The pre-impregnated material is made of aresin and a carrier composed of a sheet-like material. Wherein the resin is inB-stage, under the action of temperature and pressure, having a fluidity andcan be cured rapidly and to complete the bonding process, and together with thecarrier constituting the insulating layer. Commonly known as prepreg oradhesive sheet. In order to ensure that the multilayer printed circuit board ofhigh reliability and stability of the quality, the characteristics of thesemi-solid piece must conduct quality testing (test lamination method). Thecharacteristics of the prepreg contains the features and laminated beforelamination characteristics in two parts. Prior to lamination features mainlyrefers to the: resin content%, the liquidity%, volatile matter content% and geltime (S). After lamination characteristics means: electrical properties,thermal shock resistance and flammability. For this reason, in order to ensurethe stability of the multilayer printed circuit board of high reliability thesurname and laminating process parameters, detected prior to lamination of theprepreg characteristics are very important.

1. Resin content (%) Found:

(1) production of the test piece: Pressprepreg fiber direction: a 45 ° angle cut into 100 × 100 (mm) of a small testblock;

(2) were weighed: using an accuracy of 0.001 g balance weighing WL (g);

(3) heating: the temperature was heated to 566.14 ℃ burning for 60 minutes, cooled andthen were weighed W2 (g);

(4) Calculation: W1-W2

  Resin content (%) = (W1-W2) /W1 × 100

2 Determination of the resin flow rate (%):

(1) sample preparation: the fiber directionof the prepreg, the 100 × 100 (mm) at a 45 ° angle cut into several pieces ofabout 20 g of thetest piece;

(2) weighing: using an accuracy of 0.001 g balance accurately weighed at W1 (g);

(3) heating and pressurizing: the pressingbed heating plate temperature was adjusted to 171 ° C ± 3 ° C. When thespecimen placed within the heating plate, the applied pressure is less than 14± 2Kg/cm2, heated andpressurized for 5 minutes, the effluent gum resection and conducting weighingW2 (g);

(4) Calculate: Resin flow (%) = (W1-W2) /W1 × 100

3 Determination of gel time:

(1) sample preparation: the prepreg fiberdirection to an angle of 45 ° was cut into 50 × 50 (mm), the number of blocks(each about 15 grams);

(2) heated pressurized: adjust heatingplate temperature of 171 ± 3 ℃, pressurefor 35Kg/cm2pressing time 15 seconds;

(3) Test: A test piece from the pressurizedstart time to the curing time to the result of the measurement.

4. Volatile matter content side is given:

(1) sample preparation: the fiber directionof the prepreg, to an angle of 45 ° was cut into 100 × 100 (mm) 1 block;

W1 (g) (2) weighing: using an accuracy of 0.001 g weighing scales;

(3) heating: the use of an air circulationtype thermostatic chamber, and then use the weighing scales W2 (g) was heatedat 163 ± 3 ° C for 15 minutes;

(4) Calculation: volatile matter (%) =(W1-W2) / W1 × 100