JPS6411239B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a water and oil repellent with improved durability, and more specifically, to a water and oil repellent containing a polyfluoroalkyl group and an active hydrogen group, a blocked isocyanate compound with a specific structure is added. This invention relates to a novel water and oil repellent obtained by mixing. Prior Art Conventionally, acrylate or methacrylate homopolymers containing polyfluoroalkyl groups,
Alternatively, copolymers of these and other vinyl monomers such as alkyl acrylate, maleic anhydride, vinyl chloride, and styrene are known to exhibit excellent water and oil repellent effects, and are mainly used as repellents for textile treatment. It is widely used as a water and oil repellent. One of the major characteristics of this type of water and oil repellent is that it is relatively durable compared to conventional paraffin-based or ethylene urea-based water repellents, but with the recent trend towards high quality. Accordingly, further improvement in durability is desired. Therefore, as an attempt to improve durability, for example...
NHCH ₂ OR, ―COOCH ₂ CH ₂ OH,

[Formula] It is possible to copolymerize a monomer containing a functional group such as a polyfluoroalkyl group with a monomer containing a polyfluoroalkyl group, or to use a crosslinking agent such as a methylolmelamine resin or a bifunctional aziridine compound in combination with the water and oil repellent. However, the effects are not always satisfactory; on the other hand, the use of methylolmelamine resin results in a hard texture, and the use of aziridine compounds tends to cause skin disorders, among other secondary problems. . As another attempt, we added the following blocked isocyanate to fluororesin. Alternatively, a method of using C ₆ H ₅ OCONH (CH ₂ ) ₆ NHCOOC ₆ H ₅ in combination is also known (Japanese Unexamined Patent Application Publication No. 1986-
128991, 54-128992, 54-131579, 54-
133486 et al.). In this example it is very reactive;
Since blocked isocyanate, in which isocyanate groups that are susceptible to the action of moisture are masked with phenol, is used as a crosslinking agent, the treatment agent can be provided as an aqueous dispersion, and free isocyanate groups can be expressed by appropriate heating after fiber treatment. The process involves completing the crosslinking with the fluororesin, and it can be said to be a very logical and interesting method. Unfortunately, however, the blocked isocyanate compounds that have been tried so far have not been able to exhibit sufficient effects even when applied to fluorine-based water and oil repellents. In general, in the case of fluorine-based water and oil repellents, the degree of water and oil repellency depends on the degree of orientation of the polyfluoro groups on the fibers, and the durability depends on the degree of orientation of the polyfluoro groups on the fibers. This is due to the degree of damage or shedding caused by the friction of washing or wearing the film. In other words, the more orderly the polyfluoro groups are oriented on the fiber, the more excellent the water and oil repellency will be, and the more the water and oil repellent film will be oriented, the better the water and oil repellent effect will be. It can be said to be an excellent water and oil repellent. Therefore, to improve water and oil repellency, it is important to use a compound that improves the orientation of polyfluoro groups, and to improve durability, it is important to use a highly reactive crosslinking agent to improve the bond between fluorocarbon resins. It is important to complete crosslinking and obtain a stronger film. It would be ideal if a single compound had an effect of improving orientation and also had a crosslinking effect. It seems that the blocked isocyanate compounds that have been tried in the past have placed too much emphasis on the crosslinking effect and have not given sufficient consideration to improving orientation. Purpose of the Invention The present invention provides a water and oil repellent effect by adding and mixing a blocked isocyanate compound to a water and oil repellent containing a polyfluoroalkyl group and an active hydrogen group (hereinafter referred to as a fluorine-based water and oil repellent). The purpose of the present invention is to provide a water and oil repellent that is excellent in both properties and durability. Structure of the Invention The water and oil repellent of the present invention is obtained by adding and mixing a blocked isocyanate compound represented by the following general formula (I) to a fluorine-based water and oil repellent. (However, R ₁ and R ₂ each represent an alkyl group consisting of C _{1 to 4.} ) It is important that the fluorine-based water and oil repellent used in the present invention contains both a polyfluoroalkyl group and an active hydrogen group. It is. Such water and oil repellents include:
First, a copolymer of a polymerizable compound containing a polyfluoroalkyl group and a monomer having an active hydrogen group may be mentioned. (Of course, it may also be a polymer or copolymer of monomers containing both a polyfluoroalkyl group and an active hydrogen group.) Containing a polyfluoroalkyl group that can be a constituent unit of a copolymer type fluorine-based water and oil repellent agent Typical monomers include, for example,

【table】 /
CF ₃

[Table] Examples include, but usually the general formula CH ₂ = C (R ³ )
COO(R ⁵ ) _n Rf (where, Rf is a linear or branched polyfluoroalkyl group having 3 to 20 carbon atoms, R ³ is a hydrogen atom or a methyl group, and R ⁵ is a linear chain having 1 to 10 carbon atoms) It is preferable to use acrylate or methacrylate represented by a (branched or branched alkylene group, m represents 0 or 1), and in particular Rf has 6 to 6 carbon atoms.
12, preferably R has 2 to 4 carbon atoms and m is 1. In addition, as active hydrogen group-containing monomers copolymerized with these polyfluoroalkyl group-containing monomers, monomers having -OH, _-NH2 , -COOH, etc., such as _CH2 =C( ^R3 )COO-(AlK ―
O-) _o H (wherein R ³ is a hydrogen atom or a methyl group, Alk is a divalent alkylene group having 2 to 6 carbon atoms, and n is an integer of 0 or 1 to 50), CH ₂ =C
(R ³ )—CONH(A)NHR ⁴ (wherein, R ³ is a hydrogen atom or a methyl group, A is a divalent alkylene group or a phenylene group, R ⁴ is a hydrogen atom or an alkyl group), CH ₂ =C ( R ³ )CONH(A)OH (wherein R ³ is a hydrogen atom or a methyl group, and A is a divalent alkylene group or a phenylene group). Specific examples of active hydrogen group-containing monomers include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, and crotonic acid; alkylene oxide adducts of such unsaturated carboxylic acids, such as CH ₂
=C( ^CH3 )COO( _CH2CH2O ) _{1~ 2H} , _CH2 =
CHCOO( _CH2CH2O ) _1~ 2H, _{CH2 =} C( _CH3 )
COO( _CH2CH2O ) _{6~ 8H} , _CH2 =C( _CH3 )COO
(CH ₂ CH ₂ O) ₇ H, CH ₂ C (CH ₃ ) CO, O
( _CH2CH2O ) _{9H ,}

[Formula] etc.; OH group-containing acrylamides such as N-methylol acrylamide and N-ethanol acrylamide; NH group-containing acrylamides such as CH ₂ =CHCONHCH ₂ CH ₂ NH CH ₃ ; Copolymer type fluorine-based water and oil repellents may contain other monomers such as ethylene, vinyl acetate, vinyl chloride, vinylidene chloride, vinyl fluoride, acrylamide, methacrylamide, styrene, α-methylstyrene, p-methylstyrene. , alkyl esters of acrylic acid or methacrylic acid, benzyl acrylate or methacrylate, vinyl alkyl ethers, halogenated alkyl vinyl ethers,
Vinyl alkyl ketone, cyclohexyl acrylate or methacrylate, maleic anhydride, butadiene, isoprene, chloroprene, CH ₂ =C
(R′)COO−(Alk−O) _x −R″(However, Alk is C ₂ to C ₄
(x is an integer of 1 to 50, R', R'' is a hydrogen atom or a methyl group) may be further copolymerized.In addition, vinyl acetate etc. may be copolymerized with polyfluoroalkyl group-containing polyfluoroalkyl group. Active hydrogen groups (-
OH) and a polyfluoroalkyl group can also be used as a fluorine-based water and oil repellent. Furthermore, as fluorine-based water and oil repellents, Rf (R6) _n OCO-(Alk-O-) _o H, RfCONH−(Alk−O) _o −H RfSO ₂ N(R7)−(Alk−O) _o −H, Rf(R6) _n O−(Alk−O) _o −H (However, Rf in the formula is the number of carbon atoms. 3 to 20 linear or branched polyfluoroalkyl group, R7 is hydrogen or a lower alkyl group, R6 is a linear or branched alkylene group having 1 to 10 carbon atoms, m is 0 or 1, n is 0 to 50
(where Alk is an alkylene group having 2 to 6 carbon atoms), compounds containing both a polyfluoroalkyl group and an active hydrogen group in the molecule may also be employed. The fluorine-based water and oil repellent is prepared and used in any form such as an emulsion, a solvent solution, or an aerosol. Next, as the blocked isocyanate compound added to the fluorine-based water and oil repellent, any of the compounds represented by the above formula (1) can be used. It can be prepared by reacting moles and subsequently masking the free isocyanate groups with oximes. The blending ratio of the fluorine water and oil repellent to the blocked isocyanate compound in the present invention is not particularly limited, but is generally used in a weight ratio of 45:55 to 99:1. Particularly preferred range is 65:35-95:
5, and the most commonly used is 80:20-90:
In the range of 10. Articles that can be treated with the water and oil repellent of the present invention are mainly textile products, but are not necessarily limited thereto, and can also be applied to paper, leather, etc. Examples of textile products include natural fibers, synthetic fibers, semi-synthetic fibers, yarns made of one or more types of inorganic fibers, woven fabrics, knitted fabrics, non-woven fabrics, and processed products thereof, but especially those that react with isocyanate groups. The water and oil repellent of the present invention exhibits an outstanding durable effect on cellulose fiber products (including blended products, inter-knitted fabrics, inter-woven fabrics) that have an -OH group that is easy to remove. Next, examples of the present invention will be described in more detail, but it goes without saying that this description does not limit the present invention. The water repellency and oil repellency shown in the following examples are shown using the following scale. That is, water repellency is expressed by the water repellency No. (see Table 1 below) determined by the JIS-L-1005 spray method, and oil repellency is expressed by applying the test solution shown in Table 2 below on a sample cloth. Place several drops (approximately 1 mm in diameter) in the area and judge by the penetration state after 30 seconds (AATCC-TM
118−1966).

【table】

[Table] Also, the durability of the treated cloth is 1
After washing, washing, rinsing, and air drying for 10 minutes at 50°C in a washing bath with 60g of detergent (Super Zabu: product name) and a bath volume of 35kg, the water and oil repellency was measured. judge. In addition, all the compounding ratios of each component in an Example are shown by weight ratio. Example 1 A dropping funnel, a thermometer, a cooling pipe, and a stirring blade were installed, and the internal volume was 500 c.c., which was set on a water bath.
52.2 g (0.3 mol) of 2,4-toluylene diisocyanate, 13.4 g (0.1 mol) of trimethylolpropane, and 200 g of methyl ethyl ketone were placed in a four-necked flask, and the temperature of the liquid was raised to 70°C while stirring. for 2 hours, then 2-butanone oxime
26.1 g (0.3 mol) was added dropwise through a dropping funnel over 1 hour, and stirring was continued for an additional hour after the addition was completed. After distilling off the solvent methyl ethyl ketone from the reaction mixture using a vacuum evaporator, the residue was vacuum dried to obtain 90.7 g of a yellowish white solid.
Analysis of this solid by gas chromatography and infrared absorption spectroscopy revealed that it was the desired product. The selectivity was 93.5%, and the yield based on the raw material diisocyanate was 92.5% (the above compound is called TPDO). RfCH ₂ CH ₂ OCOCH=CH ₂ as water and oil repellent containing polyfluoroalkyl group and active hydrogen group
(1/3/2/1 mixture of compounds whose Rf is C ₆ H ₁₃ , C ₈ F ₁₇ , C ₁₀ F ₂₁ and C ₁₂ F ₂₅ ) and butyl methacrylate and N-methylolacrylamide 70/28/
1,1,1 containing a copolymer consisting of 2 at a concentration of 2%
-Trichloroethane solution (hereinafter referred to as solution A) 70
A solution of 30 parts of methyl ethyl ketone solution (hereinafter referred to as solution B) containing the above-mentioned TPDO at a concentration of 2% was mixed with refined cotton broadcloth (approximately 120 g/
m ² ) was immersed for about 10 seconds and squeezed with a mangle (squeezing ratio 55%). Then, after drying at 100℃ for 3 minutes, drying at 170℃ for 3 minutes.
Curing was performed for a minute. The water and oil repellency of the obtained product was measured. Regarding the durability test, water and oil repellency were measured after washing 5 times.
The results are shown in Table 1. Comparative Example 1 18.8 g (0.2 mol) of phenol, 17.4 g (0.1 mol) of 2,4-toluylene diisocyanate, and 200 g of methyl ethyl ketone were placed in a four-necked flask with an internal volume of 500 c.c. and reacted at 70°C for 4 hours. Thereafter, methyl ethyl ketone was distilled under reduced pressure and further vacuum dried to obtain 34 g of a yellowish white solid. Analysis by gas chromatography and infrared absorption spectroscopy revealed that it was the desired product. (hereinafter referred to as TDIP), the selectivity was 96%, and the yield based on 2,4-toluylene diisocyanate was 94%. Cotton broadcloth was processed in exactly the same manner as in Example 1, except that the above TDIP was used instead of TPDO, and the water and oil repellency of the product was measured. The results are shown in Table 1. Comparative example 2 2-butanone oxime 17.4g (0.2 mol), 2,4
-Toluylene diisocyanate 17.4g (0.1mol),
200g of methyl ethyl ketone was placed in a four-necked flask with an internal volume of 500c.c., and after reacting at 70℃ for 4 hours,
Methyl ethyl ketone was distilled under reduced pressure and further vacuum dried to obtain 32 g of a yellowish white solid. As a result of analysis by gas chromatography and infrared absorption spectrum, it is the target product. (hereinafter referred to as TDKO) has a selection rate of 94%, 2,
The yield based on 4-toluylene diisocyanate is
It was 91.9%. Cotton broadcloth was processed in exactly the same manner as in Example 1, except that TDKO was used instead of TPDO, and the water and oil repellency of the product was measured. The results are shown in Table 1.

[Table] As is clear from the results in Table 1, the product of Example 1 according to the present invention has significantly better water repellency than the products of Comparative Examples 1 and 2 using other blocked isocyanates. Shows oil repellency. Effects of the Invention In the present invention, a trifunctional blocked isocyanate compound having a specific structure is added as a crosslinking agent to a water and oil repellent containing a polyfluoroalkyl group and an active hydrogen group. The isocyanate group of the crosslinking agent is activated by heating, and its high reactivity increases the strength of the water and oil repellent coating and improves its adhesion to the object being treated, resulting in durable water and oil repellency. It's something you get. Furthermore, the orientation of the polyfluoroalkyl groups in the water and oil repellent is maintained well due to the specific steric structure of the crosslinking agent, and extremely excellent water and oil repellency effects can be obtained.

Claims (1)

[Scope of Claims] 1. A water and oil repellent obtained by adding and mixing a blocked isocyanate compound to a water and oil repellent containing a polyfluoroalkyl group and an active hydrogen group, wherein the blocked isocyanate compound has the general formula: (However, R ₁ and R ₂ each represent an alkyl group consisting of C _{1 to 4.} ) A water and oil repellent with improved durability, characterized by using a compound represented by the following. 2. The water and oil repellent according to claim 1, wherein the weight ratio of the water and oil repellent containing a polyfluoroalkyl group and an active hydrogen group to the blocked isocyanate compound is 45:55 to 99:1. .