JPH0372662B2 - - Google Patents

Description

[Detailed description of the invention]

Polyvinyl alcohol resins are used for applications such as adhesives, paints, coatings, and films due to their water solubility, adhesiveness, and film-forming properties, but they have the disadvantage of poor water resistance. As one method for making polyvinyl alcohol resin water resistant, a method has been proposed in which the polyvinyl alcohol resin is acetoacetylated and various crosslinking agents such as dialdehyde are added thereto to make it water resistant. However, when conventional waterproofing agents are used in combination, there are drawbacks such as an increase in the viscosity of the aqueous solution, which impairs storage stability and coating properties, and the need for a high degree of heat treatment for waterproofing. However, as a result of intensive research, the present inventors found that
A composition formed by adding (B) an isocyanate compound to (A) acetoacetylated polyvinyl alcohol resin can be easily made waterproof not only by relatively mild heat treatment but also by drying at room temperature. We have discovered the novel fact that this is possible and have completed the present invention. The water resistance effect of using isocyanate compounds is dramatically demonstrated for acetoacetylated polyvinyl alcohol resins, and far exceeds the effect of using isocyanate compounds for unmodified polyvinyl alcohol. Therefore, it must be said that the effect of the present invention is a remarkable synergistic effect due to the combination of an acetoacetyl group and an isocyanate group. In the composition of the present invention, the amount of (B) added to (A) acetoacetylated polyvinyl alcohol resin varies somewhat depending on the purpose and type of use, but usually
The composition ranges from 0.1 to 30% by weight, preferably from 0.5 to 20% by weight, particularly preferably from 1 to 10% by weight.
Although it is common to mix (B) with
There is no problem with post-processing with (B). Below, (A) and (B) will be explained in more detail. The acetoacetylated polyvinyl alcohol resin (A) in the present invention is produced by any method and is not specified. Typical examples include addition reaction of diketene to polyvinyl alcohol resin, or transesterification reaction of acetoacetate. The base polyvinyl alcohol resin may include a partially saponified polyvinyl ester such as polyvinyl acetate, or a monomer mainly composed of vinyl acetate and copolymerizable with it, such as an unsaturated carboxylic acid or a portion thereof, or Complete ester, salt, anhydride, amide, nitrile,
Unsaturated sulfonic acid or its salt, α having 2 to 30 carbon atoms
- "Copolymerized modified" polyvinyl alcohol, which is made by saponifying copolymers with olefins, vinyl ethers, etc., and "post-modified" polyvinyl alcohol, which is made by acetalizing, urethanizing, etherifying, grafting, and phosphoric acid esterification of polyvinyl alcohol. Can be used. The average degree of saponification of the polyvinyl alcohol is preferably 60 mol% or more, and the average degree of polymerization is preferably 50 to 3,000. The acetoacetylation rate for the above resin is
It is possible to increase the water solubility at 0.05 mol% or more, but it is usually selected from the range of 0.1 to 40 mol%, especially 0.2 to 20 mol%.
If the acetoacetylation rate is too low, the purpose of water resistance cannot be achieved. Furthermore, even if the acetoacetylation rate is introduced higher than necessary, the water resistance imparting effect will not be further improved, and the water solubility will often be out of the range. Further, the amount of residual vinyl acetate groups is suitably 40 mol% or less, preferably 30 mol% or less. Next, (B) isocyanate compounds used for the purpose of imparting water resistance are illustrated, but the present invention is not limited to such examples. Isocyanate compounds (e.g. tolylene diisocyanate, hydrogenated tolylene diisocyanate,
Trimethylolpropane-tolylene diisocyanate adduct, triphenylmethane triisocyanate, methylene bis(4-phenylmethane triisocyanate, isophorone diisocyanate,
and these ketoxime-blocked products or phenol-blocked products) The composition consisting of the above (A) and (B) is used for various purposes as described below. This composition exhibits unique effects in each application and is extremely useful industrially. In this case, the composition may include fillers, colorants, surfactants, fibers, foaming agents, antifoaming agents, other water-soluble resins, water-dispersible resins (such as various emulsions), and thixotropy improvers, as necessary. etc. may be added. or,
These agents are also used as post-treatment agents after treatment with compositions (A) and (B). The uses will be specifically explained below. (1) Fiber processing agents (binder for non-woven fabrics, sizing processing, hard finishing processing, binding processing, flame retardant processing, water repellent processing, pigment printing, anti-wrinkle processing, anti-shrunk processing, soft processing, imparting dimensional stability, preventing fraying) ,
This processing agent is used to improve flexibility, elasticity, dry cleaning resistance, mechanical strength, adhesion, etc. of various fibers or textiles (frotzky processing, abrasion resistance, tear resistance, stain resistance, etc.) can have a significant effect. Moreover, since it has excellent water resistance, it has good washing fastness and its effect is permanent. When using the treatment agent for textile products of the present invention, the treatment agent is applied or sprayed onto the fiber or fabric to be processed using a roll coater or the like, or the fiber or fabric is immersed in the composition. Thereafter, the amount of resin adhesion is adjusted by squeezing appropriately, and then heated and dried. When performing more advanced processing by adding cross-linking agents and waterproofing agents, the processing temperature is usually 100 to 170°C.
The process can be sufficiently progressed by heating to a certain degree. The fibers to be processed in the present invention include not only natural fibers such as cotton, silk, and western wool, but also polyamide, polyester, polyacrylic,
It also includes various synthetic fibers such as polyvinyl chloride and polypropylene. (2) Adhesives Adhesives for wood, paper, aluminum foil, plastics, etc., adhesives, rewetting agents, fibrous binders, binders for various building materials such as plasterboard and fiberboard, binders for various powder granulation, Additives for cement and mortar, pressure-sensitive adhesives, and fixing agents for anionic dyes.In such applications, it provides superior adhesive strength compared to polyvinyl alcohol. (3) Coating agents Clear coating agent for paper, pigment coating agent for paper, internal sizing agent for paper, warp glue, leather finishing agent, paint, antifogging agent, metal corrosion inhibitor,
Brightening agent, antistatic agent, conductive agent for galvanizing In such applications, a coating film with superior film strength can be obtained compared to when polyvinyl alcohol is used. (4) Molded products Fibers, films, sheets, pipes, tube leak-proof membranes, temporary coatings These molded products have extremely excellent water resistance and mechanical strength. (5) Blending agents for hydrophobic resins Antistatic agents for hydrophobic resins, hydrophilicity imparting agents, additives for composite fibers, films, and other molded products (6) Flocculants-related Flocculants for suspended and dissolved substances in water , Aqueous improver for pulp slurry (7) Soil conditioner-related (8) Photosensitive agent, electrosensitive agent-related (9) Others, ion exchange resin, ion exchange membrane related chelating resin Explain things in detail. (A) Preparation of acetoacetylated polyvinyl alcohol resin The following two resins were produced by reacting polyvinyl alcohol and diketene in an acetic acid solvent. (A)-1; average degree of polymerization 1700, residual acetic acid group 1 mol%,
Acetoacetylated polyvinyl alcohol resin with a degree of acetoacetylation of 8 mol%. (A)-2; average degree of polymerization 1100, residual acetic acid group 15 mol%,
Acetoacetylated polyvinyl alcohol resin with a degree of acetoacetylation of 15 mol%. The following compounds belonging to (B) were used and mixed with (A) to prepare a composition (composition was a 10% by weight aqueous solution) (B)-1; Tolylene diisocyanate [1% to (A) Weight % addition] (B)-2; Isophorone diisocyanate [1 weight % added to (A)] (B)-3; Trimethylolpropane-tolylene diisocyanate adduct [1 weight % to (A)]
Addition] Example 1 The water resistance of the film of the above composition was measured. The results are shown in Table 1. As a comparative example,
Water resistance was also measured when acetoacetylated polyvinyl alcohol was used alone instead of acetoacetylated polyvinyl alcohol (average degree of polymerization 1700, average degree of saponification 99 mol%). The results are also shown.

[Table] Example 2 (A)-1 and (B)-1 [However, (B)-1 is different from (A)-1
An 8% by weight aqueous solution was prepared by combining 10% by weight mixture]. A web of polyethylene terephthalate single fibers with a thickness of 3 denier and a fiber length of about 50 mm treated with a random wetper and with a dry weight of 100 g/m ² was immersed in the above liquid, squeezed with a mangle, and pre-dried at a temperature of 80°C for 20 minutes. Further, it was dried by heating at a temperature of 150°C for 5 minutes. The amount of resin deposited after drying was 30% in solids based on the weight of the web before treatment. Table 2 shows the measurement results of various properties of the obtained nonwoven fabric.

[Table] Further, a 30 x 30 cm Tetron/cotton cloth for interlining was dipped in a 5% aqueous solution having the above composition, and the liquid was squeezed out so that the amount of resin attached was 4% of the weight of the cloth. This was dried at 80°C for 10 minutes to give a hard finish. The hardness of the obtained interlining fabric was measured by a cantilever method. Further, the fabric was washed in a household electric washing machine at 40° C. for 30 minutes in a 0.3% neutral detergent bath ratio of 1/20, and then dried at room temperature, and its hardness was measured. Washability tests were also conducted after washing 5 and 10 times. The results are shown in Table 3.

[Table] Example 3 A 10% aqueous solution was prepared for a composition in which 10% by weight of (B)-1 was added to (A)-1, and a film with a thickness of 80μ was prepared by the drooling method on a glass plate. was manufactured. After immersing this film in hot water at 70° C. for 1 hour, its mechanical strength was measured using an Autograph IM-1100 model manufactured by Shimadzu (load cell 5 kg, tensile speed 100 mm/nim). The results are shown in Table 4.

[Table] Example 4 Glass-wood adhesive strength and wood-wood adhesive strength were evaluated for a composition in which 10% by weight of (B)-1 was added to (A)-1. The results are shown in Table 5.

[Table] Example 5 Paper processing was performed on a composition in which 20% by weight of (B)-1 was added to (A)-1. Size press coating was carried out under the following conditions. Coating conditions; speed 90m/nim, nip pressure 11kg/
cm, dried 115℃ 2mm Base paper; test paper (basis weight 64g/m ² , size degree 3sec, density
0.67) Cander finish: 80°C, 50Kg/cm, 2poss Coating density: 3% Table 6 shows the physical properties of the obtained coated paper.

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Claims (1)

[Scope of Claims] 1. A polyvinyl alcohol resin composition comprising (A) an acetoacetylated polyvinyl alcohol resin and (B) an isocyanate compound. 2. A fiber processing agent whose main ingredient is a polyvinyl alcohol resin composition comprising (A) an acetoacetylated polyvinyl alcohol resin and (B) an isocyanate compound. 3. An adhesive whose main ingredient is a polyvinyl alcohol resin composition comprising (A) an acetoacetylated polyvinyl alcohol resin and (B) an isocyanate compound. 4. A coating agent whose main ingredient is a polyvinyl alcohol resin composition comprising (A) an acetoacetylated polyvinyl alcohol resin and (B) an isocyanate compound.