DE10212659A1 - Branched organosiloxane copolymers with terminal silicon-carbon groups useful as antimisting additives and for decreasing aerosol formation in crosslinkable silicone coating compositions - Google Patents

Abstract

Branched organosiloxane copolymers with terminal silicon-carbon groups are new. Branched organosiloxane copolymers of formula (I) with terminal silicon-carbon groups are new. Y(-CnH2n-(R2SiO)m-Ap-R2Si-G)x (I) -R2Si-R2-(R2SiO)m (II) Y = one to three valent 1-25C hydrocarbon group, containing one or more hetero atoms selected from nitrogen, oxygen and silicon; R = monovalent, optionally halogenated 1-18C hydrocarbon group; A = a residue of formula (II); R2 = divalent 2-30C hydrocarbon group, which can be interrupted by one or more oxygen atoms; G = a monovalent residue of formula CfH2f-2k-Z or a divalent residue of formula -CnH2n-, where the two bonds are bonds to a further Y group; Z = a monovalent terminal aliphatic hydrocarbon residue free from C-C multiple bonds, which is inert to SiH groups in hydrosilylation reactions, and which optionally comprises one or more hetero atoms selected from oxygen, nitrogen, boron, silicon, and titanium, or a monovalent polymer residue with more than 20 C atoms; x = 3-10; f, n = 2-12; k = 0 or 1; m = at least 1; and p = 0 or a positive number. with the proviso that the branched organosiloxane polymer contains on average at least one Z group. Independent claims are included for: (1) Preparation of the organosiloxane polymers (I) in a two step process; (2) A crosslinkable silicone coating composition with decreased aerosol formation comprising (X) an antimisting additive in accordance with the above, (A) organosilicon compounds comprising C-C unsaturation, (B) organosilicon compounds with silicon-bonded hydrogen atoms, (C) catalysts for the addition of silicon-bonded hydrogen to C-C unsaturation, and optionally (D) inhibitors; (3) A shaped body obtained by cross-linking the above coating composition; (4) A process for production of coatings by application of the crosslinkable composition to a surface, followed by crosslinking; and (5) A process for preparation of a coating of an adhesive material by application of the crosslinkable composition to the adhesive coating surface followed by crosslinking.

Description

The invention relates to the use of antimisting additives to reduce aerosol formation in crosslinkable Silicone coating compositions.

A trend in the silicone coating industry is the increase the machine speed to increase productivity. Apply silicone coatings to the substrate at higher Speeds, for example of over 300 m / min. applied, fine spray of the Form silicone coating system. This aerosol is created at the silicone applicator. This spray formation proves to be a serious problem with the further increase of the coating speed.

This spray formation can be achieved by adding so-called Antimisting additives to the silicone coating system reduced become.

Antimisting is disclosed in EP-A 716 115 (Dow Corning Corp.) Additives obtained by reacting an organosilicon compound, an oxyalkylene group-containing compound and one Be obtained catalyst described. By the encore of these reaction products containing oxyalkylene groups crosslinkable silicone coating systems will form Aerosol reduced in fast coating processes.

• a) eines Organohydrogenpolysiloxans mit mindestens 2 Si-H- Gruppen (SiH) mit
• b) eines Organoalkenylsiloxans mit mindestens 3 Alkenylgruppen (C=C) in
• c) Gegenwart eines Platinkatalysators und gegebenenfalls
• d) eines Inhibitors

in einem Verhältnis von C=C/SiH ≥ 4,6 erhalten wird. WO 01/98420 (Dow Corning Corp.) discloses a liquid silicone antimisting composition, which by reaction

• a) an organohydrogenpolysiloxane with at least 2 Si-H groups (SiH) with
• b) an organoalkenylsiloxane with at least 3 alkenyl groups (C = C) in
• c) presence of a platinum catalyst and optionally
• d) an inhibitor

is obtained in a ratio of C = C / SiH ≥ 4.6.

An extremely large excess of organoalkenylsiloxane (C = C) is necessary so that there is no retaliation. This Excess affects the release properties of the base Systems, the crosslinkable silicone coating composition. An inhibitor must also be used to prevent gelling be added.

The task was antimisting additives for To provide silicone coating compositions that Reduce aerosol formation in fast coating processes, which is well miscible with the silicone coating compositions are and the silicone coating compositions are not affect. The object is achieved by the invention.

The invention relates to the use of antimisting additives in crosslinkable silicone coating compositions for reducing aerosol formation, characterized in that branched organosiloxane (co) polymers containing structural elements of the formula are used as antimisting additives

Y [-C _n H _2n - (R ₂ SiO) _m -A _p -R ₂ Si-G] _x (I)

in which
Y is a tri- to tetravalent, preferably tri- to tetravalent, hydrocarbon radical which can contain one or more heteroatoms selected from the group of oxygen, nitrogen and silicon atoms,
R can be the same or different and represents a monovalent optionally halogenated hydrocarbon radical having 1 to 18 carbon atoms per radical,
A is a radical of the formula -R ₂ Si-R ² - (R ₂ SiO) _m -, where R ^{2 is} a divalent hydrocarbon radical having 2 to 30 carbon atoms, which is separated by one or more oxygen atoms, preferably 1 to 4 oxygen atoms can be interrupted means
G denotes a monovalent radical of the formula -C _f H _2f-2k -Z or a divalent radical of the formula -C _n H _2n -, where the second bond is to a further radical Y,
Z is a monovalent hydrocarbon radical free from terminal aliphatic carbon-carbon multiple bonds, which is inert towards SiH groups in hydrosilylation reactions and can contain one or more heteroatoms selected from the group consisting of oxygen, nitrogen, boron, silicon and titanium, or with a monovalent polymer radical means more than 20 carbon atoms,
x is an integer from 3 to 10,
is preferably 3 or 4,
f is an integer from 2 to 12, preferably 2,
k is 0 or 1
n is an integer from 2 to 12, preferably 2,
m is an integer of at least 1,
is preferably an integer from 1 to 1000 and
p 0 or an integer positive number,
is preferably 0 or an integer from 1 to 20,
with the proviso that the branched organosiloxane (co) polymers contain an average of at least one group Z.

The invention furthermore relates to the use of antimisting additives in crosslinkable silicone coating compositions for reducing the formation of aerosols, characterized in that
As antimisting additives, branched organosiloxane (co) polymers can be produced by in a first step
at least three compounds (1) of the formula which have aliphatic double bonds

Y (CR ¹ = CH ₂ ) _x

where Y and x have the meaning given above and R ^{1 represents} a hydrogen atom or an alkyl radical having 1 to 10 carbon atoms
with organopolysiloxanes (2) of the general formula

H (R ₂ SiO) _m A _p -R ₂ SiH

where A, R, m and p have the meaning given above, in the presence of catalysts (3) which promote the addition of Si-bonded hydrogen to aliphatic multiple bonds, so-called hydrosilylation catalyst,
be implemented
and in a second step the branched intermediates (5) thus obtained containing Si-bonded hydrogen atoms with organic compounds (4) of the formula

C _f H _2f-2k-1 -Z

selected from the group of
if k = 0:

H ₂ C = CR ³ -Z (4a) and

if k = 1:

R ₄ C ~ CZ (4b)

wherein R ³ and R ^{4 have} the meaning of R ¹ , and
f, k and Z have the meaning given above,
in the presence of catalysts (3) which promote the attachment of Si-bonded hydrogen to aliphatic multiple bonds,
be used.

The antimisting additives according to the invention, the branched Organosiloxane (co) polymers have the advantage that they do not only aerosol formation can be networked Reduce silicone coating compositions in rapid coating systems but that they are used in particular at least in the Quantity ratios homogeneous with the cross-linkable Silicone coating compositions are miscible in Contrary to the antimisting containing polyglycol groups Additives according to EP-A 716 115 cited at the beginning.

The antimisting additives according to the invention also have additives no inhibitory effect and they are stable on storage. The Antimisting additives according to the invention have the advantage that them beforehand with the polymer component (A) of the crosslinkable Silicone coating composition can be mixed. They are easy to handle and affect the Release properties of the basic system, the networkable Silicone coating composition, not.

The organosiloxane (co) polymers with a branched structure basically contain chain-like siloxane blocks, the ends of which are each connected to the structural elements Y and Z via a C _f H _2f or C _f H _2f-2 bridge. The more siloxane blocks are connected to elements Y on both sides, the more branched are the products produced. In general, the organosiloxane (co) polymers according to the invention are constructed in such a way that siloxane blocks and organic blocks alternate with one another, the branching structures and the ends consisting of organic blocks.

In the organosiloxane (co) polymers according to the invention, this is Ratio of end groups Z to branch groups Y (Z / Y ratio) preferably 1.0 to 2.0, preferably 1.1 to 1.5.

The organosiloxane (co) polymers according to the invention have preferably a viscosity of 50 to 50,000,000 mPa.s 25 ° C, preferably 400 to 5,000,000 mPa.s at 25 ° C and particularly preferably 400 to 1,000,000 mPa.s at 25 ° C.

Examples of radicals R are alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl, neo-pentyl, tert-pentyl, Hexyl radicals, such as the n-hexyl radical, heptyl radicals, such as the n-heptyl radical, Octyl radicals, such as the n-octyl radical and iso-octyl radicals, such as the 2,2,4-trimethylpentyl radical, nonyl radicals, such as the n-nonyl radical, Decyl residues, such as the n-decyl residue, dodecyl residues, such as the n-dodecyl and octadecyl such as the n-octadecyl; Cycloalkyl radicals, such as cyclopentyl, cyclohexyl, cycloheptyl and methylcyclohexyl; Aryl radicals, such as the phenyl, naphthyl, Anthryl and phenanthryl; Alkaryl residues, such as o-, m-, p- Tolyl, xylyl and ethylphenyl; and aralkyl residues, such as the benzyl radical, the α- and the β-phenylethyl radical.

Examples of halogenated radicals R are haloalkyl radicals, such as the 3,3,3-trifluoro-n-propyl radical, the 2,2,2,2 ', 2', 2'-Hexafluorisopropylrest, the Heptafluorisopropylrest and Halogenaryl radicals, such as the o-, m- and p-chlorophenyl radicals.

The radical R is preferably a monovalent one Hydrocarbon radical with 1 to 6 carbon atoms, the Methyl radical is particularly preferred.

Examples of alkyl radicals R ¹ are the methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl, neo -Pentyl, tert-pentyl, hexyl, such as the n-hexyl, heptyl, such as the n-heptyl, octyl, such as the n-octyl and iso-octyl, such as the 2,2,4-trimethylpentyl, nonyl, such as the n-nonyl radical and decyl radicals, such as the n-decyl radical. R ¹ is preferably a hydrogen atom.

Examples of radicals R ² are those of the formula

- (CH ₂ ) ₂ -

- (CH ₂ ) ₄ -

- (CH ₂ ) ₆ -

- (CH ₂ ) ₈ -

- (CH ₂ ) ₁₀ -

-C ₆ H ₄ -

-C ₂ H ₄ C ₆ H ₄ C ₂ H ₄ -

-C (CH ₃ ) CH ₂ C ₆ H ₄ CH ₂ O (CH ₃ ) - and

-C ₂ H ₄ -norbornanediyl-.

Examples of radicals R ¹ apply in full to radicals R ³ and R ⁴ .

R ³ is preferably a hydrogen atom.

R ⁴ is preferably a hydrogen atom.

In the first process step, the addition of the SiH group from (2) to the CH ₂ = CR ¹ group of (I), the so-called hydrosilylation, leads to the formation of two isomers known to the person skilled in the art as follows:

The -C _n H _2n group in (I) of the organosiloxane (co) polymers according to the invention comprises this isomer formation and therefore preferably means the isomeric radicals


and therefore n is the total number of carbon atoms in the CH ₂ = CR ¹ group of (I). Since R ^{1 is} preferably a hydrogen atom, n is preferably 2.

In the method according to the invention, a type of Connection (1) or different types of connection (1) be used.

Examples of compounds (1) with which the branched organosiloxane (co) polymers according to the invention can be prepared are
1,2,4-trivinylcyclohexane,
1,3,5-Trivinylcyclohexane,
3,5-dimethyl-4-vinyl-1,6-heptadiene,
1,2,3,4-tetra vinylcyclobutane,
methyltrivinylsilane,
tetravinylsilane,
1,1,2,2-tetraallyloxyethane,
with 1,2,4-trivinylcyclohexane being preferred.

Examples of the radical Y are therefore those of the formula




being the rest of the formula


is preferred.

In the method according to the invention, a type of Organopolysiloxane (2) or different types of Organopolysioxane (2) can be used.

A largely linear polymer is used as the organopolysiloxane (2).
p is preferably 0.
m is preferably an integer from 5 to 400.

Organopolysiloxane (2) is in the first process step in such quantities that the ratio of Si bound hydrogen in organopolysiloxane (2) aliphatic double bond in compound (1) preferably at least 1.5, preferably 1.5 to 20, particularly preferably 1.5 to 5.0, particularly preferably 1.5 to 3.0.

Since organopolysiloxane (2) is preferably used in excess everyone will react in the first process step aliphatic double bonds in compound (1), and it branched organosiloxane (co) polymers (5) are obtained which Have Si-bonded hydrogen atoms. In case of low molecular weight organopolysiloxanes (2) with p = 0 and m = 1-6 can by the subsequent distillative removal of the excess organopolysiloxane (2) intermediates (5) can be obtained practically free of organopolysiloxane (2). In in the other cases, excess organopolysiloxane (2) preferably left in the reaction mixture, whereby the Intermediates (5) are diluted. To soluble, d. H. Obtaining uncrosslinked intermediates (5) is therefore preferably a molar ratio of SiH in (2) to C = C in (1) of used at least 1.5. The required molar ratio depends on the structure of (1) and the index x and can be carried out by the specialist in individual cases through manual tests can be determined experimentally.

As catalysts (3) promoting the attachment of Si-bonded hydrogen to aliphatic multiple bonds, the same catalysts can also be used in the process according to the invention as have previously been used to promote the attachment of Si-bonded hydrogen to aliphatic multiple bonds. The catalysts are preferably a metal from the group of platinum metals or a compound or a complex from the group of platinum metals. Examples of such catalysts are metallic and finely divided platinum, which can be on supports such as silicon dioxide, aluminum oxide or activated carbon, compounds or complexes of platinum, such as platinum halides, e.g. B. PtCl ₄ , H ₂ PtCl ₆ .6H ₂ O, Na ₂ PtCl ₄ .4H ₂ O, platinum-olefin complexes, platinum-alcohol complexes, platinum-alcoholate complexes, platinum-ether complexes, platinum-aldehyde Complexes, platinum-ketone complexes, including reaction products of H ₂ PtCl ₆ .6H ₂ O and cyclohexanone, platinum-vinyl-siloxane complexes, such as platinum-1,3-divinyl-1,1,3,3-tetra- methyl-disiloxane complexes with or without detectable inorganic halogen, bis (gamma-picolin) platinum dichloride, trimethylene dipyridine platinum dichloride, dicyclopentadiene platinum dichloride, dimethyl sulfoxydethylene platinum (II) di-chloride, cyclooctadiene-platinum dichloride platinum dichloride , Cyclopentadiene-platinum dichloride, and reaction products of platinum tetrachloride with olefin and primary amine or secondary amine or primary and secondary amine, such as the reaction product of platinum tetrachloride dissolved in 1-octene with sec-butylamine or ammonium-platinum complexes.

The catalyst (3) is in the first process step preferably in amounts of 0.2 to 20 ppm by weight (parts by weight per million parts by weight), preferably in amounts of 1 to 10 ppm by weight, each calculated as elemental platinum and related on the total weight of compound (1) and organopolysiloxane (2) used.

The first process step is preferably when printing the surrounding atmosphere, i.e. at around 1020 hPa (abs.), performed, but it can also be done at higher or lower Pressures are carried out. Furthermore, the first Process step preferably at a temperature of 20 ° C. up to 150 ° C, preferably 40 ° C to 100 ° C.

Since the at least three aliphatic double bonds Compound (1), e.g. B. 1,2,4-trivinylcyclohexane, at higher Temperatures tending to polymerize can occur in the first Process step preferably radical inhibitors, such as 4- Methoxyphenol, 2,6-bis (tert.butyl) -4-methylphenol, Phenothiazine, hydroquinone or pyrocatechol also used become. The radical inhibitors are preferably in Amounts from 10 to 500 ppm by weight, based on the total weight on compound (1) and organopolysiloxane (2).

In the first as well as in the second process step preferably inert organic solvents are used become. Examples of inert organic solvents are Toluene, xylene, octane isomers, heptane isomers, butyl acetate, 1,2- Dimethoxyethane, tetrahydrofuran and cyclohexane.

The inert organic which may also be used Solvents can be used after the first or second Process step are removed by distillation or in Reaction mixture remain.

The organic compounds (4) contain aliphatic C-C- Double or triple bonds compared to Si-H groups in Hydrosilylation reactions are reactive and below Accumulate the formation of Si-C bonds.

If k = 0, the reactive group contains a double bond and the organic compound (4) is a compound (4a) of the formula H ₂ C = CR ³ -Z.

When k = 1, the reactive group contains a triple bond and the organic compound (4) is a compound (4b) of the formula of the formula R ⁴ C ~ CZ.

When the SiH group in the intermediate (5) is attached to the double or triple bond in (4a) or (4b), the formation of isomers known to the person skilled in the art occurs as follows:

The -C _f H _2f-2k group in (I) of the organosiloxane (co) polymers according to the invention comprises this isomer formation and therefore preferably means the isomeric radicals


and f is therefore the total number of carbon atoms in the H ₂ C = CR ³ group of (4a) or the R ⁴ O ~ C group of (4b).

Since R ³ and R ^{4 are} preferably hydrogen atoms, f is therefore preferably 2.

Examples of the H ₂ C = CR group in the organic compound (4a) are

H ₂ C = CH-

H ₂ C = C (CH ₃ ) -

H ₂ C = C (C ₄ H ₉ ) - and

H ₂ C = C (C ₈ H ₁₇ ) -.

Examples of the R ⁴ C ~ C group in the organic compound (4b) are

HC ~ C-

CH ₃ C ~ C and

C ₄ H ₉ C ~ C-.

The radical Z in bound to the double or triple bond (4a) or (4b) can contain carbon and hydrogen atoms also one or more heteroatoms selected from the group of Contain oxygen, nitrogen, boron, silicon and titanium and is in a hydrosilylation reaction against SiH groups not reactive.

The unsaturated compound (4) can thus have functional groups contain, such as hydroxy, ether, ester, amido, urethane, Urea, amino, oximo, imino, carboxyl, carbonyl or Epoxy groups. It preferably does not contain any groups that Significantly hinder the hydrosilylation reaction.

Examples of Z radicals are

- (CH ₂ ) ₅ CH ₃

- (CH ₂ ) ₉ CH ₃

- (CH ₂ ) ₁₅ CH ₃

-C (CH ₃ ) ₂ OH

- (CH ₂ ) ₄ OH

-OC ₂ H ₉

-CO ₂ CH ₃

- (CH ₂ ) ₈ CO ₂ C ₃ H ₇

- (CH ₂ ) ₈ CON (C ₂ H ₅ ) ₂

-CH ₂ O ₂ CNHC ₁₈ H ₃₇

-CH ₂ NHCONHC ₁₈ H ₃₇

-CH ₂ NH ₂

- (CH ₂ ) ₈ CO ₂ H

-COO ₂ H

-COCH ₃ and

Examples of radicals G are therefore

- (CH ₂ ) ₇ CH ₃

- (CH ₂ ) ₁₁ CH ₃

- (CH ₂ ) ₁₇ CH ₃

- (CH ₂ ) ₂ C (CH ₃ ) ₂ OH

-CH = CH-C (CH ₃ ) ₂ OH

- (CH ₂ ) ₆ OH

- (CH ₂ ) ₂ CO ₄ H ₉

- (CH ₂ ) ₂ CO ₂ CH ₃

- (CH ₂ ) ₁₀ CO ₂ O ₂ H ₇

- (CH ₂ ) ₁₀ CON (C ₂ H ₅ ) ₂

- (CH ₂ ) ₃ O ₂ CNHC ₁₈ H ₃₇

- (CH ₂ ) ₃ NHCONHC ₁₈ H ₃₇

- (CH ₂ ) ₃ NH ₂

- (CH ₂ ) ₁₀ CO ₂ H

- (CH ₂ ) ₂ CO ₂ H

- (CH ₂ ) ₂ COCH ₃ and

The unsaturated compound (4) can be monomeric, oligomeric or have a polymeric character. Therefore correspond to the definition of Z also organic residues, the polyether, polyester, polyurethane, Polyurea, polyamide, polyolefin, polyacrylate or Contain polyacetal. Are preferred as polymer residues Polyether, polyester, polyolefin and polyacrylate.

Examples of organic compounds (4a) are

CH ₂ = CH (CH ₂ ) ₅ CH ₃

CH ₂ = CH (CH ₂ ) ₁₅ OH ₃

CH ₂ = CH-C (CH ₃ ) ₂ OH

CH ₂ = CH (CH ₂ ) ₄ OH

CH ₂ = CHOC ₄ H ₉

CH ₂ = CHCO ₂ CH ₃

CH ₂ = CH (CH ₂ ) ₈ CO ₂ C ₃ H ₇

CH ₂ = CH (CH ₂ ) ₈ CON (C ₂ H ₅ ) ₂

CH ₂ = CH-CH ₂ O ₂ CNHC ₁₈ H ₃₇

CH ₂ = CH-CH ₂ NH ₂

CH ₂ = CH (CH ₂ ) ₈ CO ₂ H

CH ₂ = CH-COCH ₃ and

Examples of organic compounds (4b) are

CH ~ CC ₆ H ₅

CH ~C-CH ₂ OH

CH ~ CC (CH ₃ ) ₂ OH

CH ~ C-CH ₂ OC ₄ H ₉

CH ~C-CO ₂ H

CH ~ C-CO ₂ C ₂ H ₅ and

CH ~ C-CH ₂ C ₂ CNHC ₁₈ H ₃₇ .

Examples of oligomeric / polymeric organic compounds (4) are those oligomers / polymers that are reactive Multiple bond related to the hydrosilylation reaction contain. In particular, these are those started with allyl alcohol Polyether, subsequently allylated with alkanols Polyether, polycaprolactam started with allyl alcohol, and Olefins and acrylates that are anionically polymerized and with an unsaturated cationic compound such as Dimethylvinylchlorosilane, can be terminated.

Optionally, olefins such as e.g. B. isobutene is also cationic polymerized and with an anionic compound such as a Alkenylgrignard, to be terminated according to the invention to produce used connections (4).

In the second process step, a type of compound (4) or different types of connection (4) can be used. One or more connections (4) can be made simultaneously or can be used one after the other and therefore several various functions in the branched according to the invention Organosiloxane (co) polymers can be incorporated.

In the second process step, the organic compound (4) used in such quantities that the ratio of aliphatic double bond in (4a) or aliphatic Triple bond in (4b) to Si-bonded hydrogen in the im intermediate obtained in the first process step (5) is preferably 0.5 to 2.0, preferably 1.05 to 2.0.

The compound (4) can be stoichiometric in excess or Deficit, based on the intermediate (5), used become. If a substoichiometric amount (4) is used, branched organosiloxane (co) polymers are obtained which additionally to the functional group Z introduced via (4) contain reactive SiH groups. A preferred version for the production of the branched according to the invention Organosiloxane (co) polymers is the use of at least an equimolar amount of (4), i.e. the use of the same or more of the reactive multiple bonds in (4), based on the SiH groups in (5). A preferred stoichiometric ratio is therefore in the range of 1.05 to 2.0.

When performing the second step, it is possible, compound (4) to the catalyzed intermediate (5) to dose or vice versa. However, the submission of the Compound (4) with catalyst (3), followed by the intermediate (5) is dosed. Provided the warmth of this Hydrosilylation reaction is rather low, will be advantageous Mixture of (4) and (5) at a suitable temperature with Catalyst (3) started, with adiabatic driving the heating of the reaction mixture is a measure of the Progress of the reaction itself is.

If the compound (4) is volatile, the excess Compound (4) are removed by distillation, otherwise remains them in the final product.

The catalyst (3) is in the second process step preferably in amounts of 0.5 to 50 ppm by weight (parts by weight per million parts by weight), preferably in amounts of 2 to 20 ppm by weight, each calculated as elemental platinum and related on the total weight of organic compound (4) and in intermediate obtained in the first process step (5) used.

The second process step is preferably when printing the surrounding atmosphere, i.e. at around 1020 hPa (abs.), performed, but it can also be done at higher or lower Pressures are carried out. Furthermore, the first Process step preferably at a temperature of 20 ° C. up to 150 ° C, preferably 40 ° C to 120 ° C, carried out.

Examples of the branched organosiloxane (co) polymers according to the invention are:
If 1,2,4-trivinylcyclohexane (I) is reacted with H (Me ₂ SiO) ₇ Me ₂ SiH (2) in the first process step and the intermediate product (5) containing Si-bonded hydrogen atoms obtained in the first process step with 1 in the second process step -Octen (4) is reacted, for example a compound of the formula is obtained (Me = methyl radical):

If methyltrivinylsilane (I) is reacted with H (Me ₂ SiO) ₁₉₀ Me ₂ SiH (2) in the first process step and intermediate (5) containing 3-methylbut-1-yne containing hydrogen atoms obtained in the first process step in the second process step -3-ol of the formula HC ~ CC (Me ₂ ) -OH (4) is reacted, for example a compound of the formula is obtained:

To produce the branched according to the invention Organosiloxane (co) polymers can steps 1 and 2 of inventive method also performed simultaneously become what depending on the type of compounds (1), (2) and (4) Products with modified properties may result, provided this is desired.

Likewise, steps 1 and 2 can be done in reverse order be performed. Here, organopolysiloxane (2) in Excess with compound (4) in the presence of catalyst (3) implemented and then the Si-bonded hydrogen atom containing intermediate with compound (1) in the presence of Catalyst (3) implemented. To reverse with the procedure Order of products with comparable product properties how to obtain with the normal preferred method a corresponding adjustment of the proportions of the used compounds (1), (2) and (4) required. If the catalyst (3) is active over the 1st Retains procedural step, can be used for the 2nd procedural step there is also no further addition of catalyst (3) become.

Such branched antimisting additives are preferred Organosiloxane (co) polymers used that are particularly high Have branches. The extent of the branches is shown in the step in which compound (1) is implemented. Preferred additives are obtained when given in the particularly preferred stoichiometric areas worked becomes.

The antimisting additives according to the invention are used for reduction the aerosol formation the crosslinkable Silicone coating compositions added.

The antimisting additives according to the invention, the branched Organosiloxane (co) polymers are used in the crosslinkable Silicone coating compositions, preferably in amounts from 0.5 to 10% by weight, preferably 1 to 5% by weight, based on the total weight of the networkable Silicone coating compositions used.

• A) Organosiliciumverbindungen, die Reste mit aliphatischen Kohlenstoff-Kohlenstoff-Mehrfachbindungen aufweisen,
• B) Organosiliciumverbindungen mit Si-gebundenen Wasserstoffatomen
• C) Die Anlagerung von Si-gebundenem Wasserstoff an aliphatische Mehrfachbindung fördernde Katalysatoren

und gegebenenfalls

• A) Inhibitoren

eingesetzt. Crosslinkable silicone coating compositions are preferably those containing

• A) organosilicon compounds which have residues with aliphatic carbon-carbon multiple bonds,
• B) Organosilicon compounds with Si-bonded hydrogen atoms
• C) The addition of Si-bonded hydrogen to aliphatic multiple bond-promoting catalysts

and if necessary

• A) inhibitors

used.

• A) erfindungsgemäße Antimisting Additive
• B) Organosiliciumverbindungen, die Reste mit aliphatischen Kohlenstoff-Kohlenstoff-Mehrfachbindungen aufweisen,
• C) Organosiliciumverbindungen mit Si-gebundenen Wasserstoffatomen
• D) Die Anlagerung von Si-gebundenem Wasserstoff an aliphatische Mehrfachbindung fördernde Katalysatoren

und gegebenenfalls

• A) Inhibitoren

The invention further relates to crosslinkable silicone coating compositions containing reduced aerosol formation

• A) antimisting additives according to the invention
• B) organosilicon compounds which have residues with aliphatic carbon-carbon multiple bonds,
• C) Organosilicon compounds with Si-bonded hydrogen atoms
• D) The attachment of Si-bonded hydrogen to aliphatic multiple bond-promoting catalysts

and if necessary

• A) inhibitors

The crosslinkable silicone coating compositions can preferably a type of antimisting according to the invention Additive (X) or various types of the invention Antimisting additives (X) can be used.

Linear or branched organopolysiloxanes composed of units of the general formula are preferably used as organopolysiloxanes (A) which have residues with aliphatic carbon-carbon multiple bonds


wherein R ^{5 is} a monovalent, optionally substituted, aliphatic carbon-carbon multiple bonds free hydrocarbon radical having 1 to 18 carbon atoms per radical and
R ⁶ denotes a monovalent hydrocarbon radical with a terminal, aliphatic carbon-carbon multiple bond with 2 to 8 carbon atoms per radical,
z 0, 1, 2 or 3,
y 0, 1 or 2
and the sum z + y is 0, 1, 2 or 3,
with the proviso that an average of at least 1.5 residues R ⁶ ,
preferably an average of at least 2 radicals R ⁶ are present,
used.

Preferred organosilicon compounds (A) are organopolysiloxanes of the general formula

R ⁶ _g R ⁵ _3-g SiO (SiR ⁵ ₂ O) _v (SiR ⁵ R ⁶ O) _w SiR ⁵ _3-g R ⁶ _g (III)

where R ⁵ and R ^{6 have} the meaning given above,
g 0, 1 or 2,
v 0 or an integer from 1 to 1500 and
w is 0 or an integer from 1 to 200,
with the proviso that an average of at least 1.5 radicals R ⁶ , preferably an average of at least 2 radicals R ⁶ , are contained.

In the context of this invention, formula (III) should be understood such that v units - (SiR ⁵ ₂ O) - and w units - (SiR ⁵ R ⁶ O) - can be distributed in any way in the organopolysiloxane molecule.

Branched ones can also be used as organosilicon compounds (A) Polymers with terminal ω-alkenyl groups, preferably Si bound vinyl groups as described in US 6,034,225 (incorporated by reference), in particular column 1, line 43 to column 2, Line 13, and US 6,258,913 (incorporated by reference), in particular column 1, line 62 to column 2, line 35, are used.

Linear organosilicon compounds (A) can also be used Organopolysiloxanes as described in US 6,274,692 (incorporated by reference), in particular column 2, lines 3 to 27 and are not aliphatic at both ends unsaturated hydrocarbon residue, such as a Si-bonded Vinyl group, but also have aliphatic at the ends saturated hydrocarbon residues such as Si-bonded Have methyl groups are used.

Organosilicon compounds (A) can also be those such as in US-A 5,241,034 (incorporated by reference), in particular Column 16, line 23 to column 17, line 35, DE-A 195 22 144 (incorporated by reference), in particular page 2, line 44 to 67, DE-A 196 29 053 (incorporated by reference), in particular Page 2, line 51 to page 3, line 29, US-A 5,760,145 (incorporated by reference), in particular column 2, line 46 to column 4, line 23 and US-A 6,265,497 (incorporated by reference), in particular column 2, lines 3 to 47 are used.

The organopolysiloxanes (A) preferably have one Average viscosity from 100 to 10,000 mPa.s at 25 ° C.

Examples of hydrocarbon radicals R ⁵ are alkyl radicals, such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl -, neo-pentyl, tert-pentyl; Hexyl radicals, such as the n-hexyl radical; Heptyl residues, such as the n-heptyl residue; Octyl radicals, such as the n-octyl radical and iso-octyl radicals, such as the 2,2,4-trimethylpentyl radical; Nonyl radicals, such as the n-nonyl radical; Decyl radicals, such as the n-decyl radical, dodecyl radicals, such as the n-dodecyl radical; Octadecyl radicals, such as the n-octadecyl radical; Cycloalkyl radicals, such as cyclopentyl, cyclohexyl, cycloheptyl radicals and methylcyclohexyl radicals; Aryl radicals such as the phenyl, naphthyl, anthryl and phenanthryl radical; Alkaryl groups such as o-, m-, p-tolyl groups, xylyl groups and ethylphenyl groups; and aralkyl radicals such as the benzyl radical, the α- and the β-phenylethyl radical.

Examples of radicals R ⁶ are alkenyl radicals, such as the vinyl, 5-hexenyl, allyl, 3-butenyl and 4-pentenyl radical; and alkynyl radicals such as the ethynyl, propargyl and 1-propyne radical.

Linear, cyclic or branched organopolysiloxanes composed of units of the general formula are preferably used as organosilicon compounds (B) which have Si-bonded hydrogen atoms


in which
R ^{5 has} the meaning given above,
e 0, 1, 2 or 3,
f 0, 1 or 2
and the sum of e + f is 0, 1, 2 or 3,
with the proviso that an average of at least 2 Si-bonded hydrogen atoms are used.

The organosilicon compounds (B) preferably contain at least 3 Si-bonded hydrogen atoms.

Preferred organosilicon compounds (B) are organopolysiloxanes of the general formula

H _h R ⁵ _3-h SiO (SiR ⁵ ₂ O) _o (SiR ⁵ HO) _p SiR ⁵ _3-h H _h (V)

where R ^{5 has} the meaning given above,
h 0, 1 or 2,
o 0 or an integer from 1 to 1500 and
p is 0 or an integer from 1 to 200,
with the proviso that an average of at least 2 Si-bonded hydrogen atoms are used.

In the context of this invention, formula (V) should be understood such that o units - (SiR ⁵ ₂ O) - and p units - (SiR ₅ HO) - can be distributed in any way in the organopolysiloxane molecule.

Examples of such organopolysiloxanes are in particular Copolymers of dimethylhydrogensiloxane, Methylhydrosiloxane, dimethylsiloxane and Trimethylsiloxane units, copolymers of Trimethylsiloxane, dimethylhydrogensiloxane and Methylhydrosiloxane units, copolymers from Trimethylsiloxane, dimethylsiloxane and Methylhydrosiloxane units, copolymers from Methylhydrogensiloxane and trimethylsiloxane units, Copolymers of methylhydrogensiloxane, diphenylsiloxane and trimethylsiloxane units, copolymers Methylhydrogensiloxane, dimethylhydrogensiloxane and Diphenylsiloxane units, copolymers from Methylhydrosiloxane, phenylmethylsiloxane, trimethylsiloxane and / or Dimethylhydrosiloxane units, copolymers from Methylhydrosiloxane, dimethylsiloxane, diphenylsiloxane, Trimethylsiloxane and / or dimethylhydrogensiloxane units as well as copolymers of dimethylhydrogensiloxane, Trimethylsiloxane, phenylhydrosiloxane, dimethylsiloxane and / or phenylmethylsiloxane units.

Organosilicon compounds (B) which can be used are those such as in US-A 5,691,435 (incorporated by reference), in particular Column 3, line 45 to column 4, line 29, are described, be used.

The organopolysiloxanes (B) preferably have one Average viscosity from 10 to 1,000 mPa.s at 25 ° C.

Organosilicon compound (B) is preferably used in amounts of 0.5 to 3.5, preferably 1.0 to 3.0 gram atom of Si-bonded Hydrogen per mole of Si-bonded residue with aliphatic Carbon-carbon multiple bond in the Organosilicon compound (A) used.

As the attachment of Si-bonded hydrogen Catalysts which promote aliphatic multiple bonds can also with the crosslinkable silicone coating compositions the same catalysts are used, which so far to promote the attachment of Si-bonded hydrogen aliphatic multiple bond could be used. As Constituent (C) are preferably those mentioned above Catalysts (3) used.

The catalysts (C) are preferably used in amounts of 10 to 1000 ppm by weight (parts by weight per million parts by weight), preferably 50 to 200 ppm by weight, each calculated as elemental platinum metal and based on the total weight of the Organosilicon compounds (A) and (B) used.

The crosslinkable silicone coating compositions can the attachment of Si-bonded hydrogen to aliphatic Multiple binding agents delaying room temperature, so-called inhibitors (D) contain.

Inhibitors (D) can also be used in the crosslinkable Silicone coating compositions all inhibitors can be used so far for the same purpose could be used.

Examples of inhibitors (D) are 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, benzotriazole, dialkylformamides, alkylthioureas, methylethylketoxime, organic or organosilicon compounds with a boiling point of at least 25 ° C. at 1012 mbar (abs.) and at least one aliphatic triple bond, such as 1-ethynylcyclohexan-1-ol, 2-methyl-3-butyn-2-ol, 3-methyl-1-pentin-3-ol, 2,5-dimethyl-3-hexin-2 , 5-diol and 3,5-dimethyl-1-hexin-3-ol, 3,7-dimethyl-oct-1-in-6-en-3-ol, a mixture of diallyl maleate and vinyl acetate, maleic acid monoesters, and inhibitors as the compound of the formula HC ~ CC (CH ₃ ) (OH) -CH ₂ -CH ₂ -CH = C (CH ₃ ) ₂ , commercially available under the trade name "Dehydrolinalool" from BASF.

If inhibitor (D) is also used, it is expediently used in Amounts of preferably 0.01 to 10% by weight, preferably 0.01 to 3 wt .-%, based on the total weight of the Organosilicon compounds (A) and (B) used.

Examples of further components that are used in the crosslinkable Silicone coating compositions can also be used can, means for adjusting the separation force, organic Solvents, adhesion promoters and pigments.

Examples of means for adjusting the release force of the coatings repelling sticky substances produced with the compositions according to the invention are silicone resins composed of units of the formula

R ⁷ R ⁵ ₂ SiO _1/2 and SiO ₂ ,

So-called MQ resins, where R ^{7 is} a hydrogen atom, a hydrocarbon radical R ⁵ such as methyl radical, an alkenyl radical R ⁶ such as vinyl radical, and R ⁵ and R ^{6 have} the meaning given above and the units of the formula R ⁷ R ⁵ ₂ SiO _{1/2 can be the} same or different. The ratio of units of the formula R ⁷ R ⁵ ₂ SiO _1/2 to units of the formula SiO ₂ is preferably 0.6 to 2. The silicone resins are preferably used in amounts of 5 to 80% by weight, based on the total weight of the organosilicon compounds (A) and (B) used.

Examples of organic solvents are gasolines, e.g. B. Alkane mixtures with a boiling range from 70 ° C to 180 ° C, n- Heptane, benzene, toluene and xylenes, halogenated alkanes with 1 to 6 carbon atoms, such as methylene chloride, trichlorethylene and perchlorethylene, ethers such as di-n-butyl ether, esters such as Ethyl acetate, and ketones such as methyl ethyl ketone and cyclohexanone.

If organic solvents are used, they will expedient in amounts of preferably 10 to 90% by weight, preferably 10 to 70 wt .-%, based on the total weight of the Organosilicon compounds (A) and (B) used.

The order in which ingredients (X), (A), (B), While (C) and optionally (D) is not critical, for In practice, however, it has proven its worth, component (C) the catalyst, the mixture of the other components last add.

The compositions of the invention are crosslinked preferably at 70 ° C to 180 ° C. As energy sources for the Crosslinking by heating are preferably ovens, e.g. B. Circulating air drying cabinets, heating ducts, heated rollers, heated Plates or heat rays of the infrared range are used.

The compositions according to the invention can, besides Heating by exposure to ultraviolet light or by Irradiation can be cross-linked with UV and IR light. As Ultraviolet light is usually one with a Wavelength of 253.7 nm used. There is one in the trade Variety of lamps that use ultraviolet light Emit wavelength of 200 to 400 nm, and the Ultraviolet light with a wavelength of 253.7 nm is preferred emit.

The invention furthermore produces moldings by crosslinking the compositions according to the invention.

The shaped bodies are preferably Coatings, preferably to repel sticky substances Coatings.

The invention further relates to a method for Manufacture of coatings by applying crosslinkable compositions according to the invention to the coating surfaces and subsequent crosslinking of the Compositions.

The crosslinkable compositions according to the invention are preferred for the production of repellent sticky substances Coatings, e.g. B. used for the production of release papers. Coatings that repel sticky substances are produced by Application of crosslinkable compositions according to the invention surfaces to be made repellent to the sticky substances and subsequent crosslinking of the compositions.

The application of the compositions according to the invention the surfaces to be coated, preferably sticky substances surfaces to be made repellent, can be in any, for which Production of coatings from liquid substances more suitable and done in a well known manner, for example by Dip, brush, pour, spray, roll, print, e.g. B. by means of an offset engraving coating device, knife or Squeegee coating or using an air brush.

The layer thickness on the surfaces to be coated is preferably 0.3 to 6 µm, particularly preferably 0.5 to 2.0 µm.

The surfaces to be coated, preferably surfaces which are to be made repellent to sticky substances and which can be treated in the context of the invention, can be surfaces of any solid substances at room temperature and 1012 mbar (abs.). Examples of such surfaces are those of paper, wood, cork and plastic films, e.g. B. polyethylene films or polypropylene films, woven and non-woven cloth made of natural or synthetic fibers, ceramic articles, glass, including glass fibers, metals, paper coated with polyethylene and cardboard, including those made of asbestos. The polyethylene mentioned above can each be high, medium or low pressure polyethylene. Paper can be inferior types of paper, such as absorbent papers, including raw kraft paper with a weight of 60 to 150 g / m ² not pretreated with chemicals and / or polymeric natural substances, unsized papers, papers with low freeness, wood-containing papers, non-calendered or non-calendered papers, papers that are smooth on one side due to the use of a dry smoothing cylinder during their production without further complex measures and are therefore referred to as "one-sided machine-smooth papers", uncoated papers or papers made from paper waste, i.e. so-called waste papers , act. The paper to be treated according to the invention can, of course, also be high-quality paper types, such as low-suction papers, sized papers, papers with a high degree of grinding, wood-free papers, calendered or satined papers, glassine papers, parchmentized papers or pre-coated papers. The cardboards can also be of high or low quality.

The compositions according to the invention are suitable for example for the manufacture of separating, covering, and Follow-up papers, including follow-up papers that are used by Production of e.g. B. cast or decorative films or Foams, including those made of polyurethane, are used become. The compositions according to the invention are suitable furthermore for example for the production of separating, covering, and idler cardboards, foils, and cloths for the equipment the back of self-adhesive tapes or self-adhesive Foils or the labeled sides of self-adhesive Labels. The compositions according to the invention are suitable also for the equipment of packaging material, such as such made of paper, cardboard boxes, metal foils and barrels, e.g. B. Cardboard, plastic, wood or iron for storage and / or Transport of sticky goods, such as glue, sticky Foods, e.g. B. cakes, honey, candy and meat; Bitumen, asphalt, greased materials and raw rubber, determined is. Another example of using the compositions according to the invention is the finishing of Carriers for transferring pressure-sensitive adhesive layers in the so-called "Transfer process".

Those containing the anti-misting additives according to the invention crosslinkable silicone coating compositions are suitable especially for use in fast coating systems with coating speeds preferably from 300 to 1500 m / min, preferably 400 to 1000 m / min, at which the compositions according to the invention at high speeds are applied to the surfaces to be coated.

The compositions according to the invention are suitable for Manufacture of the associated with the release paper Self-adhesive materials both using the off-line process and even after the in-line process.

In the off-line process, the silicone composition is applied to the Paper applied and cured, then, in a subsequent one Level, usually after winding the release paper on a Roll and after storing the roll, an adhesive film, which lies on a label face paper, for example the coated paper is applied and the composite is then compressed. In the in-line process, the Silicone composition applied to the paper and crosslinked, the silicone coating is coated with the adhesive that Label face paper is then applied to the adhesive and the composite finally pressed together.

In the off-line process, the Winding speed according to the time required to coat the silicone to make it tack free. In the in-line process, the Process speed according to the time necessary to to make the silicone coating migration-free. The off-line Procedure and the in-line procedure can with the compositions of the invention at a rate from 300 to 1500 m / min, preferably 400 to 1000 m / min, operated become.

Examples 1

In a glass flask with mechanical stirrer, 108 g of 1,2,4-trivinylcyclohexane with 1840 g of an α, ω-dihydrogenpolydimethylsiloxane with an active hydrogen content (Si-bonded hydrogen) of 0.18% by weight (SiH / C = C = 1.66) and a viscosity of 9 mPa.s at 25 ° C. and then 1.9 g of a solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex in an α, ω-divinyldimethylpolysiloxane with a viscosity of 1000 mPa.s at 25 ° C with a Pt content of 1.0 wt .-% (so-called Karstedt catalyst, the production of which is described in US 3,775,452) was added. The reaction mixture heats up to about 80 ° C. in a few minutes and is stirred at this temperature for about 1 h. A branched siloxane polymer having a viscosity of 220 mm ² / s at 25 ° C. and an active hydrogen content of 0.067% by weight is obtained. According to the principle of synthesis, all free siloxane chain ends consist of the highly reactive hydrogendimethylsiloxy units.

Example 2

672 g (450 mmol SiH) of the hydrogen siloxane polymer prepared in Example 1 are mixed turbulently with 1025 g (585 mmol C = C) of a monoallyl-terminated polyether from the same molar amounts of ethylene oxide and propylene oxide (C = C / SiH = 1.3) and at 100 ° C warmed. Then 3.5 g of a hexachloroplatinic acid solution in isopropanol (0.48% Pt) are added. With slight exotherm, the mixture becomes homogeneous after approx. 10 minutes. The mixture is stirred for a further 3 h at 100 ° C. and a strongly branched polyether siloxane with a viscosity of 14,970 mm ² / s (25 ° C.) is then obtained. The 1H-NMR spectrum shows an SiH conversion of approx. 99%.

Example 3

672 g of the hydrogen siloxane polymer prepared in Example 1 are heated to 100 ° C. A mixture of 90 g propoxylated allyl alcohol with an iodine number of 110 (231 g polyether / mol C = C) and 2.2 g hexachloroplatinic acid solution (0.48% Pt) is slowly run in and allowed to react for 2 hours (C = C / SiH = 1 , 16). After complete consumption of SiH, a clear oil with a viscosity of 520 mm ² / s at 25 ° C. is obtained.

Example 4

To produce a highly branched OH-terminated siloxane without polyether groups, Example 2 is repeated analogously, in which instead of 1025 g of allyl polyether, only 43 g of 2-methyl-3-buten-2-ol are used (C = C / SiH = 1.11). Complete SiH conversion is obtained in less than 1 h at 100 ° C. The excess of 5 g tert. Alcohol is removed at 120 ° C., whereupon a clear multihydroxysiloxane polymer with a viscosity of 410 mm ² / s (25 ° C.) is obtained.

Example 5

Siloxane polymers with even higher branching can be made be by an already highly branched Hydrogen siloxane polymer with a small amount of one Divinyl compound is further implemented. 384 g of the in example 1 polymer produced with 44 g of α, ω-divinylsiloxane average molecular weight of 1104 (Mn) homogeneously mixed and Maintained at 100 ° C for 4 h.

The original viscosity of the hydrogen siloxane polymer subsequently increases to 1100 mm ² / s at 25 ° C., the content of active hydrogen (Si-bonded hydrogen) drops to 0.052% by weight.

50% of the mixture are mixed with 25 g of 1-octene (C = C / SiH = 2.0) and heated to 100 ° C, a slightly exothermic reaction starting. After 1 h, excess octene is removed in vacuo. A clear, very highly branched oil with a viscosity of 1330 mm ² / s at 25 ° C. is obtained.

Example 6

The second half of the higher-branched hydrogen siloxane polymer prepared in Example 5 with 0.052% by weight of Si-bonded hydrogen is mixed with 55 g of 1-octadecene (C = C / SiH = 2.0) and heated to 100 ° C. for 1 hour , The siloxane polymer according to the invention is diluted by excess olefin, which cannot be removed under standard vacuum at 100 ° C., and therefore has a viscosity of only 900 mm ² / s at 25 ° C.

Example 7

Products of higher viscosity according to the invention are also available if more triene (SiH / C = C = 1.56) is used in the production of the hydrogen component. Therefore, if Example 1 is repeated with 115 g of 1,2,4-trivinylcyclohexane (instead of only 108 g), a more branched siloxane polymer with 750 mm ² / s (25 ° C.) and a content of Si-bonded hydrogen is obtained only 0.060% by weight.

200 g of this product are mixed with 27 g of 1-octene (C = C / SiH = 2.0) and allowed to react at 100 ° C in a weakly exothermic reaction. Excess octene is removed after 2 hours in vacuo, whereupon a clear oil with a viscosity of 1870 mm ² / s at 25 ° C. is obtained.

Use of the branched siloxane (co) polymers as antimisting additives Example 8

With high order weight and certain Aerosol formation can already contribute to coating formulations Machine speeds well below 500 m / min occur. The use of the branched according to the invention Siloxane copolymers to reduce aerosol formation were made as Additive in crosslinkable silicone coating systems for the Use in such coating processes.

A mixture of was used as the standard formulation
100 parts by weight of a branched polysiloxane with vinyldimethylsiloxy end groups, which has a viscosity of 420 mPa.s (25 ° C.) and an iodine number of 8.0 and is produced in accordance with Example 3 of US Pat. No. 6,034,225,
3.6 parts by weight of a linear polysiloxane composed of hydrogenmethylsiloxane and trimethylsiloxane units in a molar ratio of 24: 1,
1.04 parts by weight of a 1 wt .-% (based on elemental platinum) solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex in an α, ω-divinyldimethylpolysiloxane with one Viscosity of 1000 mPa.s at 25 ° C and
0.3 part by weight of 1-ethynylcyclohexanol
used.

The additives of the invention according to those in the table given manufacturing examples were the Standard formulation according to the ones given in the table Amounts added. As a comparison, a standard formulation was used used without additive according to the invention. These blends were used for paper coating.

Paper from Ahlstrom with the designation Glassine Larice Tipo 325 with 62 g / m ^{2 was} used as the substrate. The coating was carried out on the pilot coating system from Dixon, model number 1060, with a 5-roll coating unit, at 150 m / min. The job roll was run at 95% of the paper speed. The coating was cured in a drying oven with a length of 3 m at 140 ° C.

Aerosol formation was determined using the Dusttrak Aerosol Monitor Model 8520. Samples were taken between the silicone application roller and the nip at a distance of 12 cm from the silicone application roller. In addition, the aerosol formation was assessed visually and rated with the numbers 1-3:
1 no visible aerosol formation
2 weakly visible aerosol formation
3 strong aerosol formation.

The maximum displayed aerosol values were recorded during the coating tests. The coating weight was determined by means of X-ray fluorescence analysis in reference to a suitable standard and was 2.5 g / m ² .

The results are summarized in the table. table

The comparative experiments show that the addition of branched organic end functions according to the invention having siloxane (co) polymers as antimisting additives Aerosol formation of crosslinkable silicone coating systems in rapid coating processes significantly reduced.

Claims (15)

1. Use of antimisting additives in crosslinkable silicone coating compositions to reduce aerosol formation, characterized in that branched organosiloxane (co) polymers containing structural elements of the formula are used as antimisting additives

Y [-C _n H _2n - (R ₂ SiO) _m -A _p -R ₂ Si-G] _x (I)

in which
Y represents a trivalent to ten-valent hydrocarbon radical, which can contain one or more heteroatoms selected from the group of oxygen, nitrogen and silicon atoms,
R can be the same or different and represents a monovalent optionally halogenated hydrocarbon radical having 1 to 18 carbon atoms per radical,
A represents a radical of the formula -R ₂ Si-R ² - (R ₂ SiO) _m -,
where R ^{2 is} a divalent hydrocarbon radical having 2 to 30 carbon atoms, which can be interrupted by one or more oxygen atoms which are separate from one another,
G denotes a monovalent radical of the formula -C _f H _2f-2k -Z or a divalent radical of the formula -C _n H _2n -, where the second bond is to a further radical Y,
Z is a monovalent hydrocarbon radical free from terminal aliphatic carbon-carbon multiple bonds, which is inert to SiH groups in hydrosilylation reactions and can contain one or more heteroatoms selected from the group consisting of oxygen, nitrogen, boron, silicon and titanium,
or represents a monovalent polymer radical with more than 20 carbon atoms,
x is an integer from 3 to 10,
f is an integer from 2 to 12,
k is 0 or 1
n is an integer from 2 to 12,
m is an integer of at least 1 and
p is 0 or an integer positive number,
with the proviso that the branched organosiloxane (co) polymers contain on average at least one group Z,
be used. 2. Use according to claim 1, characterized in that x 3 or 4. 3. Use according to claim 1 or 2, characterized in that that p is 0. 4. Use according to claim 1, 2 or 3, characterized characterized in that the ratio of end groups Z to Branching groups Y is 1.0 to 2.0. 5. Use of antimisting additives in crosslinkable silicone coating compositions to reduce aerosol formation, characterized in that
As antimisting additives, branched organosiloxane (co) polymers can be produced by in a first step
at least three compounds (1) of the formula which have aliphatic double bonds
Y (CR ¹ = CH ₂ ) _x
where Y and x have the meaning given in claim 1 and
R ^{1 represents} a hydrogen atom or an alkyl radical having 1 to 10 carbon atoms
with organopolysiloxanes (2) of the general formula
H (R ₂ SiO) _m -A _p -R ₂ SiH
where A, R, m and p have the meaning given for them in claim 1,
in the presence of catalysts which promote the attachment of Si-bonded hydrogen to aliphatic multiple bonds (3),
be implemented
and in a second step the branched intermediates (5) thus obtained containing Si-bonded hydrogen atoms with organic compounds (4) of the formula

C _f H _2f-2k-1 -Z

selected from the group of
if k = 0:

H ₂ C = CR ³ -Z (4a) and

if k = 1:

R ⁴ C ~ CZ (4b)

wherein R ³ and R ^{4 have} the meaning of R ¹ , and
f, k and Z have the meaning given for this in claim 1,
in the presence of catalysts which promote the attachment of Si-bonded hydrogen to aliphatic multiple bonds (3),
be implemented
be used. 6. Use according to claim 5, characterized in that 1,2,4-trivinylcyclohexane is used as compound (1). 7. Use according to claim 5 or 6, characterized in that that the organopolysiloxane (2) in the first process step is used in such quantities that the ratio of Si-bonded hydrogen in organopolysiloxane (2) aliphatic double bond in compound (1) at least Is 1.5. 8. Use according to claim 5, 6 or 7, characterized characterized in that the organic compound (4) in second process step used in such quantities is that the ratio of aliphatic double bond in (4a) or aliphatic triple bond in (4b) to Si bound hydrogen in the first step Intermediate (5) obtained is 1.05 to 2.0. 9. Use according to one of claims 1 or 8, characterized in that containing such as a crosslinkable silicone coating composition A) organosilicon compounds which have residues with aliphatic carbon-carbon multiple bonds, B) Organosilicon compounds with Si-bonded hydrogen atoms C) The addition of Si-bonded hydrogen to aliphatic multiple bond-promoting catalysts and if necessary A) inhibitors be used. 10. Containing crosslinkable silicone coating composition with reduced aerosol formation A) Antimisting additives according to one of claims 1 to 4 or producible according to one of claims 5 to 8 B) organosilicon compounds which have residues with aliphatic carbon-carbon multiple bonds, C) Organosilicon compounds with Si-bonded hydrogen atoms D) The attachment of Si-bonded hydrogen to aliphatic multiple bond-promoting catalysts and if necessary A) inhibitors 11. Molded articles produced by crosslinking the Compositions according to claim 10. 12. Shaped body according to claim 11, characterized in that it is coatings. 13. Shaped body according to claim 11, characterized in that it is sticky-repellent coatings. 14. Process for the production of coatings Application of crosslinkable compositions according to claim 10 on the surfaces to be coated and subsequent Crosslinking of the compositions. 15. Process for making sticky repellant Coatings by applying crosslinkable compositions repellent to the sticky substances according to claim 10 surfaces and subsequent networking of the Compositions.