KR20160010568A - Preparation of pressure sensitive adhesive dispersions from multi-stage emulsion polymerization for applications of protective films - Google Patents

Abstract

The present invention describes a process for producing a pressure-sensitive adhesive comprising multi-stage emulsifier-free polymerization and application of the obtained dispersion for a pressure-sensitive protective film. One or more carboxylic acid group-containing monomers are used in the first step of the emulsion polymerization. The theoretical glass transition temperature is lower than 0 ° C (for the first stage polymer), -20 ° C (for the second stage polymer), and -15 ° C (for the total dispersion). The dispersion is preferably crosslinked by a multifunctional crosslinking agent such as aziridine, isocyanate, carbodiimide and oxazoline. The adhesive obtained from the method can be used for the application of a protective film to reduce or eliminate ghost shadows on the protected surface.

Description

Preparation of Pressure Sensitive Adhesive Dispersions from Multi-Stage Emulsion Polymerization for the Application of Protective Films BACKGROUND OF THE INVENTION < RTI ID = 0.0 > [0001] < / RTI &

The present invention relates to a process for producing a pressure-sensitive adhesive dispersion. More particularly, the present invention relates to a process for producing a pressure-sensitive adhesive dispersion for protecting a surface by multi-stage emulsion polymerization, and a pressure-sensitive adhesive dispersion prepared therefrom.

Protective films are used to temporarily protect the surface of the product or product from scratches or contamination, which can be used for surface protection and industrial processing of the final product before use. The adhesion strength to a protected surface may vary to meet the requirements of various applications, but in most implementations one common standard is shared. That is, when the protective film is removed, no residue should remain on the protected surface. Residues from the adhesive on the protected surface can cause a "ghost shadow ", commonly referred to as" ghosting "or" shadow ".

"Gasting" can occur in hot melt, solvent based and polymer dispersion adhesive, which may be due to small molecules, oligomers or low molecular weight short chain polymers, although this is not very certain. In some special applications, "ghost shadows" becomes a problem, especially when a protective film is used on a glossy surface.

In recent years, scientists in the field have been working hard to find ways to reduce or avoid "ghost shadows." For example, cross-linking of the adhesive can help reduce ghosting. Nevertheless, additional chemical or physical means must be applied to inhibit the transfer of low molecular weight paper to the protected surface. Since conventional adhesive dispersions are generally prepared from emulsion polymerization using emulsifiers (surfactants) or stabilized with low molecular weight protective colloids, protective film adhesives made from such dispersions can not even have a certain degree of cross-linking The ghost shadow problem almost can not be avoided.

WO2011 / 154920A1 discloses a process for producing an aqueous polymer dispersion for producing a composite film by multi-stage emulsion polymerization. Its purpose was to prepare aqueous polymer dispersions that could be used to prepare composite films with very good instantaneous adhesion and very good thermal stability. WO2011 / 154920A1 does not address the "ghost shadows" problem of protective films.

US2011 / 0077030A1 discloses a multi-stage emulsion polymerization preparation of an aqueous pressure-sensitive adhesive dispersion for the manufacture of self-adhesive products. Its object was to provide an aqueous PSA dispersion which has as little emulsifier content as possible, has good adhesion and tackiness and forms as little coagulum as possible. US2011 / 0077030A1 does not have the effect of avoiding ghost shadows and adhesive residues on metal surfaces.

WO2012 / 038202A1 discloses a process for preparing an aqueous pressure-sensitive adhesive dispersion through multi-stage free-radical emulsion polymerization. The aqueous pressure-sensitive adhesive dispersions obtained can be used in the production of self-adhesive articles, in particular self-adhesive labels and adhesive tapes. WO2012 / 038202A1 is not intended to avoid "ghost shadows" on protective films.

CN200610077426.2 discloses a pressure-sensitive adhesive which can be easily removed from the pressure-sensitive surface without severe ghosting and exhibits excellent wet-out and is easily and inexpensively manufactured. However, CN200610077426.2 does not relate to a method for producing a pressure-sensitive adhesive through multi-stage emulsion polymerization, and the pressure-sensitive adhesive of CN200610077426.2 is completely different from the pressure-sensitive adhesive obtained in the present invention.

Protective colloids prepared in situ from multi-stage emulsion polymerization are promising solutions to reduce or eliminate ghost shadows because 1) no emulsifier is used during polymerization, 2) the molecular weight and action of the protective colloid produced therefrom Since the temperature can be easily controlled and adjusted for further processing or modification.

Functional groups incorporated into the dispersion through copolymerization of functional monomers, such as carboxylic acid groups and hydroxyl groups, provide many flexibility in adjustable crosslinking degrees as well as different crosslinking mechanisms. These functional groups can be used as a two-component crosslinking system in combination with a multifunctional crosslinking agent, for example, aziridine, isocyanate, oxazoline and carbodiimide. The pressure-sensitive adhesive dispersion obtained from such emulsifier-free multi-stage emulsion polymerization is provided to solve the "ghost shadow" problem for the protective film.

The present invention provides a process for producing a pressure-sensitive adhesive dispersion by multi-stage emulsion polymerization. The protective film coated with the pressure-sensitive adhesive dispersion of the present invention can be applied to the surface of the protective film by a "ghost " on the protected surface when removed from the protected surface, through the reduced amount of low molecular weight species in the adhesive, Shadow "can be avoided. The process of the present invention comprises the steps of: (a) preparing a protective colloid in a first stage of emulsion polymerization, wherein no additional emulsifier is used during this stage; (b) a second stage of emulsion polymerization, , Wherein the polymer obtained from the emulsion polymerization contains a functional group that can be crosslinked during the coating and drying process when the pressure-sensitive adhesive is formed, and preferably (c) a polymer obtained from the emulsion polymerization Crosslinking the polymer with a cross-linking agent.

The pressure-sensitive adhesive dispersion obtained from the method of the present invention successfully avoids "ghost shadows" on the protected surface. For example, in one embodiment of the present invention, the pressure-sensitive adhesive dispersion of the present invention or the pressure-sensitive adhesive from the pressure-sensitive adhesive formulation of the present invention exhibits excellent adhesion as well as excellent adhesion to the polyethylene film, And the occurrence of adhesive transfer, thereby eliminating adhesive residues on the stainless steel surface.

In another embodiment of the present invention, there is no visible ghost shadow on the stainless steel surface after the protective film of the present invention is removed, wherein the protective film of the present invention comprises a film of the pressure-sensitive adhesive dispersion Or by applying pressure-sensitive adhesive formulations.

In general, the present invention relates to a process for preparing a pressure-sensitive adhesive dispersion through multi-stage emulsion polymerization.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

The singular representation used to define a term includes both the plural and singular forms of the term.

"Ethylenically unsaturated monomer" when used in the present invention means monoethylenically unsaturated monomer.

In the present invention, the term "ethylenically unsaturated monomer" is, in use, irrelevant to the term " carboxylic acid group-containing ethylenically unsaturated monomer of the present invention ".

In a first aspect of the present invention,

1) A process for producing a first-stage dispersion comprising: (i) obtaining a first-stage polymer particle from a first-stage monomer composition consisting of an ethylenically unsaturated monomer and at least one ethylenically unsaturated monomer containing a carboxylic acid group in an aqueous medium to form a first- Wherein the carboxylic acid group-containing ethylenically unsaturated monomer is contained in an amount of at least 1.0 wt% (preferably 10 to 30 wt%) of the first stage monomer composition;

(ii) adding a chain transfer agent to the first-step monomer composition, wherein the addition amount of the chain transfer agent is 0.3 to 1.5% by weight, preferably 0.3 to 1.1% by weight; And

(iii) neutralizing the first-stage dispersion with an aqueous base solution to a pH value of 5.0 to 7.0, preferably 6.0 to 7.0

A first emulsion polymerization step comprising:

2) in the presence of a neutralized first stage dispersion, a second stage monomer composition consisting of an ethylenically unsaturated monomer and optionally one or more multi-ethylenically unsaturated monomers is polymerized into said first stage polymer particles to form second stage polymer particles , Thereby obtaining a pressure-sensitive adhesive dispersion, a second emulsion polymerization step

Wherein the weight ratio of the first stage monomer composition to the total amount of the first stage monomer composition and the second stage monomer composition is 5 to 50 wt%, preferably 8 to 30 wt%, e.g., 10 To 20% by weight,

To a process for producing a pressure-sensitive adhesive dispersion.

Without wishing to be bound by any theory, it is believed that in the first stage of emulsion polymerization, the first stage monomer composition forms first stage polymer particles and then, in a second stage of emulsion polymerization, the second stage monomer composition It is believed that they are polymerized into the first stage polymeric particles to form the pressure sensitive adhesive dispersion of the present invention.

The multi-stage emulsion polymerization of the present invention takes place in an aqueous medium, and no emulsifier is used. In the first step of emulsion polymerization, the ethylenically unsaturated monomer containing a carboxylic acid group is copolymerized with an ethylenically unsaturated monomer in the first-stage monomer composition to form a first-stage polymer particle having an acid group. When these acid groups are neutralized at a pH higher than 7.0, for example, a pH value of 5.0 to 7.0, preferably 6.0 to 7.0, the hydrophilicity of the first-stage polymer particles is increased, It will act as a colloid, and at the end of polymerization, a polymer dispersion with a high solids content will be able to be stabilized. The number average molecular weight of the obtained protective colloid is in excess of 2000 g / mol, preferably in the range of 10,000 to 50,000 g / mol.

Preferably, in the multi-stage emulsion polymerization of the present invention, seed particles are contained in the initial load for the first stage of the emulsion polymerization to precisely control the size of the polymer particles. For example, in this first step, a seed dispersion, such as a polystyrene seed dispersion, can be included in the initial load of the polymerization reactor to better control the particle size of the resulting dispersion.

In the pressure-sensitive adhesive dispersion of the present invention, the weight ratio of the first-stage monomer composition to the total amount of the first-stage monomer composition and the second-stage monomer composition is 5 to 50 wt%, preferably 8 to 30 wt% 10 to 20% by weight.

Suitable ethylenically unsaturated monomers for the first stage monomer composition include, but are not limited to, (meth) acrylates with / without functional groups (e.g., 2-ethylhexyl acrylate, butyl acrylate, ethyl acrylate, methyl Acrylate, methyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, ureido methacrylate, glycidyl methacrylate, acetoacetoxyethyl methacrylate, hydroxypropyl carbamate Acrylate and SIPOMER (trade name) β-CEA (from Solvay Rhodia, Singapore), vinyl and allyl monomers with / without functional groups (eg styrene, vinyl acetate, (VeoVa) 9 (from Momentive, Ghana, Ohio), Veova < (R) > 10 BASF SE from Ludwigshafen, Germany), < RTI ID = 0.0 > Bovas < / RTI > EH (from Momentiv, Ghana, Ohio), Golpanol VS (From Solvay Rhodia, Singapore), SEPHORM (trade name) COPS-I (from Solvay Rhodia of Singapore), SEPHORM (trade name) AAE-10 (From Solvay Rhodia, Singapore), LATEMUL PD-420 (from Kaohsiung, Shanghai, China), and other functional ethylenically unsaturated monomers (e.g., (From Sigma-Aldrich, St. Louis, Mo.) and diacetone acrylamide (from Sigma-Aldrich, St. Louis, Mo.) (Saint, Missouri, USA) (From Sigma-Aldrich, Is.) (Coupled with adipic acid dihydrazide (from Sigma-Aldrich, St. Louis, Mo.) via addition of adipic acid dihydrazide to the final dispersion Or a combination thereof.

As mentioned above, in the process of the present invention, suitable monomers for the first stage monomer composition may be used in combination, and monomers suitable for the second stage monomer composition may be used in combination. For example, a combination of two or more monomers suitable for use as the ethylenically unsaturated monomer of the first stage monomer composition may be applied to the process of the present invention. The combination of different ethylenically unsaturated monomers can control the glass transition temperature of the copolymer to adjust the performance of the adhesive as well as provide functionalities to improve the functionality of the resulting dispersion. For example, there may be mentioned the following compounds: Sephomer (trade name) COPS-I, Sephomer (trade name) COPS-I, Sephomer (trade name) AAE- Merd PD-420, Lateral PD-450 and Golpanol (trade name) VS can be applied for excellent dispersion stability and can be used in combination with glycidyl methacrylate, N-methylol acrylamide and diacetone acrylamide Diphenylaid hydrazide) is applicable for cross-linking and is commercially available under the trade name of Veova® 9, Veova® 10, Veova® EH, Seomer® (trade name) PAM- 100 and ureido methacrylate are applicable to the resulting adhesive to provide specific properties later, for example, excellent water whitening resistance and high polarity for physical "crosslinking ". In one embodiment of the present invention, there is provided a process for the preparation of the compound of formula (I), which comprises the steps of: One or more of the monomers selected from the group consisting of CEA, Lateral PD-420, Lateral PD-450 and Golpanol (trade name) VS are commercially available under the trademarks Veova® 9, Veova® 10 , EVO (registered trademark) EH, Sephomer (trade name) PAM-100, and ureido methacrylate.

When diacetone acrylamide is used as the ethylenically unsaturated monomer in the present invention, adipic acid dihydrazide must be added to the pressure-sensitive adhesive dispersion obtained after the multi-stage emulsion polymerization of the present invention, In use, this means that in order to obtain the final pressure-sensitive adhesive dispersion, it must be combined with the adipic acid dihydrazide through addition of adipic acid dihydrazide to the dispersion.

Suitable ethylenically unsaturated monomer containing carboxylic acid groups for the first step monomer composition of the present invention may be selected from ethylenically unsaturated acid monomers and combinations thereof, such as acrylic acid, methacrylic acid, itaconic acid, and combinations thereof . The ethylenically unsaturated monomer containing at least one carboxylic acid group must be included in this step of the emulsion polymerization and the amount of the ethylenically unsaturated monomer containing at least one carboxylic acid group in the first step of the polymerization must be sufficient to ensure good dispersion stability and to provide sufficient functional groups for subsequent cross- , Preferably at least 1.0% by weight of the first stage monomer composition.

Suitable bases for the neutralization step in the first step of the emulsion polymerization may be aqueous inorganic bases, such as, but not limited to, one or a combination of sodium hydroxide, potassium hydroxide and ammonia water. At this stage, a high pH value may affect the efficiency of the initiator and a pH value of less than 7.0 is preferred.

A chain transfer agent is essential in the first step of emulsion polymerization. Suitable chain transfer agents may be, but are not limited to, one or combination of tertiary dodecylmercaptan and 2-ethylhexyl thioglycolate, and preferred amounts thereof are from 0.3 to 1.5 weight percent, based on the weight of the first stage monomer composition, %, Preferably from 0.3 to 1.1% by weight.

In the second stage of the emulsion polymerization, a second stage monomer composition is polymerized into the first stage polymer particles formed in the first stage of the emulsion polymerization.

Suitable ethylenically unsaturated monomers for the second stage monomer composition include, but are not limited to, (meth) acrylates having / without functional groups (e.g., 2-ethylhexyl acrylate, butyl acrylate, ethyl acrylate, methyl Acrylate, methyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, ureido methacrylate, glycidyl methacrylate, acetoacetoxyethyl methacrylate, hydroxypropyl carbamate Acrylate and SIPOMER (trade name) β-CEA, vinyl and allyl monomers with and without functional groups (eg styrene, vinyl acetate, Veova® 9, Veova® 10 (Trade name) AES-100), and another functional ethylene type (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.), BEPA (registered trademark) EH, Gopalol VS (trade name) Unfavorable (For example, Saporomer (trade name) PAM-100, Rothermal PD-420, Rothermal PD-450, N-methylol acrylamide and diacetone acrylamide (adipic acid dihydrate Lt; RTI ID = 0.0 > dihydrazide < / RTI >

The multi-ethylenically unsaturated monomers suitable for the second stage monomer composition may be selected from the group consisting of divinylbenzene, allyl methacrylate, diethylene glycol dimethacrylate, LaRomer (trade name) BDDA, trimethylolpropane trimethacrylate , And other multi-ethylenically unsaturated monomers.

In addition to multi-stage emulsion polymerization, water-soluble initiators such as thermal initiators and redox initiators such as sodium persulfate, potassium persulfate, ammonium persulfate, sodium acetone bisulfite / Tert-butyl hydroperoxide and sodium bisulfite / sodium persulfate may also be used.

The emulsion polymerization of the present invention can be carried out at any temperature suitable for emulsion polymerization, for example, at a temperature in the range of 65 to 95 캜, preferably 75 to 90 캜, more preferably 80 to 85 캜.

The pressure-sensitive adhesive dispersion prepared from the process of the present invention has a solids content of 40 to 56% and a pH value of 5.0 to 9.5. The average particle size of the polymer particles dispersed in the pressure-sensitive adhesive dispersion is adjustable within the range of 140 to 350 nm. In the present invention, the glass transition temperature of the first-stage polymer is lower than 0 ° C, the glass transition temperature of the second-stage polymer is lower than -20 ° C, and the glass transition temperature of the total dispersion polymer is lower than -15 ° C.

According to Fox (TG Fox, Bull. Am. Phys. Soc. 1956 [Ser. II] 1, page 123) and Ullmann's Encyclopadie der technischen Chemie, Volume 19, page 18, 4th Edition, Verlag Chemie, Weinheim, 1980) Fox equation is provided and the glass transition temperature of the polymer is calculated as an approximation of the following equation:

_{1 / Tg = x 1 / Tg} 1 + x 2 / Tg 2 +. . . x _n / Tg _n

Wherein x ₁ , x ₂ ,. . . x _n is the number of monomers 1, 2,. . . n, and Tg ₁ , Tg ₂ ,. . . T _n is the number of monomers 1, 2,. . . (in degrees Kelvin) of the polymer synthesized from only one of the n and n. The Tg values for the homopolymers of the major monomers are known and are described, for example, in Ullmann's Ecology of Industrial Chemistry, Vol. 5, Vol. A21, page 169, VCH Weinheim, 1992, and other sources of the glass transition temperature of the homopolymer are described, for example, in J. Am. Brandew, EH Immergut, Polymer Handbook, 1st Edition, J. Wiley, New York 1966, 2nd Edition, J. Wiley, New York 1975, and 3rd Edition, J. Wiley, New York 1989.

The present invention also relates to a pressure-sensitive adhesive dispersion prepared by the method of the present invention.

In another aspect of the present invention, the present invention is directed to a method of making a pressure-sensitive adhesive formulation comprising the step of adding a cross-linking agent to a pressure-sensitive adhesive dispersion prepared by the method of the present invention.

Optionally, in the method of this embodiment, one or more additional additives may be added, for example a humectant such as Lumiten (trade name) I-SC and a thickener. There is no particular requirement for such additional additives, provided that they can only be used for the purposes of the present invention.

In a preferred embodiment of the process for producing a pressure-sensitive adhesive formulation of the present invention, when the pressure-sensitive adhesive dispersion prepared from the process of the present invention has a pH value of less than 7.0, preferably a crosslinking agent is added to the pressure- , The process for producing a pressure-sensitive adhesive formulation of the present invention further comprises the step of neutralizing the pressure-sensitive adhesive dispersion prepared from the process of the present invention with a base to a pH value of more than 7.0, preferably less than 10 .

The base used for neutralization may be any base suitable for the purpose of the present invention, for example, ammonia water, potassium hydroxide and sodium hydroxide (preferably in the form of an aqueous solution).

In the production method of the pressure-sensitive adhesive formulation of the present invention, the crosslinking agent is added and mixed well into the pressure-sensitive adhesive dispersion of the present invention. Suitable crosslinking agents for the purposes of the present invention are those capable of reacting with the carboxylic acid or carboxylate in the polymer obtained by the multi-stage emulsion polymerization of the present invention. Preferably, the cross-linking agent is selected from the group consisting of polyfunctional aziridines, isocyanates, oxazolines, carbodiimides, and combinations thereof, such as Crosslinker (trade name) CX-100 (NeoResins), XAMA (product name) 7 (ICHEMCO srl, Cuzeno, Italy), Basonat (product name) DS 3582 (Ludwig- BASF SE), BASONAT (trade name) LR 9056 (BASF SEISE, Ludwigshafen, Germany), or HYCASYL (trade mark) 510 (Rhein Chemie, Mannheim, Germany). The amount of cross-linking agent suitable for the process of the invention theoretically corresponds to the amount of carboxylic acid or carboxylate in the polymer obtained by the multi-stage emulsion polymerization of the present invention. Preferably, the amount of cross-linking agent is from 0 to 10% by weight, preferably from 0 to 8% by weight, more preferably from 0.5 to 5% by weight, based on the total weight of the pressure-sensitive adhesive formulation of the present invention, 1 to 3% by weight.

The present invention also relates to a pressure-sensitive adhesive formulation obtained from a method of producing the pressure-sensitive adhesive formulation of the present invention.

In a further aspect, the invention relates to a pressure-sensitive adhesive dispersion of the invention or a substrate coated with the pressure-sensitive adhesive formulation of the present invention. The substrate may be any substrate suitable for applying an adhesive, and preferably the substrate is selected from the group consisting of a tape, a sheet, a film, a plate, etc. More preferably, to be.

Further, the present invention relates to the pressure-sensitive adhesive dispersion of the present invention or the use of the pressure-sensitive adhesive formulation of the present invention for producing a protective film.

The pressure-sensitive adhesive dispersion of the present invention obtained from the method of the present invention or the pressure-sensitive adhesive formulation of the present invention is successfully excluded from "ghost shadows ". For example, if a protective film coated with the inventive pressure sensitive adhesive dispersion obtained from the method of the present invention is applied to the surface of a stainless steel test panel under ambient conditions and severe aging conditions, the protective film may be removed from the film Do not create ghost shadows on the posterior surface, and there is no adhesive residue on the metal surface. The pressure-sensitive adhesive formulations of the present invention obtained from the process of the present invention also yield the same results.

In some preferred embodiments of the present invention, the physical properties, such as tact and peel strength, of the pressure-sensitive adhesive dispersion or pressure-sensitive adhesive formulations of the present invention can be improved by altering the combination of monomers (glass transition temperature Or by adjusting the molecular weight and / or degree of crosslinking in the polymerization step (by the multi-ethylenically unsaturated monomer) and in the formulation / coating process (by the external crosslinking agent).

In summary, the present invention relates to the following embodiments.

1. 1) obtaining a first-stage polymer particle from a first-stage monomer composition consisting of an ethylenically unsaturated monomer and at least one carboxylic acid group-containing ethylenically unsaturated monomer in an aqueous medium to form a first-stage dispersion, Wherein the carboxylic acid group-containing ethylenically unsaturated monomer is contained in an amount of at least 1.0% by weight (preferably 10 to 30% by weight) of the first-stage monomer composition;

(ii) adding a chain transfer agent to the first-step monomer composition, wherein the addition amount of the chain transfer agent is 0.3 to 1.5% by weight, preferably 0.3 to 1.1% by weight; And

(iii) neutralizing the first-stage dispersion with an aqueous base solution to a pH value of 5.0 to 7.0, preferably 6.0 to 7.0

A first emulsion polymerization step comprising:

2) in the presence of a neutralized first stage dispersion, a second stage monomer composition consisting of an ethylenically unsaturated monomer and optionally one or more multi-ethylenically unsaturated monomers is polymerized into said first stage polymer particles to form second stage polymer particles , Thereby obtaining a pressure-sensitive adhesive dispersion, a second emulsion polymerization step

Wherein the weight ratio of the first stage monomer composition to the total amount of the first stage monomer composition and the second stage monomer composition is 5 to 50 wt%, preferably 8 to 30 wt%, e.g., 10 To 20% by weight,

Sensitive adhesive agent dispersion.

2. A process according to embodiment 1, wherein a water-soluble initiator is used in the emulsion polymerization, and preferably the water-soluble initiator is a thermal initiator and a redox initiator such as sodium persulfate, potassium persulfate, ammonium persulfate, Sulfite / tert-butyl hydroperoxide, and sodium bisulfite / sodium persulfate.

3. The method of any one of embodiments 1 or 2, wherein the multi-ethylenically unsaturated monomer is used in an amount of 0.3 to 2.0 wt%, preferably 0.5 to 1.6 wt% of the second-stage monomer composition.

4. In any one of Embodiments 1 to 3,

Wherein the ethylenically unsaturated monomer of the first stage monomer composition is selected from the group consisting of (meth) acrylates with and without functional groups, vinyl and allyl monomers with / without functional groups, other functional ethylenically unsaturated monomers and combinations thereof Wherein the ethylenically unsaturated monomer of the first step monomer composition is selected from the group consisting of 2-ethylhexyl acrylate, butyl acrylate, ethyl acrylate, methyl acrylate, methyl methacrylate, 2-hydroxyethyl Acrylate, 2-hydroxypropyl acrylate, ureido methacrylate, glycidyl methacrylate, acetoacetoxyethyl methacrylate, hydroxypropyl carbamate acrylate, SIPOMER (trade name) CEA, styrene, vinyl acetate, Veova (R) 9, Veova (R) 10, Veova (R) EH, PAM-100, Lateral PD-420, Lateral (trade name), POMOL VS (trade name), Sippomer (trade name) COPS-I, PD-450, N-methylol acrylamide and diacetone acrylamide (combined with adipic acid dihydrazide through addition of adipic acid dihydrazide to the resulting dispersion)

Wherein the carboxylic acid group-containing ethylenically unsaturated monomer of the first step monomer composition is selected from acrylic acid, methacrylic acid, itaconic acid, and combinations thereof,

The ethylenically unsaturated monomer of the second-step monomer composition is selected from the group consisting of 2-ethylhexyl acrylate, butyl acrylate, ethyl acrylate, methyl acrylate, methyl methacrylate, styrene, vinyl acetate, Hydroxypropyl acrylate, 2-hydroxypropyl acrylate, cypro (trade name) COPS-I, Lateral PD-450, Golpanol (trade name) VS, ureido methacrylate, glycidyl methacrylate , Diacetone acrylamide (bonded to adipic acid dihydrazide through addition of adipic acid dihydrazide to the resulting dispersion), and ethylenically unsaturated carboxylic acid group-containing monomers such as acrylic acid, methacrylic Acid and itaconic acid, and combinations thereof,

The multi-ethylenically unsaturated monomer may be copolymerized with at least one monomer selected from the group consisting of divinylbenzene, allyl methacrylate, diethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, LaRomer (trade name) BDDA, and combinations thereof ≪ / RTI >

Way.

5. The method of any one of embodiments 1-4 wherein the ethylenically unsaturated monomer of the first stage monomer composition is selected from the group consisting of Veova TM 10, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate , Cypermer (trade name) COPS-I, Lateral PD-450, Golpanol (trade name) VS, ureido methacrylate, glycidyl methacrylate, diacetone acrylamide Ethylhexyl acrylate, butyl acrylate, ethyl acrylate, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl acrylate, butyl acrylate, Methacrylic acid, methacrylic acid, methacrylic acid, methacrylic acid, methacrylic acid, acrylate, acrylate, acrylate, and vinyl acetate.

6. The method of any one of embodiments 1-5 wherein the base is an aqueous inorganic base and is preferably selected from the group consisting of sodium hydroxide, potassium hydroxide and aqueous ammonia.

7. The method according to any one of embodiments 1 to 6, wherein the chain transfer agent is tertiary dodecyl mercaptan and / or 2-ethylhexyl thioglycolate.

8. A pressure-sensitive adhesive dispersion obtained by the method according to any one of the above-mentioned embodiments 1 to 7.

9. A process for producing a pressure sensitive adhesive comprising the steps of: adding a crosslinking agent to a pressure-sensitive adhesive dispersion obtained from any one of the above-mentioned methods 1 to 7; and optionally adding additional additives such as a wetting agent and a thickening agent. A method for manufacturing a pressure-sensitive adhesive formulation.

10. The method of embodiment 9 wherein when the pressure-sensitive adhesive dispersion has a pH value of less than 7.0, the method further comprises, prior to the step of adding the crosslinking agent to the pressure-sensitive adhesive dispersion, To a pH value of greater than 7.0, preferably less than 10. < Desc / Clms Page number 13 >

11. The method of embodiment 10 wherein the base is an aqueous inorganic base and is preferably selected from the group consisting of sodium hydroxide, potassium hydroxide and aqueous ammonia.

12. The composition of any one of embodiments 9-11, wherein the crosslinking agent is selected from the group consisting of polyfunctional aziridines, isocyanates, oxazolines, carbodiimides or combinations thereof such as NEOCRYL (trade name) CX Wherein the polymer is selected from the group consisting of X100 (trade name), Basonat (trade name) DS 3582, Basonot (trade name) LR 9056 or HYCASYL (trade name)

 13. The composition of any one of embodiments 9-12, wherein the amount of cross-linking agent is 0 to 10% by weight, preferably 0 to 8% by weight, more preferably 0.5 To 5% by weight, for example from 1 to 3% by weight.

14. A pressure-sensitive adhesive formulation obtained from any one of the methods of any of the embodiments 9-13.

15. A substrate coated with the pressure-sensitive adhesive dispersion of embodiment 8 or the pressure-sensitive adhesive formulation of embodiment 14 (preferably the substrate is selected from the group consisting of tapes, sheets, films, plates, etc., Is a protective film).

16. Use for producing a protective film of the pressure-sensitive adhesive dispersion of embodiment 8 above.

17. Use of the pressure-sensitive adhesive formulation of Embodiment 14 above for the manufacture of a protective film.

Example

The invention will be further described hereinafter with reference to specific embodiments, which are illustrative and explanatory only and not restrictive.

Each part and percent used is provided on a weight basis unless otherwise specified.

The materials used in the examples

Example 1. Preparation and application of dispersion P01

Polystyrene seed dispersion (4 g, solid content 33%) was introduced into the polymerization vessel. The polystyrene seed dispersion was heated and sodium persulfate (SPS, 7%, 71 g) was added when the temperature reached 80 占 폚. Thereafter, the addition of mixture 1 (consisting of 126 g of butyl acrylate, 22 g of acrylic acid and 1.3 g of tertiary dodecyl mercaptan) was started. 30 minutes after the start of the addition of the mixture 1, ammonia water (25%, 10.5 g) was added within 45 minutes. Upon completion of the above process, the addition of mixture 2 (consisting of 716 g of butyl acrylate, 42 g of styrene, 84 kg of methyl methacrylate and 7.7 g of LaRomber ™ BDDA) was started and continued for 3 hours, Sulfate (7%, 71 g) and aqueous ammonia (25%, 21 g) were added.

After the polymerization process, chemical deodorization was initiated. Sodium persulfate (7%, 22 g) and sodium bisulfite (1.5%, 50 g) were added to the polymerization vessel. The chemical turbidity was continued for 15 minutes, followed by cooling and filtration to obtain dispersion P01 (solid content 49.2 wt%, particle size about 245 nm and pH 8.3).

The dispersion P01 was blended with an aqueous solution (50 wt%, wetting agent) of 0.5% luminant (trade name) I-SC to form a blend F01a. Formulation F01a was further mixed with 2% by weight and 3% by weight of Varanate (trade name) LR 9056 (crosslinking agent) for 30 minutes with vigorous stirring to form Formulations F01b and F01c, respectively. Each of the formulations was cast on a corona-treated polyethylene film and dried at 70 DEG C for 3 minutes to form a protective film 01a, a protective film 01b, and a protective film 01c, respectively. The dry weight of the resulting adhesive layer was about 5 g / m ² .

Example 2. Preparation and application of dispersion P02

Dispersion P02 was prepared following the same procedure as in Example 1, except that the polystyrene seed dispersion was not included as an initial load in the polymerization vessel during the emulsion polymerization step.

The resulting dispersion P02 had a solids content of 44.6 wt%, a pH of 5.8, and a particle size of about 212 nm.

The dispersion P02 was neutralized to pH 7.4 with NaOH solution (8 wt%) and then combined with an aqueous solution (50 wt%) of 0.5% Lumiten (trade name) I-SC to form a combination F02a. Formulation F02a was further mixed with 2% by weight of Vasonat (trade name) LR 9056 for 30 minutes with vigorous agitation to form Formulation F02b. Each of the formulations F02a and F02b was cast on a corona-treated polyethylene film and dried at 70 DEG C for 3 minutes to form a protective film 02a and a protective film 02b. The dry weight of the resulting adhesive layer was about 5 g / m ² .

Example 3. Preparation and application of dispersion P03

Except that the introduced polystyrene seed dispersion was 3.3 g and the mixture 1 was composed of 11 g of 2-ethylhexyl acrylate, 82 g of butyl acrylate, 16 g of acrylic acid and 0.9 g of tertiary dodecyl mercaptan. To prepare a dispersion P03.

The obtained dispersion P03 had a solid content of 44.9 wt%, a pH of 6.7 and a particle size of about 203 nm.

The dispersion P03 was neutralized to pH 7.5 with NaOH solution (8 wt%) and then combined with an aqueous solution (50 wt%) of 0.5% Lumiten (trade name) I-SC to form a combination F03. Formulation F03 was cast on a corona treated polyethylene film and dried at 70 DEG C for 3 minutes to form protective film 03. [ The dry weight of the resulting adhesive layer was about 5 g / m ² .

Example 4. Preparation and application of dispersion P04

The dispersion P04 was prepared according to the same procedure as in Example 1 except that the reaction temperature was 90 占 폚.

The obtained dispersion P04 had a solids content of 41.9% by weight, a pH of 6.2 and a particle size of about 217 nm.

The dispersion P04 was neutralized to pH 7.8 with NaOH solution (8 wt%) and then combined with an aqueous solution (50 wt%) of 0.5% Lumiten (trade name) I-SC to form compound F04, Cast on a treated polyethylene film, and dried at 70 캜 for 3 minutes to form a protective film 04. The dry weight of the resulting adhesive layer was about 5 g / m ² .

Example 5. Preparation and application of dispersion P05

3.1 g of the introduced polystyrene seed dispersion, and the mixture 1 consisted of 69 g of butyl acrylate, 19 g of acrylic acid, 9.9 g of diacetone acrylamide and 0.9 g of tertiary dodecyl mercaptan, followed by cooling and filtration Dispersion P05 was prepared according to the same procedure as in Example 1, except that 10.2 g of adipic acid hydrazide was added to the dispersion.

The resulting dispersion P05 had a solids content of 44% by weight, a particle size of about 189 nm and a pH of 6.5.

The dispersion P05 was neutralized to pH 8.0 with a NaOH solution (8 wt%) and then combined with an aqueous solution (50 wt%) of 0.5% Luminen (trade name) I-SC to form a combination F05a. Formulation F05a was further mixed with 2% by weight of Barenot (trade name) LR 9056 for 30 minutes with vigorous agitation to form formulation F05b. Each of the formulations F05a and F05b was cast on a corona-treated polyethylene film and dried at 70 DEG C for 3 minutes to form a protective film 05a and a protective film 05b. The dry weight of the resulting adhesive layer was about 5 g / m ² .

Example 6. Preparation and application of dispersion P06

The initial load of the polystyrene seed dispersion was 3.3 g, and the mixture 1 consisted of 90 g of butyl acrylate, 18.5 g of acrylic acid and 0.9 g of 2-ethylhexyl thioglycolate, and 820 g of mixture 2 of butyl acrylate, 48 g of styrene Dispersion P06 was prepared according to the same procedure as in Example 1, except that it consisted of 95 kg of methyl methacrylate, 8.5 g of LaRomer (trade name) BDDA, and 11.5 g of Sapormer COPS-1 (40% by weight in water) .

The resulting dispersion P06 had a solids content of 45.7 wt%, a particle size of about 195 nm and a pH of 6.8.

The dispersion P06 was neutralized to pH 8.0 with a NaOH solution (8 wt%) and then combined with an aqueous solution (50 wt%) of 0.5% Luminen (trade name) I-SC to form a combination F06a. Formulation F06a was further blended with 1 wt.% Of BARSONAT ™ LR 9056, 2 wt.% Of BARONAT ™ LR 9056, 3 wt.% Of BARONAT ™ LR 9056, 5 wt. (Product name) LR 9056 and 10% by weight of Vasonat (trade name) LR 9056 for 30 minutes with vigorous stirring to form Formulation F06b, Formulation F06c, Formulation F06d, Formulation F06e, and Formulation F06f. The above formulations F06a, Formulation F06b, Formulation F06c, Formulation F06d, Formulation F06e and Formulation F06f were each cast on a corona-treated polyethylene film and dried at 70 ° C for 3 minutes to form a protective film 06a, a protective film 06b, A protective film 06d, a protective film 06e, and a protective film 06f were formed. The dry weight of the resulting adhesive layer was about 5 g / m ² .

Example 7. Preparation and application of dispersion P07

3.3 g of the introduced polystyrene seed dispersion, and the mixture 1 was composed of 93 g of butyl acrylate, 6.5 g of acrylic acid, 0.9 g of 2-ethylhexyl thioglycolate and 11 g of Lateral PD450, and the mixture 2 was butyl acrylate 830 g, 50 g of styrene, 98 kg of methyl methacrylate, and 9 g of LaRomar (trade name) BDDA, to prepare a dispersion P07.

The obtained dispersion P07 had a solid content of 45.2 wt%, a particle size of about 270 nm and a pH of 6.3.

The dispersion P07 was neutralized to pH 7.5 with a NaOH solution (8 wt%) and then mixed with an aqueous solution (50 wt%) of 0.5% LOUMITEN (trade name) I-SC and further added with 2 wt% LR 9056 with mixing for 30 minutes with vigorous agitation to form a blend F07, after which the blend F07 was cast on a corona-treated polyethylene film and dried at 70 DEG C for 3 minutes to form a protective film 07. The dry weight of the resulting adhesive layer was about 5 g / m ² .

Example 8. Preparation and application of dispersion P08

3.3 g of the introduced polystyrene seed dispersion, and the mixture 1 was composed of 93 g of butyl acrylate, 16 g of methacrylic acid, 0.9 g of tertiary dodecyl mercaptan and 11 g of Lateral PD450, and the mixture 2 was butyl acrylate Except that ammonia water (25%, 8.6 g) was used for the addition of ammonia water two times, and that the aqueous ammonia solution (883 g), methyl methacrylate (98 kg) To prepare a dispersion P08.

The resulting dispersion P08 had a solids content of 44.6 wt%, a particle size of about 272 nm and a pH of 9.1.

The dispersion P08 was mixed with a 0.5% aqueous solution of I-SC (trade name) I-SC (trade name) and further mixed with 2 wt% of BARONAT (trade name) LR 9056 for 30 minutes while vigorously stirring to form a compound F08 , And then the combination F08 was cast on a corona-treated polyethylene film and dried at 70 DEG C for 3 minutes to form a protective film 08. The dry weight of the resulting adhesive layer was about 5 g / m ² .

Example 9: Adhesive performance test and protective film application result

The protective film 01a obtained from Example 1 was applied on a steel panel to form a coated steel panel. The coated steel panels were then aged for 7 days at 70 DEG C and 85% relative humidity. Thereafter, the protective film 01a was peeled from the steel panel. Then, the appearance of the obtained gangue steel panel was observed, and the results were reported in the following table.

The above procedure was repeated using the protective films 01b, 01c, 02a, 02b, 03, 04, 05a, 05b, 06a, 06b, 06c, 06d, 06e, 06f, 07, Test series 1 corresponds to protective films 01a, 01b, 01c, test series 2 corresponds to protective films 02a, 02b, test series 3 corresponds to protective film 03, test series 4 corresponds to protective film 04, Test series 5 corresponds to protective film 05a, 05b, test series 6 corresponds to protective film 06a, 06b, 06c, 06d, 06e, 06f, test series 7 corresponds to protective film 07, It corresponds to film 08.

In order to evaluate the adhesive performance of the protective film, the appearance of each test was rated by a rating system as follows.

Grade 1: There is no clear, residue-free and visible shadow when viewed perpendicular to the surface of the steel panel under normal indoor daylight, but very weak when observed in a direction with a certain angle to the direction perpendicular to the observed surface Shadow is observed.

Grade 2: There is no clear, residue-free and visible shadow when observing the surface of the steel panel under normal indoor daylight, but very weak shadows are observed when observed under near light illumination.

Grade 3: There is no clear, residue-free and visible shadow when viewed under normal room daylight, but very weak shadows are observed when viewed under a light source close to a direction at a predetermined angle to the direction normal to the observed surface .

Grade 4: Clear, residue free, no visible shadows when viewed under close light irradiation at all possible viewing angles.

The results are provided in Table 1 below.

Test series number Dispersion liquid * Crosslinking agent BARONAT (trade name) LR 9056 Formulation ** Protective film Grade of exterior appearance of man steel panel One P01 0 wt% F01a 01a Grade 2 P01 2 wt% F01b 01b Grade 3 P01 3 wt% F01c 01c Grade 3 2 P02 0 wt% F02a 02a Class 1 P02 2 wt% F02b 02b Grade 3 3 P03 0 wt% F03 03 Class 1 4 P04 0 wt% F04 04 Class 1 5 P05 0 wt% F05a 05a Grade 3 P05 2 wt% F05b 05b Grade 4 6 P06 0 wt% F06a 06a Grade 2 P06 1 wt% F06b 06b Grade 3 P06 2 wt% F06c 06c Grade 4 P06 3 wt% F06d 06d Grade 4 P06 5 wt% F06e 06e Grade 4 P06 10 wt% F06f 06f Grade 4 7 P07 2 wt% F07 07 Grade 3 8 P08 2 wt% F08 08 Grade 3

* Combined with 0.5% Lumiten (trade name) I-SC as a humectant and having a pH of greater than 7.3.

** Percentage of crosslinking agent provided based on the total weight of the formulation.

As can be seen from the data in Table 1, all of the protective films obtained from the present invention provide a clean, residue-free, and shadowless appearance of the surface when viewed perpendicular to the steel panel surface under normal illumination .

As can be seen from series 1, 2, 5 and 6, the addition of cross-linking agent will make the appearance of the surface better.

Example 5 for making Protective Film 05 used a monomer combination of DAAM / ADH, the results of which are generally superior to those of Test Series 2.

Example 6 for the preparation of protective film 06 additionally used functional monomers and the results of this series of tests 6 are generally superior to those of series 2 of the tests.

The invention is not to be limited in scope by the specific embodiments and examples described herein. Indeed, various modifications of the invention in addition to those described herein will become apparent to those skilled in the art from the following description and accompanying drawings. Such changes are within the scope of the appended claims.

It is also to be understood that all values are approximations and are provided for explanation.

Claims (17)

1) A process for producing a first-stage dispersion comprising: (i) obtaining a first-stage polymer particle from a first-stage monomer composition consisting of an ethylenically unsaturated monomer and at least one ethylenically unsaturated monomer containing a carboxylic acid group in an aqueous medium to form a first- Wherein the carboxylic acid group-containing ethylenically unsaturated monomer is contained in an amount of at least 1.0 wt% (preferably 10 to 30 wt%) of the first stage monomer composition;
(ii) adding a chain transfer agent to the first-step monomer composition, wherein the addition amount of the chain transfer agent is 0.3 to 1.5% by weight, preferably 0.3 to 1.1% by weight; And
(iii) neutralizing the first-stage dispersion with an aqueous base solution to a pH value of 5.0 to 7.0, preferably 6.0 to 7.0
A first emulsion polymerization step comprising:
2) in the presence of a neutralized first stage dispersion, a second stage monomer composition consisting of an ethylenically unsaturated monomer and optionally one or more multi-ethylenically unsaturated monomers is polymerized into said first stage polymer particles to form second stage polymer particles , Thereby obtaining a pressure-sensitive adhesive dispersion, a second emulsion polymerization step
Wherein the weight ratio of the first stage monomer composition to the total amount of the first stage monomer composition and the second stage monomer composition is 5 to 50 wt%, preferably 8 to 30 wt%, e.g., 10 To 20% by weight,
Sensitive adhesive agent dispersion. The method according to claim 1,
A water-soluble initiator is used in the emulsion polymerization, and preferably the water-soluble initiator is a thermal initiator and a redox initiator such as sodium persulfate, potassium persulfate, ammonium persulfate, sodium acetone bisulfite / Tert-butyl hydroperoxide, and sodium bisulfite / sodium persulfate. 3. The method according to claim 1 or 2,
Wherein said multi-ethylenically unsaturated monomer is used in an amount of from 0.3 to 2.0% by weight, preferably from 0.5 to 1.6% by weight of said second-stage monomer composition. 4. The method according to any one of claims 1 to 3,
Wherein the ethylenically unsaturated monomer of the first stage monomer composition is selected from the group consisting of (meth) acrylates with and without functional groups, vinyl and allyl monomers with / without functional groups, other functional ethylenically unsaturated monomers and combinations thereof Wherein the ethylenically unsaturated monomer of the first step monomer composition is selected from the group consisting of 2-ethylhexyl acrylate, butyl acrylate, ethyl acrylate, methyl acrylate, methyl methacrylate, 2-hydroxyethyl Acrylate, 2-hydroxypropyl acrylate, ureido methacrylate, glycidyl methacrylate, acetoacetoxyethyl methacrylate, hydroxypropyl carbamate acrylate, SIPOMER (trade name) CEA, styrene, vinyl acetate, VeoVa (registered trademark) 9, Veova (registered trademark) 10, Veova (registered trademark) E 100, SEMOPER (trade name) PAM-100, LATEMUL (trade name), and SEMO (trade name) PD-420, Rothermal PD-450, N-methylol acrylamide and diacetone acrylamide, which is coupled with adipic acid dihydrazide through the addition of adipic acid dihydrazide to the obtained dispersion ), ≪ / RTI >
Wherein the carboxylic acid group-containing ethylenically unsaturated monomer of the first step monomer composition is selected from acrylic acid, methacrylic acid, itaconic acid, and combinations thereof,
Wherein the ethylenically unsaturated monomer of the second stage monomer composition is selected from the group consisting of 2-ethylhexyl acrylate, butyl acrylate, ethyl acrylate, methyl acrylate, methyl methacrylate, styrene, vinyl acetate, Hydroxypropyl acrylate, 2-hydroxypropyl acrylate, cypro (trade name) COPS-I, Lateral PD-450, Golpanol (trade name) VS, ureido methacrylate, glycidyl methacrylate , And diacetone acrylamide (which is coupled with adipic acid dihydrazide through addition of adipic acid dihydrazide to the resulting dispersion), and combinations thereof,
Wherein said multi-ethylenically unsaturated monomer is selected from the group consisting of divinylbenzene, allyl methacrylate, diethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, LaRomer (trade name) BDDA, and combinations thereof ≪ / RTI >
Way. 5. The method according to any one of claims 1 to 4,
Wherein the ethylenically unsaturated monomer of the first stage monomer composition is selected from the group consisting of VEOVA 10, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, SEPHORM (trade name) COPS-I, LATEMUL ) PD-450, Golpanol (trade name) VS, ureido methacrylate, glycidyl methacrylate, and diacetone acrylamide, which is obtained by adding adipic acid dihydrazide to the obtained dispersion Ethylhexyl acrylate, butyl acrylate, ethyl acrylate, methyl acrylate, methyl methacrylate, styrene and vinyl acetate) in combination with an ethylenically unsaturated monomer selected from the group consisting of Lt; RTI ID = 0.0 > ethylenically unsaturated < / RTI > 6. The method according to any one of claims 1 to 5,
Wherein the base is an aqueous inorganic base and is preferably selected from the group consisting of sodium hydroxide, potassium hydroxide and aqueous ammonia. 7. The method according to any one of claims 1 to 6,
Wherein the chain transfer agent is tertiary dodecyl mercaptan and / or 2-ethylhexyl thioglycolate. A pressure-sensitive adhesive dispersion obtained from the process of any one of claims 1 to 7. Adding a crosslinking agent to the pressure-sensitive adhesive dispersion obtained from the process of any one of claims 1 to 7, and
Optionally, adding additional additives, such as a wetting agent and a thickener,
≪ / RTI > wherein the pressure-sensitive adhesive formulation comprises at least one of the following. 10. The method of claim 9,
When the pressure-sensitive adhesive dispersion has a pH value of less than 7.0, the method further comprises, prior to the step of adding the crosslinking agent to the pressure-sensitive adhesive dispersion, the pressure-sensitive adhesive dispersion has a pH value of greater than 7.0, ≪ / RTI > with a base. 11. The method of claim 10,
Wherein the base is an aqueous inorganic base and is preferably selected from the group consisting of sodium hydroxide, potassium hydroxide and aqueous ammonia. 12. The method according to any one of claims 9 to 11,
The cross-linking agent may be a polyfunctional aziridine, isocyanate, oxazoline, carbodiimide or combinations thereof such as NEOCRYL (trade name) CX-100, XAMA (trade name) 7, Basonat (Trade name) DS 3582, BASONAT (trade name) LR 9056, or HYCASYL (trade mark) 510. 13. The method according to any one of claims 9 to 12,
The amount of crosslinking agent is in the range of 0 to 10% by weight, preferably 0 to 8% by weight, more preferably 0.5 to 5% by weight, for example 1 to 3% by weight, based on the total weight of the pressure- In method. A pressure-sensitive adhesive formulation obtained from the process of any one of claims 9 to 13. The substrate coated with the pressure-sensitive adhesive dispersion of claim 8 or the pressure-sensitive adhesive formulation of claim 14, wherein the substrate is preferably selected from the group consisting of tape, sheet, film, plate, etc. More preferably, Film, coated substrate. Use of the pressure-sensitive adhesive dispersion of claim 8 for the manufacture of a protective film. Use of the pressure-sensitive adhesive formulation of claim 14 for the manufacture of a protective film.