FR2608617A1 - COMPOSITION CONTAINING A DIALKYL ACETYLENEDICARBOXYLATE AS AN INHIBITOR FOR FORMING BY EXPOSURE TO ULTRAVIOLET LIGHT A NON-STICK COATING OF SILICONE AND A METHOD OF USING THE SAME TO PRODUCE ANTIADHESIVE SURFACES - Google Patents

Abstract

COMPOSITION CONTAINING CURABLE polyorganosiloxane CATALYZED ADDITION AND PLATINUM COATING FORMING A NON-STICK CONTAINS acetylenedicarboxylate DIALKYL AS INHIBITORS PREMATURE TO AVOIDING THE JELLIFICATION TEMPERATURES, BUT FOR THE CURE EXPOSURE TO LIGHT ULTRAVIOLET ACCORDING hydrosilation reaction, TO FORM A COATING WHICH MAKES MATERIAL NORMALLY ADHESIVE TO SUBSTRATES DO NOT ADHER.

Description

The present invention relates to a composition containing as an inhibitor

  a dialkyl acetylenedicarboxylate to form, by exposure to ultraviolet light, a nonstick silicone coating, and a method using it to produce nonstick surfaces. More particularly, the present invention relates to ultraviolet light activated curing of additionally cured platinum catalyzed silicone coatings which contain

  as inhibitors of dialkyl acetylenedicarboxylates.

  The silicone compositions curable by reaction of

  -SiH groups with olefinic groups bonded to silicone in pre-

  sence of a hydrosilation catalyst are well known in the art and are for example described in US Pat. Nos. 2,813,218, 3,249,581 and 3,436,366. As the curing begins when the aforementioned ingredients are mixed, is customary to provide the compositions curable by addition in two packages, one of which contains the olefinically unsaturated polysiloxane and the hydrosilation catalyst and the other contains the crosslinking agent constituted

an organohydrogenopolysiloxane.

  When it is necessary to increase the pot life of the addition curable organopolysiloxane compositions, or

  providing an additive curable organopolysiloxane composition

  tion with a single component, a dur-

  cisse. Generally, hardening inhibitors are

  compounds that slow curing at ambient temperatures

  but which do not delay hardening at high temperatures

  vee. These hardening inhibitors are hardening inhibitors.

  heat deactivated or are sufficiently volatile to be removed from the coating compositions at elevated temperature. Specific hardening inhibitors deactivated by

  heat are dialkyl acetylenedicarboxylates. These inhibi-

  -teurs are described in US Patent No. 4,347,346 to the applicant and correspond to the formula ROOCCCCOOR in which R is a radical

monovalent hydrocarbon.

  An object of the invention is to provide formulated compositions

  as a coating of addition hardened and catalyzed platinum silicone containing acetylenedicarboxylate inhibitors

  dialkyls which are curable by ultraviolet light.

  Another object of the invention is to provide a method for

  curing compositions forming a cured silicone coating

  by addition and catalyzed with platinum containing as an inhibitor

  dialkyl acetylenedicarboxylates, which comprises the stage of exposure of the composition forming a coating to ultraviolet light. The present invention provides a silicone composition containing an inhibiting agent, which is a acetylenedicarboxylate of

  dialkyl effective in delaying the hydrosilation reaction of hard

  platinum addition catalyzed curing at temperature

  ordinary, and hardens effectively by exposure to a ray-

  ultraviolet to form a silicone coating which adheres tenaciously to a substrate, such as paper to which it is applied, but makes this substrate essentially non-adhesive for materials

  such as pressure sensitive adhesives which normally adhere to it.

  The composition forming a non-stick coating of the invention

  tion consists of: a. An olefin-organopolysiloxane having structural units of formula: RaR'bSio (4-a-b) (I) and b. an organohydrogenpolysiloxane having structural units of formula: RaHbSio (4-ab) (II) in which R is an organic radical attached to silicon by a C-Si bond and is chosen from the group consisting of monovalent hydrocarbon radicals, radicals halogenated monovalent hydrocarbons and cyanoalkyl radicals; generally R contains 1 to 30 carbon atoms in the form of a

  straight or branched chain, preferably 1 to 12 carbon atoms

  bone and more preferably i to 8 carbon atoms; R 'is a

  olefinic hydrocarbon radical attached to silicon by a bond

  its C-Si and generally contains 1 to 20 carbon atoms ali-

I5

  phatic in the form of a straight or branched chain and of pre-

  ference 1 to 12 carbon atoms linked by multi- bonds

  ples (such as vinyl, allyl, methallyl, butenyl, pentenyl, ethenyl and the like); has a value of 0 to 3 inclusive and preferably of 0.5 to about 2 inclusive, ba a value of 0.005 to 2.0 inclusive and the sum of a and ba a value of 0.8 to 3 inclusive, the composition forming a non-stick coating being, at ordinary temperature, a fluid having a viscosity of about 25 to 500 centipoise and

  preferably 300 to 1,000 centipoise at 25'C.

  vs. an amount of platinum catalyst sufficient to cause the co-reaction of (a) and (b) and d. an amount of dialkyl acetylenedicarboxylate effective for

  inhibit an additive hardening hydrosilation reaction

  tion between said olefin-organopolysiloxane and said organohy-

  drogenopolysiloxane. Dicarboxylate has the general formula

  rale ROOCCECCOOR in which R is as defined above and is present in an amount inhibiting premature gelling of the product of the catalyzed co-reaction of (a) and (b) but is

  present in insufficient quantity to prevent hardening

  ment of said composition forming a coating during

  exposure to ultraviolet radiation.

  The composition of the invention is particularly suitable

  to make materials non-adherent to other materials normal-

  adherent, such as glue and adhesives. In addition, the composition can be applied directly to a substrate without the need for a solvent, which eliminates all associated problems.

coating solvents.

  The composition consists of an organopolysiloxane, made of several constituent ingredients, which adheres to the substrate which is coated with it and exhibits thermosetting therein and makes the substrate

not adhesive.

  The olefin-organopolysiloxanes, having the structural motifs

  The compounds represented by formula I above generally consist of low viscosity fluid organopolysiloxanes suitable for the formation of a coating which, preferably, but

  not necessarily, are free of silane hydrogen and contain

  an unsaturation established by double or triple bonds

  between two adjacent aliphatic carbon atoms. Among the radi-

  caux represented by R in formula I above, include alkyls such as methyl, ethyl, propyl, isopropyl, butyl,

  octyl, dodecyl and the like; cycloalkyls such as cyclopen-

  tyle, cyclohexyl, cycloheptyle and the like; aryls such as phenyl, naphthyl, tolyl, xylyl and the like; aralkyls such as benzyl, phenylethyl, phenylpropyl and the like; drifts

  halogenated radicals, including chloromethyl, trifluoro-

  methyl, chloropropyl, chlorophenyl, dibromophenyl, tetrachloro-

  phenyl, difluorophenyl and the like; and cyanoalkyls such as> cyanoethyl, -cyanopropyl, e-cyanopropyl and the like. Of

  preferably R is methyl. In addition, formula I covers the materials

  res in which R is a mixture of the aforementioned radicals.

  Among the radicals represented by R 'in formula I

  above, there are alkenyls, such as vinyl, allyl, methal-

  lyle, butenyl, pentenyl and the like; and alkynyls, such

  as ethynyl, propynyl, butynyl, pentynyl and the like. Preferably

  rence R 'is a vinyl or an allyl and more preferably R' is a vinyl. The olefin-organopolysiloxanes corresponding to formula I above are well known in the art and appear in particular

  in US Pat. Nos. 3,344,111 and 3,436,366. Similarly, their preparation

  tion and their commercial availability are well known. The olefinorganopolysiloxanes useful in the invention are characterized as copolymers of (1) siloxane units corresponding to the formula: RCR'dSi4_cd (IV) in which R and R 'are as defined above and have a value of 0 to 2 inclusive and the sum of c and da a value of 0.8 to 3.0 inclusive, and (2) organosiloxane units corresponding to the following formula: (R) nSiO4_n (V) in which R is as defined above and has a value of 0.8 to 2.5 inclusive. So the olefinorganopolysiloxane used here

  is a copolymer of units corresponding to formula IV with an organ-

  nopolysiloxane, the average composition of which corresponds to formula V, the copolymer generally containing from 0.5 to 99.5 mol% of units of formula IV and from 0.5 to 99.5 mol% of units of formula V. The

  Preparation of these copolynmers is also well known in the art.

  A major proportion of the composition typically consists of a polysiloxane with vinyl endings corresponding to the general formula: E2C CH-.Si-O i0 1i i-CH = -c2 aaa y in which R is a monovalent hydrocarbon radical lacking

  of unsaturation. Suitable radicals represented by R include

  of unsaturation. Suitable radicals represented by R include

  for example methyl, ethyl, propyl, butyl and other radicals

  similar unsaturated hydrocarbon cals, but generally do not include

  take no phenyl radicals to ensure antiad-

  hesitant to a paper. R 'is a hydrocarbon radical having an unsatu-

  alkenyl ration. Typically, R 'represents vinyl groups, but can also represent allyl or cycloalkenyl unsaturated groups. X and Y are positive integers, so that the vinyl-terminated polysiloxane contains up to about 20% by weight of R 'groups. The viscosity of such a polysiloxane is

  between about 50 and about 100,000 centipoises at 25'C. Preferably

  The vinyl-terminated polysiloxane contains up to about 20% by weight of vinyl groups represented by R 'and the viscosity of this polymer is between about 300 and about 550 centipoise at 25'C. The preferred vinyl terminated polysiloxane corresponds to the general formula:

CH3 CH3 CH3 CH3

  CH2 .-- CH- Si -iO Si- C.H.- CH2 CH2 CH 0 iO 0 Si 2C C CH3 i 3 CE2 CH3

3 CH CH 2

  in which X and Y are as described above.

  A methylhydrogen type fluid is often used by those skilled in the art of silicones as a crosslinking agent for addition hardened silicone systems. A crosslinking agent

  particularly useful in the invention is a polymethylhydrogen-

  trimethyl-terminated fluid siloxane containing about 10% to

  approximately 100% of SiH groups, the remaining groups being essential-

  dimethylsiloxy units and having a viscosity in the

  range from about 25 to about 1,000 centipoise at 25'C.

  Organohydrogenpolysiloxanes having structural motifs

  The amounts represented by formula II above generally comprise the fluid organopolysiloxanes, which, preferably but not necessarily, are free of olefinic unsaturation, but

  which contain silane hydrogen. These organohydrogenopolysilo-

  xanes represented by formula II above are well known in the art and appear in particular in US Pat. Nos. 3,344,111 and

3,436,366.

  Among the radicals represented by R in formula II above, as well as for R in formula I above, there are alkyls such as methyl, ethyl, propyl, isopropyl, butyl, octyl and the like; cycloalkyls such as cyclopentyle,

  cyclohexyl, cycloheptyle and the like; aryls such as phe-

  nyle, naphthyle, tolyle, xylyl and the like; aralkyls such as benzyl, phenylethyl, phenylpropyl and the like; drifts

  halogenated radicals, including chloromethyl, trifluoro-

  methyl, chloropropyl, chlorophenyl, dibromophenyl, tetrachloro-

  phenyl, difluorophenyl and the like; and cyanoalkyls such as 5cyanoethyl, T-cyanopropyl, 5-cyanopropyl and the like. Formula II also covers materials in which R is a

  mixture of the aforementioned radicals. Preferably group R of the form-

mule II is methyl.

  Materials specifically responding to formula II

  above include 1,3-dimethyldisiloxane, 1,1,3,3-tetra-

  methyldisiloxane as well as higher polymers containing up to

  than 100,000 or more silicon atoms per molecule. The subjects

  cyclic, such as cyclic polymers of methylhydrogenosi-

  loxane corresponding to the formula: (CH3SiHO) x in which x is an integer from 3 to 10 or more, also correspond to formula II. Among them is in particular tetramethylcyclotetrasiloxane. The organohydrogenopolysiloxanes used in the practice of the present invention can also be characterized as copolymers containing per molecule at least one unit of formula: RcHdsiO4-cd (VI) the other siloxane units of the organopolysiloxane corresponding to formula V above in which R, c, d and n are defined above. Formula VI also covers siloxane units such as hydrogenosiloxane units (H2SiO) 1.5, methylhydrogenosiloxane units (HSiCH30), dimethylhydrogenosiloxane units and dihydrogenosiloxane units (H2Si). In these copolymers,

  the siloxane units of formulas V and VI are present in a pro-

  portion as it forms a hydrogenopolysiloxane corresponding to formula II above. In general, these copolymers contain from 0.5 to 99.5 mol% of the siloxane units of formula V with 0.5 to

  99.5 mol% of siloxane units of formula VI.

  Ordinarily, to form a non-stick coating,

  prefer that the cross-linking organohydrogenpolysiloxane be essential-

  a methylhydrogenopolysiloxane fluid with trimethyl terminus

  liquids with a viscosity of around 10 to 500 centipoise at 25 ° C and

  a hydrogen content of about 0.1 to 1.67% by weight.

  The precious metal catalytic component employed in the compositions of the invention includes all of the well known platinum catalysts which are effective in catalyzing the reaction between silicon bonded hydrogen groups and bonded olefinic groups

  silicon and which are easily miscible with silicon polymers

  solvent-free cone. These materials include, for example,

  xes platinum-hydrocarbon indicated in US Pat. Nos. 3,159,601

  and No. 3,159,662, as well as the platelet alcoholate catalysts

  tine described in US Patent 3,220,972. In addition, the platinum chloride-olefin complexes described in US Patent 3,516,946

are also useful here.

  Small amounts of inhibitor consisting of acetylenedi-

  dialkyl carboxylate provides an exceptionally long pot life after catalysis, without adversely affecting curing performance in a solvent-free system to form a release paper. Generally, the effective amount of inhibitor is

  is between about 0.05% and about 1.0% by weight and preferably

  between 0.1 and 0.25% by weight. The use of the inhibitor of the invention ensures an appropriate pot life and nevertheless allows the composition to harden quickly in the form of a non-adhesive surface without stains or migration when it is hardened by the

ultraviolet light.

  Dialkyl acetylenedicarboxylates result from the diesterification reaction of 2-butynedicarboxylic acid and

  two equivalents of alcohols such as methanol, ethanol, buta-

  nol, benzyl alcohol, allyl alcohol or mixtures of such alcohols. These reactions can be represented by: HOOCC = CCOOH + 2 ROH - ROOCCsCCOOR + 2 H20 or HOOCCsCCOOH + ROH + R'OH - * ROOCCsCC00R '+ 2 H20

  Useful diesters so prepared include acetylenedicarboxy-

  dimethyl late, diethyl acetylenedicarboxylate, acety-

  dibutyl lenedicarboxylate, methyl acetylenedicarboxylate, methyl and ethyl acetylenedicarboxylate, etc. Diesters

  in which R represents a methyl or ethyl group are particu

  particularly useful in the practice of the invention.

  The effective amounts of dimethyl acetylenedicarboxylate

  thyle are very soluble in silicone fluids and this compound

  is very little volatile, its melting point at atmospheric pressure

  that being greater than 200'C. In addition, dimethyl acetylenedicarboxylate is readily available commercially. Also, since the total concentration of the inhibitor in the polysiloxane inhibited by dimethyl acetylenedicarboxylate is very low, the total cost is significantly reduced. In addition, the small inhibitory amounts of dimethyl acetylenedicarboxylate used in the invention are almost completely included in the crosslinked polymer. There is therefore no dimethyl acetylenedicarboxylate

  free after hardening of the polymer composition.

  Dimethyl acetylenedicarboxylate also effectively inhibits

  curing the curing reaction by condensation catalyzed with platinum of the polysiloxane compositions having a silanol function, just as it inhibits the curing of these compositions having both a silanol function and a vinyl function. A polymer

  base for such a composition can be for example a polydi-

2 608617

  silanol-terminated organosiloxane having side vinyl groups

along the siloxane chain.

  The ingredients described above can be mixed in any order and exposed to ultraviolet radiation to cure. Those skilled in the art are familiar with curing by UV light and can readily determine

  the spectrum, flux and exposure time appropriate to the

hardening.

  The preferred use of the composition described above is the formation of a non-stick coating on a substrate. The composition is mixed, applied as a thin film to a substrate and cured by exposure to ultraviolet light. The substrate may be non-porous, for example made of glass, a thin sheet of plastic or metal, etc., but it is preferably porous, such as paper and other fibrous materials. The following examples are presented by way of illustration but in no way limitative to facilitate those skilled in the art

in practice of the invention.

Example 1

  A linear fluid to term polydimethylsiloxane is mixed

  vinyl house of 500 centipoises with various quantities of a

  Karstedt platinum catalyst and dimethyl acetylenedicarboxylate

  thyle (DIMAC). In two minutes of mixing, each composition pre-

  has an intense orange-yellow color. Table I shows the

  mixed compositions and their content.

Table I

  Concentration Concentration Molar ratio Composition of Pt, ppm of DIMAC, ppm Pt / DIMAC 1 25 i 000 1/55

2 25 250 1 / 13.7

3 40 200 1.6 / 11

4 50 200 2/11

Example 2

  A linear silicone polymer of the dimer type is mixed.

  A linear silicone polymer of the dimer type is mixed.

  thyle and methyl vinyl Vinyl terminated at 400 centipoise, containing 3.7% by weight of Dvi units, with various amounts of a

  Karstedt platinum catalyst and dimethyl acetylenedicarboxylate

  thyle (DINAC). In two minutes of mixing, each composition pre-

  has an intense orange-yellow color. Table II shows the

  compositions that are mixed and their content.

Table II

  Concentration Concentration Molar ratio Pt composition, ppm of DIHAC, ppm Pt / DIMAC

5 50 200 2/11

6 100 300 4 / 16.5

Example 3

  Each of the compositions 1 to 6 is mixed with a poly (dim

  thyl-methylhydrogen) linear siloxane with trimethylsiloxy termination of 350 centipoise, containing 50% by weight of DH units, in a weight ratio of 9 to 1. It is coated with the compound baths 1 to 6

  obtained, substrates made of aluminum panels Q, of a film

  polypropylene or satin kraft paper weighing 18 kg / ream.

  The coated substrates are exposed in an oven or in air to the

  ultraviolet light as shown in Table III.

Table III

  Thickness of the conditions Compo coating Exp-osition of the furnace sition Substrate (mm) UV, J / cm2 min / 'C Qualitative results 1 paper 0.05 1.5 -Hardened, no stain, no migration, good anchoring

1 aluminum 0.05 4.5 .--

1 paper ** Thin film 1.5 ...

  1 aluminum 0.05 - 5/80 "* 1 paper 0.10 1.5 - The exposed areas are hardened, the shaded areas are wet 2 paper Thin film 1.15 - Hardened, no migration, slight stains 2 Thin film paper - 1, 5/80 "3 Thin film paper 0.6 - Hardened, no migration, slight stains 3 Thin film paper 0.48 - Insufficiently hardened, migration 3 Thin film paper - 1/80 Hardened, slight migration 4 paper Thin film 0.6 - Hardened, no migration, slight stains 4 paper Thin film 0.48 - Insufficiently hardened, slight migration paper Thin film 0.96 - Hardened, no migration, light paper stains Thin film 0.64 - Insufficiently hardened, polypro- migration Thin film 1.28 - Poor hardening, migration, bad pylene polypro- anchoring 0.025 2.9 Hardened, no migration, but is removed by pylene rubbing 6 paper thin film 0.96 - hardened, no migration, slight stains 6 paper thin film 0.64 - insufficiently hardened, migrating on * Formation of a shadow across the coating ** The "thin film" measures approximately 5 micrometers The above values show that the -Dviprésents patterns in the basic polymers seem to harden slowly compared to fluids with Mvi function. High platinum concentrations

  do not increase hardening as long as inhi-

DIMAC bitrices are present.

Example 4

  This experiment aims to verify that ultraviolet light

  lette without thermal addition triggers the hardening of additionally hardened Pt / DIMAC systems. There is a low intensity ultraviolet light source (UV Products, Inc. table lamp 115 volts and 0.35 amps) not focused at a distance of 44 mm from an aluminum substrate coated with 0 0.05 mm from the compound bath 1. It is determined that the UV flux is 6 J / cm2.h. You can't detect a noticeable difference between room temperature,

  24'C, and the measured temperature of the substrate after 15 minutes of exposure

  sition at the source of low intensity. The coating hardens in the form of a rubbery surface without spots and well anchored after an exposure of approximately 2.5 hours, that is to say for a total flux of 15 J / cm2. This observation, associated with the observation of a

  "shadow" in experiment 3, confirms that it is ultraviolet light

which causes hardening.

Example 5

  The pot life of compound baths 1 and 3-6 is determined by

  noting the viscosity as a function of time at a given temperature.

  Table IV shows the time / viscosity relationship at 25 ° C.

Table IV

  Time, Viscosity (cP) of the compositions hours 1 3-6

0 624

  2,686 Gelled in less than 30 minutes

4,760

6,842 "

8 1,025

24 9,000

  Table V shows the time / viscosity relationship at 4 ° C.

Table V

  Time, Viscosity (cP) of the compositions hours 3 4 5 6

0 760 800 600 606

1,890,910,702,730

2,940 1,115 860,882

3 1,135 1,300 980 1,925

4 1,240 1,600 1,200 1,400

Claims (19)

  1. Composition forming a non-stick silicone coating exposed to ultraviolet light sufficient to harden it, characterized in that it consists of: (a) an olefin-organopolysiloxane having units of formula: RaR 'bSiO4-ab (b) an organohydrogenopolysiloxane having units of formula: RaHbSio4-ab in which R is chosen from the group consisting of a   monovalent hydrocarbon radical, a mono- hydrocarbon radical   are halogenated, a cyanoalkyl radical and their mixtures, R 'is an olefinic hydrocarbon radical, has a value of 0 to 3 inclusive, ba has a value of 0.005 to 2.0 inclusive, and the sum of a and ba has a value of 0, 8 to 3 inclusive; (c) an amount of precious metal catalyst sufficient to cause the co-reaction of (a) and (b); and (d) a dialkyl acetylenedicarboxylate corresponding to the general formula ROOCC rCCOOR   wherein R is as defined above and said acetylene-   dialkyl dicarboxylate is present in an amount effective to inhibit premature gelation, but insufficient to prevent cure by exposure to ultraviolet radiation. 2. Composition according to claim 1, characterized in that   that the platinum catalyst is a Karstedt catalyst.   3. Composition according to claim 1, characterized in that   that the platinum catalyst is a Lamoreaux catalyst.   4. Composition according to claim 1, characterized in that   that the olefin-organopolysiloxane is a copolymer of dimethyl-   methylvinylpolysiloxane fluid with dimethylvinyl termination having a viscosity of approximately 300 to 1000 centipoise at 25 ° C. and a content   vinyl from about 0.1 to 2.5% by weight.   5. Composition according to claim 1, characterized in that   that said organohydrogenpolysiloxane is a methylhydrogenopolysi-   Trimethyl-terminated fluid loxane having a viscosity of about 10 to 500 centipoise at 25 ° C and a hydrogen content of about 0.1 to 1.67% by weight. 6. Composition according to claim 1, characterized in that   that said platinum catalyst is present in an amount sufficient   health to bring about 5 to 500 parts of metallic platinum   per million parts of said olefin-organopolysiloxane.   7. Composition according to claim 1, characterized in that said dialkyl acetylenedicarboxylate is present in an amount of about 0.02 to 1.0% by weight of the composition forming a silicone coating.   8. Composition according to claim 1, characterized in that the dialkyl acetylenedicarboxylate is chosen from the group   consisting of dimethyl acetylenedicarboxylate, acetylenededi-   diethyl carboxylate, methyl acetylenedicarboxylate and   ethyl, dibutyl acetylenedicarboxylate and acetylenedicar- methyl butyl boxylate.   9. Composition according to claim 1, characterized in that it further comprises a substrate which has been coated with said   composition forming a silicone coating.   10. Composition according to claim 8, characterized in that that said substrate is paper.   11. Composition according to claim 1, characterized in that   that said olefin-organopolysiloxane is a copolymer of dimethyl-   fluid methylvinylpolysiloxane with dimethylvinyl termination having   a viscosity of around 1,000 to 100,000 centipoise at 25 ° C.   12. Method for rendering surfaces non-adhesive with respect to materials which normally adhere to them, characterized in that it comprises the stages consisting in: A. providing a silicone composition forming a non-stick coating by combination of : (a) an organopolysiloxane olefin having units of formula: RaR 'bSiO4-ab (b) an organohydrogenopolysiloxane having units of formula RaHbSiO4-ab in which R is chosen from the group consisting of a   monovalent hydrocarbon radical, a mono- hydrocarbon radical   are halogenated, a cyanoalkyl radical and their mixtures, R 'is an olefinic hydrocarbon radical, has a value of 0 to 3 inclusive, ba has a value of 0.005 to 2.0 inclusive, and the sum of a and ba has a value of 0, 8 to 3 inclusive; (c) an amount of precious metal catalyst sufficient to cause the co-reaction of (a) and (b); and (d) a dialkyl acetylenedicarboxylate corresponding to the general formula ROOCC-CCOOR   wherein R is as defined above and said acetylene-   dialkyl dicarboxylate is present in an amount effective to inhibit premature gelation, but insufficient to prevent cure by exposure to ultraviolet radiation; o said silicone non-stick coating has a viscosity of about 25 to 5,000 centipoise at 25 ° C; B. coating an appropriate surface of said non-stick silicone coating to a thickness of about 0.0013 to 0.05 millimeters; C. curing said silicone non-stick coating with an amount of ultraviolet light effective to neutralize the curing retardation properties of said dialkyl acetylenedicarbylate. 13. Method according to claim 12, characterized in that 3O   the olefin-organopolysiloxane is a copolymer of dimethylmethyl-   dimethyl vinyl terminated vinylpolysiloxane having a viscosity of about 300 to 1,000 centipoise at 25 ° C and a content of   vinyl from about 0.1 to 25% by weight.   14. Method according to claim 12, characterized in that said organohydrogenpolysiloxane is a methylhydrogenopolysiloxane fluid with trimethyl termination having a viscosity of about 10 to 500 centipoise at 25-C and a hydrogen content of about 0.1 to 1.67% by weight.   15. The method of claim 12, characterized in that said platinum catalyst is present in an amount sufficient to provide about 5 to 500 parts of metallic platinum per   million parts of said olefin-organopolysiloxane.   16. The method of claim 12, characterized in that said dialkyl acetylenedicarboxylate is present in an amount   from about 0.02 to 1.0% of the weight of the coating-forming composition silicone.   17. The method of claim 12, characterized in that said dialkyl acetylenedicarboxylate is chosen from the group   consisting of dimethyl acetylenedicarboxylate and acetylene- diethyl dicarboxylate.   18. Method according to claim 12, characterized in that   the group of radicals represented by R also contains radicals hydroxyl cals.   19. Method according to claim 12, characterized in that   said olefin-organopolysiloxane is a copolymer of dimethyl-   fluid methylvinylpolysiloxane with dimethylvinyl termination having   a viscosity of around 1,000 to 100,000 centipoise at 25 ° C.