CN111910440B

CN111910440B - Formula for cracking foam coating and fabric with cracking foam coating

Info

Publication number: CN111910440B
Application number: CN202010782264.2A
Authority: CN
Inventors: 陈龙
Original assignee: Andanda Industrial Technology Shanghai Co ltd
Current assignee: Andanda Industrial Technology Shanghai Co ltd
Priority date: 2020-08-06
Filing date: 2020-08-06
Publication date: 2021-07-09
Anticipated expiration: 2040-08-06
Also published as: CN111910440A

Abstract

The invention provides a formula for a coating with a cracking foaming coating, which is characterized by comprising B type latex for forming the cracking foaming coating, wherein the B type latex comprises a film forming agent, a surfactant and/or a foam stabilizer, a thickening agent and a cracking auxiliary agent; the film forming agent comprises one or more of butyronitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex and natural latex. The invention also provides a fabric with a cracked foam coating, wherein the fabric with the cracked foam coating comprises the following components in parts by weight: a base coat layer which prevents liquid from penetrating into the fabric; and a top coat disposed on at least a portion of the base coat, the top coat being a cracked foam coat. The formula provided by the invention can be used for preparing a coating of a cracking foaming coating with certain friction resistance and wear resistance. The fabric with the cracked foam coating has good gripping performance and is soft and comfortable. The preparation method does not produce a large amount of harmful waste water and is very environment-friendly.

Description

Formula for cracking foam coating and fabric with cracking foam coating

Technical Field

The invention relates to the field of high-performance composite materials, in particular to a formula of a coating with a cracking foaming coating and a fabric with the cracking foaming coating.

Background

Generally, coatings are applied to fabrics to impart specific characteristics to the fabric, such as increased frictional resistance of the surface, increased abrasion resistance, resistance to water and oil chemical solvents, and the like.

In the prior art, the following three methods are often used to apply the coating: direct coating methods, transfer coating methods, and coagulation coating methods; of these three methods, the solidified coating method is most widely used. The disadvantages of these three techniques include: for the direct coating method, because the coating is directly coated on the fabric by blade, a large amount of coating permeates into the fabric, the fabric is rigid, the comfort in use is poor, and effective water, oil and chemical solvents can not be achieved; for the transfer coating method, because the coating is adhered to the fabric by glue, the problems of peeling, poor wear resistance and the like are easy to occur after the coating is used; for the solidified coating method, the coating is usually solidified by using an aqueous solution of about 25% DMF, and then the DMF in the coating is replaced by using a water washing bath, so that the content of the DMF is reduced to be lower than 1%; such a methodThe coatings obtained are not effective against water, oil and chemical solvents, and most seriously, this method generates a large amount of harmful waste water (300 m)³Harmful wastewater/day, about 300 tons of products are produced every day), which contains a large amount of DMF, has higher concentration of organic pollutants, COD concentration reaches more than 4000mg/L, BOD5 concentration reaches more than 3000mg/L, and ammonia nitrogen concentration reaches 300 mg/L. This waste water needs to be concentrated to a special waste water treatment facility for treatment, which in turn results in a large amount of energy consumption.

In addition, conventional protective gloves made with the above fabrics have low grip or poor abrasion resistance or poor liquid penetration resistance in wet environments, oily and chemical solvent environments.

Disclosure of Invention

In order to solve some defects in the prior art, the invention firstly provides a formula for a coating with a cracking foaming coating, which is characterized in that the formula comprises a B type latex for forming the cracking foaming coating, wherein the B type latex comprises a B type film forming agent, a surfactant and/or a foam stabilizer, a thickening agent and a cracking auxiliary agent; the B type film forming agent comprises one or more of butyronitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex and natural latex; the pH value of the B type latex is 8-10.

Secondly, the invention also provides a fabric with a cracked foam coating, which is characterized by comprising the following components in parts by weight:

a base coat layer which prevents liquid from penetrating into the fabric; and

a top coat over at least a portion of the base coat, the top coat being a cracked foam coat.

The formula of the coating with the cracked foaming coating provided by the invention can prepare the coating with certain frictional resistance and wear resistance, so that the coating is provided for parts needing higher frictional resistance and wear resistance in a protective product, and the coating can be widely used for protective gloves and parts of protective appliances which are easy to wear, such as knee joints and elbow joints.

In addition, the fabric with the cracked foaming coating has the advantages that the surface of the fabric has high friction resistance and wear resistance, and the coating has good liquid permeation prevention performance; the high performance fabric can be used in a wide variety of applications in both production and life, for example, in protective equipment (e.g., protective clothing, protective gloves, protective helmets, etc.), protective gear. For example, when the fabric is used to make gloves, it has excellent gripping properties in a humid environment, an oily environment, and an environment of chemical solvents, due to the high frictional properties of the cracked surface. In a preferred embodiment, the fabric is not stiff, has better softness and is comfortable to use due to the penetration of the primer coating into a portion of the fabric; in addition, the coating is firmly combined with the fabric and is not easy to fall off.

Moreover, compared with the prior art, the coating prepared by the preparation method of the application does not generate a large amount of harmful wastewater, and only generates a small amount of common wastewater (30 m)³Ordinary wastewater/day, about 300 tons of product produced per day), this wastewater (COD: less than 1600mg/L and BOD less than 1500mg/L) is common industrial wastewater without special recovery treatment. Therefore, the method is very environmentally friendly.

Drawings

FIG. 1 is a micrograph of a cracked foam coated surface provided by the present invention.

Fig. 2 is a longitudinal cross-sectional micrograph of a fabric having a cracked foam coating provided by the present invention.

FIG. 3 is a schematic view of a glove having a cracked foam coating according to the present invention.

FIG. 4 is a schematic view of a preferred spray apparatus for spraying the type B coagulant.

FIG. 5 is a schematic view of a spray head body of a preferred spray coating device.

FIG. 6 is a schematic view of the internal structure of the nozzle body of the preferred spray coating device.

Detailed description of the preferred embodiments

The invention provides a formula for a coating with a cracking foaming coating, which is characterized by comprising B type latex for forming the cracking foaming coating, wherein the B type latex comprises a B type film forming agent, a surfactant, a thickening agent and a cracking auxiliary agent; the B type film forming agent comprises one or more of butyronitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex and natural latex; preferably, the pH of the type B latex is between 8 and 10.

In the B type latex, the B type film forming agent is a main component, the content of the B type film forming agent accounts for 70-90 wt% of the B type latex, and the total weight of all the components of the B type latex is 100%.

By adopting the formula, a cracked foam coating with proper friction resistance can be prepared.

The pH of the B-type latex may be adjusted by using a conventional alkaline solution, for example, a potassium hydroxide solution, a sodium hydroxide solution, ammonia water, or the like. Maintaining the pH within the preferred range helps stabilize the latex.

In order to prepare the foaming latex with a certain foam density so as to form a foaming coating with a proper foam density, the viscosity of the B-type latex is preferably 1000-2000 mpa.s.

In order to obtain a proper cracking effect, the cracking aid can be one or more of cracking resin, polyurethane emulsion, polymethyl acrylate emulsion, water-based alkyd resin, styrene-butadiene latex and phenolic resin; and more preferably, the amount of the cracking aid is 1 to 15 wt% based on the total weight of the B-type latex.

In order to obtain a suitable number and depth of cracks, preferably, the cracking resin includes acrylic cracking resin and/or urethane cracking resin; and further preferably, the amount of the crazing resin is 3 to 10% by weight based on the total weight of the B-type latex.

The B-latex may also include pigments, for example, pigments of various colors, such as TiO₂And a black pigment.

To facilitate foaming of the type B latex, in one embodiment, the type B latex further comprises a foaming powder; when high temperature is encountered, the volatile matter in the microcapsule in the foaming powder expands to play a role of foaming. In another embodiment, the type B latex does not include a foaming powder, and the type B latex is formed into a foamed latex by charging a compressed gas prior to applying the type B latex.

In order to obtain better cracking effect, the formula provided by the invention also comprises a B-type coagulant, wherein the B-type coagulant comprises one or more of the following salt solutions: one or more of calcium nitrate solution, calcium chloride solution, calcium acetate solution, magnesium nitrate solution, magnesium chloride solution, magnesium acetate solution, aluminum nitrate solution, aluminum chloride solution and aluminum acetate solution; the solvent in the B-type coagulant is one or more of water, methanol, ethanol, isopropanol, toluene and xylene; or the B-type coagulant comprises an acidic solution, and the acid is one or more of nitric acid, hydrochloric acid, acetic acid and stearic acid; the acidic solution may include one or more of water, methanol, ethanol, isopropanol, toluene, and xylene. Further preferably, in the B-type coagulant, the concentration of the salt solution is 20 to 60 wt%, preferably 25 to 50 wt%; alternatively, the concentration of the acid in the B-type coagulant is 5 to 20% by weight, preferably 5 to 10% by weight.

In one embodiment, the B-type coagulant can also comprise one or more of a surfactant and a defoaming agent to obtain better coagulation effect; the addition amount is, for example, 0.05 to 0.3% by weight based on the total weight of the type B coagulant.

Vulcanization is very important for some type B film formers, such as nitrile latex, in order to achieve a better hardness of the cracked foam layer. In one embodiment, the type B latex includes a vulcanizing agent, which may be a vulcanizing agent commonly used in the art, but for better vulcanization, preferably the vulcanizing agent is a sulfur dispersion; and further preferably, the amount of the vulcanizing agent is 0.5 to 2% by weight, based on the total weight of the type B latex.

In order to obtain better vulcanization effect, the B-type latex comprises an active agent, wherein the active agent is preferably one or more of zinc oxide, magnesium oxide and calcium oxide; and further preferably, the amount of the active agent is 1 to 5% by weight, based on the total weight of the type B latex.

Better vulcanization effect is obtained, and the B type latex comprises an accelerant, and the accelerant is preferably a rubber accelerant ZDEC, a rubber accelerant ZDBC, a rubber accelerant M, a rubber accelerant DM and a rubber accelerant PZ; preferably, the accelerator is present in an amount of 0.5 to 2 weight percent, based on the total weight of the type B latex.

The surfactant may be a surfactant conventional in the art, preferably sodium lauryl sulfate in order to provide a suitable surface tension to maintain a foam that does not break easily; the foam stabilizer may be a film stabilizer conventional in the art, preferably BASF a-18; preferably, the surfactant and/or foam stabilizer is present in an amount of from 0.1 to 1 weight percent, based on the total weight of the type B latex.

The thickening agent can be conventional thickening agent in the field, and in order to further stabilize the foam, preferably, the thickening agent is one or more of sodium carboxymethyl cellulose, hydroxyethyl cellulose, sodium polyacrylate, polyurethane, reducing adhesive and bentonite; further preferably, the amount of the thickener is 1 to 10% by weight, based on the total weight of the B-type latex.

To further improve abrasion resistance, the B-type latex further comprises an anti-abrasion agent, which may include, for example, polyethylene wax; preferably, the amount of said living abrasion resistant agent is from 1 to 5 weight percent based on the total weight of said type B latex.

In one embodiment, the type B latex further comprises a filler and/or a crosslinking agent. The filler may be, for example, calcium stearate and the crosslinking agent may be a polyisocyanate. In order to make the coating waterproof and oilproof, the formula also comprises A type latex matched with B type latex, wherein the A type latex comprises an A type film forming agent, a vulcanizing agent, an active agent, an accelerant, a defoaming agent and a thickening agent; the A-type film forming agent comprises one or more of butyronitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex and natural latex; preferably, the type A latex has a pH of from 8 to 9; preferably, the viscosity of the A-type latex is 2500-.

In the A type latex, the A type film forming agent is a main component, the content of the A type film forming agent accounts for 85 to 95 weight percent of the A type latex, and the sum of the components is 100 percent.

In the type A latex, the vulcanizing agent, the active agent, the promoter and the thickening agent can be the same as the corresponding components in the type B latex, and the contents are similar. The pH value is adjusted in a manner similar to that of the B-type latex.

In order to remove foams in the type A latex, the added defoaming agent can be a defoaming agent commonly used in the field, and is preferably one or more of higher alcohol, polysiloxane, polyether modified silicone oil and lanolin; for example, defoaming agents DF-965, DF-38; further preferably, the amount of the defoamer is from 0.01 to 0.5 wt% based on the total weight of the type B latex.

The type a latex may also include pigments, for example, pigments of various colors, such as TiO2, black pigments.

In order to ensure that only a part of the type a latex penetrates into the fabric, the formulation further comprises a type a coagulant comprising one or more of the following salt solutions: one or more of calcium nitrate solution, calcium chloride solution, calcium acetate solution, magnesium nitrate solution, magnesium chloride solution, magnesium acetate solution, aluminum nitrate solution, aluminum chloride solution and aluminum acetate solution; the solvent in the A-type coagulant is one or more of water, methanol, ethanol, isopropanol, toluene and xylene. Further preferably, the salt solution of the type a coagulant has a concentration of 1 to 5 wt%.

In a preferred embodiment, the type a coagulant is a methanol solution of calcium nitrate and the type B coagulant is an aqueous solution of calcium nitrate.

The invention also provides a fabric with a cracked foam coating, which is characterized by comprising the following components in parts by weight:

a base coat layer which prevents liquid from penetrating into the fabric; and

In order to obtain better frictional resistance, the width of the cracks in the cracked foam coating is 1 to 4 mm, preferably 2 to 3 mm.

In order to further obtain better frictional resistance, the density of the cracks in the cracked foam coating is 10-120 cracks/cm²Preferably 40 to 100 cracks/cm²。

In order to further obtain better frictional resistance, the depth of the cracks in the cracking foam coating is 0.1-1 mm, preferably 0.3-0.8 mm.

In order to obtain better hardness and provide better wear resistance, the cracked foam coating has a density of 0.6kg/L to 0.9kg/L, preferably 0.7kg/L to 0.9 kg/L. For example, when the cracked foam coating has a density of about 0.80kg/L, there may be about 15 bubbles per square millimeter. The desired wear resistance is obtained by adjusting the density of the cracked foam coating. For example, where it is desired that the coated fabric have good abrasion resistance over 8000 cycles, the cracked foam coating may be about 0.8kg/L (e.g., the coated fabric may pass through EN388 standard 8000 cycles). The thickness of the cracked foam coating and the foam density can be adjusted to provide higher abrasion resistance (e.g., 15000 cycles or more can be performed under EN388 standard).

The primer layer may have a thickness of about 0.1 mm to 0.2 mm.

To further provide better abrasion resistance, at least one of the primer layer and the cracked foam coating layer comprises a nitrile latex, for example, at a concentration of 40% to 50%; or at least one layer of the bottom coating and the cracking foaming coating comprises one or more of butyronitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex and natural latex; preferably a nitrile latex.

In order to provide good bonding between the fabric and the base coat, it is preferable that a portion of the fabric is impregnated with the base coat.

The fabric of the invention is used for forming the parts of gloves and protective tools (such as helmets, knee pads, elbow pads and protective shoes) which are easy to wear and are impacted, thereby having better gripping power, gripping power and wear resistance.

Preferably, both the base coat and the rip foaming coating are applied to the palm area and/or finger area of the glove; in a preferred embodiment, both the base coat and the rip foaming coating are applied to the palm area and the finger area of the glove.

In one embodiment, the glove is a mechanical glove or a chemical protective glove.

In one embodiment, the fabric with a split foam coating is prepared by a method comprising:

a. applying a type a latex for forming an undercoat layer, the type a latex forming the undercoat layer after coagulation; the A-type latex comprises an A-type film forming agent, a vulcanizing agent, an active agent, an accelerant, a defoaming agent and a thickening agent; the A-type film forming agent comprises one or more of butyronitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex and natural latex; preferably, the type a latex has a pH of 8 to 9;

b. applying a type B latex for forming a cracked foam coating on at least a portion of the base coat, the type B latex comprising a type B film former, a surfactant and/or foam stabilizer, a thickener, and a cracking aid; the B type film forming agent comprises one or more of butyronitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex and natural latex; preferably, the pH of the type B latex is between 8 and 10; and

c. before the B-type latex is coagulated, spraying a B-type coagulant to ensure that the foamed latex is instantaneously coagulated and cracked.

In the art, the coagulant is generally applied by dipping, but the effect of cracking of the foamed latex is not satisfactory when the coagulant is applied by dipping. The inventor of the present application has unexpectedly found that the cracking effect of the foamed latex can be improved by the spraying method through continuous exploration. The cracked foamed latex layer can be obtained by spraying the B-type coagulant with some spraying equipment. But is preferably sprayed using a spraying apparatus designed by the inventors of the present application.

The spray coating device includes: the spray head device is fixed at the output end of the manipulator and comprises a spray head body, the spray head body is provided with a material cavity and a compressed air cavity, the downstream of the material cavity is provided with a contraction section with gradually reduced inner diameter, the compressed air cavity surrounds the material cavity and is arranged, the outlet end of the compressed air cavity extends beyond the outlet end of the material cavity along the flowing direction of the material in the material cavity, and the spray head body is provided with a spray opening on the first end wall formed by the outlet end of the compressed air cavity.

Specifically, the spraying equipment is shown in fig. 4-6, and comprises a manipulator 1 and a nozzle device, wherein the nozzle device is fixed at the output end of the manipulator, the nozzle device comprises a nozzle clamp 2 and a nozzle body 3, the nozzle body 3 is fixedly connected with the nozzle clamp 2, and the nozzle clamp 2 is fixedly connected with the output end of the manipulator 1.

The inside material chamber 33 and the compressed air chamber 32 that are equipped with of shower nozzle body 3, material chamber 33 downstream has the internal diameter and reduces the shrink section gradually, compressed air chamber 32 encircles the material chamber and arranges, and the exit end of compressed air chamber 32 extends beyond the exit end of material chamber along the direction that the material flows in the material chamber, and shower nozzle body 3 is equipped with the jet orifice on the first end wall 31 that the exit end of compressed air chamber formed, and first end wall 31 of shower nozzle body 3 has the indent district, the jet orifice is located on the indent district, as shown in fig. 2.

A thimble 35 extending along the direction of the material flowing in the material cavity is arranged in the material cavity 33, the thimble 35 has a blocking section with a radial size larger than the diameter of the outlet end of the material cavity, a bolt 34 is arranged at the second end of the spray head body 3, the length of a screw rod of the bolt 34 is larger than the wall thickness of a shell of the spray head body in threaded connection with the bolt, the screw rod of the bolt penetrates through the shell of the second end of the spray head body to enter the interior of the spray head body, and the fixed end of the thimble 35 is connected with the end part of the screw rod; the feed channel of the material chamber 33 is arranged at an angle to the outlet channel of the material chamber, preferably perpendicular to the outlet channel, as shown in fig. 3. The thimble 35 has a tapered section with a radial dimension that tapers in a direction from the plugging section to a free end with a diameter that is smaller than the diameter of the outlet end of the cavity.

In the preferred embodiment, the nozzle holder 2 is provided with a mixing chamber 21, a plurality of coating material pipelines 5 are communicated into the mixing chamber 21, and after the coatings are uniformly mixed in the mixing chamber 21, the coatings are communicated into a feeding channel of the material chamber 33 along a material conveying pipe 23 through an outlet of the mixing chamber 21. The spray head holder 2 simultaneously fixes and guides the flow direction of the compressed gas, which enters the spraying equipment through the pipeline 4, is guided by the spray head holder 2 and then is input into the compressed air chamber 32 through the air pipe 22.

Preferably, the B-type coagulant comprises one or more of the following salt solutions: calcium nitrate solution, calcium chloride solution, calcium acetate solution, magnesium nitrate solution, magnesium chloride solution, magnesium acetate solution, aluminum nitrate solution, aluminum chloride solution and aluminum acetate solution; the solvent in the A-type coagulant is one or more of water, methanol, ethanol, isopropanol, toluene and xylene; or the B-type coagulant comprises an acidic solution, and the acid is one or more of nitric acid, hydrochloric acid, acetic acid and stearic acid.

Preferably, in the type B coagulant, the concentration of the salt solution is 20 to 60% by weight, preferably 25 to 50% by weight; alternatively, the concentration of the acid in the B-type coagulant is 5 to 20% by weight, preferably 5 to 10% by weight.

In order to obtain better cracking effect, the pressure for spraying the B-type coagulant is preferably 0.1-0.9MPa, preferably 0.5-0.8 MPa; the spray distance is 10-50cm, preferably 20-40 cm.

In order to obtain a better cracking effect, preferably, the cracking aid is one or more of cracking resin, polyurethane emulsion, polymethyl acrylate emulsion, water-based alkyd resin, styrene-butadiene latex and phenolic resin; preferably, the cracking resin includes an acrylic cracking resin and/or a urethane cracking resin.

Preferably, the type B latex is made into a foamed latex having a predetermined foam density prior to application, such as by the addition of compressed air.

Preferably, the method further comprises applying a type a coagulant to the fabric prior to the step of applying the type a latex; the coating thus obtained has a relatively strong bonding force with the fabric.

Preferably, the A-type coagulant comprises one or more of the following salt solutions: calcium nitrate solution, calcium chloride solution, calcium acetate solution, magnesium nitrate solution, magnesium chloride solution, magnesium acetate solution, aluminum nitrate solution, aluminum chloride solution and aluminum acetate solution; the solvent in the A-type coagulant is one or more of water, methanol, ethanol, isopropanol, toluene and xylene.

Preferably, the salt solution of the type a coagulant has a concentration of 1 to 5 wt%.

Preferably, the type a coagulant is a methanol solution of calcium nitrate and the type B coagulant is an aqueous solution of calcium nitrate.

Preferably, the method further comprises, prior to the step of applying a type a coagulant, heating the fabric to be coated; preferably, the surface temperature of the fabric to be coated is brought to 40-60 ℃.

Preferably, after the fabric is applied with the type A coagulant, the type A latex is applied after being kept at 40-60 ℃ for 50-120 seconds; thus, a part of the A-type latex can be ensured to permeate into the fabric, so that the bonding force between the formed coating and the fabric is greatly enhanced, and the fabric keeps better softness.

Preferably, the method further comprises applying a type B coagulant to the basecoat prior to the step of applying the foamed latex; preferably, the type B coagulant is sprayed onto the primer layer. Therefore, the latex on the contact surface of the B-type latex and the A-type latex can be better ensured to be completely solidified before vulcanization, so that the formed cracking foaming layer is not easy to fall off.

Preferably, the method further comprises the step of vulcanizing after the type B latex is solidified, to further increase the hardness of the cracked foam layer, thereby increasing the abrasion resistance.

The fabric may be a material such as nylon, polyester, cotton, High Performance Polyethylene (HPPE), aramid, glass fiber, rayon, polypropylene (PP), basalt, spandex; the shape of the fabric may be planar (e.g., woven or knitted fabric) or three-dimensional (e.g., knitted glove).

Examples

Example 1: preparation of fabrics with cracked foam coatings

The formula 1 provided by the invention comprises the following components as shown in the following table 1:

TABLE 1

Firstly, cotton fabric is loaded into a conveyor belt, and the speed of the conveyor belt is adjusted to be 50 mm/s.

In the second step, the fabric is preheated to a surface temperature of 50 ℃.

In the third step, the preheated fabric is immersed in a type a coagulant for 80 seconds.

And fourthly, keeping the fabric soaked with the A-type coagulant at 50 ℃ for 80 seconds.

And step five, dipping the fabric dipped with the A type latex into the A type latex, and keeping for 80 seconds.

Sixthly, forming a bottom coating after the A-type latex is solidified; and spraying the B-type coagulant on the A-type latex coating by adopting the spraying equipment shown in figure 4, wherein the spraying distance is 20cm, the spraying pressure is 0.4Mpa, and the spraying time is 10 seconds.

Seventh, the fabric coated with the type B coagulant is dipped in type B latex (the type B latex is pre-charged with compressed air so that the number of bubbles is about 15 bubbles per square millimeter) for 80 seconds.

And eighthly, spraying the B-type coagulant on the B-type latex coating by adopting the spraying equipment shown in figure 4 when the B-type latex is not coagulated, wherein the spraying distance is 20cm, the spraying pressure is 0.4MPa, and the spraying time is 10 seconds.

And step nine, after the B-type latex is solidified, soaking the fabric into a leaching tank to remove water-soluble substances. The produced wastewater (COD: 1300mg/L and BOD less than 1200mg/L) contains very small amount of surfactant and cationic flocculant, and the amount of the produced wastewater is 0.1m³Per ton of product. And step ten, passing the filtered fabric through an oven, and vulcanizing for 80 minutes at the vulcanization temperature of 80 ℃.

The surface of the foamed coating having cracks obtained in example 1 was shown in FIG. 1, and the width of the cracks was about 1 to 2mm, the depth of the cracks was 0.2 to 0.3mm, and the number of cracks was about 70/cm²The surface was very rough, and the density of the foam coating was 0.82 kg/L.

Figure 2 shows a longitudinal cross-sectional micrograph of a fabric with a cracked foam coating prepared from example 1. Wherein B denotes a cracked foam coating, a denotes a base coating, and F denotes a cotton woven fabric, and it is apparent from the drawing that a part of the base coating is impregnated into the cotton woven fabric.

Example 2: preparation of gloves with cracked foam coating

The formulation 1 provided by the present invention has the components shown in table 1.

Firstly, the cotton glove is covered on a hand, a conveyor belt is arranged in the glove, and the speed of the conveyor belt is adjusted to be 200 mm/s.

Secondly, preheating the fabric to make the surface temperature of the cotton gloves reach 40 ℃.

And thirdly, soaking the preheated cotton gloves into the A-type coagulant for 2 seconds.

Fourthly, the cotton thread gloves soaked with the A-type coagulant are kept at 45 ℃ for 50 seconds.

Fifth, the fabric impregnated with the type a latex was knife coated with the type a latex for 5 seconds.

Seventhly, the cotton gloves coated with the type B coagulant are dipped into the type B latex (the type B latex is previously charged with compressed air so that the number of bubbles is about 15 per square millimeter) for 80 seconds.

And step eight, when the B-type latex is not solidified, spraying the B-type coagulant on the B-type latex coating by using the spraying equipment shown in figure 4, wherein the spraying distance is 20cm, the spraying pressure is 0.4Mpa, and the spraying time is 10 seconds.

And step nine, after the B-type latex is solidified, soaking the cotton gloves into a leaching tank to remove water-soluble substances. The produced wastewater (COD: 1300mg/L and BOD less than 1200mg/L) contains very small amount of surfactant and cationic flocculant, and the amount of the produced wastewater is 0.1m³Per ton of product.

And step ten, passing the filtered fabric through an oven, and vulcanizing for 60 minutes at the vulcanization temperature of 80 ℃.

FIG. 3 is a depiction of a glove with a split coating made in example 2Figure (a). Wherein the palm and fingers of the glove are partially coated with said split foam coating, designated C. The width of the crack is about 1-2mm, the depth of the crack is 0.2-0.3mm, and the number of cracks is about 70/cm²The surface was very rough, and the density of the foam coating was 0.82 kg/L.

Example 3: preparation of gloves with cracked foam coating

The formula 1 provided by the invention comprises the following components as shown in the following table 2:

TABLE 2

In the first step, the cotton glove was put on the hand and the speed of the conveyor was adjusted to 50 mm/s.

In the second step, the fabric is preheated to a surface temperature of 50 ℃.

Sixthly, forming a bottom coating after the A-type latex is solidified; and spraying the B-type coagulant on the A-type latex coating by adopting the spraying equipment shown in figure 4, wherein the spraying distance is 40cm, the spraying pressure is 0.7Mpa, and the spraying time is 10 seconds.

Seventh, the fabric coated with the type B coagulant is dipped in type B latex (the type B latex is pre-charged with compressed air so that the number of bubbles is about 10 bubbles per square millimeter) for 80 seconds.

And step eight, when the B-type latex is not solidified, spraying the B-type coagulant on the B-type latex coating by adopting the spraying equipment shown in figure 4, wherein the spraying distance is 40cm, the spraying pressure is 0.7Mpa, and the spraying time is 10 seconds.

And step nine, after the B-type latex is solidified, soaking the fabric into a leaching tank to remove water-soluble substances. The produced wastewater (COD: 1000mg/L and BOD less than 900mg/L) contains very small amount of surfactant and cationic flocculant, and the amount of the produced wastewater is 0.1m³Per ton of product.

And step ten, passing the filtered fabric through an oven, and vulcanizing for 50 minutes at the vulcanization temperature of 120 ℃.

The obtained cracking foaming layer has crack width of 1-2mm, crack depth of 0.1-0.2mm, and crack number of 120/cm²The surface is very rough, and the density of the foaming coating is 0.9 kg/L; furthermore, the glove is particularly soft and comfortable to wear.

Example 4: preparation of gloves with cracked foam coating

The formula 1 provided by the invention comprises the following components as shown in the following table 3:

TABLE 3

In the second step, the fabric is preheated to a surface temperature of 50 ℃.

Sixthly, forming a bottom coating after the A-type latex is solidified; and spraying the B-type coagulant on the A-type latex coating by adopting the spraying equipment shown in figure 4, wherein the spraying distance is 30cm, the spraying pressure is 0.6Mpa, and the spraying time is 10 seconds.

Seventh, the fabric coated with the type B coagulant is dipped in type B latex (the type B latex is pre-charged with compressed air so that the number of bubbles is about 13 bubbles per square millimeter) for 80 seconds.

And step eight, when the B-type latex is not solidified, spraying the B-type coagulant on the B-type latex coating by adopting the spraying equipment shown in figure 4, wherein the spraying distance is 30cm, the spraying pressure is 0.6Mpa, and the spraying time is 10 seconds.

And step nine, after the B-type latex is solidified, soaking the fabric into a leaching tank to remove water-soluble substances. The produced wastewater (COD: 1200mg/L and BOD less than 1000mg/L) contains very small amount of surfactant and cationic flocculant, and the amount of the produced wastewater is 0.1m³Per ton of product.

And step ten, passing the filtered fabric through an oven, and vulcanizing for 60 minutes at the vulcanization temperature of 100 ℃.

The obtained cracking foamed layer has crack width of 2-3mm, crack depth of 0.2-0.3mm and crack number of 50/cm²The surface was very rough, and the density of the foam coating was 0.8 kg/L.

Example 5: preparation of gloves with cracked foam coating

The formula 1 provided by the invention comprises the following components as shown in the following table 4:

TABLE 4

In the second step, the fabric is preheated to a surface temperature of 50 ℃.

And step nine, after the B-type latex is solidified, soaking the fabric into a leaching tank to remove water-soluble substances. The produced wastewater (COD: 1100mg/L and BOD less than 900mg/L) contains very small amount of surfactant and cationic flocculant, and the amount of the produced wastewater is 0.1m³Per ton of product.

The obtained cracking foaming layer has crack width of 1-2mm, crack depth of 0.1-0.2mm, and number of cracks of 115/cm²The surface was very rough, and the density of the foam coating was 0.9 kg/L.

And (3) performance testing:

the abrasion resistance of the gloves prepared in examples 2, 3, 4 and 5 and the commercial protective gloves used as a control were measured using the european standard EN388 for abrasion resistance, the penetration of the gloves using the european standard EN374 for penetration, and the grip performance using the following methods, respectively:

dry grip Performance test

The weight was placed at the load-bearing end of a grip tester (manufacturer: satra), and during the experiment, the palm grip was tested, using a load force with a total load of 6.5 kgf.

And opening a switch of the data acquisition unit to enable the equipment to enter a working state.

And opening the computer provided with the software corresponding to the data collector, and opening the software Shortcut by double clicking to ensure that the data collector is successfully connected with the computer.

Double-click opens the data analysis software Instacal.

Selecting a test type: dry environment.

The number of repetitions of the test was selected: 7.

wearing the glove, pulling the weight, clicking the START key of the Instacal software interface, and starting the test. After 7 data are collected, the software automatically gives the average value of the test results.

The maximum grip force (kgf) was recorded and the magnitude of this physical quantity represents how good the grip performance of the glove was measured. The smaller the value, the better the grip performance.

Oil grip Performance test and Wet Environment grip Performance test

The oily grip performance test and the wet grip performance test are similar to the overall procedure of the dry grip performance test. The difference is that the glove is not coated with lubricating oil or water for dry grip, whereas a certain amount of lubricating oil and water is previously coated on the palm side of the glove for oil grip test or wet environment grip performance test. During the test, the test type is selected to be an oily environment or a wet environment respectively.

The results of the abrasion resistance and grip performance tests are shown in table 5 below:

TABLE 5

The results of the liquid permeability testing are shown in table 6 below:

TABLE 6

As can be seen from table 5: the gloves provided by the present application with a split foam coating have a grip performance somewhat better than the comparative protective gloves, but have an abrasion resistance much higher than that of the comparative protective gloves and much higher than that of the european standard (> 8000).

As can be seen from table 6: the ability of the gloves provided by the present application to prevent liquid penetration is also far superior to that of commercially available protective gloves. The permeation times for the various liquids are substantially above level 2, that is to say can be used substantially for the operation of the various liquids tested.

Claims

1. A composition for a coating having a cracked foam coating, the composition comprising:

the B type latex is used for forming a cracking foaming coating and comprises a B type film forming agent, a surfactant and/or a foam stabilizer, a thickening agent and a cracking auxiliary agent; the B type film forming agent comprises one or more of butyronitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex and natural latex; the composition also comprises a B-type coagulant, wherein the B-type coagulant comprises one or more of the following salt solutions: one or more of calcium nitrate solution, calcium chloride solution, calcium acetate solution, magnesium nitrate solution, magnesium chloride solution, magnesium acetate solution, aluminum nitrate solution, aluminum chloride solution and aluminum acetate solution; the solvent in the B-type coagulant is one or more of water, methanol, ethanol and isopropanol; or the B-type coagulant comprises an acidic solution, and the acid is one or more of nitric acid, hydrochloric acid, acetic acid and stearic acid;

the composition also comprises A type latex, wherein the A type latex comprises an A type film forming agent, a vulcanizing agent, an active agent, an accelerator, a defoaming agent and a thickening agent; the A-type film forming agent comprises one or more of butyronitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex and natural latex; wherein, the composition also comprises an A-type coagulant, and the A-type coagulant comprises one or more of the following salt solutions: one or more of calcium nitrate solution, calcium chloride solution, calcium acetate solution, magnesium nitrate solution, magnesium chloride solution, magnesium acetate solution, aluminum nitrate solution, aluminum chloride solution and aluminum acetate solution; the solvent in the A-type coagulant is one or more of water, methanol, ethanol and isopropanol;

the cracking auxiliary agent is cracking resin, and the cracking resin is acrylic cracking resin and/or polyurethane cracking resin.

2. The composition of claim 1, wherein the amount of crazing resin is from 1 to 15 weight percent, based on the total weight of the B-type latex.

3. The composition of claim 2, wherein the amount of crazing resin is from 3 to 10 weight percent, based on the total weight of the B-type latex.

4. The composition of claim 1, wherein the film former is present in an amount of 70 to 90 weight percent, based on the total weight of the type B latex.

5. The composition of claim 1, wherein in the type B coagulant, the concentration of salt solution is 20-60 wt%; alternatively, the concentration of the acid in the B-type coagulant is 5 to 20% by weight.

6. The composition of claim 1, wherein in the type B coagulant, the concentration of salt solution is 25-50 wt%; alternatively, the concentration of the acid in the B-type coagulant is 5 to 10% by weight.

7. The composition of claim 1, wherein the type B latex further comprises an accelerator comprising one or more of rubber accelerator ZDEC, rubber accelerator ZDBC, rubber accelerator M, rubber accelerator DM, and rubber accelerator PZ.

8. The composition of claim 7, wherein the accelerator is present in an amount of 0.5 to 2 weight percent, based on the total weight of the type B latex.

9. The composition of claim 7, wherein the type B latex further comprises a vulcanizing agent that is a sulfur dispersion.

10. The composition according to claim 9, wherein the vulcanizing agent is present in an amount of 0.5 to 2% by weight, based on the total weight of the type B latex.

11. The composition of claim 7, wherein the type B latex further comprises an active agent comprising one or more of zinc oxide, magnesium oxide, and calcium oxide.

12. The composition of claim 11, wherein the active agent is present in an amount of 1 to 5 wt%, based on the total weight of the type B latex.

13. The composition of claim 1, wherein the type B latex further comprises an anti-wear agent.

14. The composition of claim 13, wherein the amount of the anti-wear agent is 1-5 wt% based on the total weight of the B-type latex.

15. The composition of claim 1, wherein the type B latex further comprises a filler and/or a crosslinker.

16. The composition of claim 1, wherein the surfactant is sodium lauryl sulfate; the foam stabilizer is BASF A-18.

17. The composition of claim 1, wherein the surfactant and/or foam stabilizer is present in an amount of 0.1 to 1 weight percent, based on the total weight of the type B latex.

18. The composition of claim 1, wherein the thickener is one or more of sodium carboxymethylcellulose, hydroxyethylcellulose, sodium polyacrylate, polyurethane, vat gum, and bentonite.

19. The composition of claim 1, wherein the thickener is present in an amount of 1 to 10 weight percent, based on the total weight of the type B latex.

20. The composition of claim 1, wherein the type a latex has a pH of 8 to 9.

21. The composition as claimed in claim 1, wherein the type a latex has a viscosity of 2500-.

22. The composition of claim 1, wherein the film former is present in an amount of 85 to 95 weight percent, based on the total weight of the type a latex.

23. The composition of claim 1, wherein the salt solution concentration of the type a coagulant is 1-5 wt%.

24. The composition of claim 1, wherein the type a coagulant is a methanolic solution of calcium nitrate and the type B coagulant is an aqueous solution of calcium nitrate.

25. The composition of claim 1, wherein the type B latex has a pH of 8 to 10.

26. The composition as claimed in claim 1, wherein the viscosity of the B-type latex is 1000-2000 mpa.s.

27. A fabric having a cracked foam coating, the fabric having a cracked foam coating comprising:

a base coat layer which prevents liquid from penetrating into the fabric; and

a top coat over at least a portion of the base coat, the top coat being a cracked foam coat;

wherein the fabric with the cracked foam coating is prepared by the following method, and the method comprises the following steps:

a. applying a type a latex for forming an undercoat layer, the type a latex forming the undercoat layer after coagulation; the A-type latex comprises an A-type film forming agent;

b. applying a B type latex for forming a cracking foaming coating on at least one part of the bottom coating, wherein the B type latex comprises a B type film forming agent and a cracking auxiliary agent, and one or more of a surfactant and/or a foam stabilizer and a thickening agent; the B-type film forming agent comprises one or more of butyronitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex and natural latex; the cracking auxiliary agent is cracking resin, and the cracking resin is acrylic cracking resin and/or polyurethane cracking resin; and

c. before the B-type latex is solidified, spraying a B-type coagulant to ensure that the foamed latex is instantaneously solidified and cracked; wherein the B-type coagulant comprises one or more of the following salt solutions: calcium nitrate solution, calcium chloride solution, calcium acetate solution, magnesium nitrate solution, magnesium chloride solution, magnesium acetate solution, aluminum nitrate solution, aluminum chloride solution and aluminum acetate solution; the solvent in the B-type coagulant is one or more of water, methanol, ethanol and isopropanol; or the B-type coagulant comprises an acidic solution, and the acid is one or more of nitric acid, hydrochloric acid, acetic acid and stearic acid.

28. The fabric having a crazing foamed coating according to claim 27, wherein the width of the cracks in the crazing foamed coating is 1-4 millimeters.

29. The fabric having a crazing foamed coating according to claim 27, wherein the width of the cracks in the crazing foamed coating is 2-3 millimeters.

30. The fabric having a cracked foam coating of claim 27, wherein the density of cracks in the cracked foam coating is10-120 cracks/cm²。

31. The fabric having a split foam coating of claim 27, wherein the density of cracks in the split foam coating is 40-100 cracks/cm²。

32. The fabric having a crazing foamed coating according to claim 27, wherein the depth of the cracks in the crazing foamed coating is from 0.1 to 1 millimeter.

33. The fabric having a crazing foamed coating according to claim 27, wherein the depth of the cracks in the crazing foamed coating is from 0.3 to 0.8 millimeters.

34. The fabric having a cracked foam coating of claim 27, wherein the cracked foam coating has a density of from 0.6kg/L to 0.9 kg/L.

35. The fabric having a cracked foam coating of claim 27, wherein the cracked foam coating has a density of from 0.7kg/L to 0.9 kg/L.

36. The fabric having a cracked foam coating of claim 27, wherein the primer coating comprises one or more of nitrile latex, polyurethane emulsion, polyacrylic emulsion, neoprene latex, and natural latex.

37. The fabric having a split foamed coating of claim 27, wherein a primer layer penetrates a portion of the fabric.

38. The fabric having a cracked foam coating of claim 27, wherein the fabric is used to form a glove, protective gear, or an abradable portion.

39. The fabric having a rip foaming coating according to claim 38, wherein the base coat and the rip foaming coating are both applied to the palm area and/or the finger area of the glove.

40. The fabric having a split foam coating of claim 38, wherein the glove is a mechanical glove or a chemical protective glove.

41. The fabric having a cracked foam coating of claim 27, wherein the type a latex has a pH of 8-9.

42. The fabric having a cracked foam coating of claim 27, wherein the type B latex has a pH of from 8 to 10.

43. The fabric with a cracked foam coating of claim 27, wherein in the type B coagulant, the salt solution is at a concentration of 20-60% by weight; alternatively, the concentration of the acid in the B-type coagulant is 5 to 20% by weight.

44. The fabric with a cracked foam coating of claim 27, wherein in the type B coagulant, the salt solution is in a concentration of 25-50% by weight; alternatively, the concentration of the acid in the B-type coagulant is 5 to 10% by weight.

45. The fabric with a cracked foam coating of claim 27, wherein the pressure at which the type B coagulant is sprayed is 0.1-0.9 MPa; the spraying distance is 10-50 cm.

46. The fabric with a cracked foam coating of claim 27, wherein the pressure at which the type B coagulant is sprayed is 0.5-0.8 MPa; the spraying distance is 20-40 cm.

47. The fabric having a cracked foam coating of claim 27, wherein the type B latex is made into a foamed latex having a predetermined foam density prior to application.

48. The fabric having a split foamed coating according to claim 27, wherein the method further comprises applying a type a coagulant to the fabric prior to the step of applying the type a latex.

49. The fabric with a split foamed coating of claim 48, wherein the type A coagulant comprises one or more of the following salt solutions: calcium nitrate solution, calcium chloride solution, calcium acetate solution, magnesium nitrate solution, magnesium chloride solution, magnesium acetate solution, aluminum nitrate solution, aluminum chloride solution and aluminum acetate solution; the solvent in the A-type coagulant is one or more of water, methanol, ethanol and isopropanol.

50. The fabric with a split foamed coating of claim 49, wherein the salt solution concentration of the type A coagulant is 1-5% by weight.

51. The fabric with a split foamed coating of any one of claims 48 to 50, wherein the type A coagulant is a methanol solution of calcium nitrate and the type B coagulant is an aqueous solution of calcium nitrate.

52. The fabric with a split foamed coating of any one of claims 48-50, wherein the method further comprises heating the fabric to be coated prior to the step of applying the type A coagulant.

53. The fabric having a split foamed coating of claim 52, wherein the surface temperature to which the fabric is heated to be coated is 40-60 ℃.

54. The fabric having a cracked foam coating of claim 48, wherein the type A latex is applied after the fabric has been held at 40-60 ℃ for 50-120 seconds after the type A coagulant is applied to the fabric.

55. The fabric having a split foamed coating according to any one of claims 27 to 50, wherein the method further comprises applying a type B coagulant to the base coating prior to the step of applying the foamed latex.

56. The fabric having a cracked foam coating of claim 55, wherein the type B coagulant is sprayed onto the primer layer.