.505% by weight, and a starch polyacrylamide ratio of 0.08% by weight, A starch paste having a ratio of titanium lactate to starch of 0.005% by weight and a ratio of starch borax of 1.44% by weight was obtained.
This starch paste was measured by the above measuring method. The results are shown in Table 1.

Claims (4)

Starch paste for corrugated board paste containing 0.05-5% by weight of boron compound with respect to starch and containing water-soluble titanium compound and water-soluble salt of poly (meth) acrylamide or poly (meth) acrylic acid . The starch paste for corrugated board bonding according to claim 1 , wherein an addition ratio of the water-soluble titanium compound is 0.01 to 10% by weight with respect to the starch. The starch for corrugated board bonding according to claim 1 or 2 , wherein the addition ratio of the water-soluble salt of poly (meth) acrylamide or poly (meth) acrylic acid is 0.01 to 20% by weight with respect to the starch. paste. The starch paste for corrugated board bonding according to any one of claims 1 to 3 , wherein the water-soluble salt of poly (meth) acrylamide or poly (meth) acrylic acid has a viscosity average molecular weight of 500,000 to 30,000,000. .