TWI811373B - Solvent Adhesive Composition - Google Patents

Abstract

An object of the present invention is to provide a solvent-based adhesive composition that is excellent in storage stability and prevention of environmental pollution after construction. A solvent-based adhesive composition containing (A) resin, (B) organic solvent, and (C) pigment and with a specific gravity of (C) component of 3 or less has excellent storage stability and prevention of environmental pollution after construction. The content of the component (C) is preferably 0.05 to 10 parts by weight based on 100 parts by weight of the total of the components (A) and (B).

Description

Solvent-based adhesive composition

The present invention relates to a solvent-based adhesive composition that is excellent in storage stability and prevention of environmental pollution after construction.

When joining a rigid vinyl chloride pipe to a joint, the outer peripheral surface of the pipe end of the rigid vinyl chloride pipe and the inner peripheral surface of the socket of the joint are usually coated with adhesive, and the pipe end of the rigid vinyl chloride pipe is inserted into the joint. Keep it in the socket of the joint and dry it to complete the joint.

In the method of confirming that the adhesive is applied, the presence or absence of the adhesive is confirmed by visually observing the adhesive seeping out from the end surface of the joint. It is known that the adhesive itself is made to appear white in order to make it easier to recognize that the adhesive is applied. For example, Patent Document 1 describes an adhesive that exhibits white color by blending titanium white with a particle size of 1 to 10 μm in an adhesive containing a vinyl chloride resin and an organic solvent.

[Prior technical literature] [Patent Document]

[Patent document 1] Japanese Patent Application Laid-Open No. 3-86747

However, solvent-based adhesives containing titanium dioxide, that is, titanium oxide, are prone to precipitation of titanium oxide during storage, causing the adhesive composition to become uneven. If the adhesive composition becomes uneven and the dispersion amount of titanium oxide is low, if the upper layer portion is used, the shielding power will be reduced and the required visibility will not be obtained. Titanium oxide colors the adhesive composition white. However, the original white color tends to be difficult to color when applied to the widely circulated light gray standard tube, so the adhesive composition becomes white. The problem of reduced visibility caused by uneven results becomes even greater.

Therefore, by using dyes instead of pigments such as titanium oxide, visibility can be improved. Unlike titanium oxide, dyes are preferable in that they can exhibit various color tones other than white, and because they dissolve in solvents, they do not cause uneven color tones during storage. However, when working with solvent-based adhesives, the adhesives often fall to the ground. Flooring sheets and other flooring materials are usually laid on top of the fallen adhesives. However, in the case of solvent-based adhesives containing dyes, At this time, the dye in the adhesive will bleed from the back of the flooring material to the surface of the flooring material and remain on the surface. The presence of dye on the surface of this kind of adhesive will not only pollute the environment after construction, but will also become a major problem during construction. Since the dye contained in the solvent-based adhesive is adjusted to a dark color tone due to the need to pay attention to the visibility of the adhered part, there is a big problem in that the contamination caused by the dye is very obvious.

That is, there is a problem that solvent-based adhesives cannot achieve both storage stability and environmental pollution inhibitory properties.

Therefore, an object of the present invention is to provide a solvent-based adhesive composition that is excellent in storage stability and prevention of environmental pollution after construction.

The present inventors conducted diligent research and found that by including a pigment with a specific specific gravity, the storage stability of the solvent-based adhesive and the prevention of environmental pollution after construction are improved. The present invention was completed by repeated research based on this knowledge.

That is, the present invention provides inventions having aspects disclosed below.

Item 1. A solvent-based adhesive composition containing (A) resin, (B) organic solvent, and (C) pigment, and the specific gravity of the component (C) is 3 or less.

Item 2. The solvent-based adhesive composition according to Item 1, wherein the content of the component (C) is 0.05 to 10 parts by weight relative to 100 parts by weight of the total of the component (A) and the component (B).

顏料、酞菁顏料所組成之群。 Item 3. The solvent-based adhesive composition according to Item 1 or 2, wherein the component (C) is selected from azo pigments, dioxins, etc.

A group composed of pigments and phthalocyanine pigments.

紫、酞菁藍、及酞菁綠所組成之群。 Item 4. The solvent-based adhesive composition according to any one of Items 1 to 3, wherein the component (C) is selected from the group consisting of monoazo red, di-

A group consisting of purple, phthalocyanine blue, and phthalocyanine green.

Item 5. The solvent-based adhesive composition according to any one of Items 1 to 4, wherein the component (A) is a polyvinyl chloride-based resin.

Item 6. The solvent-based adhesive composition according to any one of Items 1 to 5, which is used for bonding rigid polyvinyl chloride resin pipes.

Item 7. The solvent-based adhesive composition according to any one of Items 1 to 6, which is used for adhering pipes with a brightness L ^* value of 35 or more.

According to the present invention, a solvent-based adhesive composition is provided that is excellent in both storage stability and post-construction environmental pollution prevention properties.

The solvent-based adhesive composition of the present invention is characterized by containing (A) resin, (B) organic solvent, and (C) pigment, and the specific gravity of the above-mentioned (C) component is 3 or less. Hereinafter, the solvent-based adhesive composition of the present invention will be described in detail.

[(A) Resin]

The solvent-based adhesive composition of the present invention contains resin as (A) component. As the resin, a resin soluble in component (B) can be used without particular limitation. Specifically, examples of the resin include vinyl resins. The vinyl resin is a polymer of a vinyl monomer. Specific examples thereof include vinyl chloride resin and (meth)acrylic resin, and vinyl chloride resin is preferred. These may be used individually or in combination of 2 or more types.

Examples of the vinyl chloride resin include: vinyl chloride homopolymer; copolymer of vinyl chloride monomer and a polymerizable monomer having an unsaturated bond copolymerizable with the vinyl chloride monomer; grafted vinyl chloride monomer Graft copolymers copolymerized with polymers; and chlorinated vinyl chloride resins obtained by post-chlorination of vinyl chloride resin, etc. These may be used individually or in combination of 2 or more types.

The polymerizable monomer having an unsaturated bond is not particularly limited as long as it has a radically reactive double bond and can be copolymerized with a vinyl chloride monomer using a radical polymerization initiator. Examples thereof include : α-olefins such as ethylene, propylene, butylene; vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as butyl vinyl ether and cetyl vinyl ether; (meth)acrylic acid (meth)acrylates such as ester, ethyl (meth)acrylate, butyl acrylate, and phenyl methacrylate; aromatic vinyls such as styrene and α-methylstyrene; vinylidene chloride, divinylidene chloride, etc. Halogenated ethylenes such as vinyl fluoride; and N-substituted maleimides such as N-phenylmaleimide and N-cyclohexylmaleimide. These may be used individually or in combination of 2 or more types.

The polymer for graft copolymerization of vinyl chloride is not particularly limited as long as vinyl chloride is graft polymerized. Examples thereof include: ethylene-vinyl acetate copolymer; ethylene-vinyl acetate-carbon monoxide copolymer. Material; ethylene-ethyl acrylate copolymer; ethylene-butyl acrylate-carbon monoxide copolymer; ethylene-methyl methacrylate copolymer; ethylene-propylene copolymer; acrylonitrile-butadiene copolymer; polyurethane Ester; chlorinated polyethylene; and chlorinated polypropylene, etc. These may be used individually or in combination of 2 or more types.

The average degree of polymerization of the vinyl chloride resin is not particularly limited. From the viewpoint of obtaining good bonding strength, it may be 400 or more. From the viewpoint of obtaining good solubility in component (B), it may be 400 or more. Below 1000. From the viewpoint of obtaining these effects more favorably, the average degree of polymerization of the vinyl chloride resin is preferably 600 to 1,000. In addition, the average degree of polymerization is a value measured based on JIS K6726.

Examples of the (meth)acrylic resin include homopolymers or copolymers of (meth)acrylic acid esters, and preferred examples include homopolymers or alkyl (meth)acrylic acid alkyl esters. of copolymers. These may be used individually or in combination of 2 or more types.

Examples of the (meth)acrylic acid alkyl ester include: (meth)acrylic acid methyl ester, (meth)acrylic acid ethyl ester, (meth)acrylic acid butyl ester, (meth)acrylic acid 2-ethylhexyl (meth)acrylic acid alkyl ester, Lauryl (meth)acrylate, etc. These may be used individually or in combination of 2 or more types.

As the above-mentioned (meth)acrylic acid alkyl ester, from the viewpoint of obtaining better adhesion strength, a methacrylic acid alkyl ester is preferred. Moreover, the carbon number of the alkyl group of the said alkyl (meth)acrylate is 1-20, Preferably it is 1-10, More preferably, it is 1-4.

In the above-mentioned copolymer of alkyl (meth)acrylate, other monomers copolymerized with alkyl (meth)acrylate include monomers that do not contain hydrophilic groups (hydroxyl group, carboxyl group, amino group, amide group, sulfonate group). hydrophobic monomer containing a hydrophilic group) and a hydrophilic monomer containing a hydrophilic group.

Examples of the hydrophobic monomer include nitriles such as (meth)acrylonitrile; olefins such as ethylene, propylene, isobutylene, 1-butene, styrene, and methylstyrene; vinyl formate and vinyl acetate. , vinyl esters such as vinyl propionate, vinyl pivalate, and vinyl neodecanoate; and halogenated vinyl compounds such as vinyl chloride and vinylidene chloride. These may be used individually or in combination of 2 or more types.

Examples of the hydrophilic monomer include acrylic acid, methacrylic acid, and maleic acid. Carboxylic acids such as acid, itaconic acid, fumaric acid, and crotonic acid; (meth)hydroxyethyl acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, etc. Hydroxyalkyl esters of acrylic acid; and amide such as (meth)acrylamide, N-hydroxymethylacrylamide, N,N-dimethylacrylamide, N-isopropylacrylamide, etc. . These may be used individually or in combination of 2 or more types.

In the above-mentioned (meth)acrylic resin, the content rate of the structural unit derived from the above-mentioned hydrophilic monomer is 50% or less, and preferably 30% or less from the viewpoint of obtaining better bonding strength. , preferably less than 10%. In addition, in the (meth)acrylic resin, the content rate of the structural unit derived from the (meth)acrylate is 50% or more, preferably 70%, from the viewpoint of obtaining better bonding strength. Above, preferably above 90%.

The weight average molecular weight of the (meth)acrylic resin can be 250,000 or more from the viewpoint of obtaining better bonding strength, and can be 100 from the viewpoint of obtaining good solubility in component (B). 10,000 or less, and from the viewpoint of obtaining good workability, it can be 400,000 or less. In addition, the weight average molecular weight refers to the weight average molecular weight in terms of polystyrene measured by gel permeation chromatography.

The content of component (A) in the solvent-based adhesive composition of the present invention is not particularly limited. From the viewpoint of obtaining good bonding strength, workability, etc., the lower limit may be 5% by weight or more, or more. Preferably it is 10% by weight or more, and the upper limit is 30% by weight or less, preferably 20% by weight or less. Specific ranges of the content of component (A) include 5 to 30% by weight, 5 to 20% by weight, 10 to 30% by weight, and 10 to 20% by weight.

[(B)Solvent]

The solvent-based adhesive composition of the present invention contains a solvent as component (B). As the solvent, an organic solvent capable of dissolving component (A) can be used without particular limitation. Specifically, examples of the solvent include alcohol-based organic solvents, ester-based organic solvents, ketone-based organic solvents, aliphatic hydrocarbon-based organic solvents, ether-based organic solvents, chlorine-based organic solvents, and aromatic hydrocarbon-based organic solvents. Amide-based organic solvents, glycol ether-based organic solvents, etc. These may be used individually or in combination of 2 or more types. Among these solvents, ester-based organic solvents and ketone-based organic solvents are preferred.

From the viewpoint of obtaining good workability with a short curing time (for example, 2 hours), component (B) preferably contains at least an organic solvent with a boiling point of less than 100°C. Furthermore, from the viewpoint of obtaining good bonding strength in a short curing time (for example, 2 hours), it is preferable to combine an organic solvent with a boiling point of 100°C or higher, preferably 100 to 160°C.

Examples of organic solvents having a boiling point less than 100°C include alcohol-based organic solvents such as methanol, ethanol, 2-propanol, and 1-propanol; ester-based organic solvents such as methyl acetate and ethyl acetate; acetone, methyl Ketone-based organic solvents such as ethyl ketone; aliphatic hydrocarbon-based organic solvents such as n-hexane and cyclohexane; ether-based organic solvents such as tetrahydrofuran; and chlorine-based organic solvents such as dichloromethane. These may be used individually or in combination of 2 or more types. In order to meet the Japanese Water Pipe Association standard JWWA S101, the organic solvent with a boiling point less than 100°C is preferably selected from the group consisting of acetone, tetrahydrofuran, ethyl acetate, and methyl ethyl ketone. These can be used alone or Use 2 or more types together. Among the organic solvents having a boiling point below 100°C, acetone and methyl ethyl ketone are preferred.

Examples of organic solvents having a boiling point of 100°C or higher include propyl acetate and butyl acetate. Ester-based organic solvents such as esters; aromatic hydrocarbon-based organic solvents such as toluene and xylene; ketone-based organic solvents such as methyl isobutyl ketone and cyclohexanone; amide-based organic solvents such as dimethylformamide; and Glycol ether organic solvents such as base cellosolve and ethyl cellosolve. These may be used individually or in combination of 2 or more types. In order to meet the Japanese Water Pipe Association standard JWWA S101, the organic solvent with a boiling point above 100°C is preferably cyclohexanone.

When an organic solvent with a boiling point of 100°C or higher and an organic solvent with a boiling point of less than 100°C are combined as component (B), the content of the organic solvent with a boiling point of 100°C or higher is based on 100 parts by weight of the total amount of component (B). The lower limit of the ratio is 20 parts by weight or more, preferably 30 parts by weight or more, and the upper limit is 60 parts by weight or less, preferably 50 parts by weight or less. Specific ranges of the content ratio of the organic solvent at 100° C. or higher based on 100 parts by weight of the total amount of component (B) include 20 to 60 parts by weight, 20 to 50 parts by weight, 30 to 60 parts by weight, and 30 to 50 parts by weight. parts by weight.

More specific examples of component (B) include: (B) The total amount of component 100 includes 40 to 50 parts by weight of tetrahydrofuran, 5 to 20 parts by weight of methyl ethyl ketone, and 30 to 50 parts by weight of cyclohexanone. parts by weight of a mixed solvent; (B) a mixed solvent containing 20 to 40 parts by weight of methyl ethyl ketone, 10 to 30 parts by weight of acetone, and 30 to 50 parts by weight of cyclohexanone in 100% by weight of the total component; and ( B) A mixed solvent containing 5 to 20 parts by weight of tetrahydrofuran, 40 to 60 parts by weight of methyl ethyl ketone, and 20 to 50 parts by weight of cyclohexanone in 100% by weight of the total ingredients.

The content of the component (B) in the solvent-based adhesive composition of the present invention is not particularly limited. This is because the content of the component (B) in the solvent-based adhesive composition of the present invention is set to a relatively low viscosity and good coating properties are achieved, so that the coating layer is not thick. From the viewpoint of being too thick and easily inserting the pipe into the pipe joint, it is 70% by weight or more, preferably 80% by weight or more. By ensuring the coating thickness, the solvent-based adhesive composition is applied to the pipe and From the viewpoint of efficiently compatibility with each other on the surface of the pipe joint and obtaining better adhesion, it is 95% by weight or less, preferably 90% by weight or less. Specific ranges of the content of component (B) include 70 to 95% by weight, 70 to 90% by weight, 80 to 95% by weight, and 80 to 90% by weight.

[(C)Pigment]

The solvent-based adhesive composition of the present invention contains a pigment as the (C) component. In the present invention, the term "pigment" means one that is insoluble in component (B). The term "insoluble" in component (B) means that component (C) is added to 10 times the weight of component (B) at 25°C and stirred and mixed to obtain a dispersion, and then the dispersion is controlled by solid-liquid separation. When the liquid is separated by filtration, the weight of the residue (the portion in which component (C) is soluble in component (B)) obtained by evaporating the filtrate to dryness is 1% by weight or less of the total added component (C). When working with a solvent-based adhesive composition, the adhesive composition often falls to the ground. Flooring sheets and other flooring materials are usually laid on top of the dropped adhesive. However, the solvent-based adhesive composition of the present invention By using insoluble pigments as mentioned above, component (C) in the adhesive composition will not leak out to the surface of the flooring material, so it can effectively prevent environmental pollution after construction.

In the solvent-based adhesive composition of the present invention, the specific gravity of component (C) is 3 or less. By using a pigment with a specific gravity in such a specific range, the good dispersion state of component (C) can be stably maintained even after the solvent-based adhesive composition is stored, so that the composition of the solvent-based adhesive composition is uniform. The visibility of the applied solvent-based adhesive composition can always be maintained well. From the viewpoint of obtaining this effect better, the proportion of component (C) is preferably 2.5 or more. Lower, more preferably 2.2 or less, still more preferably 2 or less. Moreover, the lower limit of the specific gravity of component (C) is not particularly limited, but for example, it may be 1 or more, preferably 1.3 or more, and more preferably 1.5 or more. Specific ranges of the specific gravity of component (C) include 1 to 3, 1 to 2.5, 1 to 2.2, 1 to 2, 1.3 to 3, 1.3 to 2.5, 1.3 to 2.2, 1.3 to 2, 1.5 to 3, and 1.5. ~2.5, 1.5~2.2, 1.5~2. In addition, the specific gravity is measured based on JISZ8807 "Measurement method of density and specific gravity of solids".

The pigment is not particularly limited, with a specific gravity of 3 or less, and examples thereof include inorganic pigments and organic pigments. Either one of the inorganic pigment and the organic pigment may be used alone, or both may be used in combination. Among these, in terms of good color development and the fact that good storage stability can be easily obtained even if it is contained at a relatively high concentration for better color development, organic Pigments.

Examples of inorganic pigments include earthen pigments (such as ocher, umber, etc.), lapis lazuli, lazuli, chalk, white bean paste, cinnabar, ultramarine blue, chrome green, cadmium red, and carbon pigments (such as carbon black, purified carbon, naphtha Rice carbon tubes, etc.), metal oxide pigments (such as iron black, cobalt blue, zinc oxide, chromium oxide, iron oxide, etc.), metal sulfide pigments (such as zinc sulfide, etc.), metal sulfates, metal carbonates (such as carbonic acid Calcium, magnesium carbonate, etc.), metal silicates, metal phosphates, metal powders (such as aluminum powder, bronze powder, zinc powder, etc.), preferably carbon pigments with small specific gravity, more preferably carbon black.

顏料(例如二

紫等)、硫靛藍顏料、蒽醌顏料、喹酞酮顏料(例如喹酞酮黃等)、金屬錯合物顏料、吡咯并吡咯二酮顏料、酞菁顏料(例如酞菁藍、酞菁綠等)，較佳為列舉偶氮顏料、二

顏料、酞菁顏料。就進而提高保存穩定性之觀點而言，作為(C)成分，較佳為列舉二

顏料、酞菁顏料(更佳為酞菁綠)。 Examples of organic pigments include: azo pigments (for example, monoazo yellow, monoazo red, monoazo violet, disazo yellow, disazo orange, pyrazolone pigments, etc.), benzimidazolone pigments , β-naphthol pigment, naphthol AS pigment, condensed azo pigment, quinacridone pigment (such as quinacridone red, quinacridone magenta, etc.), perylene pigment (such as perylene red, perylene scarlet, etc.), pyrene Ketone pigments (such as pyrenone orange, etc.), isoindolinone pigments (such as isoindolinone yellow, isoindolinone orange, etc.), isoindoline pigments (such as isoindolinone yellow, etc.), dioxins

Pigments (e.g. di

Purple, etc.), thioindigo pigments, anthraquinone pigments, quinophthalone pigments (e.g. quinophthalone yellow, etc.), metal complex pigments, diketopyrrolopyrrole pigments, phthalocyanine pigments (e.g. phthalocyanine blue, phthalocyanine green) etc.), preferably azo pigments, dioxins

Pigments, phthalocyanine pigments. From the viewpoint of further improving storage stability, as (C) component, the following two are preferred:

Pigment, phthalocyanine pigment (preferably phthalocyanine green).

These pigments can be used individually or in combination of 2 or more types. Depending on the color to be colored in the solvent-based adhesive composition of the present invention, various color tones can be expressed by using pigments alone or in combination. The color tone is not particularly limited, but from the viewpoint of visibility of the coated state, it is preferably adjusted to a dark color tone with a lightness L ^* value of 50 or less, preferably 40 or less. Furthermore, in view of the fact that the vinyl chloride resin has a yellowish tint due to age-related deterioration, in order to avoid the deterioration, it is preferable to adjust it to a blue system or a blue-violet system which is a complementary color to yellow or a hue close to it. , purple, blue-green, and green hues [lightness L ^* value: below 50 (preferably below 40), chroma a ^* value: below 60 (preferably -70~60), and chroma b ^* value: 30 or less (preferably 20 or less, more preferably -55~10)], and black [lightness L ^* value: 50 or less (preferably 40 or less, more preferably 10 or less, still more preferably is less than 5), chroma a ^* value: -20~20 (preferably -5~5, more preferably -1~1), and chroma b ^* value: -20~20 (preferably -5 ~5, preferably -1~1)] any color tone. Furthermore, in this specification, the lightness L ^* value, chromaticity a ^* value, and chromaticity b ^* value respectively refer to the lightness L ^* value measured under the D65 light source based on the CIE1976L ^* a ^* b ^* colorimetric system. , chroma a ^* value, and chroma b ^* value.

The average particle diameter of component (C) is not particularly limited. From the viewpoint of further improving storage stability, the upper limit is 500 nm or less, preferably 300 nm or less, and more preferably 260 nm or less. Since the solvent-based adhesive composition of the present invention has excellent storage stability, it is not necessary to control the average particle size of the component (C) to an extremely small average particle diameter of, for example, less than 100 nm, and can be produced at low cost. From this point of view, preferred examples of the average particle diameter of component (C) in the present invention include 150 nm or more, preferably 155 nm or more. Specific ranges of the average particle diameter of component (C) include 150 to 500 nm, 150 to 300 nm, 150 to 260 nm, 155 to 500 nm, 155 to 300 nm, and 155 to 260 nm. Furthermore, the average particle size is the volume average particle size (MV) measured by the dynamic light scattering method. Specifically, the average particle size is based on the volume-based particle size distribution measured at 25°C by using a measuring device using the dynamic light scattering method (such as Nanotrac UPA-EX150 manufactured by Nikkiso Co., Ltd.). The value is calculated from the formula (MV) = sum of (particle diameter × volume)/sum of volumes.

The content of component (C) is not particularly limited. As a lower limit, for example, from the viewpoint of ease of visibility of the coated state, the content of component (C) is, for example, based on 100 parts by weight of the total of component (A) and component (B). 0.05 parts by weight or more, preferably 0.1 parts by weight or more, more preferably 0.18 parts by weight or more, and still more preferably 0.2 parts by weight or more. The upper limit is relative to component (A) from the viewpoint of obtaining good bonding strength. and (B) component, the total of 100 parts by weight is 10 parts by weight or less, preferably 4 parts by weight or less, more preferably 2 parts by weight or less, further preferably 1 part by weight or less, and still more preferably 0.8 parts by weight It is less than or equal to 0.5 parts by weight, more preferably 0.5 parts by weight or less, and even more preferably 0.3 parts by weight or less. Specific ranges of the content of component (C) based on 100 parts by weight of the total of component (A) and component (B) include 0.1 to 10 parts by weight, 0.1 to 4 parts by weight, 0.1 to 2 parts by weight, and 0.1 to 1 part by weight, 0.1~0.8 parts by weight, 0.1~0.5 parts by weight, 0.1~0.3 parts by weight, 0.18~10 parts by weight, 0.18~4 parts by weight, 0.18~2 parts by weight, 0.18~1 part by weight, 0.18~0.8 parts by weight, 0.18~0.5 parts by weight, 0.18~0.3 parts by weight, 0.2~10 parts by weight, 0.2~ 4 parts by weight, 0.2~2 parts by weight, 0.2~1 parts by weight, 0.2~0.8 parts by weight, 0.2~0.5 parts by weight, 0.2~0.3 parts by weight.

[Other ingredients]

In addition to the above-mentioned components, the solvent-based adhesive composition of the present invention may also contain other components such as stabilizers and tackifiers as needed.

Examples of the stabilizer include lead-based stabilizers, organotin-based stabilizers, and cadmium-based stabilizers. Among them, organotin stabilizers can capture hydrogen chloride in an inert state, inhibit the formation of double bonds, and inhibit changes caused by external factors such as oxidation and light. Therefore, they are particularly suitable when using polyvinyl chloride resin as component (A). Blending. When a stabilizer is included in the solvent-based adhesive composition, its content may be, for example, 0.01 to 0.3% by weight.

Examples of the thickener include inorganic silicates, organic bentonite, inorganic bentonite, fatty acid diamides, hydrogenated castor oil, and the like. When the solvent-based adhesive composition contains a thickening agent, its content may be, for example, 1 to 15% by weight, preferably 3 to 8% by weight.

[Character]

The solvent-based adhesive composition of the present invention is adjusted to an appropriate viscosity from the viewpoint of obtaining good coating properties and making it easy to insert a pipe into a pipe joint without making the coating thickness too thick. Since the solvent-based adhesive composition of the present invention has excellent storage stability, even if it is the original The viscosity, which is detrimental to the dispersion stability of pigments, can also effectively exert storage stability. Specifically, the solvent-based adhesive composition of the present invention is preferably adjusted so that the viscosity becomes 800 mPa·s or less, preferably 500 mPa·s or less at 25°C. In addition, by ensuring the coating thickness, the solvent-based adhesive composition can be efficiently dissolved on the surface of pipes and pipe joints to obtain better adhesive strength, and/or to obtain good dispersion stability, etc. That is, it is preferably adjusted so that the viscosity becomes 100 mPa or more, preferably 125 mPa or more at 25°C. Therefore, specific viscosity of the solvent-based adhesive composition includes 100~800mPa‧s, 100~500mPa‧s, 125~800mPa‧s, and 125~500mPa‧s at 25°C.

Furthermore, when the solvent-based adhesive composition of the present invention is used for bonding pipes with a large diameter (for example, a nominal diameter of 200 mm or more), it can be more than 800 mPa, from the viewpoint of suppressing dripping. It is better to adjust the viscosity to a viscosity of 1500mPa or above, and more preferably 2000mPa‧s or above. In this case, the upper limit of the solvent-based adhesive composition of the present invention is 4000 mPa·s or less, and preferably 3000 mPa·s or less from the viewpoint of ease of coating (coating spread). Therefore, as another specific example of the viscosity of the solvent-based adhesive composition, the viscosity exceeds 800mPa and is 4000mPa‧s or less, exceeds 800mPa and is 3000mPa‧s or less, 1500~4000mPa‧s, 1500~3000mPa‧s, 2000~4000mPa‧s, 2000~3000mPa‧s.

Furthermore, in this specification, the viscosity is measured at 25°C using a B-type viscometer with spindle No. 2 and a rotation speed of 30 rpm.

[Manufacturing method]

The solvent-based adhesive composition of the present invention can be prepared by appropriately mixing the component (A), component (B) and component (C) mentioned above. For example, a method may be as follows: After preparing a composition having a relatively large resin content by mixing component (A) and component (C) with a part of component (B) using a dispersion mixer, etc., the remaining component (B) is added. Mix.

[use]

The solvent-based adhesive composition of the present invention can be used for connecting pipes. More specifically, it can be used to join pipes and pipe joints. This joint can be achieved by coating the outer peripheral surface of the pipe end of the pipe and the inner peripheral surface of the socket of the pipe joint with a solvent-based adhesive composition to connect the pipe end of the pipe. Insert it into the socket of the pipe joint and keep it dry.

Since the solvent-based adhesive composition of the present invention will not seep out from the back of the flooring material to the surface of the flooring material, the solvent-based adhesive composition can effectively prevent environmental pollution after construction. Therefore, it is suitable for pipes using the solvent-based adhesive composition of the present invention. Even if the solvent-based adhesive composition falls to the ground during the connection work, flooring materials such as floor sheets can be laid thereon without removing the dropped solvent-based adhesive composition. From this point of view, preferred examples of flooring materials such as floor sheets include polyvinyl chloride-based resin flooring materials that are inherently prone to bleeding of solvent-based adhesive compositions containing dyes.

In order to confirm the coating state by visually recognizing the color tone of the solvent-based adhesive composition at the joint, it is preferable that at least one of the pipe and the pipe joint, and it is preferable that the pipe joint be made of a transparent resin. On the other hand, the application object (preferably a tube) made of opaque resin preferably exhibits a non-dark tone with a lightness L ^* value of 35 or more, and more preferably exhibits a gray tone. Specific hues of gray-based tubes include lightness L ^* value: 35 or more, chroma a ^* value: -5~1, and chroma b ^* value: -5~1, preferably lightness L ^* value. : 40 or more, preferably 40~80, chroma a ^* value: -5~1, and chroma b ^* value: -5~1 light gray tone. Since the solvent-based adhesive composition of the present invention can be adjusted to a dark color tone by the component (C), the visibility is particularly excellent when applied to such a non-dark color pipe with a relatively bright color. In addition, such non-dark color tubes with relatively bright colors are standardized and widely distributed, so the solvent-based adhesive composition of the present invention is very useful.

In terms of easily accepting compatibility with component (B) and obtaining good bonding strength, it is preferred that at least one of the pipes and pipe joints to be used for the solvent-based adhesive composition of the present invention is at least one of the pipes and pipe joints. First, it is preferable that at least the pipe, and more preferably both the pipe and the pipe joint, are made of rigid polyvinyl chloride resin.

The pipe to which the solvent-based adhesive composition of the present invention is applied is preferably a polyvinyl chloride resin pipe, and is not particularly limited. Examples include water pipes, hot water pipes, high-temperature drainage pipes, sewer pipes, and agricultural pipes. Water pipes, drainage pipes/ventilation pipes/communication cable protection pipes, building drainage vent pipes, air conditioning drainage pipes, etc.

[Example]

The present invention will be described in more detail below using examples, but the present invention is not limited to these.

Test example

A solvent-based adhesive composition having the composition shown in Table 1 and Table 2 was prepared. Furthermore, in Table 1, as the vinyl chloride resin, a polyvinyl chloride homopolymer with an average degree of polymerization of 800 was used, and as the solvent, a mixture of organic solvents with a boiling point of 50 to 150°C, specifically cyclohexanone, was used: Methyl ethyl ketone: acetone = 45: 30: 20 (weight ratio). As the carbon black, product number PMKPMMB # 49 manufactured by Sakura Cray-Pas Co., Ltd. was used. The prepared solvent-based adhesive composition was subjected to the following measurement and evaluation tests.

(Measurement of specific gravity of pigments)

The specific gravity of the pigment is measured based on JISZ8807 "Method for determination of density and specific gravity of solids".

(Measurement of average particle size of pigments)

The pigment was added to methyl ethyl ketone and dispersed for 10 minutes using an ultrasonic cleaning device (W-113MkII manufactured by Honda Electronics Co., Ltd.) to obtain a dispersion liquid. For the dispersion, based on the volume-based particle size distribution obtained by the dynamic light scattering method using Nanotrac UPA-EX150 manufactured by Nikkiso Co., Ltd. at 25°C, based on the volume average particle size (MV) = (particle size × volume) The volume average particle size (MV) is calculated using the formula of sum/sum of volume.

(Measurement of viscosity)

Using a B-type viscometer (model BMII manufactured by Toki Sangyo Co., Ltd.), the measurement was performed at 25° C. with rotor No. 2 and a rotation speed of 30 rpm, 30 seconds after the start of autorotation.

(Evaluation of storage stability)

Place 100 g of the solvent-based adhesive composition into a glass spiral tube (Model No. 5-128-03), cover it, and store it in a 40°C environment for 2 months. The degree of storage stability is evaluated based on the following criteria.

◎: No precipitation at all (no change)

○: Only slight precipitation is observed at the bottom, but the color of the solution is uniform from the bottom to the liquid surface.

△: A little precipitate is confirmed at the bottom. Although the color tone of the solution is uneven (gradient, light and dark), the solution is colored from the bottom to the liquid surface.

×: Complete precipitation is confirmed and a transparent layer is formed on top of the solution.

(Evaluation of vinyl chloride sheet bleeding properties (pollution prevention properties))

1 g of the solvent-based adhesive composition was applied to the back side of a soft polyvinyl chloride sheet (manufactured by Toli Co., Ltd., model TS2118, thickness 2.0 mm) and dried to obtain a test piece. Let the test pieces stand for 48 hours under normal pressure and 60°C. The vinyl chloride sheet's bleeding properties (contamination prevention properties) were evaluated based on the following criteria.

○: The color of the solvent-based adhesive composition is not visible on the surface of the polyvinyl chloride sheet. If the cross-section of the polyvinyl chloride sheet is observed, the color of the solvent-based adhesive composition does not enter the polyvinyl chloride. Inside the sheet.

△: Although the color of the solvent-based adhesive composition was not visible on the surface of the polyvinyl chloride sheet, if the cross-section of the polyvinyl chloride sheet was observed, it was confirmed that the color of the solvent-based adhesive composition penetrated into the polyvinyl chloride sheet. Inside the vinyl chloride sheet.

×: The color of the solvent-based adhesive composition is visible on the surface of the polyvinyl chloride sheet. If the cross-section of the polyvinyl chloride sheet is observed, the solvent-based adhesive composition is visible inside the polyvinyl chloride sheet. Color reaches the surface.

(evaluation of visual recognition)

A solvent-based adhesive composition is used to connect a rigid polyvinyl chloride resin pipe (U-PVC pipe) for tap water pipes to a rigid polyvinyl chloride pipe joint for tap water pipes. The visibility of the solvent-based adhesive composition of the joint part (adhesive coated part) was evaluated based on the following criteria. Furthermore, the L ^* a ^* b ^* values of the U-PVC pipe used are lightness L ^* value: 43, chroma a ^* value: -2, and chroma b ^* value: -2.

○: The presence of adhesive can be easily visually confirmed

×: The presence or absence of adhesive cannot be visually confirmed

The L ^* a ^* b ^* values of U-PVC pipes and solvent-based adhesive compositions were measured using a side colorimeter (model: ZE-2000) manufactured by Nippon Denshoku Industries Co., Ltd.

(Evaluation of adhesion evaluation)

Based on the JWWA S101-2006 standard for rigid polyvinyl chloride pipe adhesives for tap water pipes, the adhesive strength (MPa) after 15 minutes and 2 hours was measured. Regarding the obtained adhesive strength, the adhesive strength was evaluated based on the following criteria. In addition, based on this standard, the adhesive force after 15 minutes is 1.25MPa or more and the adhesive force after 2 hours is 2.5MPa or more is qualified.

‧After 15 minutes

A: 1.45MPa or more

B: 1.25MPa or more and less than 1.45MPa

C: Less than 1.25MPa

‧After 2 hours

A: 3.4MPa or more

B: 3.1MPa or more but less than 3.4MPa

C: 2.8MPa or more but less than 3.1MPa

D: 2.5MPa or more but less than 2.8MPa

E: Less than 2.5MPa

The results are shown in Table 1 and Table 2. From Table 1 and Table 2, it is clear that when a resin, a solvent, and a pigment with a specific gravity exceeding 3 are included (Comparative Examples 1 and 2), the storage stability is poor and the pigment is completely precipitated. Furthermore, when a pigment with a specific gravity exceeding 3 is included to satisfy the adhesion strength (Comparative Example 1), the visibility of the coated state is also poor. When a pigment with a specific gravity exceeding 3 is included to satisfy the visibility (Comparative Example 1) In Comparative Example 2), the adhesiveness also deteriorated. Furthermore, in the case where a resin, a solvent, and a dye are included (Comparative Examples 3 to 5), the storage stability is good, but the evaluation of vinyl chloride sheet bleeding properties (contamination prevention properties) is poor. On the other hand, when a resin, a solvent, and a pigment with a specific gravity of 3 or less are included (Examples 1 to 9), the storage stability is good, the colored state is maintained, and the vinyl chloride sheet bleeding property (contamination prevention property) is evaluated Also good. In addition, the visibility of the coated state is also good.

Claims (5)

A solvent-based adhesive composition, which includes (A) resin, (B) organic solvent, and (C) pigment. The above component (A) is a polyvinyl chloride resin, and the above component (C) is selected from azo pigments. ,two

A group consisting of pigments and phthalocyanine pigments, and the specific gravity of the above component (C) is 3 or less. The solvent-based adhesive composition of claim 1, wherein the content of the component (C) is 0.05 to 10 parts by weight relative to 100 parts by weight of the total of the components (A) and (B). The solvent-based adhesive composition of claim 1 or 2, wherein the above component (C) is selected from the group consisting of monoazo red, di-

A group consisting of purple, phthalocyanine blue, and phthalocyanine green. The solvent-based adhesive composition of claim 1 or 2 is used for bonding rigid polyvinyl chloride resin pipes. Such as the solvent-based adhesive composition of claim 1 or 2, which is used to bond pipes with a brightness L ^* value of 35 or more.