Curing agent microcapsule aqueous copolymer emulsion
By preparing isocyanate microcapsules coated with polyurea/polyurethane shells in aqueous copolymer emulsions, the compatibility problem between isocyanate compounds and aqueous copolymer emulsions was solved, achieving high adhesion and water resistance, extending the pot life and simplifying the preparation process.
Patent Information
- Application Number
- CN202511481860.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-16
- Publication Date
- 2026-02-27
AI Technical Summary
In the prior art, the compatibility between isocyanate compounds and aqueous copolymer emulsions is poor, resulting in insufficient adhesion and water resistance. Furthermore, isocyanate compounds are prone to side reactions with reactive hydrogen-containing compounds, leading to a short pot life.
Isocyanate microcapsules coated with polyurea/polyurethane shells are prepared in an aqueous copolymer emulsion to form a core-shell structure of curing agent microcapsules in the aqueous copolymer emulsion. The microcapsules are stored stably at room temperature using physical isolation effects and release active isocyanate compounds for bonding under high temperature or pressure.
It improves the compatibility and adhesion water resistance of isocyanate compounds with aqueous copolymer emulsions, extends the pot life, simplifies the preparation process, and increases the solid content.
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Figure CN121574340A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the preparation of a curing agent microcapsule water-based copolymer emulsion, in particular to a preparation method of a polyurea / polyurethane shell material isocyanate microcapsule water-based copolymer emulsion and its application, etc. BACKGROUND
[0002] Isocyanate compounds are a classic curing agent, which are various, are basic monomers for synthesizing the world's six major polymer materials polyurethane, and are widely concerned in the fields of adhesives, coatings, foam plastics, self-repair, etc. The highly unsaturated isocyanate functional group has extremely high chemical activity with active hydrogen-containing compounds (water, alcohol, acid, etc.), and can form dimers under certain conditions through self-polymerization, so that the pot life is short. The common solution is chemical blocking method, that is, using some compounds that can react with isocyanate compounds to block the isocyanate functional group. The blocked isocyanate compound is first added to the reaction system, and then is unblocked under certain conditions. However, the unblocking temperature is generally high, the blocking agent is toxic, and the process conditions are complex. Another method is physical isolation method, that is, microcapsule coating method, which specifically uses emulsion polymerization to coat isocyanate compounds with high molecular shell materials, so that they can stably coexist with other active hydrogen-containing compounds. Subsequently, under pressure or high temperature conditions, the broken shell material can form hydrogen bonds, intermolecular forces, etc. with the active isocyanate compound released and the water-based copolymer emulsion or the bonded object, realizing firm bonding and water resistance.
[0003] Two-component adhesives are mainly composed of water-based copolymer emulsion, which has good adhesion, water resistance and heat resistance. The general process is to directly mix isocyanate compounds with water-based copolymer emulsion in proportion, but the compatibility of the two is poor, and the isocyanate compound is easy to react with active hydrogen-containing compounds, so the pot life is short. Therefore, it needs to be prepared and used immediately in actual operation. In order to improve the compatibility and pot life, isocyanate microcapsule emulsion can be prepared first, and then isocyanate microcapsule emulsion and water-based copolymer emulsion can be mixed uniformly in a certain proportion, but the solid content is lower than that of directly adding isocyanate compounds, resulting in a decrease in adhesion and water resistance. SUMMARY
[0004] In order to solve the above technical problems, the present application provides a preparation method of a curing agent microcapsule water-based copolymer, which is specifically embodied in the following technical solutions: The curing agent microcapsule water-based copolymer emulsion is a curing agent microcapsule water-based copolymer emulsion coated with a polyurea / polyurethane shell material prepared by adding an isocyanate curing agent into a water-based copolymer emulsion under certain conditions. Due to the physical isolation effect of the shell material, the curing agent microcapsule water-based copolymer emulsion can be stored stably at room temperature for half a year. When pressurized or under high-temperature conditions, the active isocyanate compound released after the shell material is broken can react with the active hydrogen compound to achieve intelligent controllable bonding and water resistance.
[0005] The application provides a curing agent microcapsule water-based copolymer emulsion, wherein the curing agent microcapsule has a core-shell structure, the core material is an isocyanate liquid, and the wall material is polyurea / polyurethane. The curing agent microcapsule water-based copolymer emulsion contains spherical isocyanate microcapsules with a particle size of 10-60 μm and irregular particles with a size of 2-5 μm inherent in the water-based copolymer emulsion.
[0006] The wall material is a polyurea / polyurethane shell material prepared by an emulsion polymerization method, and is prepared by water and a small amount of an external molecular chain extender and the self-loss part of the core material isocyanate in the water-based copolymer emulsion.
[0007] The water-based copolymer emulsion is one or more of an acrylate copolymer emulsion, a vinyl acetate-ethylene copolymer emulsion, a starch-based emulsion, a soybean protein-based emulsion or a water-based polyurethane emulsion.
[0008] The curing agent is an aromatic isocyanate or an aliphatic isocyanate compound. The aliphatic isocyanate includes one or more of 1,6-cyclohexyl diisocyanate, isophorone diisocyanate and 1,4-cyclohexane diisocyanate.
[0009] The aromatic isocyanate includes one or more of 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, p-phenylene diisocyanate and polymethylene polyphenyl polyisocyanate. The emulsion polymerization method also selectively contains an emulsifier, and the emulsifier is selected from one or more of sodium dodecyl benzene sulfonate, an alkyl quaternary ammonium salt, Tween, Span, sodium hydroxymethyl cellulose and gum arabic.
[0010] The molecular chain extender is a compound containing a hydroxyl group or an amino group, and includes one or more of 1,4-butanediol, methylpropanediol, polyethylene glycol, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, isophorone diamine and polyether amine.
[0011] Based on this, the application also provides a preparation method of the curing agent microcapsule water-based copolymer emulsion, which mainly includes the following steps: S1: a certain solid content of water-based copolymer emulsion, without or with a small amount of emulsifier, is uniformly dispersed, namely the water phase; S2: under certain temperature and stirring rate conditions, a certain mass of isocyanate curing agent is added into the water-based copolymer emulsion phase for emulsification, to obtain an oil-in-water emulsion. S3: the stirring mode is changed or continued, under certain stirring rate conditions, the temperature is slowly raised to a certain temperature, and a certain mass of molecular chain extender is slowly added, and the temperature is kept for a period of time. After cooling to room temperature, the curing agent microcapsule water-based copolymer emulsion is obtained.
[0012] In some embodiments, the solid content of the water-based copolymer emulsion in step S1 is 40-70%, the amount of the emulsifier added is 0-10% of the mass of the water-based copolymer emulsion, and the solid content of the emulsifier aqueous solution is 2-10%.
[0013] In some embodiments, the mass ratio of the isocyanate to the water-based copolymer emulsion in step S2 is (0.3-0.5):1.
[0014] In some embodiments, the emulsification temperature in step S2 is 20-30℃, the emulsification rate is 800-1200rpm, the emulsification time is 5-60min, further preferably the emulsification time is 5-30min, further preferably the emulsification time is 5-20min, and further preferably the emulsification time is 5-10min.
[0015] When the water-based copolymer emulsion is used as the water phase, changing the stirring mode and the emulsification time will have a greater impact on the particle size than when water is used as the water phase. Generally, the greater the shear force generated by the stirring rate or the longer the emulsification time, the smaller the particle size of the curing agent microcapsule, which is not conducive to release under external stimulation.
[0016] In some embodiments, the stirring mode in step S3 is one or more of a dispersion disc, a one-letter pulp, a sheet paddle, a propeller, a frame or an anchor paddle, and the stirring conditions are 40-50℃, 500-800rpm, and 1-5h. The replacement of the stirring mode can be simply achieved by temporarily raising and lowering the stirring shaft, and loosening the replacement of another fixed mode.
[0017] In some embodiments, the mass ratio of the molecular chain extender to the isocyanate in step S3 is (0.1-0.2):1.
[0018] The change of the stirring mode is based on the fact that the shear force required in the emulsification and coating stages is different, to prevent the formed microcapsule emulsion from being stirred to pieces, so that the isocyanate compound reacts with the water-based copolymer emulsion in advance. Without adding a molecular chain extender, the compactness of the shell material is poor, which also shortens the room temperature storage period.
[0019] The technical innovation point of the present application is that the present application provides a curing agent microcapsule water-based copolymer emulsion and a preparation method thereof. Compared with directly adding isocyanate curing agent or curing agent microcapsule emulsion in the water-based copolymer emulsion, the present application has obvious advantages: (1) under the condition of no emulsifier and catalyst, isocyanate microcapsule emulsion is prepared by using water in the water-based copolymer, additional molecular chain extender and a small amount of self-loss isocyanate core material; (2) the solid content of the curing agent water-based copolymer emulsion is higher than that of directly mixing isocyanate microcapsule emulsion and water-based copolymer emulsion, and the water resistance of the adhesive is good; (3) the preparation environment is water-based copolymer emulsion, which reduces the mixing process and is easy to be industrialized. The water-based copolymer emulsion for preparing microcapsules can be compounded with active isocyanate curing agent to improve the bonding and water resistance. The preparation of the curing agent microcapsule emulsion and the mixing of the curing agent microcapsule emulsion and the water-based copolymer emulsion are realized at one step. The curing agent microcapsule water-based copolymer emulsion is widely used in the fields of coatings, wood, leather fabrics, adhesives and electronic industry. BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure 1 The curing agent microcapsule acrylate copolymer emulsion (A) prepared in Example 1 and the microscope graph of the curing agent microcapsule vinyl acetate-ethylene copolymer emulsion prepared in Example 3 (B).
[0021] Figure 2 The particle size graph of the curing agent microcapsule acrylate copolymer and the acrylate copolymer emulsion prepared in Example 1 (A) and the particle size graph of the curing agent microcapsule vinyl acetate-ethylene copolymer and the vinyl acetate-ethylene copolymer emulsion prepared in Example 3 (B). DETAILED DESCRIPTION
[0022] The curing agent microcapsule water-based copolymer emulsion and the preparation method thereof will be further described in combination with specific embodiments, but the embodiments of the present application are not limited thereto. 1 part in the examples of the present application refers to 1 g.
[0023] Example 1 Under the condition of 800 rpm stirring, 30 parts of hexamethylene diisocyanate liquid was added into the water-based copolymer emulsion phase, and emulsified for 10 min at room temperature and 800 rpm to obtain an oil-in-water emulsion. The stirring mode was changed to a dispersion disc, and the temperature was slowly increased to 45℃ at 500 rpm, and a certain amount of molecular chain extender 1,4-butanediol was slowly added, and the temperature was kept for 3 h. After cooling to room temperature, hexamethylene diisocyanate microcapsule acrylate copolymer emulsion was obtained.
[0024] The obtained hexamethylene diisocyanate microcapsule acrylate copolymer emulsion is shown in FIG. A and FIG. B. Figure 1 A. FIG. B shows the microscope graph of the curing agent microcapsule vinyl acetate-ethylene copolymer emulsion prepared in Example 3. Figure 2A shows the particle size distribution of hexamethylene diisocyanate microcapsule acrylate copolymer emulsion and acrylate copolymer emulsion. The obvious spherical particles are curing agent microcapsules with a particle size D90 of 50 μm, while the others are irregular particles of 2-3 μm inherent in the aqueous copolymer emulsion.
[0025] Example 2 100 parts of an acrylate copolymer emulsion (40% solids content) were mixed with 10 parts of 10% sodium dodecylbenzenesulfonate to form an aqueous phase. Under stirring at 800 rpm, 30 parts of hexamethylene diisocyanate liquid were added to the aqueous copolymer emulsion phase. The mixture was emulsified at 800 rpm for 10 minutes at room temperature to obtain an oil-in-water emulsion. The mixture was then stirred using a dispersion disc and slowly heated to 45°C at 500 rpm, with a certain mass of the chain extender methyl propylene glycol slowly added. The mixture was kept at this temperature for 3 hours. After cooling to room temperature, the hexamethylene diisocyanate microcapsule acrylate copolymer emulsion was obtained.
[0026] Example 3 Using 100 parts of vinyl acetate-ethylene copolymer emulsion (55% solids content) as the aqueous phase, 30 parts of 1,6-cyclohexyl diisocyanate liquid were added to the aqueous copolymer emulsion phase under stirring at 800 rpm. Emulsification was carried out at room temperature and 800 rpm for 10 min to obtain an oil-in-water emulsion. The mixture was then stirred using a dispersion disc, and the temperature was slowly increased to 45°C at 500 rpm, with a certain mass of polyetheramine, a molecular chain extender, being slowly added. The mixture was kept at this temperature for 3 h. After cooling to room temperature, hexamethylene diisocyanate microcapsules of vinyl acetate-ethylene copolymer emulsion were obtained.
[0027] The obtained hexamethylene diisocyanate microcapsule vinyl acetate-ethylene copolymer emulsion is shown in the attached figure. Figure 1 As shown in B. (Attachment) Figure 2 B shows the particle size distribution of hexamethylene diisocyanate microcapsules in vinyl acetate-ethylene copolymer emulsion and vinyl acetate-ethylene copolymer emulsion. The obvious spherical particles are curing agent microcapsules with a particle size D90 of 25 μm, while the others are irregular particles of 3-5 μm inherent in the aqueous copolymer emulsion.
[0028] Example 4 100 parts of vinyl acetate-ethylene copolymer emulsion (solid content 55%) was mixed with 10 parts of 10% sodium dodecyl benzene sulfonate emulsion to form the water phase. 30 parts of 1,4-cyclohexane diisocyanate was added to the water-based copolymer emulsion phase under stirring at 800 rpm, and emulsified at room temperature for 10 minutes at 800 rpm to obtain an oil-in-water emulsion. The stirring mode was changed to a dispersing disc, and the temperature was slowly raised to 45°C at 500 rpm, and a certain amount of molecular chain extender diethylene triamine was slowly added, and the temperature was kept for 3 hours. After cooling to room temperature, a hexamethylene diisocyanate microcapsule vinyl acetate-ethylene copolymer emulsion was obtained.
[0029] Comparative Example 1 100 parts of 10% sodium dodecyl benzene sulfonate emulsion was used as the water phase, and 30 parts of hexamethylene diisocyanate liquid was added to the water-based copolymer emulsion phase under stirring at 800 rpm, and emulsified at room temperature for 10 minutes at 800 rpm to obtain an oil-in-water emulsion. The stirring mode was changed to a dispersing disc, and the temperature was slowly raised to 45°C at 500 rpm, and a certain amount of molecular chain extender 1,4-butanediol was slowly added, and the temperature was kept for 3 hours. After cooling to room temperature, a hexamethylene diisocyanate microcapsule emulsion was obtained. The hexamethylene diisocyanate microcapsule emulsion and the acrylate copolymer emulsion were mixed uniformly in a certain proportion with a high-speed stirrer to obtain a hexamethylene diisocyanate microcapsule acrylate copolymer emulsion.
[0030] Comparative Example 2 100 parts of 10% sodium dodecyl benzene sulfonate emulsion was used as the water phase, and 30 parts of hexamethylene diisocyanate liquid was added to the water-based copolymer emulsion phase under stirring at 800 rpm, and emulsified at room temperature for 10 minutes at 800 rpm to obtain an oil-in-water emulsion. The stirring mode was changed to a dispersing disc, and the temperature was slowly raised to 45°C at 500 rpm, and a certain amount of molecular chain extender 1,4-butanediol was slowly added, and the temperature was kept for 3 hours. After cooling to room temperature, a hexamethylene diisocyanate microcapsule emulsion was obtained. The hexamethylene diisocyanate microcapsule emulsion and the acrylate copolymer emulsion were mixed uniformly in a certain proportion with a high-speed stirrer to obtain a hexamethylene diisocyanate microcapsule acrylate copolymer emulsion.
[0031] Comparative Example 3 100 parts of 10% sodium dodecyl benzene sulfonate emulsion was used as the water phase, and 30 parts of hexamethylene diisocyanate liquid was added to the water-based copolymer emulsion phase under stirring at 800 rpm, and emulsified at room temperature for 10 minutes at 800 rpm to obtain an oil-in-water emulsion. The stirring mode was changed to a dispersing disc, and the temperature was slowly raised to 45°C at 500 rpm, and a certain amount of molecular chain extender 1,4-butanediol was slowly added, and the temperature was kept for 3 hours. After cooling to room temperature, a hexamethylene diisocyanate microcapsule emulsion was obtained. The hexamethylene diisocyanate microcapsule emulsion and the acrylate copolymer emulsion were mixed uniformly in a certain proportion with a high-speed stirrer to obtain a hexamethylene diisocyanate microcapsule acrylate copolymer emulsion.
[0032] Comparative Example 4 With 100 parts of the acrylate copolymer emulsion (solid content 40%) as the water phase, 30 parts of hexamethylene diisocyanate liquid was added into the water-based copolymer emulsion phase under stirring at 800 rpm, and emulsified at 800 rpm for 120 min at room temperature to obtain an oil-in-water emulsion. The stirring mode was changed to a dispersion disc, and the temperature was slowly raised to 45°C at 500 rpm, and a certain amount of molecular chain extender 1,4-butanediol was slowly added, and incubated for 3 h. After cooling to room temperature, the hexamethylene diisocyanate microcapsule acrylate copolymer emulsion was obtained.
[0033] Comparative Example 5 With 100 parts of the acrylate copolymer emulsion (solid content 40%) as the water phase, 30 parts of hexamethylene diisocyanate liquid was added into the water-based copolymer emulsion phase under stirring at 800 rpm, and emulsified at 800 rpm for 120 min at room temperature to obtain an oil-in-water emulsion. The stirring mode was changed to a dispersion disc, and the temperature was slowly raised to 45°C at 500 rpm, and a certain amount of molecular chain extender 1,4-butanediol was slowly added, and incubated for 3 h. After cooling to room temperature, the hexamethylene diisocyanate microcapsule acrylate copolymer emulsion was obtained.
[0034] Performance test: The curing agent microcapsule water-based copolymer emulsion of the above examples was stored in a cool, dark, sealed room at room temperature, and the room temperature latency was observed. The adhesive effect of the composition under the condition of 2-5 MPa was tested by a universal tensile testing machine, and after being placed at room temperature for a period of time, the adhesive property and water resistance were tested by soaking in cold water or boiling water.
[0035] Table 1 Results of the curing agent microcapsule water-based copolymer emulsion prepared in the examples and comparative examples
[0036] From the comparison results of Examples 1 and 2, 3 and 4, it can be seen that whether no or a small amount of 10% emulsifier is added, hexamethylene diisocyanate microcapsule acrylate copolymer emulsion and hexamethylene diisocyanate microcapsule vinyl acetate-ethylene copolymer emulsion can be prepared in acrylate copolymer or vinyl acetate-ethylene copolymer emulsion, respectively. However, the addition of emulsifier leads to a low solid content of 3-4% and slightly poor water resistance.
[0037] From the comparison results of Examples 1 and 3, it can be seen that the room temperature latency of the curing agent microcapsule water-based copolymer emulsion is not different, the solid content of the vinyl acetate-ethylene copolymer is 15% higher than that of the acrylate emulsion, and the particle size D90 of the hexamethylene diisocyanate microcapsule obtained is 25 μm smaller, which may lead to a small number of broken microcapsules in the pressure test, and slightly poor adhesive water resistance.
[0038] From the comparison results of the comparative example 1 and the example 1, it can be seen that the solid content of the prepared curing agent microcapsule emulsion is 15.6% lower than that of the curing agent microcapsule acrylate copolymer emulsion prepared directly, and thus the storage period at room temperature is shortened and the water resistance of the adhesive is poor.
[0039] From the comparison results of the comparative example 2 and the example 1, it can be seen that the latent period at room temperature is shortened and the water resistance is poor without the molecular chain extender system. The reason is that the compactness of the microcapsule shell material is poor and the active isocyanate compound is easy to seep out.
[0040] From the comparison results of the comparative example 3 and the example 1, it can be seen that the latent period at room temperature is shortened and the water resistance is poor with the same stirring method for emulsification and coating. The reason is that the shear force required to overcome the viscosity of the water-based copolymer emulsion in the emulsification stage is not suitable for the coating stage, and the larger shear force will cause cracks and damage to the high molecular shell material, so that the active isocyanate compound is easy to seep out.
[0041] From the comparison results of the comparative examples 4 and 5 and the example 1, it can be seen that increasing the stirring speed and prolonging the stirring time will reduce the particle size of the isocyanate microcapsule, so that it is not easy to break the shell under the same stress test conditions, resulting in poor water resistance of the adhesive.
[0042] The above is only a specific embodiment of the present application, and it should be noted that for the research and development technicians in the field, some improvements and refinements can be made without departing from the principles of the present application, and these should also be considered as the protection scope of the present application.
Claims
1. A curing agent microcapsule aqueous copolymer emulsion, characterized in that: The curing agent microcapsules have a core-shell structure, with the core material being an isocyanate-based curing agent and the wall material being polyurea / polyurethane. The curing agent microcapsule aqueous copolymer emulsion contains spherical curing agent microcapsules with a particle size of 10-60 μm and irregular particles of 2-5 μm inherent in the aqueous copolymer emulsion.
2. The curing agent microcapsule aqueous copolymer emulsion according to claim 1, characterized in that: The wall material is a polyurea / polyurethane prepared by emulsion polymerization, specifically by water in an aqueous copolymer emulsion and a small amount of added molecular chain extender and isocyanate for the self-loss core material.
3. The curing agent microcapsule aqueous copolymer emulsion according to claim 1, characterized in that: The aqueous copolymer emulsion is one or more of the following: acrylate copolymer emulsion, vinyl acetate-ethylene copolymer emulsion, styrene-acrylic emulsion, starch-based emulsion, and soybean protein-based emulsion.
4. The curing agent microcapsule aqueous copolymer emulsion according to claim 1 or 2, characterized in that: The curing agent is an aromatic isocyanate or an aliphatic isocyanate compound; Aromatic isocyanates include one or more of 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, terephthalic diisocyanate, and polymethylene polyphenyl polyisocyanate; Aliphatic isocyanate compounds include one or more of 1,6-cyclohexyl diisocyanate, isoflurone diisocyanate, and 1,4-cyclohexane diisocyanate.
5. The curing agent microcapsule aqueous copolymer emulsion according to claim 2, characterized in that: The emulsion polymerization method may also selectively contain an emulsifier, which is selected from one or more of sodium dodecylbenzenesulfonate, alkyl quaternary ammonium salt, Tween, Span, sodium hydroxymethyl cellulose, and gum arabic.
6. The curing agent microcapsule aqueous copolymer emulsion according to claim 1, characterized in that: The chain extender is a compound containing hydroxyl or amino groups, including one or more of 1,4-butanediol, methylpropanediol, polyethylene glycol, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, isophorone diamine, and polyetheramine.
7. A method for preparing an aqueous copolymer emulsion of curing agent microcapsules as described in any one of claims 1-6, characterized in that: S1: Aqueous copolymer emulsions with a certain solid content, dispersed evenly with little or no added emulsifier, constitute the aqueous phase; S2: Under certain temperature and stirring rate conditions, a certain mass of isocyanate curing agent is added to the aqueous phase for emulsification to obtain an oil-in-water emulsion. S3: Change the stirring method, slowly heat to a certain temperature under a certain stirring rate, slowly add a certain mass of molecular chain extender, keep the temperature in a gradient for a period of time, and cool to room temperature to obtain the curing agent microcapsule aqueous copolymer emulsion.
8. The curing agent microcapsule aqueous copolymer emulsion according to claim 7, characterized in that: The solid content of the aqueous copolymer emulsion in step S1 is 40-70%; The mass ratio of the curing agent and the aqueous copolymer emulsion in step S2 is (0.3-0.5):1; The mass ratio of the molecular chain extender to the curing agent in step S3 is (0.1-0.2):
1.
9. The curing agent microcapsule aqueous copolymer emulsion according to claim 7, characterized in that: The emulsification temperature in step S2 is 20-30°C, the emulsification rate is 800-1200 rpm, and the emulsification time is 5-60 min. The stirring method described in step S3 is one or more of the following: dispersion disc, single-paddle, sheet paddle, propeller, frame paddle, or anchor paddle. The stirring conditions are 40-50℃, 500-800rpm, and 1-5h.
10. The use of the curing agent microcapsule aqueous copolymer emulsion according to any one of claims 1-6 in the fields of coatings, wood, leather fabrics, adhesives or electronics industries.