JPS5860095A - Amphoteric paper strengthening agent - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an amphoteric paper strength agent based on acryl ΣF, specifically, an amphoteric paper strength agent that can be used in a wide pH range and can stably produce excellent paper strength in this pH range. Moreover, the present invention relates to a paper strength agent containing a specific amphoteric water-soluble polymer as an active ingredient, which improves the redisintegrability of paper obtained using the same.

Paper is made by adding various paper-making chemicals such as paper strength agents, sizing agents, and fixing agents to an aqueous slurry of pulp, and then dried vkO-
It is manufactured by being rolled up into a roll. In the above-mentioned winding process, paper that cannot be used as a product, that is, paper that cannot be used as a product, is required for the inner ear portion and the O-ru connection, and the amount of paper that cannot be used as a product is usually a few percent or more of the paper that is made.
Occurs in about 10% of cases. This waste paper is generally re-disintegrated and reused as a pulp source, but if this re-disintegration is insufficient, the quality of the paper obtained using it will be non-uniform and the commercial value will be significantly reduced. Particularly in the production of medium to high quality paper such as writing paper and printing paper, it is essential to sufficiently re-disintegrate the waste paper. As described above, in the paper manufacturing process, it is desired to impart excellent paper strength to the resulting paper, while also imparting good redisintegration properties so that the waste paper can be easily redisintegrated. The paper strength of paper is naturally greatly influenced by the performance of the paper strength agent used in the papermaking process, but the above-mentioned redisintegration properties are also significantly affected by the paper strength agent used. It was discovered that. In other words, paper strength agents that have been proposed in the past as being able to be used in a wide pH range and impart a certain degree of paper strength to paper, regardless of whether or not a sulfuric acid SO fixing agent is used in the papermaking process. In general, the paper strength itself is not satisfactory, and as the paper strength increases, it tends to reduce the redisintegration property of the waste paper, and it is difficult to have the performance of paper sheets for dormitory use. It turns out. For example, the WI polymer of acrylanid yarn obtained by reacting polyacrylanid with hypochlorite in an alkaline region is stable in its aqueous solution, and the initial zero paper strength effect can be achieved within a few days at room temperature. There is a drawback that the paper strength is reduced by half, and there is also a drawback that the redisintegration property of the above-mentioned broken paper is significantly reduced when a sufficient paper strength effect can be achieved. Maku Acrylic Anide, Acrylic Acid and Methacrylic Acid Lua!
Amphoteric copolymers obtained by copolymerizing noethyl ester or its ester, and amphoteric copolymers obtained by reacting acrylanido-acrylic acid copolymers have also been proposed as paper strength agents. The paper strength effect is still not sufficient. Moreover, the former has the disadvantage that it is difficult to impart the desired constant paper strength to the paper, especially when the papermaking system I is neutral or alkaline, and the latter has the disadvantage that the above-mentioned paper strength effect is insufficient. The redisintegrability of the waste paper is also low and unsatisfactory. Furthermore, according to the research of the present inventor, an amphoteric copolymer consisting of acrylanidide, acrylic acid, and a specific acrylanidium conductor represented by the general formula (1) described later has sufficient paper strength for paper making. However, the redisintegrability of the waste paper was quite poor.

Currently, paper strength agents that have satisfactory performance as paper strength agents, such as those on boards, and in particular, have the ability to impart extremely superior paper strength to paper without reducing the redisintegration properties of broken paper, have not yet been developed. Not yet.

The present inventor has discovered that regardless of the presence or absence of a fixing agent such as sulfuric acid, it can be used in a wide range of pH ranges, and that it can always stably exhibit excellent paper strength effects, and that the resulting product can be We conducted extensive research with the aim of creating a paper strength enhancer that would also improve the redisintegration properties of paper (broken paper). As a result, a water-bathable copolymer consisting mainly of acrylani-F and a predetermined amount of α, β-unsaturated monocarboxylic acid, specific acrylic acid esters, and specific acrylamide derivatives was obtained. The present inventors have found that the above objects are met and have now completed the present invention.

That is, the present invention provides: 1) α,β-unsaturated heptanocarboxylic acid and/or its alkali *Reference C (hereinafter referred to as 1 component)
0v nyl%, b) General formula n3 [wherein] is 2.3 or 4. R□ Indicates a hydrogen atom or a methyl group. In addition, R2 and R3 each represent an alkyl group having 1 to 4 carbon atoms, or a 6-membered heteroall group together with the nitrogen atom to which the 2-terminal is bonded. At least 10 to 50 cationic salts selected from acid addition salts and quaternary salts thereof (hereinafter referred to as -11 component), and a general formula [wherein, Misaki is 2.3 or 4, R4 is Indicates a hydrogen atom or a methyl group. In addition, R5 and R6 are the same or different from A, and represent an alkyl group having from 4 to 4 carbon atoms, or together with the nitrogen atom to which they are bonded, represent a 6-membered heterocyclic group. At least one cationic t-mer selected from acid esters, acid addition salts thereof, and quaternary salts thereof (hereinafter referred to as b-
(hereinafter referred to as component C) 1 to 20 °C 1% to 20%, d) acrylamide (hereinafter referred to as component C) 40 to 98% by mole, and d) component 1 above. An amphoteric paper characterized in that the active ingredient is a water-soluble copolymer copolymerizable with component C to another nonionic T polymer (hereinafter referred to as component L) having a composition of 0 to 50F. Concerning stimulants.

The paper strength agent of the present invention exhibits an excellent paper strength enhancing effect that remains virtually unchanged in a wide range of alkaline to acidic ranges, for example, levels H4 to H9, especially when no sulfuric acid is used. Even when the amount of feces is small, it can impart good paper strength to paper, and it also has the characteristics of imparting good re-disintegration properties so that the waste paper can be easily re-disintegrated. In addition, the paper strength enhancer of the present invention also promotes the size reduction of soap-type or emulsion-type zero-size sizing agents, aluminum ketene timer sizing agents, etc., which are commonly used in paper manufacturing, It has the ability to reduce the dose of the drug.

The water-soluble copolymer that is the active ingredient of the paper strength enhancer of the present invention is
It can be obtained by copolymerizing predetermined amounts of the above four to one components.

Specific examples of component C include acrylic acid, methacrylic acid, etc., and their alkali salts, such as alkali metal salts such as caustic acid and caustic potash, and isoelectric salts of ammonium salts.

The l component consists of a b-1 component and a -12 component.

As component b-1, the compound represented by the above general formula (1), its acid addition salt, and its quaternary salt can be used alone or in combination of two or more. Part-1! General formula (1) as a component
In the acrylanido derivative represented by R2 and R3, examples thereof include methyl, ethyl, propyl, and butyl groups. , t R2 and R3
Examples of the 6-membered heterocyclic group that can be formed with the nitrogen atom to which it is bonded include, for example, a seven-membered heterocyclic group, a divelidino group, a divelidino group, and the like. Preferred specific examples of the acrylanido derivative used as the b-1 component are as follows.

Dimethylacrylia! dimethylaminobutyl acrylanid, dimethylaminobutyl acrylanid, diethylaminoethyl acrylanido, diethylaminobutyl acrylanid, diethylaminobutyl acrylanid, G-Yaku-Projilua! Noethyl Acrylica! Do, G, Lua! Nobuojiru acrylanilide, etc. and methacrylanidide derivatives corresponding thereto.

Examples of acid addition salts of the above compound O include hydrochloric acid, sulfuric acid, nitric acid,
Examples include water-soluble acid addition salts to which an inorganic acid such as phosphoric acid or an organic acid such as formic acid, acetic acid, pyro7iosic acid, or oxalic acid is added. (9) As the quaternary salt of the above compound 0, any ordinary quaternary salt obtained by known quaternization means can be used. The quaternizing agents used in the quaternization include ordinary quaternizing agents except those having crosslinking properties, such as ethyl bromide, butyl bromide, benzyl bromide, methyl chloride, ethyl chloride, benzyl chloride, methyl iodide, Inorganic acid esters such as Alcoluparite or Aralluhalite, dimethyl sulfate, diethyl sulfate, dimethyl sulfite, and dimethyl phosphate can be used. In the above, the use of a crosslinking quaternizing agent, such as a cross-linking quaternizing agent, is undesirable because it tends to impair the redisintegration properties of broken paper in the resulting amphoteric paper strength agent. Above 4! l
Of course, quaternization with a curing agent may be carried out in advance on the compound of formula (1) or the heptaO salt prior to the production of the copolymer according to the present invention, or Formulas contained in the aftercough copolymer [! ] It is also possible to carry out the treatment on a portion corresponding to the compound.

As the b-2 component, the compound represented by the above general formula (1), its acid addition salt, and its quaternary salt can be used alone or in combination of two or more. General formula for the above h-2 component [
The definition of R5 and R6 in the above-mentioned general formula (1) is
It is the same as that of R2 and R3 in . Preferred specific compounds of the acrylic esters included in component h-2 include trimethyl acrylate, trimethyl acrylate, trinoethyl dimethyl acrylate, diethylaminoethyl acrylate, and 3-dimethyl acrylate. ! knob 0jiru, acrylic acid
2-Dimethyla! A of acrylic acid such as Neusoprovir!
Examples include athrinal esters of methacrylic acid corresponding to noal I esters and second esters. An example of an acid addition salt of the above compound is 1jjJ! acid, sulfuric acid, cap L
Examples include water-soluble acid addition salts to which inorganic acids such as phosphoric acid or organic acids such as formic acid, acetic acid, prodiosic acid, and oxalic acid have been added.

Further, as the quaternary salt of the above compound, any ordinary quaternary salt obtained by known quaternization means can be used. Part 4
The quaternizing agent used in the quaternization may be the same as those used in the production of the quaternary salt of the compound of the general formula (1), and the quaternization reaction is also carried out in advance with the quaternizing agent of the formula [1]. The reaction may be carried out on the compound or its material, or it may be carried out on the portion corresponding to the compound of formula [1] in the copolymer after producing the copolymer.

The d component is a component that can be incorporated into the copolymer of the present invention as necessary, and specifically includes vinyl esters such as vinyl acetate, pro-vinyl osinate, styrene, Vinyl aromatic swelling hydrogens such as α-methylstyrene and vinyltoluene, α, β-unsaturated t-nocarboxylic acid nitriles such as acrylonitrile and methacrylonitrile, methyl acrylate, methyl methacrylate, ethyl acrylate, acrylic Acrylic acid or methacrylate l20 base prime number 1 to 8 alkyl esters, such as butyl acrylate, methyl methacrylate, and 2-ethyl acrylate.
In addition, there is also Methacrylic ΣF, Tiat Tocyacrylic!
Examples include 0, 0, etc.

The blending ratio of the above d component to d component is 1 to 20 mol% of the I component in the obtained copolymer, preferably 2 to 8 Yyl%,
component 1 to 20 mol%, preferably 2 to 155 mol%, C component 40 to 987 mol%, preferably 65 to 967 mol%, and d.
The range includes 0 to 305 types of components. If the amount of the four components is less than ttL%, the resulting copolymer will be close to a cationic polymer, and conversely, if the - component is less than ltL%, the resulting copolymer will be similar to an aniositic polymer and have fk series. In either case, it is difficult to exhibit the characteristics as a zero paper strength agent as expected in the present invention, which is not preferable.

Above - If the ingredient is 20 and exceeds the longevity or the body ingredient is 2
If the temperature exceeds 0°C, the obtained copolymer will be excellent in paper formation even when used as a paper strength agent, and will be difficult to impart paper strength.
In addition, it is undesirable to reduce the redisintegrability of the horizontal paper. Furthermore, as a Kei component, 111E min 10~50℃
It is important to use the combination of % and k=2 components at 50 to 90°C. If the 6-1 component in the I component is less than the above 10°C, that is, if the b-2 component is more than 90%, no matter how much the - component is used within the range of 1 to 20°C, there will be no gain. The paper obtained using the copolymer obtained from this method has insufficient paper strength. On the other hand, when the k=1 component exceeds 50°C, that is, when the -2 component is less than 50%, the redisintegrability of the broken paper O is reduced. In addition, component d, which is used as necessary, is used in an amount of 30 mol or less on the premise that the resulting copolymer exhibits water solubility, but examples include vinyl ester, vinyl aromatic hydrogen swelling, acrylic acid, The content of the alkyl esters of methacrylic acid is usually preferably up to 207%.

The copolymerization reaction of the above-mentioned components 1 to d can be carried out by various conventionally known methods. For example, using 0.05 to 5% by weight of a water-soluble 5-cal generating catalyst such as hydrogen peroxide, potassium persulfate, ammonium persulfate, etc., based on the above-mentioned Komotsummer mixture;
In an aqueous medium, the concentration is 5 to 50% by weight, and 50 to 50% by weight.
It may be carried out under stirring at a temperature of 95° C. for 1 to 10 hours. At this time, various water-soluble chemicals such as sodium bicarbonate,
Similar to the conventional method, it is also possible to use a buffering agent such as primary or secondary sodium phosphate, a reducing agent such as dimethylamine or sodium thiosulfate, or a chain transfer agent such as isopropyl alcohol or furyl alcohol. It is.

In this way, a copolymer to be used as an active ingredient in the paper strength agent of the present invention can be obtained. The copolymer is an amphoteric polymer having a cationic group and an anionic group in its molecule based on the use of the above-mentioned components and components, and has excellent properties in a wide range of pH ranges from alkaline to acidic. It can exhibit the effect of increasing paper strength. A preferred copolymer has a llt of 10% by weight aqueous solution of 100-1. OOO,000t/j
(25℃), especially the above viscosity is 500-10
A copolymer of 0,000 ζ is most suitable as a paper strength agent. The viscosity of the above-mentioned copolymer affects its properties as a paper strength enhancer; the lower the viscosity, the lower its paper strength enhancing effect, and the higher the viscosity, the tendency for the paper to collapse. However, those outside the range of 100 to 1,000,000 C are less desirable due to restrictions on their use.

In using the paper strength agent of the present invention, conventionally known methods may be followed. That is, the paper strength agent of the present invention is added to an aqueous pulp dispersion in an amount of 0.05 to 3% by weight based on the dry weight of the pulp, and papermaking is carried out with or without using sulfuric acid.

The type of pulp is not particularly limited, and ground pulp, sulfide pulp, trichemical pulp, kraft pulp, disintegrated waste paper, etc. can be used, and these are usually used as an aqueous dispersion of about 1 to 5% by weight. be done.

Before making the paper, add a sizing agent, such as reinforced 0jin soap, reinforced Qw, Shiemal Joshi, Arushi Luketene, in the same way as before.
The color can be changed by adding fillers such as mer emulsion, wax emul W53, alkenyl succinic acid soap, alkenyl succinic anhydride emulsion, etc., and fillers such as phosphorus, talc, titanium oxide, calcium suboxide, etc. The amount of these additives to be used may be appropriately determined depending on the type of additive and the purpose of the paper, but it is usually 0.05 to 3% by weight of the sizing agent and/or based on the dry weight of the pulp. 5-5
0% by weight 0 filler can be used.

Furthermore, in the present invention, paper broadly includes both ordinary paper and paperboard.

Production examples and usage examples (test examples) of the present invention and comparative paper strength agents are listed below.

Production Example 1 Acrylic anide 75.8F, dimethylaminoethyl methacrylate 19.7F, and acrylic acid 4.51.98F in a four-way flask equipped with a stirrer, thermometer, and nitrogen gas inlet tube.
% sulfuric acid, 4.2 f of a 48 eucaustic sorter, and 565 f of deionized water were charged, and the temperature was raised to 50° C. while stirring and introducing nitrogen gas. Next, 0.17 f of sodium persulfate and 0.04 f of acidic sulfite sodium were added, and the temperature was raised to 90°C (due to heat of polymerization). The polymerization reaction was completed by keeping at the same temperature for 3 hours, and then diluted by adding 333f of deionized water to obtain a mixture with a non-volatile content of 10% and a viscosity of Jt6300t.
An amphoteric copolymer aqueous solution of p z (25° C.) and fi H4,4 was obtained. This is referred to as paper strength agent A (comparison A).

Production Examples 2 to 11 A copolymer having the properties listed in Table 2 was prepared in the same manner as in Production Example 1 above, except that the types and amounts of components a to d were changed to those shown in Table 1. Aqueous solution (paper strength enhancer 16B~
K) was obtained. In each table, the paper strength agent obtained in Production Example 1 is also listed.

The abbreviations for each component in Table 1 indicate the following.

AA --- MAA acrylate --- Methacrylic acid b-11 --- N-(3-dimethylaminoprodyl)
Acryl anide b-12...N-(3-'; Methyl chloride 0 j-13...Trimethyl (3-acrylic chloride 0)
Dimethyl) ammonium chloride j-21-' -dimethylaminoethyl methacrylate b-22...diethylaminoethyl methacrylate h-23...trimethyl methacrylate ↑ diethylane and dimethylaminoethyl methacrylate AM... Acryl anide IN...Acrylic nitrile Table 2 Production example 12 Acryl anide 9'3.8 f, 80% acrylic acid aqueous solution 6.31% 48% in a Yotsurokolbene equipped with a stirrer, temperature needle, and diatomic gas inlet tube Prepared with caustic saw (4,6F and deionized 5601, stirred and heated at 45℃ while introducing methane gas.
0.18 f
When the anhydrous heavy M value acid sorter 0.08 F was added, the polymerization reaction started immediately and the internal temperature reached 90°C. After that, keep it at the same temperature for 3 hours to complete the polymerization reaction, and then add 3 mL of deionized water.
33f to make an aqueous copolymer solution with a non-volatile content of IO% (
A viscosity of 10,000 and a temperature of 5,125° C. were obtained.

Add to this 4896 caustic sorter 1.5F, 50% dimethyl acetate! ::I aqueous solution 18.8 F and 3796 formalin 1
Add 1.4f and react at 45℃ for 1 hour. Dilute with ionized water, non-volatile content 10g6, door H9.8, viscosity 4.
400 to obtain an aqueous copolymer solution (25°C). This is referred to as paper strength agent L (comparison L).

Production Example 13 200 ff of 104 water bath solution of polyacrylanid (average molecular weight 700,000): cooled to 15°C, and consisting of 18.6 ff of 1296 sodium hypochlorite aqueous solution, 4.61 ml of 4896 caustic soda and deionized water. Mixed liquid 160f was added dropwise over 30 minutes and held for an additional hour. During this time, keep the liquid temperature at 20℃. Then, the temperature was adjusted to 4.5 with hydrochloric acid, and the amphoteric acrylic trifluoride polymer containing 9.5% amino groups (-NH2) and 3.2°C. <viscosity 150 tfil, 25°C) was obtained. This is referred to as paper strength agent I (comparison M).

Test example l A paper strength agent was added to a 1% aqueous slurry of pulp (L-BKP, freeness 500dC5F) at a concentration of 0.3%, 0.5%, and 0.7% (in terms of non-volatile content, the same applies hereinafter). each amount, and then add sulfuric acid per 1* pulp,
Basis weight 5 using cod and standart sheet machine
Paper was made so that the ratio was 0±11/wl. Next, add 7# wet paper.
After compression dehydration for 5 minutes at /d and drying for 1 minute at 100°C, the resulting paper stock was conditioned for 24 hours at 20°C and 696R, II. The internal strength and redisintegration properties of this paper stock were tested using the following methods.
rnal bend 1etter, T-Totoi RC308, manufactured by Kumagai Riki ■.

Re-disintegration property: Using a disintegration machine (manufactured by Yasuda Seiso ■),
Measure the time (minutes) until disintegration is completed based on P-8209.

The results obtained using each paper strength agent are calculated using the amount of paper strength agent used (0,
3, 0, 5, and 0.7) are shown in Tables 3 to 5 below.

Table 3 (Using 0.3% paper strength agent) Table 4 (Using 0.5% paper strength agent) Table 5 (Using 0.7* paper strength agent) The results of Tables 3 to 5 above are particularly , paper strength agents A to E% From the comparison between paper strength agents F-I and paper strength agents 1- and paper strength agents RI and M, the known paper strength agents RI and I have extremely poor redisintegration properties;
This is further reduced due to the improvement of paper strength, whereas the paper strength agent of the present invention has improved redisintegration property and has an extremely excellent paper strength effect. The above-mentioned effects seen in the strength agent are based on the combination of the h-1 component and the b-2 component in a predetermined ratio, and are due to the use of the '-superacid component alone (without the h-2 component). (Comparison E) or when component b-2 is used in combination but in a smaller amount outside the scope of the present invention (comparison P%H and x>h
, respectively, are good in paper strength effect to some extent, similar to the well-known paper strength agent M, but redisintegration property is low. When the reverse Kh-2 component is used alone (without the j-1 component) (comparisons A, ! and I), it is clear that the paper strength itself is too low.

The above-mentioned excellent effects unique to the present invention are obtained by using each paper strength agent according to the above test examples, and achieving the same paper strength (internal strength 3.OO#・ex
a) It is even clearer from the results shown in Table 6 below, which calculate the amount of each paper strength agent added and the redisintegration properties of the paper at that time.

Table 6 Table 6 shows paper strength agents of the present invention (paper strength agents B and C).

G and J) are similar body components Cb-1 component alone, -12
Compared to the case where the components are used alone or in combination at a ratio outside the range of the present invention, paper having the same paper strength can be produced with a much smaller amount of addition (relative to pulp), and it is possible to produce paper with the same paper strength. It can be seen that the redisaggregation properties of the two are equivalent or even better. Furthermore, it is clear that the redisintegration property obtained by using the paper strength agent of the present invention is improved by more than 60% compared to conventional paper strength agents (Paper Strength Agent Shiri and M).

(that's all)

Claims (1)

[Claims] 0g) α,β-unsaturated t-nocarboxylic acid and/or
The alkaline salt is 1 to 20°C 1%, b) General formula [The middle layer in the formula is 2.3 or 4, R□ represents a hydrogen atom or a methyl group. 9 R2 and R3 are respectively the same or different and represent an alkyl group having 1 to 4 carbon atoms, or together with the nitrogen atom to which they are bonded, represent a 6-membered heterocyclic group] At least one cationic 7-mer (j-1
)010 to 50° C. and the general formula [The middle layer in the formula is 2.3 or 4, and R4 represents a hydrogen atom or a methyl group. R5 and R6 each represent an alkyl group having 1 to 4 carbon atoms, or a 6-membered heterocyclic group together with the nitrogen atom to which they are bonded. At least one cationic heptamine selected from acid esters, acid addition salts thereof, and quaternary salts thereof (''-2)
1-20% mixture with 050-901ext%, C) Acrylic acid 40-98°C %, and d) Above I
)~4-) and other nonionic ℃ temperature copolymerizable with -0~
An amphoteric paper strength agent characterized in that the blind component is a water-soluble copolymer having a composition of 50 tL%.