JP3259516B2 - Antifoaming agent for pulp black liquor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an antifoaming agent for pulp black liquor.

[0002]

2. Description of the Related Art Silicone antifoaming agents have various excellent properties as compared with other antifoaming agents.
Widely used in industrial processes involving foaming, such as the textile and pharmaceutical industries. For example, an oil compound-type defoamer in which silicone oil such as dimethylpolysiloxane, methylphenylpolysiloxane, and methylvinylpolysiloxane is mixed with finely divided silica. Emulsion-type defoamers obtained by dispersing these oil compounds together with a surfactant in water are widely used. Furthermore, the emulsion type antifoaming agent has a problem that the emulsion is destroyed under severe conditions such as high temperature, high alkalinity and high shearing force, and the defoaming ability is reduced. Are self-emulsifying defoamers using an organopolysiloxane modified with a polyoxyalkylene group and an oil compound (Japanese Patent Publication Nos. 52-19836, 52-22638 and 52-22638).
No. 5-23084).

[0003] However, these silicone-based antifoaming agents have the drawback that when they are added to a high-temperature, highly alkaline foaming liquid such as pulp black liquor, the defoaming property is lost over time.

In recent years, various devices have been devised for the purpose of improving the above-mentioned disadvantages and improving the defoaming performance.
For example, a method in which silica used in an oil compound is treated in advance with dimethyldichlorosilane or the like to make it hydrophobic (see Japanese Patent Publication No. 52-31836), or a method in which silica is treated with a nitrogen-containing organic silicon compound (Japanese Patent Publication No. 51-35)
556) is proposed. However, the above method requires a long time for the hydrophobizing treatment of silica, requires processing equipment, requires complicated steps, and is economically disadvantageous.

Japanese Patent Application Laid-Open No. 57-48307 proposes an organopolysiloxane or a hydrocarbon oil to which an organohydrogenpolysiloxane, silica and a catalyst have been added. If the heat treatment is not performed after the addition, the surface treatment of the silica does not proceed sufficiently, and there is a risk of ignition explosion due to hydrogen gas generated during the treatment process. Further, a method of mixing a crosslinked product of an organopolysiloxane with a mixture of an organopolysiloxane and silica (see JP-A-3-188905) has been proposed, but this method requires various steps. Therefore, it takes a long time for production, and it has a disadvantage that it is difficult to obtain good dispersibility at the time of dilution due to its high viscosity.

On the other hand, the present inventor has previously proposed a foam inhibitor composition using an oil compound in which an organosilicon compound having an alkenyl group is used as a silica treating agent for the purpose of improving the defoaming property of the self-emulsifier (Japanese Patent Laid-Open No. Hei. No. 91813),
A foam inhibitor composition (see JP-A-4-93453) in which a siloxane resin composed of (CH ₃ ) ₃ SiO _1/2 units and SiO _4/2 units is blended in an oil compound has been proposed. Improvement is required.

The present invention has been made in view of the above circumstances, and has an excellent defoaming effect and sustainability even under high temperature and high alkalinity conditions, and can be industrially advantageously produced in an antifoaming agent for pulp black liquor. The purpose is to provide.

[0008]

The present inventors have conducted intensive studies to achieve the above object, and as a result, the amine equivalent represented by the following average composition formula (1) was 500 to 10,000.
An organopolysiloxane composition comprising an aminoalkyl-modified silicone oil having a viscosity at 0 and 25 ° C. of 10 to 100000 cs and finely divided silica; and a compound having a viscosity at 25 ° C. represented by the following average composition formula (2) of 1
A polyoxyalkylene-modified silicone oil having a molecular weight of 500 to 50
When blended with a polyoxyalkylene polymer of 00,
An excellent self-emulsifying type foam inhibitor composition which can continuously exhibit an excellent defoaming effect even under high temperature and high alkalinity conditions is obtained, and this foam inhibitor composition is a pulp black liquor. It has been found that it is suitable as a main component of an antifoaming agent.

[0009]

Embedded image Wherein R ¹ is —R ⁴ (NR ⁵ CH ₂ CH ₂ ) _m NR ⁶ R ⁷
(R ⁴ is a divalent hydrocarbon group having 1 to ⁴ carbon atoms, R ⁵ , R ⁶ ,
R ⁷ is a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, and m is a number satisfying 0 ≦ m ≦ 4. R ² is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, R ³ is —OR ⁸ (R ⁸ is a hydrogen atom or a carbon atom having 1 to 6 carbon atoms) The alkoxy group represented by a monovalent hydrocarbon group), a, b, and c are 0.0001 ≦ a ≦ 1, 1.8 ≦ b ≦ 2.2, and 0 ≦ c ≦, respectively.
0.1 is a number that satisfies 1.8 <a + b + c <2.3. ]

[0010]

Embedded image [However, wherein R ⁹ is ^{-R 11 -0 (R 12 O)} f -R 13 (R 11
Is a divalent hydrocarbon group having 1 to 4 carbon atoms, R ¹² is an ethylene group and / or a propylene group, and R ¹³ is a hydrogen atom or 1 to 4 carbon atoms.
8 unsubstituted or substituted monovalent organic groups, f is 3 ≦ f ≦ 10
Number of 0. R ¹⁰ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, and d and e are 0.01 ≦ d ≦ 1, 1.2, respectively.
It is a number that satisfies 1.8 <d + e <2.3 when ≦ e ≦ 2.2. ]

That is, the present inventors have developed an aminoalkyl-modified foam having a specific amine equivalent of the above formula (1) as a base oil of an oil compound component composed of a base oil and finely divided silica in a self-emulsifying type foam inhibitor composition. By using silicone oil, a high-temperature, highly defoaming effect even for a highly alkaline foaming liquid and a foam suppressing agent composition showing its persistence can be obtained. The present inventors have found that they can be easily produced in simple steps by simple mixing of the respective components described above, and that they are satisfactory in terms of economy and safety, and have accomplished the present invention.

Accordingly, the present invention provides: (A) an amine equivalent represented by the above average composition formula (1) of 5
00-100,000, viscosity at 25 ° C is 10-10
1 to 60% by weight of an organopolysiloxane composition containing an aminoalkyl-modified silicone oil of 0000 cs and finely divided silica; and (B) a viscosity at 25 ° C. of 10 to 100000 cs represented by the above average composition formula (2). A pulp containing, as a main component, a foam inhibitor composition comprising 5 to 99% by weight of a polyoxyalkylene-modified silicone oil which is a polyoxyalkylene polymer having a molecular weight of 500 to 5,000. Provide an antifoaming agent for black liquor.

Now, the present invention will be described in further detail. The organopolysiloxane composition of the first component constituting the foam inhibitor composition of the present invention has an amine equivalent represented by the following average composition formula (1) of 500 It contains an aminoalkyl-modified silicone oil having a viscosity of 10 to 100,000 cs at 100 ° C. and 25 ° C. and finely divided silica, and is a main component of the foam inhibitor composition.

[0014]

Embedded image Wherein R ¹ is —R ⁴ (NR ⁵ CH ₂ CH ₂ ) _m NR ⁶ R ⁷
(R ⁴ is a divalent hydrocarbon group having 1 to ⁴ carbon atoms, R ⁵ , R ⁶ ,
R ⁷ is a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, and m is a number satisfying 0 ≦ m ≦ 4. R ² is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, R ³ is —OR ⁸ (R ⁸ is a hydrogen atom or a carbon atom having 1 to 6 carbon atoms) The alkoxy group represented by a monovalent hydrocarbon group), a, b, and c are 0.0001 ≦ a ≦ 1, 1.8 ≦ b ≦ 2.2, and 0 ≦ c ≦, respectively.
0.1 is a number that satisfies 1.8 <a + b + c <2.3. ]

In the above formula (1), the substituent R ¹ is -R ⁴
(NR ⁵ CH ₂ CH ₂ ) _m NR ⁶ R ⁷ . Here, R ⁴ is a divalent hydrocarbon group having 1 to 4 carbon atoms such as a methylene group, an ethylene group, a propylene group, and a butylene group. R ⁵ , R ⁶ , R
⁷ is each a hydrogen atom or, for example, a methyl group, an ethyl group,
Propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, dodecyl group, tetradecyl group, hexadecyl group, alkyl group such as octadecyl group, vinyl group, alkenyl group such as allyl group, A phenyl group, an aryl group such as a tolyl group, a cycloalkyl group such as a cyclohexyl group, a part or all of the hydrogen atoms bonded to carbon atoms of these groups are halogen atoms,
Same or different carbon number selected from halogen substitution such as chloromethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group, cyanoethyl group and the like, and cyano group-substituted hydrocarbon group substituted by a cyano group and the like. is a 1-18 unsubstituted or substituted monovalent hydrocarbon group, R ^5, R ^6, preferably, at least 90 mole percent of the whole group of R ⁷ is a hydrogen atom. Note that m is a number satisfying 0 ≦ m ≦ 4.

R ² represents, for example, methyl, ethyl, propyl, butyl, pentyl, hexyl,
Alkyl group such as heptyl group, octyl group, nonyl group, decyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group, alkenyl group such as vinyl group and allyl group, aryl group such as phenyl group and tolyl group, cyclohexyl group Cycloalkyl groups such as, a part or all of the hydrogen atoms bonded to carbon atoms of these groups are halogen atoms,
Same or different carbon number selected from halogen substitution such as chloromethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group, cyanoethyl group and the like, and cyano group-substituted hydrocarbon group substituted by a cyano group and the like. is a 1-18 unsubstituted or substituted monovalent hydrocarbon group, the total R ² groups 90
Preferably, at least mol% is a methyl group.

R ³ in the above formula (1) includes a hydroxyl group or an alkoxy group represented by —OR ⁸ . In this case, R
⁸ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms, and examples of the monovalent hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. Particularly, a methyl group is preferable.

A, b and c are each 0.0001 ≦ a ≦
1, 1.8 ≦ b ≦ 2.2, 0 ≦ c ≦ 0.1 and 1.8 <a
+ B + c <2.3, but particularly from the viewpoint of defoaming property, 0.001 ≦ a ≦ 0.5, 1.9 ≦ b ≦ 2.1, 0
It is preferable that 1.9 <a + b + c <2.2 when ≤c≤0.05.

The aminoalkyl-modified silicone of the above formula (1) is preferably linear, but may be branched.

The amine equivalent of the aminoalkyl-modified silicone of the above formula (1) ranges from 500 to 100,000, preferably from 1,000 to 10,000, and the amine equivalent is 5
If it is less than 00 or more than 100,000, the dilution stability of the composition is deteriorated, and the defoaming effect is reduced.

The aminoalkyl-modified silicone of the above formula (1) preferably has a viscosity as low as possible from the viewpoints of easy dispersibility and workability, and has a higher viscosity from the viewpoint of sustainability of defoaming. Considering that the viscosity is good, the viscosity at 25 ° C. is 10 to 100000 cs, preferably 10
The range is from 0 to 20000 cs. If the viscosity is less than 10 cs, the composition becomes poor in stability and 100,000 c
If it exceeds s, the workability in diluting the obtained composition becomes difficult.

Further, known fine powdered silica may be used, and may be either wet silica or dry silica. For example, precipitated silica, silica xerogel, fumed silica, and the surface thereof are treated with an organic silyl group. Specific examples include Aerosil (manufactured by Nippon Aerosil Co., Ltd.), Nipsil (manufactured by Nippon Silica Co., Ltd.), Cabosil (manufactured by Cabot Corporation, USA), and Santocell (manufactured by Monsanto Chemical Company, USA). The fine powder silica preferably has a specific surface area by BET method of 100 m ² / g or more.

The amount of the finely divided silica is 0.1 to 20 parts, preferably 1 to 10 parts, per 100 parts (parts by weight, hereinafter the same) of the aminoalkyl-modified silicone oil of the above formula (1).
It is preferable to use a part. If the amount is less than 0.1 part, the defoaming performance may be inferior. If the amount exceeds 20 parts, the viscosity of the composition may increase and the water dispersibility and workability may deteriorate.

The organopolysiloxane composition of the first component is prepared by blending a predetermined amount of the above-mentioned aminoalkyl-modified silicone oil and finely divided silica and heat-treating the mixture at room temperature to 200 ° C. for 1 to 3 hours. It can be manufactured by removing the minute. In addition, at the time of this heat treatment, an organosilazane compound, a silane coupling agent, and the like can be added and blended as necessary to achieve uniformity.

The amount of the organopolysiloxane composition of the first component is preferably in the range of 1 to 60% (% by weight, hereinafter the same), especially 5 to 40% of the whole composition of the present invention.
If the amount is less than 1%, the foam-suppressing effect may not be sufficiently obtained, and if it exceeds 60%, the viscosity may be high and the dispersibility in water may be poor, making it difficult to handle.

Next, the polyoxyalkylene-modified silicone oil as the second component of the present invention is represented by the following average composition formula (2), and the foam inhibitor composition of the present invention is added to an aqueous foaming liquid. In doing so, it acts as an emulsifier for emulsifying and dispersing the organopolysiloxane composition of the first component.

[0027]

Embedded image [However, wherein R ⁹ is ^{-R 11 -0 (R 12 O)} f -R 13 (R 11
Is a divalent hydrocarbon group having 1 to 4 carbon atoms, R ¹² is an ethylene group and / or a propylene group, and R ¹³ is a hydrogen atom or 1 to 4 carbon atoms.
8 unsubstituted or substituted monovalent organic groups, f is 3 ≦ f ≦ 10
Number of 0. R ¹⁰ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, and d and e are 0.01 ≦ d ≦ 1, 1.2, respectively.
It is a number that satisfies 1.8 <d + e <2.3 when ≦ e ≦ 2.2. ]

[0028] R ⁹ in the formula (2) is -R ¹¹ -0
Is a polyoxyalkylene group represented by _{^{(R 12 O) f -R 13}} . Here, R ¹¹ is a divalent hydrocarbon group having 1 to 4 carbon atoms such as a methylene group, an ethylene group, a propylene group, and a butylene group. R ¹² is an ethylene group and / or a propylene group,
R ¹³ is a hydrogen atom or an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group; an acetyl group; Monovalent organic group, f is 3 ≦ f
<100.

R ¹⁰ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, and examples thereof include the same groups as those described above for R ² . d and e are respectively 0.01 ≦ d ≦ 1,
It is a number that satisfies 1.8 <d + e <2.3 when 1.2 ≦ e ≦ 2.2.

The polyoxyalkylene-modified silicone oil of the above formula (2) is preferably liquid at room temperature, and has a viscosity at 25 ° C. of from 10 to 100,000 cs, preferably from 100 to 10,000 cs. When the viscosity is less than 10 cs, the composition is easily separated and the stability is low. When the viscosity is more than 100,000 cs, the composition is difficult to disperse and is inferior in workability when diluted with water before use.

As the polyoxyalkylene-modified silicone oil of the above formula (2), a commercially available polyether-modified silicone oil may be used, or a conventionally known method, for example, an organopolysiloxane containing a ≡SiH group A compound which can be easily obtained by subjecting a polyoxyalkylene compound having an unsaturated group such as a vinyl group or an allyl group at the molecular chain terminal to an addition reaction in the presence of a platinum catalyst may be used. In the present invention, not only a silicone oil modified with a single polyoxyalkylene compound but also, for example, two or more polyoxyalkylene groups having different molar ratios of ethyleneoxy groups / propyleneoxy groups in the molecule can be used in the same molecule. The silicone oil contained therein can be used, and it is also possible to use two or more kinds of polyoxyalkylene-modified silicone oils having different structures.

The compounding amount of the polyoxyalkylene-modified silicone oil of the above formula (2) is 5 to 99% of the total composition.
%, Particularly 10 to 80% is suitable. If it is less than 5%, the water dispersibility may be poor, and if it exceeds 99%, the defoaming property may be poor.

Further, in the present invention, it is preferable to blend a polyoxyalkylene polymer as the third component. This polyoxyalkylene polymer acts as an emulsifying aid together with the polyoxyalkylene-modified silicone oil of the second component, and also has the effect of reducing the viscosity of the composition and improving the workability during water dispersion. is there.

The polyoxyalkylene polymer may have any structure as long as it has a (R ¹⁴ O) group (R ¹⁴ is an ethylene group and / or a propylene group) in the molecule, and may have a linear structure. For example, it may be branched as in the following structure.

[0035]

Embedded image (Where R ¹⁵ is a hydrogen atom or a monovalent organic group,
R ¹⁶ is a monovalent alkyl group. q, r, and s are each independently 1 to 100. )

The terminal group R ¹⁵ of the polymer is a hydrogen atom or an alkyl group such as a methyl group, an ethyl group, a butyl group, a decyl group or an octadecyl group, an alkenyl group such as a vinyl group, an allyl group or an oleyl group, or an acetyl group. In general, a monovalent organic group having 1 to 18 carbon atoms such as an acyl group such as a stearoyl group or an isocyanic acid group is not limited thereto. R ¹⁶ is a monovalent alkyl group, for example, those having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, and a butyl group.

The polyoxyalkylene polymer is preferably liquid at room temperature and has an average molecular weight of 500 to 500.
A value of 0, especially 1000 to 3000 is preferred. If the average molecular weight is less than 500, the resulting foam suppressant composition may have poor stability over time due to low viscosity.
If it exceeds 000, the viscosity may be increased and the dispersibility and workability may be affected.

The polyoxyalkylene polymer as the third component is not limited to the use of one kind of polyoxyalkylene compound alone, but may be a combination of two or more kinds of polyoxyalkylene compounds having different HLB values and terminal groups. You may.

The compounding amount of the polyoxyalkylene polymer is as follows:
It is preferably from 0 to 90%, especially from 0 to 70% of the whole composition. If the amount exceeds 90%, the storage stability and the dilution stability of the composition may be deteriorated.

In the present invention, the weight ratio of ethyleneoxy group / propyleneoxy group in the second and third components is desirably in the range of 0.1 to 5, particularly 0.4 to 3, It is desirable to select the compounds of the second and ternary components and adjust the blending amount so as to fall within the range. When the ethyleneoxy group / propyleneoxy group ratio is less than 0.1, the hydrophobicity becomes strong, and when it exceeds 5, the HLB value becomes too large, and in any case, the function as an emulsifier may not be sufficiently exhibited.

The foam inhibitor composition of the present invention can be obtained by mixing predetermined amounts of the above-mentioned components, and these components can be uniformly mixed using a mixer such as a homomixer. preferable. The order of mixing the components is not particularly limited, and the mixing conditions are not particularly limited.
It is preferable to mix while heating in the range of 40 to 150 ° C. if necessary.

Further, when preparing as a defoamer for pulp black liquor, the foam inhibitor composition of the present invention may be blended as a main component, and mineral oil or the like may be added as another component.

[0043]

The foam inhibitor composition of the present invention is excellent in defoaming effect and its sustainability even under high temperature and high alkalinity conditions, and is easily and economically advantageous in a simple process and safe. Can be obtained. Therefore, the composition of the present invention can be effectively used for pulp black liquor.

[0044]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Production Examples, Examples, and Comparative Examples, but the present invention is not limited to the following Examples. In addition, the viscosity in each example shows the measured value at 25 degreeC.

[Production Example 1] X_0.0196(CH_Three)_1.98(OCH_Three)_0.0098SiO _0.995 (Where X is -C_ThreeH₆NHCH_TwoCH_TwoNH_TwoIn
You. The same applies hereinafter. ) Amine equivalent 1900, viscosity 1900c represented by the above formula
285 g of aminoalkyl-modified silicone oil
Nippon Aerosil 300 (Nippon Aerosil)
Made by Le, 300m^Two/ G) 15 g, hexamethyl
9 g of rudisilazane in a 500 cc flask with nitrogen gas
Heat treated at 150 ° C for 3 hours under air current, and mix with homomixer
To prepare an organopolysiloxane composition A.
Was.

[Production Example 2] X_0.0049(CH_Three)_2.00SiO _0.998 As shown above, it is an aminoalkyl-modified silicone oil.
With an amine equivalent of 7600 and a viscosity of 250 cs
Except for using 285 g of rutile-modified silicone oil
Organopolysiloxane composition B as in Production Example 1
Was prepared.

[Production Example 3] Y_0.0078(CH_Three)_1.99(OCH_Three)_0.00519SiO _0.999 (Where Y is -C_ThreeH₆NH_TwoIt is. Below,
Mr. ) Aminoalkyl-modified silicone oil represented by the above formula
Amine having an equivalent weight of 9400 and a viscosity of 15800 cs
Use 285 g of a noalkyl-modified silicone oil
Except for the organopolysiloxane composition as in Production Example 1,
Preparation C was prepared.

[Production Example 4] X_0.118(CH_Three)_1.94SiO _0.971 An amine having an amine equivalent of 360 and a viscosity of 60 cs represented by the above formula
285 g of minoalkyl modified silicone oil and fine powder
Nipsil SS-30P as Rica (Nippon Silica Industry Co., Ltd.)
Made, specific surface area 114m^Two/ G) 15g to 500cc
Heat treatment at 150 ° C for 3 hours under nitrogen gas flow in Lasco
And mix and stir with a homomixer.
A composition D was prepared.

[Production Example 5]_0.000595(CH_Three)_2.01SiO _0.995 As shown above, it is an aminoalkyl-modified silicone oil.
Amine having an equivalent weight of 150,000 and a viscosity of 800 cs
Use 285 g of a noalkyl-modified silicone oil
Except for the organopolysiloxane composition as in Production Example 4,
Preparation E was prepared.

[Production Example 6] (CH_Three)_2.01SiO _0.995 The above formula replaces the aminoalkyl-modified silicone oil
Dimethyl silicone oil having a viscosity of 1000 cs
Except that 285 g of toluene were used.
Ganopolysiloxane composition F was prepared.

Example 1 100 g of the organopolysiloxane composition A obtained in Production Example 1 and 60 g of a polyoxyalkylene-modified silicone oil A having a viscosity of 1400 cs represented by the following composition formula (3) were prepared according to the following composition formula (4). Polyoxyethylene-polyoxypropylene copolymer A220 having an average molecular weight of 2030 and a viscosity of 200 cs shown
g, the average molecular weight represented by the following composition formula (5) is 145
4. 120 g of polyoxyethylene-polyoxypropylene copolymer B having a viscosity of 150 cs was mixed and stirred with a homomixer for 10 minutes to prepare a foam inhibitor composition A. ^{_{G 1 0.1 (CH 3) 2.0}} SiO 0.95 ... (3) (G 1 is _{-C 3 H 6 O (C 2} H 4 O) 25 (C 3 H 6 O) 25 C 4 H
_{9) C 4 H 9 O (} C 2 H 4 O) 30 (C 3 H 6 O) 10 C 4 H 9 ... (4) C 4 H 9 O (C 2 H 4 O) 5 (C 3 H 6 O ) ₂₀ H ... (5)

Examples 2 and 3 and Comparative Examples 1 to 3 The same procedures as in Example 1 were carried out except that organopolysiloxane compositions B to F were used instead of organopolysiloxane composition A as shown in Table 1. In the same manner, foam inhibitor compositions BF were prepared.

Example 4 150 g of the organopolysiloxane composition A, 260 g of the polyoxyalkylene-modified silicone oil A used in Example 1, and the following composition formula (6)
Was mixed with 90 g of a polyoxyalkylene-modified silicone oil B having a viscosity of 1100 cs, and stirred with a homomixer for 10 minutes to prepare a foam inhibitor composition A '. ^{_{G 2 0.03 (CH 3) 1.98}} (C 10 H 21) 0.03 SiO 0.98 ... (6) (G 2 is _{-C 3 H 6 O (C 2} H 4 O) 6 (C 3 H 6 O) 24 H)

Examples 5 and 6, Comparative Examples 4 and 6 The same as Example 4 except that organopolysiloxane compositions BF were used instead of organopolysiloxane composition A as shown in Table 1. And foam suppressor compositions B ′ to F ′
Was prepared.

The defoaming property of the above foam inhibitor composition to pulp black liquor was examined by the following method. Table 1 shows the results. Defoaming test method using pulp black liquor: 50 g of pulp black liquor having a pH of 13.0 was placed in a 100 cc glass bottle capable of being stoppered.
After leaving in a thermostat at 0 ° C. for 30 minutes, 100 ppm of the foam inhibitor composition was immediately added thereto, and the mixture was shaken for 30 seconds (140 times / minute), and the time (second) until the generated bubbles completely disappeared was measured. did. Immediately after the measurement, the glass bottle was returned to the 80 ° C. constant temperature bath, and after 1 hour and 24 hours, the same shaking was performed for 30 seconds in the same manner as described above, and the time required for the generated bubbles to completely disappear was determined. It was measured.

From the results shown in Table 1, it can be seen that the foam suppressant composition of the present invention (Example) is excellent not only in the foam suppressing property immediately after being blended into the foaming liquid but also in the foam suppressing liquid after heating. It turned out that it was extremely excellent in durability.

[0057]

[Table 1]

────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Satoshi Kuwata 1-10 Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture Inside the Silicone Electronics Materials Research Laboratory, Shin-Etsu Chemical Co., Ltd. (56) References JP-A-5-285306 ( JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B01D 19/04 D21C 11/10

Claims (1)

(57) [Claims] (A) An aminoalkyl-modified silicone oil represented by the following average composition formula (1) having an amine equivalent of 500 to 100,000 and a viscosity at 25 ° C. of 10 to 100,000 cs, and finely divided silica. 1 to 60% by weight of an organopolysiloxane composition, Wherein R ¹ is —R ⁴ (NR ⁵ CH ₂ CH ₂ ) _m NR ⁶ R ⁷
(R ⁴ is a divalent hydrocarbon group having 1 to ⁴ carbon atoms, R ⁵ , R ⁶ ,
R ⁷ is a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, and m is a number satisfying 0 ≦ m ≦ 4. R ² is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, R ³ is —OR ⁸ (R ⁸ is a hydrogen atom or a carbon atom having 1 to 6 carbon atoms) The alkoxy group represented by monovalent hydrocarbon group), a, b, and c are respectively 0.0001 ≦ a ≦ 1, 1.8 ≦ b ≦ 2.2, and 0 ≦ c ≦
0.1 is a number that satisfies 1.8 <a + b + c <2.3. (B) 5 to 99% by weight of a polyoxyalkylene-modified silicone oil having a viscosity at 25 ° C. of 10 to 100000 cs represented by the following average composition formula (2): Wherein R ⁹ is —R ¹¹ —O (R ¹² O) _f —R ¹³ (R ¹¹
Is a divalent hydrocarbon group having 1 to 4 carbon atoms, R ¹² is an ethylene group and / or a propylene group, and R ¹³ is a hydrogen atom or 1 to 4 carbon atoms.
8 unsubstituted or substituted monovalent organic groups, f is 3 ≦ f ≦ 10
Number of 0. R ¹⁰ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms, and d and e are 0.01 ≦ d ≦ 1, 1.2, respectively.
It is a number that satisfies 1.8 <d + e <2.3 when ≦ e ≦ 2.2. (C) An antifoaming agent for pulp black liquor containing a foam inhibitor composition comprising, as a main component, 0 to 90% by weight of a polyoxyalkylene polymer having a molecular weight of 500 to 5,000.