JPS6116772B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a polymerizable unsaturated polyester resin syrup composition, a process for curing the polymerizable unsaturated polyester resin syrup composition in the presence of a significant amount of aqueous alkali stabilized colloidal silica, and the flame retardant thermal Concerning cured products. Unsaturated polyester resin syrup is used in coating, molding, casting, and hand laid products such as flat and contoured construction sheets, automotive mudguards and other molded parts, furniture, plumbing fixtures, and ductwork products. , boats, electrical parts housings,
Used for manufacturing electrical circuit boards, etc. Unsaturated polyester resin syrups are often reinforced with fibrous fillers, usually glass fibers, and can be extended with inert particulate fillers such as wood flour, silica, glass beads, clay, calcium carbonate, and the like. “Poiyesters and Their Applications” by Bjorksten et al.
Applications”, Reinhold Publishing Corporation
Corporation), New York (1960), 4th edition. Unsaturated polyester resin syrups have also been bulked up by dispersing water into the resin in the form of small droplets. The emulsion is 40-85% by weight of water combined with 15-60% by weight of unsaturated polyester syrup.
It is described as containing. US Patent No.
See No. 3591191. Compositions containing 50-80% by weight water in a mixture of water and unsaturated polyester resin syrup are described in U.S. Pat. No. 3,687,883. In US Pat. No. 2,610,956, a small amount of silica aerosol was used as a thickener for an unsaturated polyester resin. The flame retardant molding composition of the present invention combines an unsaturated polyester resin syrup and an aqueous alkali stabilized colloidal silica. The present composition does not appear to be a true emulsion, but rather appears to be blended into a useful mixture in which the aqueous alkali stabilized colloidal silica is varied. The body of the unsaturated polyester resin component of unsaturated polyester resin syrups has also changed. In this sense, the flame-retardant molding compositions and products of the present invention differ from the water-expanded polyester resins of the prior art. In the absence of a catalyst, the unsaturated polyester resin is a light blue to amber clear liquid. Aqueous alkali stabilized colloidal silica is a clear to opalescent liquid. Upon mixing, the mixture develops a cloudy white appearance and immediately resembles partially gelled colloidal silica. The viscosity of the mixture increases until it resembles a soft paste with the consistency of china clay. Certain mixtures gel very quickly, producing a hard gel within minutes. Other mixtures thicken more slowly and remain liquid for a considerable time if the water content of the liquid is maintained, ie, without evaporation or freezing. Within about 24 hours all of the above mixtures thicken into the same hard gel. Per part by weight of unsaturated polyester resin syrup
Aqueous alkali stabilized colloidal silica is provided in amounts ranging from 0.1 to 10 parts by weight. As used herein, the expression unsaturated polyester resin syrup refers to the combination of unsaturated polyester resin and copolymerizable monomers that is well known in the art. The preferred aqueous alkali stabilized colloidal silica has a water content of about 50% to about 90%
parts by weight and about 50-10 parts by weight of alkali stabilized colloidal silica solids containing 0.05-0.8 parts by weight _Na2O . A suitable initiating catalyst for the polymerization of the unsaturated polyester resin syrup is included in the composition. These are usually peroxide compounds. A suitable promoter of the initiator may be included. An initiator can be added to the unsaturated polyester resin syrup or to the aqueous alkali stabilized colloidal silica. If used, the cocatalyst is preferably added to the initiator-free liquid component. If a filler is used, it can be added to either or both of the liquid components. Preferably, when the filler is an inert filler such as finely ground perlite or expanded vermiculite, the filler is not used until the two liquids have mixed. Generally, the amount of filler is per part by weight of the mixture of resin syrup and aqueous alkali stabilized colloidal silica.
It can be 0.1 to 5.0 parts by weight. A preferred active filler is aluminum oxide trihydrate, also known as hydrated alumina.
_{It is Al2O3.3H2O} . The fillers can be incorporated into either or both liquid components in amounts up to about 1.5 times the weight of the unsaturated polyester resin syrup and up to about 3 times the weight of the aqueous alkali stabilized colloidal silica. Therefore, the amount of aluminum oxide trihydrate is (a) 1.5 times the weight of the resin syrup and (b)
It should be less than or equal to the sum of 3.0 times the weight of the aqueous alkali stabilized colloidal silica. Preferably, the aluminum oxide trihydrate is ground to a fineness close to that of a -325 mesh US standard sieve. Including aluminum oxide trihydrate in the composition increases the physical strength of the composition, such as hardness and abrasion resistance. When a reinforcing fibrous filler is used, glass fibers are preferred, particularly the glass fibers useful in reinforced plastic sheets, ie, loosely oriented fibers of the type used in glass fiber reinforced plastic laminates. This glass fiber is used as a matte for fiber precipitation.
It can be used as a preformed fiberglass mat, or it can be in the form of a continuous filament or woven fabric. Generally, the glass fiber weight is about 10-200% by weight of the unsaturated polyester resin syrup in the final polymerizable composition. The materials of the invention have excellent processing properties. Within minutes of formation, the resulting shape is strong enough for handling and use. More importantly, this material has a low smoke production capacity when burned. Unsaturated polyester resins are commonly prepared by polyesterification of polycarboxylic acids or polycarboxylic anhydrides with polyols, usually glycols. One of the components of polyester
One contains ethylenic unsaturation and is usually a polycarboxylic acid. Typically, unsaturated polyester resins include phthalic acid, phthalic anhydride, adipic acid, succinic acid, tetrahydrophthalic acid or its anhydride,
Manufactured from dicarboxylic acids such as tetrabromophthalic acid or its anhydride, maleic acid or its anhydride, fumaric acid. Representative glycols include ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, diethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol. Trihydric and higher polyols such as trimethylolethane, trimethylolpropane, pentaerythritol are sometimes included in the polyester. Usually a slight superstoichiometric excess of glycol is used in the production of unsaturated polyesters. When an unsaturated polyester resin is combined with a copolymerizable monomer containing terminal vinyl groups, an unsaturated polyester resin syrup is obtained. The above monomers include styrene, α-methylstyrene, o-chlorostyrene,
Including vinyltoluene, acrylic acid, methacrylic acid, alkyl acrylate, alkyl methacrylate, divinylbenzene, diacrylate, dimethacrylate, triacrylate, trimethacrylate and the like. Typically, the copolymerizable monomer is provided in an amount constituting about 10-40% by weight of the unsaturated polyester resin syrup. That is, the unsaturated polyester resin constitutes approximately 90-60% by weight of the resin syrup. A preferred modified copolymerizable monomer is a reaction product of polyepoxide and acrylic acid or methacrylic acid. The above products are described in US Pat. No. 3,373,075, No.
Described in No. 3301743. Similar products can be prepared by combining polyols such as bisphenol A with glycidyl acrylate or glycidyl methacrylate. The modified copolymerizable monomers described above can be used in place of a portion of other copolymerizable monomers or in place of a portion of the unsaturated polyester resin in the resin syrup. The aqueous alkali stabilized colloidal silica has the properties shown in Table 1.

[Table] The preferred average particle size is approximately 15 millimicrons, PH
Approximately 9.7, viscosity approximately 12cp, _Na2O content approximately 0.4% by weight,
(SiO ₂ )x concentration of about 40% by weight. Aqueous alkali stabilized colloidal silica is commercially available from Nalco Chemical Co., Ltd. and Eldu Pont de Nemours Co. Aqueous alkaline stabilized colloidal silica dispersions can be made by converting aqueous sodium silicate to aqueous silicic acid by removal of sodium ions. One method of performing sodium ion removal is to pass a dilute aqueous sodium silicate solution through a cation exchange resin in the hydrogen form. Effluent aqueous silicic acid solutions are generally unstable, but can be stabilized by adding sufficient alkali in the form of sodium, potassium, lithium, or ammonium ions. The alkali-stabilized aqueous solution can thus be dehydrated to approach a minimum water content which varies somewhat depending on each individual composition. The water content of colloidal silica cannot be reduced below a critical minimum water level without irreversibly converting it to silica glass. Water content may not be lost due to evaporation or unintentional freezing of the aqueous dispersion. Both freezing and evaporation should be avoided to prevent irreversible glass formation. Aqueous alkali stabilized colloidal silica is
Density approximately 10.0-11.5 lb/gal at 15.6°C and 25°C
It is a pale milky white liquid with a viscosity of about 4 to 10 centipoise. When distributed commercially with just above a minimum water content, the silica content, expressed as (SiO ₂ ) x, is between 10 and 50% by weight. When using sodium hydroxide as a stabilizing alkali, the alkali content is
It ranges from about 0.05 to 0.8% by weight for _Na2O and about 0.25% by weight for _NH3 when ammonia is used. The average particle size of the colloidal silica particles ranges from 4 to 60 millimicrons. As shown in Table 2, two representative commercially available products are sold by DuPont under the trade name LUDOX.

Table: Typical initiators for unsaturated polyester resin syrups include peroxides such as benzoyl peroxide, cumene hydroperoxide, tert-butyl peroxide, and the like. A particularly useful peroxide initiator for room temperature curing is 3,5-dimethylhexane-2,5-dimethyl-diper-2-ethylhexoate.
Peroxide initiators are usually supplied in the form of a paste dispersed in glycol. Cocatalysts for peroxidation initiators include, for example, cobalt naphthenate and cobalt octoate. Mixing the liquid unsaturated polyester resin syrup and the aqueous alkali stabilized colloidal silica can be accomplished in several ways. The above substances can be poured into a regular container and stirred. Both liquid substances can be sprayed separately to form a spray that collides with each other, resulting in a mixed spray in which the spray particles are uniformly mixed. Both liquids can be introduced into a spray device which has a conventional mixing chamber before the spray nozzle. The peroxide initiator is chosen so that the initiation of polymerization of the unsaturated polyester resin syrup can be controlled by the operator. Peroxide initiators are usually chosen which require heating of the composition to initiate polymerization, ie so-called high temperature initiators. In a preferred embodiment of the invention, the unsaturated polyester resin syrup includes powdered hydrated alumina and the aqueous alkali stabilized colloidal silica also includes hydrated alumina. The amount of unsaturated polyester resin syrup is minimized so that the final product has a low fuel content. When exposed to fire, the cured product resists temperature increases initially due to thermal dehydration of the hydrated alumina and later due to vitrification of the colloidal silica. According to the method of the present invention, the two components of unsaturated polyester resin syrup and aqueous alkali stabilized colloidal silica are mixed together with the polymerization initiator of the unsaturated polyester resin syrup.
Cured thermoset articles can be produced from the component mixture. The composition is formed into the desired shape and retains that shape until the composition is cured. This shaping can be done by molding, pressing, pouring, hand lay-up, spraying onto a substrate, troweling, extruding, rolling, etc. A polymerization initiator can be included in either of the two components. If a high temperature initiator is used, it is preferred that the initiator be included in the unsaturated polyester resin. When a room temperature initiator is used, it is preferably included in the aqueous alkaline stabilized colloidal silica solution. In that case, the polymerization cocatalyst is included in the unsaturated polyester resin syrup. The two components can be mixed in a mixing tank or pipe. The two components can be formed separately into a pneumatically conveyed spray that is allowed to impinge on each other to achieve the desired mixing. The two components can be mixed in a mixing chamber and sprayed as a mixture onto a substrate. Either or both of the two components can include an inert filler. Preferably with fillers such as finely ground nacre or expanded vermiculite, this inert filler is added to the components after they have been mixed. A particularly preferred product obtained by the practice of this invention is a fiber-reinforced laminate article containing loosely oriented reinforcing fibers, such as glass fibers, having a thermoset resinous composition dispersed in the continuous phase. The resinous composition in cured form comprises an unsaturated polyester resin crosslinked with copolymerizable monomers of a polyester resin syrup. However, unsaturated polyesters are slightly modified in that some of the initially unreacted carboxylic acid groups in unsaturated polyesters are converted to carboxylic acid groups by the presence of the alkali stabilizer in the colloidal silica dispersion. has been done. The unsaturated polyester resin retains some of its unreacted carboxylic acid groups. Evidence of both carboxylic acid groups and carboxylic acid bases was seen in infrared spectroscopic analysis of the cured product. When the effective role of the alkaline stabilizer in the mixture is removed, the colloidal silica becomes unstable, where it rapidly and irreversibly forms a cohesive gel that is uniformly dispersed throughout the cured unsaturated polyester resin syrup. Gel. Preferably, the laminate contains glass fibers as reinforcing fibers in an amount of about 6 to 30% of its weight. The useful laminate-forming polymerizable compositions described above contain from about 0.1 to 5.0 parts by weight of reinforcing fibers per part by weight of the mixture of unsaturated polyester resin syrup and aqueous alkali stabilized colloidal silica. The laminate can be further reinforced by including a sheet of metallic lath steel as a core. Typical products of this composition include furniture, frame moldings, lamp stands, statues, skeet targets, poured articles such as toys, automotive exterior elements, molded articles such as electrical housings, boat hulls, bathroom sinks, pipes. , shower compartments, band lay-up or spray-up articles such as cargo containers,
Architectural structural panels, ventilation components, hoods, ducts,
reinforced laminates such as ceiling tiles, window frames, and doors;
Cast-in-press or spray-in-press articles such as flame retardant coatings. According to the invention, (1) unfilled or filled with active fillers such as hydrated alumina or other hydrated metal salts or oxides, and/or such as silica, calcium carbonate, etc. (2) a liquid or pasty pourable and/or sprayable polymerizable unsaturated polyester resin syrup filled with an inert filler; and (2) unfilled or hydrated alumina or other hydrated metal. Openable and/or consisting of an aqueous alkaline stabilized colloidal silica solution which can be filled with active fillers such as salts or oxides and/or which can be filled with inert fillers such as silica, calcium carbonate. Useful products are made by mixing with sprayable liquids. An unsaturated polyester resin syrup polymerization initiator is included in the mixture. mixture, refractory aggregate, frosted glass, glass microspheres,
Inert fillers such as silica, magnesium oxide, mullite, fly ash, zirconia, clay, bentonite, kaolin, attapulgide, titanium dioxide, antimony oxide, pigments, low density insulating materials such as perlite or expanded vermiculite,
The mixture can be further enriched by incorporating fibrous reinforcing materials such as glass fibers, alvesto fibers, mineral wool into the mixture. Inert fillers tend to increase or decrease the density of the final product, depending on the filler selected, and also tend to reinforce the resulting product, especially when fibrous fillers are selected. The non-flammable filler disperses the twistable components and thus lowers the fuel content of the final product. Filling agent is mixture 1
It can consist of 0.1 to 5.0 parts by weight per part by weight. To minimize the tendency for the water content of the aqueous alkali stabilized colloidal silica to evaporate, it is preferred to cure the materials of the present invention at temperatures below about 100°C. Excessive curing temperatures can lead to fracture or spalling of the resulting shaped article. When mixing the above two parts together with suitable fillers, in a preferred embodiment the consistency of the product is similar to china clay. At this consistency, the mixture can be troweled and applied to horizontal, vertical, or overhead surfaces to obtain a coating by troweling, rolling, pressing, or extrusion, if desired. The above mixture can be injection molded, press molded, or hand laid.
Can be used in up or pour operations. Preferably, the viscosity of the unsaturated polyester resin syrup ranges from about 50 to 5000 centipoise. The increase in viscosity that occurs when mixing aqueous alkali stabilized colloidal silica and unsaturated polyester resin syrup appears to be the result of several competing phenomena. This is primarily due to (A) the formation of small amounts of carboxylate salts from the reaction of the unreacted carboxylic acid groups of the unsaturated polyester resin with the alkali metal ions of the aqueous alkali-stabilized colloidal silica; This is a change to silica gel. Many factors influence the rate of viscosity increase, including the Na ₂ O and SiO ₂ content, the acid number of the unsaturated polyester resin, the initial viscosity of the unsaturated polyester resin syrup and the aqueous alkali stabilized colloidal silica. To some extent, the viscosity increase depends on the amount and type of polymerizable monomers included in the unsaturated polyester resin syrup, and the type and concentration of particulate fillers in the mixture can also influence the viscosity increase. Silica gel is known to exist in at least three different types including polymeric gels, flocculated gels, and mixed or hybrid gels. Neutralization converts the aqueous sodium silicate to silicic acid, resulting in a polymeric gel. The polymer gel consists of polysilicate ions that extend through the solution as a three-dimensional cross-linked network structure. A flocculent gel forms when preformed colloidal silica particles are bonded with siloxane bonds through attachment points. The hybrid gel appears to be a combination of the first two forms of gel and contains preformed colloidal silica particles bound by polysilicate chains. Generally, the cured product obtained by polymerization of a mixture of unsaturated polyester resin syrup and aqueous alkali stabilized colloidal silica is at least 5% by weight.
colloidal silica gel, which is generated in situ and homogeneously dispersed with a cross-linked unsaturated polyester resin syrup, in which at least a portion of the cross-linked polyester remains unreacted with the carboxylic acid groups in its polymerized state. Contains both carboxylic acid groups. Example 1 An unsaturated polyester resin syrup (hereinafter referred to as resin syrup) contained 25 parts by weight of styrene and 75 parts by weight of an unsaturated polyester resin obtained as follows. Mix 60 moles of flutaic anhydride, 40 moles of maleic anhydride, and 106 moles of propylene glycol,
It was esterified to an acid value of approximately 20 to create a general-purpose unsaturated polyester resin. 1 g of benzoyl peroxide powder was added as a catalyst to 100 g of unsaturated polyester resin syrup (). This unsaturated polyester resin syrup was mixed with 60% water and 40% silica solids by weight.
% by weight of aqueous alkali stabilized colloidal silica LUDOX HS40 (see Table 2). After mixing the two liquids, the viscosity of the mixture began to increase. This mixture has a ring diameter of 6 inches.
It was applied to a cellophane sheet within an O-ring in a 1/2 inch diameter tube. Apply a second sheet of cellophane to the top of the O-ring and press the resulting cellophane sheet to a thickness of 1/2 inch thick and 6 mm in diameter.
I made an inch disk. This disk was placed in a 90°C oven for approximately 15 minutes. The discs were allowed to cure overnight, losing some water content by evaporation. The disc had a chalky white appearance and a specific gravity of 0.82. The disc was placed on a ring stand approximately 2 inches above the Bunsen burner. The Bunsen burner's flame hit the disc. A small amount of smoke was observed within the first 5 minutes of impact. After that, no smoke was detected. The discs remained on the Bunsen burner for 6 hours. While exposed to the flame, the disc retained its shape and integrity. Example 2 Example 1 was repeated, except that the nonionic surfactant Triton X, available from Rohm & Hass Co.
An unsaturated polyester resin syrup () was modified by including two drops of -100. This resin syrup () was mixed with aqueous alkali stabilized colloidal silica (LUDOX HS40, see Table 2) and formed into disks 1/2 inch thick and 6 inches in diameter. This disk was tested in the manner described in Example 1,
Identical results were obtained. From Example 2, the absence of surfactant (Example 1) is different from the presence of surfactant (Example 2).
It is concluded that they cannot be distinguished. Example 3 Unsaturated polyester resin syrup () 50g
was mixed with 50 g of alumina trihydrate on a -325 mesh US standard sieve and 0.5 g of benzoyl peroxide powder to prepare component (1). 50 g of aqueous alkali-stabilized colloidal silica (LUDOX TM, see Table 2)
was mixed with 50 g of alumina trihydrate on a -325 mesh US standard sieve to prepare component (2). When alumina trihydrate was mixed with aqueous alkali stabilized colloidal silica, a thixotropic strip with a viscosity of 70-6000 centipoise (Brookphie-ld) was formed. Ingredients (1) and ingredients
Stir (2) together in a beaker to form a disk with a thickness of 1/4 inch and a diameter of 4 inches. Hold this disk at 90℃
Cured in oven for 15 minutes. The discs had a chalky white appearance, had a specific gravity of 1.3, and were tested as described in Example 1. Essentially no smoke or flame was detected during the 6 hour test. The burnt out disk appeared to be a continuous lightweight composition. Example 3 shows a composition extended with an equal weight of alumina trihydrate based on the combined weight of unsaturated polyester resin syrup and alkali stabilized colloidal silica. Example 4 Example 3 was repeated, except that pearlite (-40
10g of mesh US standard sieve) component (1) and component (2)
The mixture was thoroughly mixed. This composition is 3/8 thick
inch, and was molded into a 3 inch diameter disc. The discs were cured and tested as described in Example 1. No smoke or flame was detected during the test. After the sample was placed in the flame of a Bunsen burner for one hour, the upper side could be touched without pain, indicating that it had excellent thermal insulation properties. Example 5 Example 3 was repeated with two variations. One variation is that the alumina trihydrate is a -100 mesh US standard sieve. The second variation was that the aqueous alkali stabilized colloidal silica component contained 0.1 g of N,N-dimethylaniline as a polymerization cocatalyst. Components (1) and (2) were mixed and formed into a disk 1/4 inch thick and 4 inches in diameter. The discs cured in about 1 hour at room temperature. This example shows that it is possible to incorporate a polymerization catalyst into an unsaturated polyester resin syrup and a polymerization cocatalyst into an aqueous alkali stabilized colloidal silica. Example 6 Example 3 was repeated with one modification. Component (1) is polymerizable unsaturated polyester resin syrup ()50
g, 50 g of alumina trihydrate (-325 mesh US standard sieve), 0.1 g of methyl ethyl ketone peroxide (60% solution in dimethyl phthalate),
Cobalt naphthenate (6% solution in glycol) 20
It was made up of drops. The viscosity of component (1) is approximately 4000~
It was 5000 centipoise (Burtskfield). Ingredient (2) was the same as in Example 3. Components (1) and (2) were stirred with a spatula in a beaker to mix thoroughly, and the mixture was formed into a disk having a thickness of 1/4 inch and a diameter of 4 inches. The disc cured in approximately 45 minutes at room temperature. This example shows that a catalyst and cocatalyst can be incorporated into an unsaturated polyester resin syrup. Example 7 A number of disks were made using component (1) and component (2) as described in Example 5. The ratio of component (1) to component (2) is
80/20, 60/40, 50/50, 40/60, 20/80, 10/
It was 90. Add each formulation to a thickness of 1/4 inch and a diameter of 4
It was molded into an inch disc. Each disc was tested as described in Example 1. The test results are shown in the table below.

【table】

TABLE 3 It can be seen from Table 3 that the samples (A, B) with a high content of unsaturated polyester resin syrup tend to produce smoke and flame and deteriorate when burned. As the amount of unsaturated polyester resin syrup is reduced, the amount of smoke and flame is reduced and the flame resistance increases. As the amount of unsaturated polyester resin syrup decreased, mixing became increasingly difficult. Samples A, B, C, and D mixed easily. Sample E had little difficulty in mixing. Sample F was completely difficult to mix, that is, its workability was poor.

Claims (1)

[Claims] 1 (a) 1 part by weight of a mixture of unsaturated polyester resin syrup and aqueous alkali-stabilized colloidal silica in a mixing ratio (by weight) of 50:50 to 20:80; (b) A polymerizable composition for a flame-retardant molded article, comprising a catalytic amount of a polymerization initiator for the unsaturated polyester resin syrup. 2. Claim 1, wherein the aqueous alkali-stabilized colloidal silica comprises 10 to 50 parts by weight of colloidal silica having an average particle size of 4 to 60 millimicrons.
The polymerizable composition described in . 3. The unsaturated polyester resin syrup is (A) an unsaturated polyester resin consisting of a reaction product of a polyhydric alcohol and a polycarboxylic acid or anhydride of which at least a portion is an ethylenically unsaturated polycarboxylic acid or its anhydride; B) at least one copolymer monomer having ethylenic unsaturation. 4 (a) 1 part by weight of a mixture of unsaturated polyester resin syrup and aqueous alkali-stabilized colloidal silica in a mixing ratio (by weight) of 50:50 to 20:80; (b) a catalytic amount of said unsaturated silica; A polymerizable composition for a flame-retardant molded article, comprising: a polymerization initiator for saturated polyester resin syrup; and (c) 0.1 to 5.0 parts by weight of a finely pulverized filler. 5. The polymerizable composition according to claim 4, wherein the pulverized filler is aluminum oxide trihydrate. 6. Polymerizable according to claim 5, wherein the amount of aluminum oxide trihydrate is less than the sum of 1.5 times the weight of the unsaturated polyester resin syrup and 3.0 times the weight of the aqueous alkali stabilized colloidal silica. Composition. 6. The polymerizable composition of claim 4, which is a finely divided filler inert material. 7. The polymerizable composition according to claim 6, wherein the pulverized filler is perlite. 8. The polymerizable composition according to claim 6, wherein the pulverized filler is expanded vermiculite. 9. The polymerizable composition of claim 4, wherein the pulverized filler is glass fiber comprising 10 to 200% by weight of the unsaturated polyester resin syrup.