JP2915241B2 - Papermaking sizing agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alkenyl succinic anhydride type papermaking sizing agent which is used by emulsification, and since the generation of dirt in a dryer portion is small, the generation of dirt on paper is suppressed. Moreover, the present invention relates to a sizing agent exhibiting an excellent sizing effect.

[0002]

2. Description of the Related Art In the manufacture of paper, fillers such as talc and clay are generally used in large quantities in order to improve printability, whiteness, and impart opacity. There is a growing movement to use calcium carbonate, which is present in large quantities and available inexpensively.

However, so-called anionic sizing agents such as rosin-based sizing agents generally used as papermaking sizing agents are used in an acidic sizing method of fixing to pulp with a sulfuric acid band, so that calcium carbonate is used as a filler. When used, there is a disadvantage that calcium carbonate is decomposed due to the acidity of the papermaking system.

[0004] Therefore, in order to solve this problem, various so-called neutral sizing agents which can be sized in a neutral region or an alkaline region without using a sulfate band have been proposed.

For example, Japanese Patent Publication No. 39-2305 discloses that
General formula

Embedded image (R is a dimethyl group and a trimethylene group; R 'is a group selected from an alkyl group, an alkenyl group, an aralkyl group, and an aralkenyl group each having 5 or more carbon atoms). 53-2852
No. 6 discloses a compound represented by the general formula R _x —CH ₂ —CH ＝ CH—CH ₂ —R _y (where R _x and R _y are each an alkyl group containing 4 to 10 carbon atoms). Sizing agents have been proposed which consist of the reaction product of the indicated internal olefin with maleic anhydride.

Japanese Patent Application Laid-Open No. 57-154495 discloses that maleic anhydride is added to a linear internal olefin mixture in which double bonds are almost uniformly distributed at positions other than the α-position having 8 to 10 carbon atoms. A sizing agent comprising a mixed alkenyl succinic anhydride obtained by the above method has been proposed.
No. 9-179898 discloses that the proportion of an olefin having 14 to 36 carbon atoms and having a double bond at the 2-, 3- and 4-positions is 10 to 65 mol%, respectively, and the total thereof is 70%. There has been proposed a sizing agent containing a reaction product obtained by an addition reaction of a linear olefin mixture of not less than mol% with maleic anhydride and / or a hydrogenated product of the reaction product. Also, Japanese Patent Application Laid-Open No. 60-990
Investigations on emulsifiers have also been carried out as described in 99.

These alkenyl succinic anhydride-type paper sizing agents are usually emulsified by a homomixer, homogenizer or the like using a water-soluble polymer compound such as cationized starch or a surfactant such as polyoxyalkylene aryl ether. Is added to the stock in the form of an aqueous emulsion,
In all cases, the emulsifying properties and the stability after emulsification were insufficient, so that there was a problem that a satisfactory size effect could not be obtained, or that the papermaking system of the pressed part from a chest called wet end was generated. . To solve this problem, as described in Japanese Patent Application No. 3-194980, a by-product is produced when an olefin is reacted with maleic anhydride to produce an alkenyl succinic anhydride (one-to-one adduct). There is a method of using a 1: 2 adduct and a decarboxylated product of the 1: 2 adduct to control the emulsified particle size to reduce stain.

[0008]

As described above, these alkenyl succinic anhydride type sizing agents have been improved in terms of sizing effect and reduction of stain on wet end. However, the generation of stains in the dryer section has not been reduced yet, and the problem of spots on the paper called "eyeballs and holes" caused by stains on the paper has not been solved at all. Previous studies did not elucidate the mechanism of the occurrence of spots on paper.If spots on paper occur, it is necessary to remove the part during winding work and commercialize it.From the viewpoint of productivity, reduction of spots on paper is not possible. It was a very important issue. However, it is difficult to solve this problem in the range of conventional techniques such as improvement of the structure of the raw material olefin, type of emulsifier, emulsification method, and the like, and a sizing agent based on a completely new concept has been desired.

It is an object of the present invention to provide a sizing agent which suppresses the occurrence of spots on paper since the occurrence of dirt on a dryer portion is small, and which exhibits an excellent sizing effect.

[0010]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to achieve this object, and as a result, have found the cause of dirt on the dryer portion, and have found that dirt on the dryer portion is the cause of the spots on the paper. This has led to the present invention. That is, the present inventor paid attention to and examined the dryer part contamination.

As a result, the soil is alkenyl succinic anhydride formed by reacting alkenyl succinic anhydride with water and alkenyl succinic acid salt formed by reacting with calcium carbonate. This meant that the succinic anhydride was volatilized. The boiling point of this alkenyl succinic anhydride was 400 ° C. or higher in terms of normal pressure, and it was unexpectedly expected that the alkenyl succinic anhydride would volatilize in the dryer portion at a temperature of about 150 ° C. Possibly, it is considered that water evaporating from the wet paper enters a steam distillation state, and is distilled under reduced pressure and volatilized. It is considered that the volatilized alkenyl succinic anhydride adhered to each part of the drier or the drier canvas, and eventually reacted with water or calcium carbonate used as a filler to form alkenyl succinic acid or a calcium salt, thereby forming dirt. Then, it was presumed that the dirt was peeled off on the surface of the paper and caused spots on the paper called “eyeballs and holes”.

It is further surprising that the carbon number distribution of the starting olefin used for the sizing agent is
In the case of alkenyl succinic acid and its calcium salt, which were collected as soil in the dryer part, the olefin content of C16 was 43% by weight, and that of C16 was much more concentrated. . Table 1 shows the analysis results.

[0013]

[Table 1]

[0014] Based on the above, the inventors of the present invention focused on the volatility of alkenyl succinic anhydride and conducted intensive studies. As a result, it was found that by increasing the number of olefin carbon atoms in the raw material of alkenyl succinic anhydride, the amount of alkenyl succinic anhydride volatilized can be reduced, thereby preventing the dryer portion from being stained and spots on paper. I came up with the invention. As described above, there has been no prior notice of controlling the olefin carbon number of the raw material of the alkenyl succinic anhydride type sizing agent in order to prevent contamination of the dryer portion and spots on the paper. It is an alkenyl succinic anhydride type sizing agent found from a viewpoint. In fact, most of the alkenyl succinic anhydride type sizing agents currently on the market are produced from olefins containing a large amount of 17 or less carbon atoms.

More specifically, the present invention is characterized in that the carbon number distribution is such that the number of carbon atoms is 17 or less, less than 5% by weight,
A linear internal olefin in which 8 or more are 95% by weight or more
(Not including α-olefin. Hereinafter, the same shall apply in the present invention.
Same. ) Is a papermaking sizing agent containing, as an active ingredient, an addition reaction product of maleic anhydride;
0 is 69 to 100% by weight, carbon number 21 or more is 30% by weight
A sizing agent for papermaking, characterized by containing an addition reaction product of a linear internal olefin and maleic anhydride, which is less than. The linear internal olefin used as a raw material may be one obtained by isomerizing a linear α-olefin having the above-mentioned carbon number distribution using a catalyst or one obtained by dehydrogenating n-paraffin. In order to accurately separate by distillation in numerical order, the number of carbon atoms produced by the polymerization of ethylene is two.
It is preferable to use the notched ethylene oligomer α-olefin after isomerization. The isomerization of an α-olefin can be carried out by the method described in JP-A-61-119797.

In order to maximize the performance of the present invention, it is desirable that the proportion of the olefin having 18 to 20 carbon atoms be large. When the content of the olefin having 17 or less carbon atoms increases, the occurrence of dryer fouling increases. Therefore, it is preferable that the content is less than 1% by weight, but it is preferable that the content is not substantially less than 5% by weight. As a result, dirt on the dryer can be reduced. An olefin having 21 or more carbon atoms may be contained, but if the content increases, the pour point rises and not only the handling becomes difficult, but also the temperature at the time of emulsification must be increased, and the emulsified particle size is increased. The size effect is also reduced due to roughening, so that it is preferable to suppress the content to less than 30% by weight.

The addition reaction between the linear internal olefin and maleic anhydride may be performed by any conventional method, with or without a catalyst. To give an example, it is heated to 180 to 250 ° C. under normal pressure or under pressure in the absence of a catalyst, preferably in an inert atmosphere such as nitrogen gas.
Performed for ~ 30 hours. There is no particular limitation on the molar ratio of the two, but it is preferable to use maleic anhydride at a ratio of 0.5 to 3 mol per mol of the olefin. Unreacted olefin and maleic anhydride are taken out of the system by distillation.

When sizing pulp using the papermaking sizing agent of the present invention containing the addition reaction product of the linear internal olefin and maleic anhydride obtained as described above, this sizing agent is usually used. Is added to the stock as an emulsion uniformly dispersed in water. To improve dispersion in water, various emulsifiers such as polyoxyalkylene sorbitan fatty acid ester, polyoxyalkylene sorbitol fatty acid ester, polyoxyalkylene alkyl ether, polyoxyalkylene alkyl aryl ether, fatty acid ester of polyhydric alcohol , Polyoxyalkylene alkyl ether sulfates, polyoxyalkylene alkyl ether phosphates, polyoxyalkylene alkyl aryl ether phosphates, polyoxyalkylene aralkyl aryl ether phosphates, and various cations as suspending agents. Active compounds such as cationized starch,
Cationic polyacrylamide or the like can be used alone or in combination.

The amount of the emulsifier used in combination with the maleic anhydride addition reaction product of the present invention is determined in consideration of the type of emulsifier, the dispersibility, etc., and is usually a linear internal olefin and maleic anhydride. 0.5 to the addition reaction product with
It is preferably from 20 to 20% by weight, more preferably from 1 to 10% by weight.

When a cationic compound is used as a suspending agent, the amount thereof is usually preferably 30 to 600% by weight, more preferably 30 to 600% by weight, based on the addition reaction product of a linear internal olefin and maleic anhydride. 100-300% by weight
It is.

Examples of the emulsifier include a homomixer, a homogenizer, a nozzle emulsifier, an orifice emulsifier,
An apparatus used for emulsifying a conventional alkenyl succinic acid type sizing agent such as a turbine emulsifying apparatus can be used as it is.

After emulsification, the sizing agent of the present invention can be added to the pulp slurry in any step of the papermaking process. The amount of the sizing agent of the present invention varies depending on the type of pulp to be used, papermaking conditions, paper use, and the like, but it is usually preferable to use 0.05 to 3.0% by weight based on the dry weight of the pulp.

In order to fix the sizing agent of the present invention to pulp, cationic compounds such as cationized starch, cationic polyacrylamide, and polyamine polyamide-epichlorohydrin resin are usually used as a fixing agent. 0.01 to dry weight of pulp
5.0% by weight is preferable, and more preferably 0.03 to
3.0% by weight. Any of these fixing agents can be added simultaneously with, before, or after the addition of the sizing agent. However, it is preferable to add it after the sizing agent in order to obtain an optimum fixing effect.

The sizing agent of the present invention can be used together with various sizing agents other than the present invention at an optional ratio, if desired.
It goes without saying that all types of fillers such as clay, titanium oxide, calcium carbonate, calcium sulfate, aluminum hydroxide and the like can be used.

[0025]

EXAMPLES Next, examples will be shown to specifically explain the present invention. Example 1 C ₁₈ (C _16: 0.1% by weight, C _18: 99.9 wt%) of the main component ethylene oligomer -α- olefin isomerized using nickel octoate catalyst and an alkyl aluminum catalyst. Obtained linear internal olefin (position distribution of double bond; 1 mol: 0 mol%, 2 mol: 13 mol%, 3 mol: 12 mol%)
Mol%, fourth position: 15 mol%, ⁵⁺ position: 60 mol%) 10
Then, 583 g of maleic anhydride (molar ratio to olefin: 1.5) was added to 00 g, and 215 g in an autoclave without a catalyst.
The reaction was performed at 8 ° C. for 8 hours. Unreacted olefin and maleic anhydride were removed from the reaction solution by distillation under reduced pressure to obtain 1320 g of an olefin maleic anhydride addition reaction product.

Example 2 C ₂₀ (C ₁₈ : 0.4% by weight, C ₂₀ : 98.2% by weight, C _20
22 : 1.4% by weight) The main component ethylene oligomer-α-olefin isomerized in the same manner as in Example 1 to obtain a linear internal olefin (double bond position distribution; 1 position: 0 mol%, 2nd: 12 mol%, 3rd: 11 mol%, 4th: 14
525 g of maleic anhydride (molar ratio to olefin: 1.5) was added to 1000 g of (mol%, 5 ⁺ position: 63 mol%), and 1250 g of olefin maleic anhydride addition reaction product was obtained according to the operation method of Example 1. .

Example 3 Carbon number distribution (C ₁₈ : 0.5% by weight, C ₂₀ : 28.0% by weight, C ₂₂ : 25.0% by weight, C ₂₄ : 19.0% by weight, C
_26: 15.0 wt%, C _28: 9.0 wt%, C ₃₀ or higher:
3.5% by weight) of an ethylene oligomer α-olefin isomerized in the same manner as in Example 1 to obtain a linear internal olefin (position distribution of double bonds; 1 mol: 0 mol%, 2 mol:
9 mol%, 3rd position: 9 mol%, 4th position: 12 mol%, 5
⁽⁺ Position: 70 mol%) Maleic anhydride 470 in 1000 g
g (to a molar ratio of olefin to 1.5) was added, and 1185 g of an olefin maleic anhydride addition reaction product was obtained according to the operation method of Example 1. This product has a melting point of 30 ° C.,
It was a solid at room temperature.

Comparative Example 1 An ethylene oligomer α-olefin having a carbon number distribution (C ₁₆ : 99.8% by weight, C ₁₈ : 0.2% by weight) was subjected to isomerization in the same manner as in Example 1 to obtain a linear chain. Internal olefin (double bond position distribution; 1 position: 0 mol%, 2 position: 13 mol%, 3 position: 12 mol%, 4 position: 17 mol%, 5 ⁺ position: 5
655 g of maleic anhydride (molar ratio to olefin: 1.5) was added to 1000 g of 8 mol%), and the olefin maleic anhydride addition reaction product 139 was added in accordance with the procedure of Example 1.
0 g was obtained.

Comparative Example 2 An ethylene oligomer α-olefin having a carbon number distribution (C ₁₆ : 56.8% by weight, C ₁₈ : 43.2% by weight) was prepared in Example 1.
The obtained linear internal olefin (double bond position distribution; 1 position: 0 mol%, 2 position: 12 mol%, 3 position: 12 mol%, 4 position: 15 mol%, ⁵⁺ : 6
623 g of maleic anhydride (molar ratio to olefin: 1.5) was added to 1000 g of 1 mol%), and the olefin maleic anhydride addition reaction product 136 was added in accordance with the operation method of Example 1.
0 g was obtained.

The olefin maleic anhydride addition reaction products of Examples 1 to 3 and Comparative Examples 1 and 2 were subjected to a heat loss measurement and a size effect measurement test.

(Measurement of Heating Weight Loss) 5 mg of the olefin maleic anhydride addition reaction products of Examples 1 to 3 and Comparative Examples 1 and 2 were put on a thermobalance (TGA-50, manufactured by Shimadzu Corporation) at a flow rate of 25 ml / min. 10 to 200 ° C in a nitrogen stream
The temperature was raised at a rate of ° C / min, and the weight loss rate at 200 ° C was measured.
The results are shown in Figure 1, the C ₁₇ or less in the raw material olefin 5
Sizing Agents of the Invention Containing Less than Wt.% Examples 1-3
Comparative Examples 1 to containing a large amount of olefins of ₁₇ or less
It can be seen that the volatilization loss is extremely small with respect to 2. A papermaking test was performed on the samples of Example 1 and Comparative Example 1 using an actual machine. As a result, Example 1 was particularly excellent in the degree of stains on the dryer and spots on the paper.

(Size Effect Measurement Test) Polyoxyethylene nonylphenyl ether (HLB13) was added to 10 g of the olefin maleic anhydride addition reaction product as an emulsifier.
5 g was added and mixed well. 1.5% to 1 g of this mixture
99 g of the cationized starch solution was added, and emulsification was performed at 7000 rpm for 2 minutes using a TK homomixer M type manufactured by Tokushu Kika Kogyo Co., Ltd.

[0033] The emulsified liquid was used as a 1% pulp slurry (LBK).
P, CSF = 430 ml) to which 0.1, 0.15 or 0.2% by weight of olefin maleic anhydride addition reaction product
Then, 0.8% by weight of the cationized starch (based on the pulp solids) and 0.03% by weight of the cationic polyacrylamide (based on the pulp solids) were added under stirring. In addition, papermaking was performed using a TAPPI standard sheet machine in a conventional manner. The filler used was light calcium carbonate, and the amount used was 20% by weight (based on pulp solids).

Next, the obtained wet paper was dewatered by compression, dried by heating at 105 ° C. for 1 minute with a rotary drier, and conditioned for 24 hours in a room at 20 ° C. and 65% relative humidity. The basis weight of the obtained hand-formed paper after humidity control is equivalent to 60 g / m ² . The sizing degree of the hand-made paper was measured by the Steckigt sizing degree test method of JIS P8122. Results are illustrated in Table 2, Example 3 a large amount containing more than C ₂₁ in the feed olefin showed slightly lower size effect, other sizing agents were almost the same effect.

[0035]

[Table 2]

[0036]

The sizing agent of the present invention is extremely excellent in suppressing the occurrence of stains on paper since the occurrence of stains in the dryer portion is small, and has an excellent sizing effect equal to or better than conventional products. Is shown.

[0037]

[Brief description of the drawings]

FIG. 1 shows the results of measuring the weight loss of the olefin maleic anhydride addition reaction products of Examples 1 to 3 and Comparative Examples 1 and 2 using a thermobalance.

Claims (2)

(57) [Claims] 1. The carbon number distribution is 5% by weight when the carbon number is 17 or less.
A papermaking sizing agent comprising an addition reaction product of a linear internal olefin (excluding an α-olefin) having a carbon number of 18 or less and 95% by weight or more and maleic anhydride. 2. The carbon number distribution is as follows: 1% by weight when carbon number is 17 or less.
, A linear internal olefin having from 18 to 20 carbon atoms of 69 to 100% by weight, and having 21 or more carbon atoms of less than 30% by weight
2. The papermaking sizing agent according to claim 1, further comprising an addition reaction product of (excluding an α-olefin) and maleic anhydride.